Illumination unit, projection display unit, and direct-view display unit

The present application claims priority to Japanese Priority Patent Application JP 2012-127017 filed in the Japan Patent Office on Jun. 4, 2012, the entire content of which is hereby incorporated by reference.

The present disclosure relates to an illumination unit using a solid-state light-emitting device such as a laser diode (LD), and a projection display unit and a direct-view display unit each of which includes the illumination unit.

In recent years, projectors projecting an image onto a screen are widely used not only in offices but also in households. A typical projector modulates light from a light source with use of a light valve to generate image light, and projects the image light onto a screen to thereby perform display (for example, refer to Japanese Unexamined Patent Application Publications No. 2011-128634 and 2010-48903). Recently, palm-sized ultra-compact projectors, cellular phones with a built-in ultra-compact projector, and the like are being introduced.

High-intensity discharge lamps are dominant light sources used for projectors. However, since the discharge lamps have a relatively large size and high power consumption, in recent years, solid-state light-emitting devices such as light-emitting diodes (LEDs), laser diodes (LDs), and organic ELs (OLEDs) have been attracting attention as alternatives to the discharge lamps. These solid-state light-emitting devices have advantages over the discharge lamps not only in size and power consumption but also in high reliability. In particular, to achieve higher luminance and lower power consumption, it is effective to enhance light use efficiency with use of LDs which are point light sources.

Thus, in light sources (illumination units) for projectors and the like, in general, higher luminance of illumination light and an improvement in light use efficiency are desired, and it is desirable to achieve them with a simple (small) configuration.

It is desirable to provide a illumination unit capable of improving light use efficiency with a simple configuration while achieving higher luminance of illumination light, and a projection display unit and a direct-view display unit each of which uses such an illumination unit.

According to an embodiment of the disclosure, there is provided an illumination unit including: one or more light sources each including a solid-state light-emitting device, the solid-state light-emitting device emitting light from a light emission region thereof, the light emission region including a plurality of light-emitting spots arranged along a predetermined direction; and an optical member allowing light incident from the solid-state light-emitting device to pass therethrough and exit therefrom, in which the optical member includes one or more coupling lenses changing a directivity angle of the light incident from the solid-state light-emitting device, the solid-state light-emitting device includes a single chip or a plurality of chips, the single chip emitting light in a single wavelength range or light in a plurality of wavelength ranges, the plurality of chips emitting light in a same wavelength range or light in wavelength ranges different from one another, the single chip or the plurality of chips in the solid-state light-emitting device having the plurality of light-emitting spots each include a laser diode, and a first coupling lens of the one or more coupling lenses has a smaller lens effect along the predetermined direction than a lens effect along a direction orthogonal to the predetermined direction in the light emission region, the first coupling lens on which laser light emitted from the solid-state light-emitting device having the plurality of light-emitting spots is incident.

According to an embodiment of the disclosure, there is provided a projection display unit provided with an illumination optical system, a spatial modulating device, and a projection optical system, the spatial modulating device modulating light from the illumination optical system based on an input image signal to generate image light, the projection optical system projecting the image light generated by the spatial modulating device, the illumination optical system including: one or more light sources each including a solid-state light-emitting device, the solid-state light-emitting device emitting light from a light emission region thereof, the light emission region including a plurality of light-emitting spots arranged along a predetermined direction; and an optical member allowing light incident from the solid-state light-emitting device to pass therethrough and exit therefrom, in which the optical member includes one or more coupling lenses changing a directivity angle of the light incident from the solid-state light-emitting device, the solid-state light-emitting device includes a single chip or a plurality of chips, the single chip emitting light in a single wavelength range or light in a plurality of wavelength ranges, the plurality of chips emitting light in a same wavelength range or light in wavelength ranges different from one another, the single chip or the plurality of chips in the solid-state light-emitting device having the plurality of light-emitting spots each include a laser diode, and a first coupling lens of the one or more coupling lenses has a smaller lens effect along the predetermined direction than a lens effect along a direction orthogonal to the predetermined direction in the light emission region, the first coupling lens on which laser light emitted from the solid-state light-emitting device having the plurality of light-emitting spots is incident.

According to an embodiment of the disclosure, there is provided a direct-view display unit provided with an illumination optical system, a spatial modulating device, a projection optical system, and a transmissive screen, the spatial modulating device modulating light from the illumination optical system based on an input image signal to generate image light, the projection optical system projecting the image light generated by the spatial modulating device, the transmissive screen displaying the image light projected from the projection optical system, the illumination optical system including: one or more light sources each including a solid-state light-emitting device, the solid-state light-emitting device emitting light from a light emission region thereof, the light emission region including a plurality of light-emitting spots arranged along a predetermined direction; and an optical member allowing light incident from the solid-state light-emitting device to pass therethrough and exit therefrom, in which the optical member includes one or more coupling lenses changing a directivity angle of the light incident from the solid-state light-emitting device, the solid-state light-emitting device includes a single chip or a plurality of chips, the single chip emitting light in a single wavelength range or light in a plurality of wavelength ranges, the plurality of chips emitting light in a same wavelength range or light in wavelength ranges different from one another, the single chip or the plurality of chips in the solid-state light-emitting device having the plurality of light-emitting spots each include a laser diode, and a first coupling lens of the one or more coupling lenses has a smaller lens effect along the predetermined direction than a lens effect along a direction orthogonal to the predetermined direction in the light emission region, the first coupling lens on which laser light emitted from the solid-state light-emitting device having the plurality of light-emitting spots is incident.

In the illumination unit, the projection display unit, and the direct-view display unit according to the embodiments of the disclosure, the single chip or the plurality of chips in the solid-state light-emitting device having the plurality of light-emitting spots each include a laser diode; therefore, higher luminance of illumination light is achieved. Moreover, since the coupling lens changing the directivity angle of light incident from the solid-state light-emitting device is provided as the optical member allowing light incident from the solid-state light-emitting device to pass therethrough and exit therefrom, use efficiency of light emitted from the light source is improved. Moreover, in the first coupling lens on which laser light emitted from the solid-state light-emitting device having the plurality of light-emitting spots is incident, the lens effect along the predetermined direction (the arrangement direction of the plurality of light-emitting spots) is smaller than the lens effect along the direction orthogonal to the above-described predetermined direction. Therefore, light use efficiency is improved while achieving simplification (downsizing) of a configuration.

In the illumination unit, the projection display unit, and the direct-view display unit according to the embodiments of the disclosure, the single chip or the plurality of chips in the solid-state light-emitting device having the plurality of light-emitting spots each include the laser diode, and the coupling lens changing the directivity angle of light incident from the solid-state light-emitting device is provided; therefore, light use efficiency is improvable while achieving higher luminance of illumination light. Moreover, in the first coupling lens on which the laser light emitted from the solid-state light-emitting device having the plurality of light-emitting spots is incident, the lens effect along the predetermined direction (the arrangement direction of the plurality of light-emitting spots) is smaller than the lens effect along the direction orthogonal to the above-described predetermined direction; therefore, light use efficiency is improvable while achieving simplification (downsizing) of the configuration. Thus, light use efficiency is improvable with a simple configuration while achieving higher luminance of illumination light, and display image quality is improvable.

It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the technology as claimed.

Additional features and advantages are described herein, and will be apparent from the following Detailed Description and the figures.

The accompanying drawings are included to provide a further understanding of the technology, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments and, together with the specification, serve to explain the principles of the technology.

FIGS. 1A and 1B are diagrams illustrating a schematic configuration of a projector according to an embodiment of the disclosure.

FIGS. 2A and 2B are diagrams illustrating an example of optical paths in the projector illustrated in FIGS. 1A and 1B .

FIGS. 3A and 3B are diagrams illustrating an example of a top configuration and a sectional configuration of the light source illustrated in FIGS. 1A and 1B in the case where a chip in the light source is of a top emission type.

FIGS. 4A and 4B are diagrams illustrating another example of the top configuration and the sectional configuration of the light source illustrated in FIGS. 1A and 1B in the case where the chip in the light source is of the top emission type.

FIGS. 5A and 5B are diagrams illustrating an example of a light-emitting spot in the light source illustrated in FIGS. 1A and 1B in the case where the chip in the light source is of the top emission type.

FIGS. 6A and 6B are diagrams illustrating an example of a sectional configuration of the light source illustrated in FIGS. 1A and 1B and a configuration of a solid-state light-emitting device when viewed from a light emission surface side thereof in the case where the chip in the light source is of an edge emission type.

FIGS. 7A and 7B are diagrams illustrating another example of the sectional configuration of the light source illustrated in FIGS. 1A and 1B and the configuration of the solid-state light-emitting device when viewed from the light emission surface side thereof in the case where the chip in the light source is of the edge emission type.

FIGS. 8A to 8C are diagrams illustrating still another example of the sectional configuration of the light source illustrated in FIGS. 1A and 1B and the configuration of the solid-state light-emitting device when viewed from the light emission surface side thereof in the case where the chip in the light source is of the edge emission type.

