Coupling light of light emitting resonator to waveguide

The present invention is related to and claims priority from U.S. application Ser. No. 11/302,471, entitled “Coupled Nano-Resonating Energy Emitting Structures,” filed Dec. 14, 2005 , the entire contents of which is incorporated herein by reference.

The present invention is related to the following co-pending U.S. patent applications, which are all commonly owned with the present application, the entire contents of each of which are incorporated herein by reference:

(1) U.S. patent application Ser. No. 11/238,991, filed Sep. 30, 2005, entitled “Ultra-Small Resonating Charged Particle Beam Modulator”; (2) U.S. patent application Ser. No. 10/917,511, filed on Aug. 13, 2004, entitled “Patterning Thin Metal Film by Dry Reactive Ion Etching”; (3) U.S. application Ser. No. 11/203,407, filed on Aug. 15, 2005, entitled “Method Of Patterning Ultra-Small Structures”; (4) U.S. application Ser. No. 11/243,476, filed on Oct. 5, 2005, entitled “Structures And Methods For Coupling Energy From An Electromagnetic Wave”; (5) U.S. application Ser. No. 11/243,477, filed on Oct. 5, 2005, entitled “Electron beam induced resonance”; (6) U.S. application Ser. No. 11/325,448, entitled “Selectable Frequency Light Emitter from Single Metal Layer,” filed Jan. 5, 2006; (7) U.S. application Ser. No. 11/325,432, entitled, “Matrix Array Display,” filed Jan. 5, 2006; (8) U.S. application Ser. No. 11/410,924, entitled, “Selectable Frequency EMR Emitter,” filed Apr. 26, 2006; and (9) U.S. application Ser. No. 11/349,963, filed Feb. 9, 2006, entitled “Method And Structure For Coupling Two Microcircuits,”.

A portion of the disclosure of this patent document contains material which is subject to copyright or mask work protection. The copyright or mask work owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright or mask work rights whatsoever.

This relates to electromagnetic radiation devices, and, more particularly, to coupling output from light-emitting structures.

Various light-emitting resonator structures have been disclosed, e.g., in the related applications listed above. For example, U.S. application Ser. No. 11/410,924, entitled, “Selectable Frequency EMR Emitter,” filed Apr. 26, 2006, which has been fully incorporated herein by reference, describes various optical transmitters including, in some embodiments, an optical switch using plural resonant structures emitting electromagnetic radiation resonant (EMR), where the resonant structures are excited by a charged particle source such as an electron beam.

It is desirable to couple such produced EMR into a waveguide, thereby allowing the light to be directed along a specific path.

The following description, given with respect to the attached drawings, may be better understood with reference to the non-limiting examples of the drawings, wherein:

FIGS. 1-3 show structures for coupling emitted light, according to embodiments of the present invention.

Various exemplary EMR-emitting micro-resonant structures have been described in the related applications. For example, U.S. application Ser. No. 11/410,924, (described more fully above, and incorporated herein by reference) entitled, “Selectable Frequency EMR Emitter,” describes various exemplary light-emitting micro-resonant structures. The structures disclosed therein can emit light (such as infrared light, visible light or ultraviolet light or any other electromagnetic radiation (EMR) at a wide range of possible frequencies, and often at a frequency higher than that of microwave). The EMR is emitted when the resonant structure is exposed to a beam of charged particles ejected from or emitted by a source of charged particles. The source may be controlled by applying a signal on a data input. The charged particle beam can include ions (positive or negative), electrons, protons and the like. The beam may be produced by any source, including, e.g., without limitation an ion gun, a thermionic filament, a tungsten filament, a cathode, a field-emission cathode, a planar vacuum triode, an electron-impact ionizer, a laser ionizer, a chemical ionizer, a thermal ionizer, an ion-impact ionizer and the like.

It is sometimes desirable to couple the emitted light so as to direct it to some other location. For example, a communications medium (e.g., a fiber optic cable) may be provided in close proximity to the resonant structures such that light emitted from the resonant structures is directed in the direction of a receiver, as is illustrated, e.g., in FIG. 21 of U.S. application Ser. No. 11/410,924.