FIGS. 9A and 9B are diagrams illustrating schematic configurations of a fly-eye lens illustrated in FIGS. 1A and 1B .

FIG. 10 is a perspective view illustrating an example of optical paths in an illumination optical system illustrated in FIGS. 1A and 1B .

FIG. 11 is a schematic view illustrating a luminance distribution example of incident light on a fly-eye lens located in a preceding stage illustrated in FIGS. 1A and 1B .

FIGS. 12A and 12B are schematic views illustrating examples of a relationship between a luminance distribution region illustrated in FIG. 11 and a pitch of a cell in the fly-eye lens.

FIGS. 13A to 13C are plots illustrating examples of a luminance distribution shape according to a ratio of an effective size in the fly-eye lens to the pitch of the cell.

FIGS. 14A and 14B are diagrams illustrating an example of a schematic configuration of an illumination optical system and optical paths according to Modification 1.

FIGS. 15A and 15B are diagrams illustrating an example of a schematic configuration of an illumination optical system and optical paths according to Modification 2.

FIGS. 16A and 16B are diagrams illustrating an example of a schematic configuration of an illumination optical system and optical paths according to Modification 3.

FIGS. 17A and 17B are diagrams illustrating a schematic configuration of a projector according to Modification 4.

FIGS. 18A and 18B are diagrams illustrating a schematic configuration of a projector according to Modification 5.

FIG. 19 is a diagram illustrating a schematic configuration example of a rear-projection display unit using any one of the illumination optical systems according to the embodiment and Modifications 1 to 5.

Some embodiments of the present disclosure will be described in detail below referring to the accompanying drawings. It is to be noted that description will be given in the following order.

1. Embodiment (An example using two cylindrical lenses which are a concave lens and a convex lens)

2. Modifications of Embodiment

Modification 1 (An example using a cylindrical lens and an anamorphic lens)

Modification 2 (An example using two cylindrical lenses which are convex lenses)

Modification 3 (An example using one cylindrical lens which is a convex lens)

Modification 4 (An example in which only one light source is included in an illumination optical system)

Modification 5 (An example using a reflective device as a spatial modulating device)

3. Other Modifications (Combinations of any of the embodiment, the modifications, and the like, an application example to a rear-projection display unit, and the like)

Embodiment

Entire Configuration of Projector 1

FIGS. 1A and 1B illustrate a schematic configuration of a projector (a projector 1 ) according to an embodiment of the disclosure. It is to be noted that the projector 1 corresponds to a specific example of “projection display unit” in an embodiment of the disclosure. FIG. 1A illustrates a configuration example of the projector 1 when viewed from above (from a y-axis direction), and FIG. 1B illustrates a configuration example of the projector 1 when viewed from a side thereof (from an x-axis direction). FIGS. 2A and 2B illustrate an example of optical paths in the projector 1 in FIGS. 1A and 1B . FIG. 2A illustrates an example of the optical paths when the projector 1 is viewed from above (from the y-axis direction), and FIG. 2B illustrates an example of the optical paths when the projector 1 is viewed from a side thereof (from the x-axis direction).

Typically, a y axis is directed toward a vertical direction, and an x axis is directed toward a horizontal direction; however, the y axis may be directed toward the horizontal direction, and the x axis may be directed toward the vertical direction. It is to be noted that, for convenience sake, in the following description, the y axis and the x axis are directed toward the vertical direction and the horizontal direction, respectively. Moreover, in the following description, a “transverse direction” indicates the x-axis direction, and a “longitudinal direction” indicates the y-axis direction.

The projector 1 may include, for example, an illumination optical system 1 A, a spatial modulating device 60 , and a projection optical system 70 . The spatial modulating device 60 modulates light from the illumination optical system 1 A based on an input image signal to generate image light, and the projection optical system 70 projects the image light generated by the spatial modulating device 60 onto a reflective screen 2 . The illumination optical system 1 A corresponds to a specific example of “illumination unit” in an embodiment of the disclosure.

Configuration of Illumination Optical System 1 A

The illumination optical system 1 A provides a light flux which is applied to an illumination region 60 A (an illuminated surface) of the spatial modulating device 60 . It is to be noted that, as necessary, any optical device may be included in a region where light of the illumination optical system 1 A passes. For example, a filter which attenuates light, other than visible light, from the illumination optical system 1 A, or the like may be included in the region where light of the illumination optical system 1 A passes.

For example, as illustrated in FIGS. 1A and 1B , the illumination optical system 1 A includes light sources 10 A, 10 B, and 10 C, coupling lenses (directivity angle changing devices) 20 A, 20 B, and 20 C, an optical path combining device 30 , an integrator 40 , and a condenser lens 50 . The optical path combining device 30 combines light from the light sources 10 A, 10 B, and 10 C, and may be configured of, for example, two dichroic mirrors 30 A and 30 B. The integrator 40 uniformizes an illuminance distribution (a luminance distribution) of light in the illumination region 60 A, and may be configured of, for example, a pair of fly-eye lenses 40 A and 40 B. Alternatively, the integrator 40 may be configured of only one fly-eye lens. The coupling lens 20 A, the optical path combining device 30 , the integrator 40 , and the condenser lens 50 are arranged in this order from a side closer to the light source 10 A along an optical axis of the light source 10 A. An optical axis of the light source 10 B is orthogonal to the optical axis of the light source 10 A on the dichroic mirror 30 A, and the coupling lens 20 B and the dichroic mirror 30 A are arranged in this order from a side closer to the light source 10 B along the optical axis of the light source 10 B. An optical axis of the light source 10 C is orthogonal to the optical axis of the light source 10 A on the dichroic mirror 30 B, and the coupling lens 20 C and the dichroic mirror 30 B are arranged in this order from a side closer to the light source 10 C along the optical axis of the light source 10 C.

The coupling lenses 20 A, 20 B, and 20 C, and the integrator 40 from among the above-described components correspond to specific examples of “optical member (optical member allowing incident light from a solid-state light-emitting device which will be described later to pass therethrough and exit therefrom)” in an embodiment of the disclosure. Moreover, the coupling lens 20 A corresponds to a specific example of “first coupling lens” in an embodiment of the disclosure.

It is to be noted that, in FIGS. 1A and 1B , the case where respective components (except for the light sources 10 B and 10 C and the coupling lenses 20 B and 20 C) of the projector 1 are arranged on a line segment parallel to a z axis is illustrated; however, some of the respective components of the projector 1 may be arranged on a line segment not parallel to the z axis. For example, although not illustrated, the entire illumination optical system 1 A may be rotated by 90° from a state illustrated in FIGS. 1A and 1B to allow an optical axis of the illumination optical system 1 A to be oriented toward a direction orthogonal to the z axis. However, in such a case, it is necessary to provide an optical device (for example, a mirror) guiding light output from the illumination optical system 1 A toward the spatial modulating device 60 . Moreover, for example, the light source 10 A, the coupling lens 20 A, and the optical path combining device 30 may be rotated by 90° from the state illustrated in FIGS. 1A and 1B to allow optical axes thereof to be oriented toward the direction orthogonal to the z axis. However, in such a case, it is necessary to provide an optical device (for example, a mirror) guiding light output from the optical path combining device 30 toward the integrator 40 .

Light Sources 10 A, 10 B, 10 C Including Chips 11 A of Top Emission Type

For example, as illustrated in FIGS. 3A , 3 B, 4 A, and 4 B, each of the light sources 10 A, 10 B, and 10 C includes a solid-state light-emitting device 11 and a package 12 supporting the solid-state light-emitting device 11 (serving a base for mounting the solid-state light-emitting device 11 thereon). In other words, in this case, each of the light sources 10 A, 10 B, and 10 C is formed in a manner of a package in which the solid-state light-emitting device 11 is supported on the base. The solid-state light-emitting device 11 emits light from a light emission region including one or more dot-shaped or non-dot-shaped light-emitting spots. For example, as illustrated in FIGS. 3A and 3B , the solid-state light-emitting device 11 may include a single chip 11 A emitting light in a predetermined wavelength range, or as illustrated in FIGS. 4A and 4B , the solid-state light-emitting device 11 may include a plurality of chips 11 A emitting light in a same wavelength range or light in wavelength ranges different from one another. In the case where the solid-state light-emitting device 11 includes a plurality of chips 11 A, these chips 11 A may be arranged, for example, in a line in the transverse direction or the longitudinal direction as illustrated in FIGS. 4A and 4B , or in a grid-like pattern in the transverse direction and the longitudinal direction. The number of chips 11 A included in the solid-state light-emitting device 11 may be different in each of the light sources 10 A, 10 B, and 10 C, or may be the same in all of the light sources 10 A, 10 B, and 10 C.

In the case where the solid-state light-emitting device 11 includes the single chip 11 A, for example, as illustrated in FIG. 3A , a size (W V ×W H ) of the solid-state light-emitting device 11 is equal to a size (W V1 ×W H1 ) of the single chip 11 A. On the other hand, in the case where the solid-state light-emitting device 11 includes a plurality of chips 11 A, for example, as illustrated in FIG. 4A , the size of the solid-state light-emitting device 11 is equal to the size of a package into which all of the chips 11 A are gathered. In the case where the plurality of chips 11 A are arranged in a line in the longitudinal direction, the size (W V ×W H ) of the solid-state light-emitting device 11 is equal to W H1 ×2W V1 in an example in FIG. 4A . Moreover, in the case where the plurality of chips 11 A are arranged in a grid-like pattern in the transverse direction and the longitudinal direction, the size (W V ×W H ) of the solid-state light-emitting device 11 is equal to 2W V1 ×2W H1 .

Each of the chips 11 A is configured of a light-emitting diode (LED), an organic EL light-emitting diode (OLED), or a laser diode (LD). However, in the embodiment, the chip(s) 11 A included in one or two of the light sources 10 A, 10 B, and 10 C may be configured of an LD. It is to be noted that the chip(s) 11 A included in the other light source(s) may be configured of any of an LED, an OLED, and an LD.

The chips 11 A included in the light sources 10 A, 10 B, and 10 C emit light in wavelength ranges different in each of the light sources 10 A, 10 B, and 10 C, for example. The chip 11 A included in the light source 10 A emits, for example, light in a wavelength of about 500 nm to about 600 nm both inclusive (green light). The chip 11 A included in the light source 10 B emits, for example, light in a wavelength of about 400 nm to about 500 nm both inclusive (blue light). The chip 11 A included in the light source 10 C emits, for example, light in a wavelength of about 600 nm to about 700 nm both inclusive (red light). It is to be noted that the chip 11 A included in the light source 10 A may emit light (blue light or red light) other than green light. Moreover, the chip 11 A included in the light source 10 B may emit light (green light or red light) other than blue light. Further, the chip 11 A included in the light source 10 C may emit light (green light or blue light) other than red light.

For example, as illustrated in FIGS. 3A and 3B to FIGS. 5A and 5B , each of the chips 11 A has a light-emitting spot 11 B with a smaller size (P V1 ×P H1 ) than the size (W V ×W H ) of the chip 11 A. The light-emitting spot 11 B corresponds to a region (a light emission region) from which the chip 11 A emits light when a current is injected into the chip 11 A to drive the chip 11 A. In the case where the chip 11 A is configured of an LED or an OLED, the light-emitting spot 11 B has a non-dot (planar) shape, but in the case where the chip 11 A is configured of an LD, the light-emitting spot 11 B has a smaller dot shape than the light-emitting spot 11 B of the LED or the OLED.

In the case where the solid-state light-emitting device 11 includes a single chip 11 A, for example, as illustrated in FIG. 5A , the number of light-emitting spots 11 B is one. However, as will be described later, in the case where the solid-state light-emitting device 11 has a monolithic configuration, the number of light-emitting spots 11 B is two or more, and this applies to the following description. On the other hand, in the case where the solid-state light-emitting device 11 includes a plurality of chips 11 A, for example, as illustrated in FIG. 5B , the number of the light-emitting spots 11 B is equal to the number of chips 11 A (however, as described above, the solid-state light-emitting device 11 has a monolithic configuration, the number of light-emitting spots 11 B is larger than the number of chips 11 A). In the case where the solid-state light-emitting device 11 includes the single chip 11 A, a size (P V ×P H ) of the light emission region of the solid-state light-emitting device 11 is equal to the size (P V1 ×P H1 ) of the light-emitting spot 11 B (except for the case where the solid-state light-emitting device 11 has a monolithic configuration, as described above). On the other hand, in the case where the solid-state light-emitting device 11 includes a plurality of chips 11 A, the size (P V ×P H ) of the light emission region of the solid-state light-emitting device 11 is equal to a size of a smallest possible enclosure containing the light-emitting spots 11 B of all of the chips 11 A. In the case where the plurality of chips 11 A are arranged in a line in the longitudinal direction, in an example in FIG. 5B , the size (P V ×P H ) of the light emission region is larger than P H1 ×2P V1 , and is smaller than W V ×W H . Moreover, in the case where the plurality of chips 11 A are arranged in a grid-like pattern in the transverse direction and the longitudinal direction, the size (P V ×P H ) of the light emission region is larger than 2P V1 ×2P H1 , and is smaller than W V ×W H .

Light Sources 10 A, 10 B, and 10 C Including Chips 11 A of Edge-Emission Type

In FIGS. 3A and 3B to 5 A and 5 B, the case where the chips 11 A are of a top-emission type is described as an example; however, the chips 11 A may be of an edge-emission type which will be described later. In this case, for example, as illustrated in FIGS. 6A and 6B to 8 A to 8 C, the light sources 10 A, 10 B, and 10 C each are of a can type in which the solid-state light-emitting device 11 including one or a plurality of edge-emission type chips 11 A is contained in an inner space enclosed with a stem 13 and a cap 14 . In other words, in this case, each of the light sources 10 A, 10 B, and 10 C is formed in a manner of a package incorporating the solid-state light-emitting device 11 .

The stem 13 configures, together with the cap 14 , a package of each of the light sources 10 A, 10 B, and 10 C, and includes, for example, a supporting substrate 13 A supporting a submount 15 , an outer frame substrate 13 B disposed on a back side of the supporting substrate 13 A, and a plurality of connection terminals 13 C.

The submount 15 is made of a material having conductivity and thermal dissipation. The supporting substrate 13 A and the outer frame substrate 13 B each are configured of a base having conductivity and heat dissipation in which one or more insulating through holes and one or more conductive through holes are formed. The supporting substrate 13 A and the outer frame substrate 13 B each may have, for example, a disk shape, and are laminated to allow central axes (not illustrated) thereof to be superimposed on each other. A diameter of the outer frame substrate 13 B is larger than that of the supporting substrate 13 A. An outer edge of the outer frame substrate 13 B is a ring-shaped flange hanging over in a radiation direction from the central axis of the outer frame substrate 13 B in a plane having a normal along the central axis of the outer frame substrate 13 B. The flange has a role in determining a reference position when the cap 14 is fit into the supporting substrate 13 A in a manufacturing process.

The plurality of connection terminals 13 C penetrate through at least the supporting substrate 13 A. Terminals (hereinafter referred to as “terminals α” for convenience sake) except for one or more terminals of the plurality of connection terminals 13 C are electrically connected to respective electrodes (not illustrated) of the chips 11 A. For example, the terminals α protrude long on the outer frame substrate 13 B side, and protrude short on the supporting substrate 13 A side. Moreover, a terminal (hereinafter referred to as “terminal β” for convenience sake) other than the above-described terminals α of the plurality of connection terminals 13 C is electrically connected to the other electrodes (not illustrated) of all of the chips 11 A. For example, the terminal β protrudes long on the outer frame substrate 13 B side, and, for example, an end located closer to the supporting substrate 13 A of the terminal β is embedded in the supporting substrate 13 A. A portion protruding long on the outer frame substrate 13 side of each of the connection terminals 13 C corresponds to a portion fit in, for example, a substrate or the like. On the other hand, portions protruding short on the supporting substrate 13 A side of the plurality of connection terminals 13 C correspond to portions electrically connected to the respective chips 11 A through wires 16 . Portions embedded in the supporting substrate 13 A of the plurality of connection terminals 13 C correspond to, for example, portions electrically connected to all of the chips 11 A through the supporting substrate 13 and the submount 15 . The terminals α are supported by the insulating through holes formed in the supporting substrate 13 A and the outer frame substrate 13 B, and are insulated and separated from the supporting substrate 13 A and the outer frame substrate 13 B by the through holes. Moreover, the terminals α are insulated and separated from one another by the above-described insulating members. On the other hand, the terminal β is supported by the conductive through holes formed in the supporting substrate 13 A and the outer frame substrate 13 B, and is electrically connected to the through holes.

The cap 14 seals the solid-state light-emitting device 11 . The cap 14 has, for example, a cylindrical section 14 A having openings in upper and lower ends thereof. The lower end of the cylindrical section 14 A is in contact with, for example, a side surface of the supporting substrate 13 A, and the solid-state light-emitting device 11 is disposed in an inner space of the cylindrical section 14 A. The cap 14 has a light transmission window 14 B which is so disposed as to block the opening on the upper end of the cylindrical section 14 A. The light transmission window 14 B is disposed in a position facing a light emission surface of the solid-state light-emitting device 11 , and has a function of allowing light output from the solid-state light-emitting device 11 to pass therethrough.

Thus, also in the case where the chip 11 A is of an edge-emission type, the solid-state light-emitting device 11 emits light from the light emission region including one or more dot-shaped or non-dot-shaped light-emitting spots. The solid-state light-emitting device 11 may include, for example, a single chip 11 A emitting light in a predetermined wavelength range, or a plurality of chips 11 A emitting light in a same wavelength range or light in wavelength ranges different from one another. In the case where the solid-state light-emitting device 11 includes a plurality of chips 11 A, for example, as illustrated in FIGS. 6A , 6 B, 7 A, and 7 B, these chips 11 A may be arranged in a line in the longitudinal direction, or may be arranged, for example, in a line in the transverse direction. The number of chips 11 A included in the solid-state light-emitting device 11 may be different in each of the light sources 10 A, 10 B, and 10 C, or may be the same in all of the light sources 10 A, 10 B, and 10 C.