FIG. 1 shows a typical light-emitting device 200 according to embodiments of the present invention. The device 200 includes at least one element 202 formed on a substrate 204 (such as a semiconductor substrate or a circuit board). The element 202 is made up of at least one resonant structure that emits light (such as infrared light, visible light or ultraviolet light or any other electromagnetic radiation (EMR) 206 at a wide range of possible frequencies, and often at a frequency higher than that of microwave). The EMR 206 is emitted when the resonant structure is exposed to a beam 208 of charged particles ejected from or emitted by a source of charged particles 210 . The charged particle beam can include ions (positive or negative), electrons, protons and the like. The beam may be produced by any source, including, e.g., without limitation an ion gun, a tungsten filament, a cathode, a planar vacuum triode, an electron-impact ionizer, a laser ionizer, a chemical ionizer, a thermal ionizer, an ion-impact ionizer.

The devices described produce electromagnetic radiation by the excitation of ultra-small resonant structures. The resonant excitation in the device described is induced by electromagnetic interaction which is caused, e.g., by the passing of a charged particle beam in close proximity to the device.

Such a device as represented in FIG. 1 may be made, e.g., using techniques such as described in U.S. patent application Ser. No. 10/917,511, entitled “Patterning Thin Metal Film by Dry Reactive Ion Etching” and/or U.S. application Ser. No. 11/203,407, entitled “Method Of Patterning Ultra-Small Structures,” both of which have been incorporated herein by reference. The element 202 may comprise any number of resonant microstructures constructed and adapted to produce EMR, e.g., as described above and/or in U.S. application Ser. No. 11/325,448, entitled “Selectable Frequency Light Emitter from Single Metal Layer,” filed Jan. 5, 2006, U.S. application Ser. No. 11/325,432, entitled, “Matrix Array Display,” filed Jan. 5, 2006, and U.S. application Ser. No. 11/243,476, filed on Oct. 5, 2005, entitled “Structures And Methods For Coupling Energy From An Electromagnetic Wave”; U.S. application Ser. No. 11/243,477, filed on Oct. 5, 2005, entitled “Electron beam induced resonance;” and U.S. application Ser. No. 11/302,471, entitled “Coupled Nano-Resonating Energy Emitting Structures,” filed Dec. 14, 2005.

The electromagnetic radiation produced by the nano-resonating structure 202 may be coupled to an electro-magnetic wave via a waveguide conduit 212 positioned in the proximity of nano-resonating structure 202 . The waveguide conduit may be, for example, an optical fiber or the like.

The actual positioning of a particular waveguide conduit will depend, at least in part, on the form and type particular nano-resonating structure 202 . Different structures will emit light at different angles relative to the surface of the substrate 204 , and relative to the various components of the structure 202 . In general, as shown, e.g., in FIG. 2 , light is emitted in a conical volume 214 , and the waveguide conduit 212 should be positioned within that volume, preferably centered within that volume.

In some cases it may be difficult to position the waveguide conduit 212 in an optimal or even suitable location. For example, depending on the structure 202 , the angle of the emitted light relative to the surface of the substrate 204 and/or the angle of the conical region may make positioning of the waveguide conduit difficult or even impossible. In such cases, additional reflective structure be provided, e.g., on the substrate, in order to direct the emitted light to the waveguide. In addition to reflecting the emitted light, the reflective structure may be used to narrow or widen the beam. For example, as shown in FIG. 3 , a reflective structure 216 is positioned on the surface of the substrate 204 to redirect the emitted light E (as light Er) to the waveguide conduit. Note that the conical volume 218 may have a wider or narrower angle than that of the light emitted from the structure 202 . Reflective structure 216 may comprise on or more reflective elements formed on the substrate 204 and/or in a package containing the substrate.

Those skilled in the art will immediately understand that more than one reflective structure 216 may be provided. Further, more than one nano-resonant structure 202 may emit light into the same reflective structure. In this manner, a single waveguide conduit may be provided for multiple nano-resonant structures.

It is preferable to position the waveguide conduit 212 to capture as much of the emitted light as possible.

In some embodiments of the present invention, the nano-resonating structure 202 and the waveguide conduit 212 may be integrated into a single microchip.

As used throughout this and the related applications, the word “light” (unless otherwise specifically limited) refers generally to any electromagnetic radiation (EMR) at a wide range of possible frequencies, regardless of whether it is visible to the human eye, including, e.g., infrared light, visible light or ultraviolet light.

While certain configurations of structures have been illustrated for the purposes of presenting the basic structures of the present invention, one of ordinary skill in the art will appreciate that other variations are possible which would still fall within the scope of the appended claims. While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.