In the case where the solid-state light-emitting device 11 includes the single chip 11 A, for example, as illustrated in FIG. 8B , the size (W V ×W H ) of the solid-state light-emitting device 11 is equal to the size (W V1 ×W H1 ) of the single chip 11 A. However, for example, as illustrated in FIG. 8C , in the case where the solid-state light-emitting device 1 has a monolithic configuration, the size (W V ×W H ) of the solid-state light-emitting device 11 is larger than W H1 ×2W V1 , and this applies to the following description. On the other hand, in the case where the solid-state light-emitting device 11 includes a plurality of chips 11 A, for example, as illustrated in FIGS. 6B and 7B , the size of the solid-state light-emitting device 11 is equal to the size of a package into which all of the chips 11 A are gathered. In the case where the plurality of chips 11 A are arranged in a line in the longitudinal direction, the size (W V ×W H ) of the solid-state light-emitting device 11 is larger than W H1 ×3W V1 in an example in FIG. 6B , and is larger than W H1 ×2W V1 in an example in FIG. 7B . Moreover, in the case where the plurality of chips 11 A are arranged in a line in the transverse direction, for example, the size (W V ×W H ) of the solid-state light-emitting device 11 may be larger than 3W H1 ×W V1 or may be larger than 2W H1 ×W V1 .

Each of the chips 11 A may be configured of, for example, a laser diode (LD). However, also in this case, as described above, the chip(s) 11 A included in one or two of the light sources 10 A, 10 B, and 10 C may be configured of an LD. Moreover, the chip(s) 11 A included in the other light source(s) may be configured of any of an LED, an OLED, and an LD.

For example, as illustrated in FIGS. 6A and 6B to 8 A to 8 C, each of the chips 11 A has a light-emitting spot 11 B with a smaller size (P V1 ×P H1 ) than the size (W V ×W H ) of the chip 11 A. The light-emitting spot 11 B corresponds to a region (a light emission region) from which the chip 11 A emits light when a current is injected into the chip 11 A to drive the chip 11 A. In the case where the chip 11 A is configured of an LD, the light-emitting spot 11 B has a smaller dot shape than the light-emitting spot 11 B of the LED or the OLED.

In the case where the solid-state light-emitting device 11 includes a single chip 11 A, for example, as illustrated in FIG. 8B , the number of light-emitting spots 11 B is one. However, for example, as illustrated in FIG. 8C , in the case where the solid-state light-emitting device 11 has a monolithic configuration, the number of light-emitting spots 11 B is two or more (two in this case), and this applies to the following description. On the other hand, in the case where the solid-state light-emitting device 11 includes a plurality of chips 11 A, for example, as illustrated in FIGS. 6B , 7 B, and 8 B, the number of the light-emitting spots 11 B is equal to the number of chips 11 A. In this case, in the case where the solid-state light-emitting device 11 includes the single chip 11 A, the size (P V ×P H ) of the light emission region of the solid-state light-emitting device 11 is equal to the size (P V1 ×P H1 ) of the light-emitting spot 11 B. However, for example, as illustrated in an example in FIG. 8C , in the case where the solid-state light-emitting device 11 has a monolithic configuration, the size (P V ×P H ) of the light emission region of the solid-state light-emitting device 11 is larger than P H1 ×2P V1 , and is smaller than W V ×W H , and this applies the following description. On the other hand, in the case where the solid-state light-emitting device 11 includes a plurality of chips 11 A, the size (P V ×P H ) of the light emission region of the solid-state light-emitting device 11 is equal to the size of a smallest possible enclosure containing the light-emitting spots 11 B of all of the chips 11 A. In the case where the plurality of chips 11 A are arranged in a line in the longitudinal direction, in an example in FIG. 6B , the size (P V ×P H ) of the light emission region is larger than P H1 ×3P V1 , and is smaller than W V ×W H . Likewise, in an example in FIG. 7B , the size (P V ×P H ) of the light emission region is larger than P H1 ×2P V1 , and is smaller than W V ×W H . Moreover, in the case where the plurality of chips 11 A are arranged in a line in the transverse direction, the size (P V ×P H ) of the light emission region is larger than 3P H1 ×P V1 , and is smaller than W V ×W H .

Coupling Lenses 20 A, 20 B, and 20 C

For example, as illustrated in FIGS. 2A and 2B , the coupling lens 20 A converts light emitted from the light source 10 A into substantially parallel light, and changes a directivity angle of the light emitted from the light source 10 A to be equal to or close to a directivity angle of parallel light. The coupling lens 20 A is disposed in a position where light within the directivity angle of the light emitted from the light source 10 A enters. For example, as illustrated in FIGS. 2A and 2B , the coupling lens 20 B converts light emitted from the light source 10 B into substantially parallel light, and changes a directivity angle of the light emitted from the light source 10 B to be equal to or close to the directivity angle of parallel light. The coupling lens 20 B is disposed in a position where light within the directivity angle of the light emitted from the light source 10 B enters. For example, as illustrated in FIGS. 2A and 2B , the coupling lens 20 C converts light emitted from the light source 10 C into substantially parallel light, and changes a directivity angle of the light emitted from the light source 10 C to be equal to or close to the directivity angle of parallel light. The coupling lens 20 C is disposed in a position where light within the directivity angle of the light emitted from the light source 10 C enters. In other words, the coupling lenses 20 A, 20 B, and 20 C are disposed for the light sources 10 A, 10 B, and 10 C, respectively (for respective packages). It is to be noted that each of the coupling lenses 20 A, 20 B, and 20 C may be configured of a single lens, or a plurality of lenses.

Each of the dichroic mirrors 30 A and 30 B includes one mirror having wavelength selectivity. It is to be noted that, for example, the above-described mirror is formed through evaporating a multilayer interference film. For example, as illustrated in FIGS. 2A and 2B , the dichroic mirror 30 A allows light incident from a back side of the mirror (light incident from the light source 10 A) to pass toward a front side of the mirror, and reflects light incident from the front side of the mirror (light incident from the light source 10 B) by the mirror. On the other hand, as illustrated in FIGS. 2A and 2B , the dichroic mirror 30 B allows light incident from a back side of the mirror (light of the light sources 10 A and 10 B incident from the dichroic mirror 30 A) to pass to a front side of the mirror, and reflects light incident from the front side of the mirror (light incident from the light source 10 C) by the mirror. Therefore, the optical path combining device 30 combines respective light fluxes emitted from the light sources 10 A, 10 B, and 10 C into a single light flux.

For example, as illustrated in FIGS. 9A and 9B , the fly-eye lenses 40 A and 40 B are configured of a plurality of cells 41 (unit cells) and a plurality of cells 42 (unit cells), respectively. The plurality of cells 41 and the plurality of cells 42 are a plurality of lenses arranged in a predetermined arrangement (in this case, a matrix of 5 (vertical)×5 (horizontal)). In other words, the cells 41 in the fly-eye lens 40 A and the cells 42 in the fly-eye lens 40 B are arranged along respective arrangement directions, that is, the transverse direction (the x-axis direction) and the longitudinal direction (the y-axis direction) orthogonal to each other. The respective cells 42 included in the fly-eye lens 40 B are so arranged as to face the respective cells 41 of the fly-eye lens 40 A. The fly-eye lens 40 A is disposed in a focal position (or a substantial focal position) of the fly-eye lens 40 B, and the fly-eye lens 40 B is disposed in a focal position (or a substantial focal position) of the fly-eye lens 40 A. Therefore, the integrator 40 allows light fluxes formed through separating the single light flux by the fly-eye lens 40 A to be focused on proximity to a lens plane on an image side of the fly-eye lens 40 B, thereby forming a secondary light source plane (a light source image) thereon. The secondary light source plane is located on a plane conjugate to an entrance pupil of the projection optical system 70 . However, the secondary light source plane is not necessarily precisely located on the plane conjugate to the entrance pupil of the projection optical system 70 , and may be located within a design allowable region. It is to be noted that the fly-eye lenses 40 A and 40 B may be integrally formed as one unit.

In general, each of light fluxes emitted from the light sources 10 A, 10 B, and 10 C have a nonuniform intensity distribution (luminance distribution) on a plane perpendicular to a traveling direction thereof. Therefore, when these light fluxes are directly guided to the illumination region 60 A (the illuminated surface), an illuminance distribution (a luminance distribution) in the illumination region 60 A becomes nonuniform. On the other hand, as described above, when light fluxes emitted from the light sources 10 A, 10 B, and 10 C are separated by the integrator 40 into a plurality of light fluxes, and the plurality of light fluxes are guided to the illumination region 60 A in a superimposed manner, the illuminance distribution on the illumination region 60 A is allowed to become uniform (nonuniformity of the illumination distribution is allowed to be reduced).

The condenser lens 50 condenses the light fluxes, from light sources, formed by the integrator 40 to illuminate the illumination region 60 A with the light fluxes in a superimposed manner.

The spatial modulating device 60 two-dimensionally modulates light fluxes from the illumination optical system 1 A based on color image signals corresponding to respective wavelength components of the light sources 10 A, 10 B, and 10 C to generate image light. For example, as illustrated in FIGS. 2A and 2B , the spatial modulating device 60 is a transmissive device, and may be configured of, for example, a transmissive liquid crystal panel.

Configuration of Characteristic Part of Projector 1

Next, a characteristic part of the projector 1 according to the embodiment will be described below.

First, in the embodiment, the solid-state light-emitting device 11 having a light emission region which includes a plurality of light-emitting spots 11 B arranged along a predetermined direction (in the longitudinal direction (the y-axis direction) in this case) is provided to one (in particular, the light source 10 A in this case) or more of the light sources 10 A, 10 B, and 10 C. More specifically, in this case, as illustrated in FIGS. 2A and 2B , the solid-state light-emitting device 11 in the light source 10 A has two light-emitting spots 11 B arranged along the y-axis direction. It is to be noted that, as described above, a plurality of light-emitting spots 11 B may be provided by a plurality of chips 11 A or by a single chip 11 A with a monolithic configuration. In the solid-state light-emitting device 11 having such light-emitting spots 11 B, the chip 11 A includes an LD (a semiconductor laser or the like).

Moreover, in the embodiment, as described above, as optical members allowing light incident from the solid-state light-emitting device 11 to pass therethrough and exit therefrom, the coupling lenses 20 A, 20 B, and 20 C changing a directivity angle of light incident from the solid-state light-emitting device 11 are provided. As described above, a coupling lens (the coupling lens 20 A in this case) where laser light emitted from the solid-state light-emitting device 11 having a plurality of light-emitting spots 11 B enters of the coupling lenses 20 A, 20 B, and 20 C is so configured as to have a lens effect exhibiting the following function. In other words, for example, as illustrated in FIGS. 2A and 2B , the coupling lens is so configured as to have a smaller lens effect along the above-described predetermined direction (an arrangement direction of the plurality of light-emitting spots 11 B; the y-axis direction) than a lens effect along a direction (the x-axis direction) orthogonal to the predetermined direction in the light emission region of the solid-state light-emitting device 11 . It is to be noted that the lens effect in the coupling lens 20 A in this case refers to divergent or convergent refractive power of a lens for being optically coupled with an optical system following the coupling lens (the optical path combining device 30 , the integrator 40 , and the like in this case).

In the embodiment, more specifically, to achieve such a lens effect, the coupling lens 20 A has a lens configuration illustrated in FIGS. 1A , 1 B, 2 A, and 2 B. In other words, the coupling lens 20 A includes one or more cylindrical lenses not having a lens effect along the above-described arrangement direction (the y-axis direction) of the plurality of light-emitting spots. More specifically, in this case, the coupling lens 20 A includes a cylindrical lens 21 A (a first cylindrical lens) which is located closer to the light source 10 A (in a preceding stage) and is a concave lens and a cylindrical lens 22 A (a second cylindrical lens) which is located closer to the dichroic mirror 30 A (in a following state) and is a convex lens. For example, as illustrated in FIGS. 2A and 2B , the cylindrical lens 21 A is a lens having a function of expanding a diameter of incident laser light (a light flux diameter). On the other hand, the cylindrical lens 22 A is a lens having a function of converting laser light with a diameter expanded by the cylindrical lens 21 A into a substantially parallel light beam in a plane (a z-x plane) orthogonal to the arrangement direction of the light-emitting spots 11 B and then emitting the substantially parallel light beam. With such a configuration, the entire coupling lens 20 A changes a directivity angle of incident laser light to convert the laser light into a substantially parallel light beam in the plane (the z-x plane) orthogonal to the arrangement direction of the light-emitting spots 11 B and then to emit the substantially parallel light beam.

It is to be noted that, unlike the coupling lens 20 A with such a configuration, each of the coupling lenses 20 B and 20 C is configured of one spherical lens which is a convex lens.

Functions and Effects of Projector 1

Next, functions and effects of the projector 1 according to the embodiment will be described below.

First, in the embodiment, the solid-state light-emitting device 11 having a light emission region which includes a plurality of light-emitting spots 11 B arranged along the predetermined direction (the y-axis direction) is included in the light source 10 A. In the solid-state light-emitting device 11 having the plurality of light-emitting spots 11 B, the chip 11 A includes an LD. Therefore, output of laser light is increased with a simple configuration, and higher luminance of illumination light is achieved. In other words, to achieve an increase in output of laser light with a single light-emission spot 11 B, for example, it is necessary to increase light emission efficiency of a semiconductor or light extraction efficiency; therefore, it is technically highly difficult. On the other hand, when a plurality of light-emitting spots 11 B are used in combination, an increase in output of laser light is achieved with a simple configuration.

Moreover, in the embodiment, as optical members allowing light incident from the solid-state light-emitting device 11 to pass therethrough and exit therefrom, the coupling lenses 20 A, 20 B, and 20 C changing the directivity angle of light incident from the solid-state light-emitting device 11 are provided. Therefore, use efficiency (light use efficiency) of light emitted from the light sources 10 A, 10 B, and 10 C is improved.

Function of Coupling Lens 20 A

Moreover, in the embodiment, the coupling lens 20 A where laser light emitted from the solid-state light-emitting device 11 having a plurality of light-emitting spots 11 B enters is so configured as to have a lens effect exhibiting the following lens function. In other words, for example, as illustrated in FIGS. 2A and 2B , the coupling lens 20 A is so configured as to have a smaller lens effect along the above-described predetermined direction (an arrangement direction of the plurality of light-emitting spots 11 B; the y-axis direction) than a lens effect along the direction (the x-axis direction) orthogonal to the predetermined direction in the light emission region of the solid-state light-emitting device 11 . Thus, it is only necessary for the coupling lens 20 A to have a relatively small lens effect along the arrangement direction of the plurality of light-emitting spots 11 B (it is not necessary to produce the lens effect in this case); therefore, light use efficiency is improved while achieving simplification (downsizing) of a configuration of an optical member (the coupling lens 20 A).

More specifically, for example, it is not necessary to separately provide a cylindrical lens along the arrangement direction of the plurality of light-emitting spots 11 B and a cylindrical lens along the direction orthogonal to the arrangement direction; therefore, simplification (downsizing) of the configuration of the coupling lens 20 A is achievable. Moreover, when light is allowed to enter the integrator 40 , for example, with an LD having an extremely small divergent angle, it is necessary for an optical system to have an optical path long enough to make a light flux sufficiently large on the integrator 40 , and the optical system becomes extremely large accordingly. On the other hand, in the embodiment, since the coupling lens 20 A with the above-described configuration is used, it is not necessary for the optical system to have an optical path long enough to make the light flux incident on the integrator 40 sufficiently large; therefore, downsizing is easily achieved.

Function of Integrator 40

Moreover, at this time, in the embodiment, for example, as illustrated in FIGS. 10 and 11 , luminance distribution regions with the following shape are formed on a light incident plane of the integrator 40 (the fly-eye lens 40 A) by light fluxes incident from the coupling lens 20 A. In other words, a plurality of luminance distribution regions Lind corresponding to respective light-emitting spots 11 B are separately formed along the arrangement direction (the y-axis direction) of the plurality of light-emitting spots 11 B. More specifically, in this case, each of the luminance distribution regions Lind has an anisotropic shape having a minor-axis direction along the arrangement direction (the y-axis direction) of the plurality of light-emitting spots 11 B and a major-axis direction along the direction (the x-axis direction) orthogonal to the arrangement direction by anisotropy of the lens effect in the above-described coupling lens 20 A.

In this case, in the integrator 40 in the embodiment, for example, as illustrated in FIG. 11 , the following expressions (1) and (2) are preferably satisfied in relation to sizes of light fluxes forming the respective luminance distribution regions Lind and an effective size in the light incident plane of the fly-eye lens 40 A. It is to be noted that, in this case, a light flux size is determined by a length of a luminance region with intensity (luminance) of (1/e 2 ) or over in an incident light flux onto the fly-eye lens 40 A. When these expressions (1) and (2) are satisfied, laser light emitted from the plurality of light-emitting spots 11 B in the light source 10 A is allowed to reach the integrator 40 (the fly-eye lens 40 A) without causing light loss, thereby further improving light use efficiency. Moreover, for example, in the case where a divergent angle (a beam spread angle along the y-axis direction) of the light source 10 A itself falls in an allowable angle of the integrator 40 , light is allowed to be guided to the illumination region 60 A without causing light loss.

φ x≧φkx   (1)

φ y ≧(φ ly/ 2)+(φ ny/ 2)+ d   (2)

where φx is an effective size of the integrator 40 along the direction (the x-axis direction) orthogonal to the arrangement direction of the plurality of light-emitting spots 11 B on the above-described light incident plane,

φy is an effective size of the integrator 40 along the arrangement direction (the y-axis direction) of the plurality of light-emitting spots 11 B on the above-described light incident plane,

φk is each of light fluxes forming the plurality of luminance distribution regions Lind, where k=1, 2, . . . , or n, and n is an integer of 2 or more,

φkx is a light flux size along the direction (the x-axis direction) orthogonal to the arrangement direction of the plurality of light-emitting spots 11 B of the light flux φk,

φly is a light flux size along the arrangement direction (the y-axis direction) of the plurality of light-emitting spots 11 B in the light flux φl,

φny is a light flux size along the arrangement direction (the y-axis direction) of the plurality of light-emitting spots 11 B in the light flux φn, and d is a distance between centers of the light fluxes φl and φn along the arrangement direction (y-axis direction) of the plurality of light-emitting spot 11 B.

In the case where the above-described expressions (1) and (2) are satisfied, light use efficiency has, for example, about 90% or over. At this time, in particular, the light flux size φkx preferably satisfies the following expressions (3) and (4) or the following expressions (5) and (6). When the expressions (3) and (4) are satisfied, light use efficiency from the light source 10 A to the integrator 40 is, for example, higher than about 97%. Moreover, when the expressions (5) and (6) are satisfied, the light use efficiency from the light source 10 A to the integrator 40 is, for example, close to about 100%. In other words, a further improvement in light use efficiency is achieved.

0.77φ x>φkx   (3)

0.77φ y >(φ ly/ 2)+(φ ny/ 2)+ d   (4)

0.52φ x>φkx   (5)

0.52φ y >(φ ly/ 2)+(φ ny/ 2)+ d   (6)

Moreover, at this time, the following expression (7) or the following expression (8) is preferably satisfied in relation to the above-described light flux size φkx and a pitch p (a minimum pitch) of a unit cell (a cell 41 ) in the integrator 40 (the fly-eye lens 40 A). It is to be noted that, when the cell 41 has, for example, a rectangular shape, the pitch p of the cell 41 is determined, for example, as illustrated in FIG. 12A , and when the cell 41 has, for example, a hexagonal shape, the pitch p of the cell 41 is determined, for example, as illustrated in FIG. 12B . In the case where the expression (7) or (8) is satisfied in such a manner, a sufficient number of light fluxes superimposed on one another are secured in the integrator 40 ; therefore, an illumination image with high luminance uniformity is obtainable. Moreover, in particular, when the expression (8) is satisfied, luminance uniformity is further improved. It is to be noted that FIGS. 13A to 13C illustrate examples of the shape of the luminance distribution region Lind (in the case where the cell 41 has a rectangular shape) in the case of φkx>4.3p ( FIG. 13A ), φkx>2.3p ( FIG. 13B ), and φkx>1.6p ( FIG. 13C ). FIGS. 13A to 13C provides that as the light flux size φkx is relatively increased with respect to the pitch p of the cell 41 , an effective number of light fluxes superimposed on one another in the integrator 40 is increased to improve luminance uniformity.

φ kx> 2.3 p   (7)

φ kx> 4.3 p   (8)

As described above, in the embodiment, in the solid-state light-emitting device 11 having the plurality of light-emitting spots 11 B, the chip 11 A includes an LD, and the coupling lenses 20 A and 20 B changing the directivity angle of light incident from the solid-state light-emitting device 11 are included; therefore, light use efficiency is improvable while achieving higher luminance of illumination light. Moreover, in the coupling lens 20 A where laser light emitted from the solid-state light-emitting device 11 having the plurality of light-emitting spots 11 B enters, the lens effect along the predetermined direction (the arrangement direction of the plurality of light-emitting spots 11 B) is smaller than the lens effect along the direction orthogonal to the above-described predetermined direction in the light emission region; therefore, light use efficiency is improvable while achieving simplification (downsizing) of the configuration. Therefore, light use efficiency is improvable with a simple configuration while achieving higher luminance of illumination light, and display image quality is also improvable. In other words, a laser projector with higher luminance and lower power consumption capable of being mounted in a small and lightweight electronic apparatus is achievable.

Modifications

Next, modifications (Modifications 1 to 5) of the above-described embodiment will be described below. It is to be noted that like components are denoted by like numerals as of the embodiment and will not be further described.

Modification 1

FIGS. 14A and 14B illustrate an example of a schematic configuration of a projector (a projector 3 ) and optical paths according to Modification 1. It is to be noted that the projector 3 corresponds to a specific example of “projection display unit” in an embodiment of the disclosure. FIG. 14A illustrates a configuration example of the projector 3 and an example of the optical paths when the projector 3 is viewed from above (from the y-axis direction), and FIG. 14B illustrates a configuration example of the projector 3 and an example of the optical paths when the projector 3 is viewed from a side thereof (from the x-axis direction).

The projector 3 according to the present modification is different from the projector 1 including the illumination optical system 1 A in that the projector 3 includes an illumination optical system 3 A. Description will be given of, mainly, points different from the projector 1 , and points common to the projector 1 will not be further described. It is to be noted that the illumination optical system 3 A corresponds to a specific example of “illumination unit” in an embodiment of the disclosure.

The illumination optical system 3 A corresponds to the illumination optical system 1 A in which the lens configuration of the coupling lens 20 A is modified. More specifically, as with the coupling lens 20 A in the illumination optical system 1 A, the coupling lens 20 A in the illumination optical system 3 A includes one or more cylindrical lenses not having the lens effect along the arrangement direction (the y-axis direction) of the plurality of light-emitting spots. More specifically, in this case, the coupling lens 20 A includes the cylindrical lens 21 A which is located closer to the light source 10 A (in a preceding stage) and is a concave lens and an anamorphic lens 23 A which is located closer to the dichroic mirror 30 A (in a following stage) and is a convex lens. In other words, the coupling lens 20 A in the illumination optical system 3 A has a configuration in which the anamorphic lens 23 A is included instead of the cylindrical lens 22 A in the coupling lens 20 A of the illumination optical system 1 A.

As described above, the cylindrical lens 21 A is a lens having a function of expanding the diameter of incident laser light (the light flux diameter). On the other hand, as with the above-described cylindrical lens 22 A, the anamorphic lens 23 A is a lens having a function of converting laser light with a diameter expanded by the cylindrical lens 21 A into a substantially parallel light beam in the plane (the z-x plane) orthogonal to the arrangement direction of the light-emitting spots 11 B and then emitting the substantially parallel light beam. However, unlike the cylindrical lens 22 A, for example, as illustrated in FIG. 14B , the anamorphic lens 23 A has a slight lens effect along the arrangement direction (the y-axis direction) of the light-emitting spots 11 B. However, in the entire coupling lens 20 A, the lens effect along the arrangement direction (the y-axis direction) of the plurality of light-emitting spots 11 B is smaller than the lens effect along the direction (the x-axis direction) orthogonal to the above-described predetermined direction in the light emission region. With such a configuration, the entire coupling lens 20 A in the present modification also changes the directivity angle of incident laser light to convert the laser light into a substantially parallel light beam in the plane (the z-x plane) orthogonal to the arrangement direction of the light-emitting spots 11 B and then to emit the substantially parallel light beam.

Also in the projector 3 according to the present modification including the coupling lens 20 A with such a configuration, effects similar to those in the projector 1 according to the above-described embodiment are obtainable by functions similar to those in the projector 1 .

Modification 2

FIGS. 15A and 15B illustrate an example of a schematic configuration of a projector (a projector 4 ) and optical paths according to Modification 2. It is to be noted that the projector 4 corresponds to a specific example of “projection display unit” in an embodiment of the disclosure. FIG. 15A illustrates a configuration example of the projector 4 and an example of the optical paths when the projector 4 is viewed from above (from the y-axis direction), and FIG. 15B illustrates a configuration example of the projector 4 and an example of the optical paths when the projector 4 is viewed from a side thereof (from the x-axis direction).

The projector 4 according to the present modification is different from the projector 1 including the illumination optical system 1 A in that the projector 4 includes an illumination optical system 4 A. Description will be given of, mainly, points different from the projector 1 , and points common to the projector 1 will not be further described. It is to be noted that the illumination optical system 4 A corresponds to a specific example of “illumination unit” in an embodiment of the disclosure.

The illumination optical system 4 A corresponds to the illumination optical system 1 A in which the lens configuration of the coupling lens 20 A is modified. More specifically, as with the coupling lens 20 A in the illumination optical system 1 A, the coupling lens 20 A in the illumination optical system 4 A includes one or more cylindrical lenses not having the lens effect along the arrangement direction (the y-axis direction) of the plurality of light-emitting spots. More specifically, in this case, the coupling lens 20 A includes a cylindrical lens 24 A which is located closer to the light source 10 A (in a preceding stage) and is a convex lens and the cylindrical lens 22 A which is located closer to the dichroic mirror 30 A (in a following stage) and is a convex lens. In other words, the coupling lens 20 A in the illumination optical system 4 A has a configuration in which the cylindrical lens 24 A configured of a convex lens is included instead of the cylindrical lens 21 A configured of a convex lens in the coupling lens 20 A of the illumination optical system 1 A, and the coupling lens 20 A in the illumination optical system 4 A uses two convex lenses.

As with the above-described cylindrical lens 21 A, the cylindrical lens 24 A is a lens having a function of expanding the diameter of incident laser light (the light flux diameter). With such a configuration, the entire coupling lens 20 A in the present modification also changes the directivity angle of incident laser light to convert the laser light into a substantially parallel light beam in the plane (the z-x plane) orthogonal to the arrangement direction of the light-emitting spots 11 B and then to emit the substantially parallel light beams. It is to be noted that, also in the entire coupling lens 20 A in the present modification, the lens effect along the arrangement direction (the y-axis direction) of the plurality of light-emitting spots 11 B is smaller than the lens effect along the direction (the x-axis direction) orthogonal to the above-described predetermined direction in the light emission region.

Also in the projector 4 according to the present modification including the coupling lens 20 A with such a configuration, effects similar to those in the projector 1 according to the above-described embodiment are obtainable by functions similar to those in the projector 1 .

Modification 3

FIGS. 16A and 16B illustrate an example of a schematic configuration of a projector (a projector 5 ) and optical paths according to Modification 3. It is to be noted that the projector 5 corresponds to a specific example of “projection display unit” in an embodiment of the disclosure. FIG. 16A illustrates a configuration example of the projector 5 and an example of the optical paths when the projector 5 is viewed from above (from the y-axis direction), and FIG. 16B illustrates a configuration example of the projector 5 and an example of the optical paths when the projector 5 is viewed from a side thereof (from the x-axis direction).

The projector 5 according to the present modification is different from the projector 1 including the illumination optical system 1 A in that the projector 5 includes an illumination optical system 5 A. Description will be given of, mainly, points different from the projector 1 , and points common to the projector 1 will not be further described. It is to be noted that the illumination optical system 5 A corresponds to a specific example of “illumination unit” in an embodiment of the disclosure.

The illumination optical system 5 A corresponds to the illumination optical system 1 A in which the lens configuration of the coupling lens 20 A is modified. More specifically, as with the coupling lens 20 A in the illumination optical system 1 A, the coupling lens 20 A in the illumination optical system 5 A includes one or more cylindrical lenses not having the lens effect along the arrangement direction (the y-axis direction) of the plurality of light-emitting spots. More specifically, in this case, the coupling lens 20 A includes the cylindrical lens 24 A which is a convex lens. In other words, the coupling lens 20 A in the present modification has a configuration using only one cylindrical lens 24 A which is a convex lens.

With such a configuration, unlike the above-described embodiment and Modifications 1 and 2, the present modification does not have a function of converting incident laser light into substantially parallel light (a function of changing a directivity angle). However, also in the entire coupling lens 20 A in the present modification, the lens effect along the arrangement direction (the y-axis direction) of the plurality of light-emitting spots 11 B is smaller than the lens effect along the direction (the x-axis direction) orthogonal to the above-described predetermine direction in the light emission region.

Also in the projector 5 according to the present modification including the coupling lens 20 A with such a configuration, effects similar to those in the projector 1 according to the above-described embodiment are obtainable by functions similar to those in the projector 1 .

Modification 4

FIGS. 17A and 17B illustrate an example of a schematic configuration of a projector (a projector 6 ) according to Modification 4. It is to be noted that the projector 6 corresponds to a specific example of “projection display unit” in an embodiment of the disclosure. FIG. 17A illustrates a configuration example of the projector 6 when viewed from above (from the y-axis direction), and FIG. 17B illustrates a configuration example of the projector 6 when viewed from a side thereof (from the x-axis direction).

The projector 6 according to the present modification is different from the projector 1 including the illumination optical system 1 A in that the projector 6 includes an illumination optical system 6 A and a reflective device is used as the spatial modulating device 60 . Description will be given of, mainly, points different from the projector 1 , and points common to the projector 1 will not be further described. It is to be noted that the illumination optical system 6 A corresponds to a specific example of “illumination unit” in an embodiment of the disclosure.

The illumination optical system 6 A corresponds to the illumination optical system 1 A in which a condenser lens 50 A is included instead of the condenser lens 50 . The condenser lens 50 A is a lens converting light fluxes, from light sources, formed by the integrator 40 into parallel light fluxes to illuminate a condenser lens 50 B with the light fluxes through a polarizing beam splitter 51 .

Moreover, in the present modification, as described above, the spatial modulating device 60 may be configured of, for example, a reflective device such as a reflective liquid crystal panel. Therefore, compared to the projector 1 , the projector 6 further includes the condenser lens 50 B and the polarizing beam splitter 51 . The polarizing beam splitter 51 is an optical member selectively allowing specific polarized light (for example, p-polarized light) to pass therethrough and selectively reflecting the other polarized light (for example, s-polarized light). Moreover, the spatial modulating device 60 performs light modulation while reflecting light to allow light incident thereon and light exiting therefrom to have different polarization states (for example, s-polarization and p-polarization). Therefore, light incident from the illumination optical system 6 A (for example, s-polarized light) is selectively reflected to enter the spatial modulating device 60 , and image light (for example, p-polarized light) emitted from spatial modulating device 60 selectively passes through the spatial modulating device 60 to enter the projection optical system 70 . The condenser lens 50 B is a lens condensing light fluxes, from light sources, formed by the integrator 40 and being incident thereon through the condenser lens 50 A and the polarizing beam splitter 51 to illuminate the illumination region 60 A with the light fluxes in a superimposed manner.

Also in the projector 6 according to the present modification having such a configuration, effects similar to those in the projector 1 according to the above-described embodiment are obtainable by functions similar to those in the projector 1 .

Modification 5

FIGS. 18A and 18B illustrate a schematic configuration of a projector (a projector 7 ) according to Modification 5. It is to be noted that the projector 7 corresponds to a specific example of “projection display unit” in an embodiment of the disclosure. FIG. 18A illustrates a configuration example of the projector 7 when viewed from above (from the y-axis direction), and FIG. 18B illustrates a configuration example of the projector 7 when viewed from a side thereof (from the x-axis direction).

The projector 7 according to the present modification is different from the projector 1 including the illumination optical system 1 A in that the projector 7 includes an illumination optical system 7 A. Description will be given of, mainly, points different from the projector 1 , and points common to the projector 1 will not be further described. It is to be noted that the illumination optical system 7 A corresponds to a specific example of “illumination unit” in an embodiment of the disclosure.

In the illumination optical system 7 A, unlike the illumination optical system 1 A (and the illumination optical systems 3 A, 4 A, 5 A, and 6 A) including a plurality of (three) light sources 10 A, 10 B, and 10 C, only one light source 10 A is included, and the dichroic mirrors 30 A and 30 B are not included. The light source 10 A is disposed on an optical axis of the coupling lens 20 A, and in the illumination optical system 7 A, light emitted from the light source 10 A directly enters the coupling lens 20 A.

Also in the projector 7 according to the present modification in which only one light source 10 A is included in the illumination optical system 1 A, effects similar to those in the projector 1 according to the above-described embodiment are obtainable by functions similar to those in the projector 1 .

Other Modifications

Although the technology of the present disclosure is described referring to the embodiments and the modifications, the technology is not limited thereto, and may be variously modified.

For example, in the above-described embodiment and the like, an example in which only the light source 10 A of the light sources 10 A, 10 B, and 10 C has a plurality of light-emitting spots 11 B is described; however, the technology is not limited thereto, and the light sources 10 B and 10 C may have a plurality of light-emitting spots 11 B in a manner similar to the light source 10 A. In this case, when the coupling lenses 20 B and 20 C have a configuration similar to that of the coupling lens 20 A described in the above-described embodiment and the like, similar effects are obtainable. Moreover, wavelengths of light emitted from the light sources 10 A, 10 B, and 10 C may be arbitrarily replaced with one another. Further, all of the light sources 10 A, 10 B, and 10 C may be contained in an integral package, and the integral package may have a configuration similar to that of the light source 10 A. In this case, when the configuration of the coupling lens 20 A described in the above-described embodiment and the like is adopted, similar effects are obtainable.

In the above-described embodiment and the like, each of the illumination optical systems 1 A, 3 A, 4 A, 5 A, 6 A, and 7 A includes an infinite optical system allowing parallel light to enter the fly-eye lens 40 A; however, each of them may include a finite optical system allowing convergent light (or divergent light) to enter the fly-eye lens 40 A. In this case, in the above-described embodiment and the like, instead of the coupling lenses 20 A to 20 C, coupling lenses (directivity angle change devices) having a function of converging (or diverging) light emitted from the light sources 10 A to 10 C may be provided.

A combination of any of configurations of characteristics parts in the respective illumination optical systems and the respective projectors described in the above-described embodiment and the like may be used. More specifically, a combination of the configuration of the illumination optical system 1 A in the embodiment and any of the illumination optical systems 3 A, 4 A, 5 A, 6 A, and 7 A in Modifications 1 to 5 may be used.

In the above-described embodiment and the like, a case where the technology is applied to the projection display unit is described; however, the technology is also applicable to any other display units. For example, as illustrated in FIG. 19 , the technology is applicable to a rear-projection display unit 9 (a direct-view display unit). The rear-projection display unit 9 includes any of the projectors 1 , 3 , 4 , 5 , 6 , 7 , and the like including any of the illumination optical systems 1 A, 3 A, 4 A, 5 A, 6 A, and 7 A (or a combination of any of them) and a transmissive screen 90 displaying image light projected from the projector 1 , 3 , 4 , 5 , 6 , 7 , or the like (the projection optical system 70 ). When the illumination optical system 1 A, 3 A, 4 A, 5 A, 6 A, 7 A, or the like is used as an illumination optical system of the rear-projection display unit 9 in such a manner, light use efficiency is improvable with a simple configuration while achieving higher luminance of illumination light (image light or display light), and display image quality is improvable.

In the above-described embodiment and the like, a case where the spatial modulating device 60 is configured of a transmissive or reflective device is described as an example; however, the technology is not limited thereto. Alternatively, the spatial modulating device 60 may be configured of, for example, a digital micromirror device (DMD).

In the technology, in the solid-state light-emitting device 11 having a plurality of light-emitting spots 11 B, the chip 11 A may be configured of an SHG (Second Harmonic Generation) laser including an LD and an optical crystal (a wavelength conversion crystal).

In the above-described embodiment and the like, respective components (optical systems) of the illumination optical system and the display unit are specifically described; however, it is not necessary to include all of the components, or other components may be further included.

In the above-described embodiment and the like, a case where the illumination units in the embodiments and the like of the disclosure are applied to the projection display unit or the like is described as an example; however, the technology is not limited thereto, and the illumination unit is applicable to, for example, exposure systems such as steppers.

It is to be noted that the technology may have the following confirmations.

(1) An illumination unit including:

one or more light sources each including a solid-state light-emitting device, the solid-state light-emitting device emitting light from a light emission region thereof, the light emission region including a plurality of light-emitting spots arranged along a predetermined direction; and

an optical member allowing light incident from the solid-state light-emitting device to pass therethrough and exit therefrom,

in which the optical member includes one or more coupling lenses changing a directivity angle of the light incident from the solid-state light-emitting device,

the solid-state light-emitting device includes a single chip or a plurality of chips, the single chip emitting light in a single wavelength range or light in a plurality of wavelength ranges, the plurality of chips emitting light in a same wavelength range or light in wavelength ranges different from one another,

the single chip or the plurality of chips in the solid-state light-emitting device having the plurality of light-emitting spots each include a laser diode, and

a first coupling lens of the one or more coupling lenses has a smaller lens effect along the predetermined direction than a lens effect along a direction orthogonal to the predetermined direction in the light emission region, the first coupling lens on which laser light emitted from the solid-state light-emitting device having the plurality of light-emitting spots is incident.

(2) The illumination unit according to (1), in which the first coupling lens includes one or more cylindrical lenses not having a lens effect along the predetermined direction.

(3) The illumination unit according to (2), in which the first coupling lens includes a first cylindrical lens and a second cylindrical lens, the first cylindrical lens and the second cylindrical lens being a concave lens and a convex lens, respectively.

(4) The illumination unit according to (3), in which

the first cylindrical lens expands a diameter of laser light incident thereon, and

the second cylindrical lens converts the laser light with a diameter expanded by the first cylindrical lens into a substantially parallel light beam in a plane orthogonal to the predetermined direction, and then emits the substantially parallel light beam.

(5) The illumination unit according to (2), in which the first coupling lens includes a cylindrical lens and an anamorphic lens, the cylindrical lens and the anamorphic lens being a concave lens and a convex lens, respectively.

(6) The illumination unit according to (2), in which the first coupling lens includes a plurality of cylindrical lenses which are convex lenses.

(7) The illumination unit according to any one of (2) to (6), in which the first coupling lens changes a directivity angle of incident laser light to convert the laser light into a substantially parallel light beam in a plane orthogonal to the predetermined direction, and then to emit the substantially parallel light beam.

(8) The illumination unit according to (2), in which the first coupling lens includes one cylindrical lens configured of a convex lens.

(9) The illumination unit according to any one of (1) to (8), in which the optical member includes the one or more coupling lenses, and an integrator uniformizing a luminance distribution in a predetermined illumination region illuminated with light having passed through the one or more coupling lenses.

(10) The illumination unit according to (9), in which a plurality of luminance distribution regions are separately formed along the predetermined direction on a light incident plane of the integrator by light fluxes incident from the one or more coupling lenses.

(11) The illumination unit according to (10), in which expressions [1] and [2] are satisfied in the integrator:

φ x≧φkx   [1]

φ y ≧(φ ly/ 2)+(φ ny/ 2)+ d   [2]

where φx is an effective size of the integrator along the direction orthogonal to the predetermined direction on the light incident plane,

φy is an effective size of the integrator along the predetermined direction on the light incident plane,

φk is each of light fluxes forming the plurality of luminance distribution regions, where k=1, 2, . . . , or n, and n is an integer of 2 or more,

φkx is a light flux size along the direction orthogonal to the predetermined direction in the light flux φk,

φly is a light flux size along the predetermined direction in the light flux φl,

φny is a light flux size along the predetermined direction in the light flux φn, and

d is a distance between centers of the light fluxes φl and φn along the predetermined direction.

(12) The illumination unit according to (10) or (11), in which

the integrator includes one or more fly-eye lenses each including a plurality of unit cells on the light incident plane, and

an expression [3] is satisfied:

φ kx> 2.3 p   [3]

where φk is each of light fluxes forming the plurality of luminance distribution regions, where k=1, 2, . . . , or n, and n is an integer of 2 or more,

φkx is a light flux size along the direction orthogonal to the predetermined direction, and

p is a pitch of the unit cell.

(13) The illumination unit according to any one of (1) to (11), in which the light source is formed in a manner of a package incorporating the solid-state light-emitting device or a package in which the solid-state light-emitting device is supported on a base.

(14) The illumination unit according to any one of (1) to (12), in which the single chip or the plurality of chips in the solid-state light-emitting device having the plurality of light-emitting spots each includes a second harmonic generation (SHG) laser including the laser diode and an optical crystal.

(15) A projection display unit provided with an illumination optical system, a spatial modulating device, and a projection optical system, the spatial modulating device modulating light from the illumination optical system based on an input image signal to generate image light, the projection optical system projecting the image light generated by the spatial modulating device, the illumination optical system including:

one or more light sources each including a solid-state light-emitting device, the solid-state light-emitting device emitting light from a light emission region thereof, the light emission region including a plurality of light-emitting spots arranged along a predetermined direction; and

an optical member allowing light incident from the solid-state light-emitting device to pass therethrough and exit therefrom,

in which the optical member includes one or more coupling lenses changing a directivity angle of the light incident from the solid-state light-emitting device,

the solid-state light-emitting device includes a single chip or a plurality of chips, the single chip emitting light in a single wavelength range or light in a plurality of wavelength ranges, the plurality of chips emitting light in a same wavelength range or light in wavelength ranges different from one another,

the single chip or the plurality of chips in the solid-state light-emitting device having the plurality of light-emitting spots each include a laser diode, and

a first coupling lens of the one or more coupling lenses has a smaller lens effect along the predetermined direction than a lens effect along a direction orthogonal to the predetermined direction in the light emission region, the first coupling lens on which laser light emitted from the solid-state light-emitting device having the plurality of light-emitting spots is incident.

(16) A direct-view display unit provided with an illumination optical system, a spatial modulating device, a projection optical system, and a transmissive screen, the spatial modulating device modulating light from the illumination optical system based on an input image signal to generate image light, the projection optical system projecting the image light generated by the spatial modulating device, the transmissive screen displaying the image light projected from the projection optical system, the illumination optical system including:

one or more light sources each including a solid-state light-emitting device, the solid-state light-emitting device emitting light from a light emission region thereof, the light emission region including a plurality of light-emitting spots arranged along a predetermined direction; and

an optical member allowing light incident from the solid-state light-emitting device to pass therethrough and exit therefrom,

in which the optical member includes one or more coupling lenses changing a directivity angle of the light incident from the solid-state light-emitting device,

the solid-state light-emitting device includes a single chip or a plurality of chips, the single chip emitting light in a single wavelength range or light in a plurality of wavelength ranges, the plurality of chips emitting light in a same wavelength range or light in wavelength ranges different from one another,

the single chip or the plurality of chips in the solid-state light-emitting device having the plurality of light-emitting spots each include a laser diode, and

a first coupling lens of the one or more coupling lenses has a smaller lens effect along the predetermined direction than a lens effect along a direction orthogonal to the predetermined direction in the light emission region, the first coupling lens on which laser light emitted from the solid-state light-emitting device having the plurality of light-emitting spots is incident.

It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present subject matter and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims.