Camera optical lens

The present disclosure relates to the field of optical lens, particular, to a camera optical lens suitable for handheld devices, such as smart phones and digital cameras, and imaging devices, such as monitors or PC lenses.

With the emergence of smart phones in recent years, the demand for miniature camera lens is increasing day by day, but in general the photosensitive devices of camera lens are nothing more than Charge Coupled Device (CCD) or Complementary Metal-Oxide Semiconductor Sensor (CMOS sensor), and as the progress of the semiconductor manufacturing technology makes the pixel size of the photosensitive devices become smaller, plus the current development trend of electronic products towards better functions and thinner and smaller dimensions, miniature camera lens with good imaging quality therefore have become a mainstream in the market. In order to obtain better imaging quality, the lens that is traditionally equipped in mobile phone cameras adopts a three-piece or four-piece lens structure. Also, with the development of technology and the increase of the diverse demands of users, and as the pixel area of photosensitive devices is becoming smaller and smaller and the requirement of the system on the imaging quality is improving constantly, the five-piece lens structure gradually appears in lens designs. There is an urgent need for an ultra-thin camera optical lens achieving excellent optical characteristics.

To illustrate the technical solutions according to the embodiments of the present disclosure or in the prior art more clearly, the accompanying drawings for describing the embodiments or the prior art are introduced briefly in the following. Apparently, the accompanying drawings in the following description are only some embodiments of the present disclosure, and persons of ordinary skill in the art can derive other drawings from the accompanying drawings without creative efforts.

FIG. 1 is a schematic diagram of a structure of a camera optical lens according to Embodiment 1 of the present disclosure.

FIG. 2 is a schematic diagram of a longitudinal aberration of the camera optical lens shown in FIG. 1 .

FIG. 3 is a schematic diagram of a lateral color of the camera optical lens shown in FIG. 1 .

FIG. 4 is a schematic diagram of a field curvature and a distortion of the camera optical lens shown in FIG 1 .

FIG. 5 is a schematic diagram of a structure of a camera optical lens according to Embodiment 2 of the present disclosure.

FIG. 6 is a schematic diagram of a longitudinal aberration of the camera optical lens shown in FIG. 5 .

FIG. 7 is a schematic diagram of a lateral color of the camera optical lens shown in FIG. 5 .

FIG. 8 is a schematic diagram of a field curvature and a distortion of the camera optical lens shown in FIG. 5 .

FIG. 9 is a schematic diagram of a structure of a camera optical lens according to Embodiment 3 of the present disclosure.

FIG. 10 is a schematic diagram of a longitudinal aberration of the camera. optical lens shown in FIG. 9 .

FIG. 11 is a schematic diagram of a lateral color of the camera optical lens shown in FIG. 9 .

FIG. 12 is a schematic diagram of a field curvature and a distortion of the camera optical lens shown in FIG. 9 .

The present disclosure will be further described with reference to the accompanying drawings and embodiments in the following.

To make the objects, technical solutions, and advantages of the present disclosure clearer, embodiments of the present disclosure are described in detail with reference to accompanying drawings in the following. A person of ordinary skill in the art can understand that, in the embodiments of the present disclosure, many technical details are provided to make readers better understand the present disclosure. However, even without these technical details and any changes and modifications based on the following embodiments, technical solutions required to be protected by the present disclosure can be implemented.

Referring to FIGS. 1-4 , the present disclosure provides a camera optical lens 10 of Embodiment 1 of the present disclosure. In FIG. 1 , the left side is an object side and the right side is an image side. The camera optical lens 10 includes five lenses, and specifically includes, from the object side to the image side: an aperture S 1 , a first lens L 1 , a second lens L 2 , a third lens L 3 , a fourth lens L 4 and a fifth lens L 5 . A glass plate GF is provided between the fifth lens L 5 and an image surface Si. The glass plate GF may be a glass cover plate or an optical filter.

In an embodiment, the first lens L 1 has a positive refractive power; the second lens L 2 has a negative refractive power; the third lens L 3 has a positive refractive power; the fourth lens L 4 has a positive refractive power; the fifth lens L 5 has a negative refractive power.

Here, a curvature radius of the object-side surface of the third lens L 3 is defined as R5, a curvature radius of the image-side surface of the third lens L 3 is defined as R6, a focal length of the entire camera optical lens 10 is defined as f, a focal length of the first lens L 1 is defined as f1, an on-axis thickness of the second lens L 2 is defines as d3, an on-axis distance from the image-side surface of the second lens L 2 to the object-side surface of the third lens L 3 is defined as d4, an on-axis thickness of the fourth lens L 4 is defined as d7, an on-axis distance from the image-side surface of the fourth lens L 4 to the object-side surface of the fifth lens L 5 is defined as d8, a curvature radius of the image-side surface of the second lens L 2 is defined as R4, and the camera optical lens 10 satisfies the following conditions:

0.50 ≤R 5 /R 6≤0.75   (1)

0.80 ≤f 1 /f≤ 1.00   (2)

0.80 ≤d 3 /d 4≤1.15   (3)

1.65 ≤d 7 /d 8≤2.50   (4)

0.00 ≤R 4   (5)

The condition (1) specifies a shape of the third lens L 3 . Within this range, the aberration can be effectively reduced, and the imaging quality can be improved.

The condition (2) specifies a range of a ratio of the focal length of the first lens to the focal length of the entire camera optical lens. Within this range, the imaging quality can be improved.

The condition (3) specifies a range of d3/d4, within which ultra-thin lenses can be achieved.

The condition (4) specifies a range of d7/d8, within which processing and assembly of the lenses can be facilitated.

The conditional expression (5) specifies that the curvature radius of the image-side surface of the second lens L 2 is greater than or equal to 0. Within the range, the aberration correction can be facilitated.

A curvature radius of the object-side surface of the fifth lens L 5 is defined as R9, a curvature radius of the image-side surface of the fifth lens L 5 is defined as R10, and the camera optical lens 10 further satisfies a condition of 2.00≤R9/R10≤5.00, which specifies a shape of the fifth lens L 5 . Within this range, the field curvature correction can be facilitated, and the imaging quality can be improved.

In an embodiment, the object-side surface of the first lens L 1 is convex in a paraxial region, and the image-side surface of the first lens L 1 is concave in the paraxial region.

A curvature radius of an object-side surface of the first lens L 1 is defined as R1, a curvature radius of an image-side surface of the first lens L 1 is defined as R2, and the camera optical lens 10 further satisfies a condition of −3.29≤(R1+R2)/(R1−R2)≤−0.77. This can reasonably control a shape of the first lens L 1 in such a manner that the first lens L 1 can effectively correct a spherical aberration of the camera optical lens. Preferably, the camera optical lens 10 thither satisfies a condition of −2.06≤(R1+R2)/(R1−R2)≤−0.97.

An on-axis thickness of the first lens L 1 is defined as d1, a total optical length from the object side surface of the first lens L 1 to an image surface Si of the camera. optical lens along an optical axis is defined as TTL, and the camera optical lens 10 further satisfies a condition of 0.06≤d1/TTL≤0.24. This can facilitate achieving ultra-thin lenses. Preferably, the camera optical lens 10 further satisfies a condition of 0.10≤d1/TTL≤0.19.

In an embodiment, an object-side surface of the second lens L 2 is convex in the proximal region, and an image-side surface of the second lens L 2 is concave in the proximal region.

A focal length of the second lens L 2 is defined as f2. The camera optical lens 10 further satisfies a condition of −9.10≤f2/f≤−1.09. By controlling a negative power of the second lens L 2 within a reasonable range, correction of the aberration of the optical system can be facilitated. Preferably, the camera optical lens 10 further satisfies a condition of −5.69≤f2/f≤−1.37.

A curvature radius of the object-side surface of the second lens L 2 . is defined as R3, a curvature radius of the image-side surface of the second lens L 2 is defined as R4, and the camera optical lens 10 further satisfies a condition of −2.00≤(R3+R4)/(R3−R4)≤1.62, which specifies a shape of the second lens L 2 . Within this range, a development towards ultra-thin and wide-angle lenses would facilitate correcting the problem of an axis aberration. Preferably, the camera optical lens 10 further satisfies a condition of −1.25≤(R3+R4)/(R3−R4)≤1.29.

An on-axis thickness of the second lens L 2 is defines as d3, and the camera optical lens 10 further satisfies a condition of 0.03≤d3/TTL≤0.09. This can facilitate achieving ultra-thin lenses. Preferably, the camera optical lens 10 further satisfies a condition of 0.05≤d3/TTL≤0.07.

In an embodiment, an object-side surface of the third lens L 3 is convex in the proximal region, and an image-side surface of the third lens L 3 is concave in the proximal region.

A focal length of the third lens L 3 is defined as f3, and the camera optical lens 10 further satisfies a condition of −192.44≤f3/f≤13.80. An appropriate distribution of the negative power leads to a better imaging quality and a lower sensitivity. Preferably, the camera optical lens 10 further satisfies a condition of −120.28≤f3/f≤11.04.

A curvature radius of the object-side surface of the third lens L 3 is defined as R5, a curvature radius of the image-side surface of the third lens L 3 is defined as R6,and the camera optical lens 10 further satisfies a condition of −13.44≤(R5+R6)/(R5−R6)−2.01. This can effectively control a shape of the third lens L 3 , thereby facilitating shaping of the third lens. Within this range, a deflection degree of the light passing through the lens can be alleviated to effectively reduce the aberration. Preferably, the camera optical lens 10 further satisfies a condition of −8.40≤(R5+R6)/(R5−R6)≤−2.51.

An on-axis thickness of the third lens L 3 is defined as d5, and the camera. optical lens 10 further satisfies a condition of 0.04≤d5/TTL≤0.17. This can facilitate achieving ultra-thin lenses. Preferably, the camera optical lens 10 further satisfies a condition of 0.06≤d5/TTL≤0.13.

In an embodiment, an object-side surface of the fourth lens L 4 is concave in the proximal region, and an image-side surface of the fourth lens L 4 is convex in the proximal region.

A focal length of the fourth lens L 4 is defined as f4, and the camera optical lens 10 further satisfies a condition of 0.44≤f4/f≤1.66. The appropriate distribution of positive refractive power makes it possible that the system has the better imaging quality and the lower sensitivity. Preferably, the camera optical lens 10 further satisfies a condition of 0.71≤f4/f≤1.33.

A curvature radius of the object-side surface of the fourth lens L 4 is defined as R7, a curvature radius of the image-side surface of the fourth lens L 4 is defined as R8, and the camera optical lens 10 further satisfies a condition of 0.27≤(R7+R8)/(R7−R8)≤2.53, which specifies a shape of the fourth lens L 4 . Within this range, a development towards ultra-thin and wide-angle lens would facilitate correcting a problem like an off-axis aberration. Preferably, the camera optical lens 10 further satisfies a condition of 0.43≤(R7+R8)/(R7−R8)≤2.02.

An on-axis thickness of the fourth lens L 4 is defined as d7, and the camera optical lens 10 further satisfies a condition of 0.07≤d7/1TTL≤0.25. This can facilitate achieving ultra-thin lenses. Preferably, the camera optical lens 10 further satisfies a condition of 0.11≤d7/TTL≤0.20.

In an embodiment, an object-side surface of the fifth lens L 5 is convex in the proximal region, and an image-side surface of the fifth lens L 5 is concave in the proximal region.

A focal length of the fifth lens L 5 is defined as f5, and the camera optical lens 10 further satisfies a condition of −1.65≤f≤−0.44, which can effectively make a light angle of the camera lens gentle and reduce a tolerance sensitivity. Preferably, the camera optical lens 10 further satisfies a condition of −1.03≤f5/f≤−0.55.

A curvature radius of the object-side surface of the fifth lens L 5 is defined as R9, a curvature radius of the image-side surface of the fifth lens L 5 is defined as R10, and the camera optical lens 10 further satisfies a condition of 0.75≤(R9+R10)/(R9−R10)≤4.22, which specifies a shape of the fifth lens L 5 . Within this range, a development towards ultra-thin and wide-angle lens would facilitate correcting a problem like an off-axis aberration. Preferably, the camera optical lens 10 further satisfies a condition of 1.21≤(R9+R10)/(R9−R10)≤3.38.

An on-axis thickness of the fifth lens L 5 is defined as d9, and the camera optical lens 10 further satisfies a condition of 0.04≤d9/TTL≤0.13. This can facilitate achieving ultra-thin lenses. Preferably, the camera optical lens 10 further satisfies a condition of 0.06≤d9/TTL≤0.10.

In an embodiment, an image height of the entire camera optical lens 10 is defined as IH, and the camera optical lens 10 further satisfies a condition of TTL/IH≤1.52, so as to achieve ultra-thin lenses.

In an embodiment, a field of view of the camera optical lens is defined as FOV, and the camera optical lens 10 further satisfies a condition of FOV≥77.00°, so as to achieve wide-angle lenses.

In an embodiment, an F number Fno of the camera optical lens 10 is less than or equal to 2.05, such that the camera optical lens 10 has a large aperture and a better imaging performance.

In an embodiment, a combined focal length of the first lens L 1 and the second lens L 2 is defined as f12, and the camera optical lens 10 further satisfies a condition of 0.47≤f12/f≤2.25. Within this range, the aberration and distortion of the camera optical lens 10 can be eliminated, and a back focal length of the camera optical lens 10 can be suppressed to maintain the miniaturization of the image lens system. Preferably, the camera optical lens 10 further satisfies a condition of 0.75≤f12/f≤1.80.

In addition, in the camera optical lens 10 provided in an embodiment, the surface of each lens may be aspherical. The aspherical surface can be easily made into a shape other than a spherical surface, and more control variables can be obtained to reduce aberration and thus to reduce the number of lenses, so that the total length of the camera optical lens 10 can be effectively reduced. In an embodiment, both the object-side surface and the image-side surface of each lens are aspherical.

It should be appreciated that since the first lens L 1 , the second lens L 2 , the third lens L 3 , the fourth lens L 4 , and the fifth lens L 5 have the aforementioned structure and parameter relationships, the optical powers, intervals, and shapes of the respective lenses in the camera optical lens 10 can be reasonably distributed, and thus various types of aberrations are corrected.

In addition, inflexion points and/or arrest points can be arranged on at least one of the object-side surface and the image-side surface of each lens, so as to satisfy the demand for high quality imaging. The description below can be referred for specific implementations.

The design data of the camera optical lens 10 in Embodiment 1 of the present disclosure are shown as follows.

Table 1 shows the curvature radiuses of the object-side surfaces and the image-side surfaces, the on-axis thicknesses, the on-axis distances d between adjacent lenses, the refractive indexes nd and the abbe number vd of the first to fifth lenses (L 1 to L 5 ) constituting the camera optical lens 10 in Embodiment 1 of the present disclosure. It should be noted that the focal length, on-axis distance, curvature radius, on-axis thickness, inflexion point position, and arrest point position are all in units of mm.

TTL: Optical length (the total optical length from the object side surface of the first lens to the image surface of the camera optical lens along the optical axis) in mm.

In the table, meanings of various symbols will be described as follows.

S 1 : aperture;

R: curvature radius of an optical surface, a central curvature radius for a lens;

R1: curvature radius of the object-side surface of the first lens L 1 ;

R2: curvature radius of the image-side surface of the first lens L 1 ;

R3: curvature radius of the object-side surface of the second lens L 2 ;

R4: curvature radius of the image-side surface of the second lens L 2 ;

R5: curvature radius of the object-side surface of the third lens L 3 ;

R6: curvature radius of the image-side surface of the third lens L 3 ;

R7: curvature radius of the object-side surface of the fourth lens L 4 ;

R8: curvature radius of the image-side surface of the fourth lens L 4 ;

R9: curvature radius of the object-side surface of the fifth lens L 5 ;

R10: curvature radius of the image-side surface of the fifth lens L 5 ;

R11: curvature radius of an object-side surface of the optical filter GF;

R12: curvature radius of an image-side surface of the optical filter GF;

d: on-axis thickness of a lens and an on-axis distance between lens;

d0: on-axis distance from the aperture S 1 to the object-side surface of the first lens L 1 ;

d1: on-axis thickness of the first lens L 1 ;

d2: on-axis distance from the image-side surface of the first lens L 1 to the object-side surface of the second lens L 2 ;

d3: on-axis thickness of the second lens L 2 ;

d4: on-axis distance from the image-side surface of the second lens L 2 to the object-side surface of the third lens L 3 ;

d5: on-axis thickness of the third lens L 3 ;

d6: on-axis distance from the image-side surface of the third lens L 3 to the object-side surface of the fourth lens L 4 ;

d7: on-axis thickness of the fourth lens L 4 ;

d8: on-axis distance from the image-side surface of the fourth lens L 4 to the object-side surface of the fifth lens L 5 ;

d9: on-axis thickness of the fifth lens L 5 ;

d10: on-axis distance from the image-side surface of the fifth lens L 5 to the object-side surface of the optical filter GF;

d11: on-axis thickness of the optical filter GF;

d12: on-axis distance from the image-side surface to the image surface of the optical filter GF;

nd: refractive index of the d line;

nd1: refractive index of the d line of the first lens L 1 ;

nd2: refractive index of the d line of the second lens L 2 ;

nd3: refractive index of the d line of the third lens L 3 ;

nd4: refractive index of the d line of the fourth lens L 4 ;

nd5: refractive index of the d line of the fifth lens L 5 ;

ndg: refractive index of the d line of the optical filter GF;

vd: abbe number;

v1: abbe number of the first lens L 1 ;

v2: abbe number of the second lens L 2 ;

v3: abbe number of the third lens L 3 ;

v4: abbe number of the fourth lens L 4 ;

v5: abbe number of the fifth lens L 5 ;

vg: abbe number of the optical filter GF.

Table 2 shows aspherical surface data of the camera optical lens 10 in Embodiment 1 of the present disclosure.

In table 2, K is a conic coefficient, and A4, A6, A8, A10, A12, A14, A16, A18 and A20 are aspheric surface coefficients.

IH: Image height

y =( x 2 /R )/[1+{1−( k+ 1)( x 2 /R 2 )} 1/2 ]+ A 4 x 4 +A 6 x 6 +A 8 x 8 +A 10 x 10 +A 12 x 12 +A 14 x 14 +A 16 x 16 +A 18 x 18 +A 20 x 20   (1)

For convenience, an aspheric surface of each lens surface uses the aspheric surfaces shown in the above formula (1). However, the present disclosure is not limited to the aspherical polynomials form shown in the formula (1).

Table 3 and Table 4 show design data of inflexion points and arrest points of each lens of the camera optical lens 10 according to the present embodiment. P1R1 and P1R2 represent the object-side surface and the image-side surface of the first lens L 1 , P2R1 and P2R2 represent the object-side surface and the image-side surface of the second lens L 2 , P3R1 and P3R2 represent the object-side surface and the image-side surface of the third lens L 3 , P4R1 and P4R2 represent the object-side surface and the image-side surface of the fourth lens L 4 , P5R1 and P5R2 represent the object-side surface and the image-side surface of the fifth lens L 5 . The data in the column named “inflexion point position” refer to vertical distances from inflexion points arranged on each lens surface to the optic axis of the camera optical lens 10 . The data in the column named “arrest point position” refer to vertical distances from arrest points arranged on each lens surface to the optical axis of the camera optical lens 10 .

In addition, in the subsequent Table 13, various parameters of Embodiments 1 and values corresponding to the parameters specified in the above conditions are shown.

FIG. 2 and FIG. 3 illustrate a longitudinal aberration and a lateral color with wavelengths of 486 nm, 546 nm, 435 nm, 587 nm and 656 nm after passing the camera optical lens 10 , respectively. FIG. 4 illustrates a field curvature and a distortion with a wavelength of 546 nm after passing the camera optical lens 10 . A field curvature S in FIG. 4 is a field curvature in a sagittal direction, and T is a field curvature in a tangential direction.

In this Embodiment, an entrance pupil diameter of the camera optical lens 10 is 1.504 mm, an image height of 1.0H is 2.59 mm, and an FOV (field of view) in a diagonal direction is 78.90°. Thus, the camera optical lens 10 has a large aperture, and is wide-angle and ultra-thin, thereby achieving excellent optical characteristics.

FIG. 5 is a schematic diagram of a structure of a camera optical lens 20 according to Embodiment 2. Embodiment 2 is basically the same as Embodiment 1 and involves symbols having the same meanings as Embodiment 1, and only differences therebetween will be described in the following,

An object-side surface of the second lens L 2 is concave in the proximal region, an object-side surface of the third lens L 3 is concave in the proximal region, and an image-side surface of the third lens L 3 is convex in the proximal region.

Table 5 and Table 6 show design data of a camera optical lens 20 in Embodiment 2 of the present disclosure.

Table 6 shows aspherical surface data of each lens of the camera optical lens 20 in Embodiment 2 of the present disclosure.

Table 7 and table 8 show design data of inflexion points and arrest points of each lens of the camera optical lens 20 .

In addition, in the subsequent Table 13, various parameters of Embodiments 2 and values corresponding to the parameters specified in the above conditions are shown.

FIG. 6 and FIG. 7 illustrate a longitudinal aberration and a lateral color of light with wavelengths of 435 nm, 486 nm, 587 nm, 546 nm and 656 nm after passing the camera optical lens 20 . FIG. 8 illustrates a field curvature and a distortion of light with a wavelength of 546 nm after passing the camera optical lens 20 . A field curvature S in FIG. 8 is a field curvature in a sagittal direction, and T is a field curvature in a tangential direction.

In an embodiment, an entrance pupil diameter of the camera optical lens 20 is 1.532 mm, an image height of 1.0H is 2.59 mm, and an FOV (field of view) in the diagonal direction is 78.00°. Thus, the camera optical lens 20 has a large aperture, and is wide-angle and ultra-thin, thereby achieving excellent optical characteristics.

FIG. 9 is a schematic diagram of a structure of a camera optical lens 30 according to Embodiment 3. Embodiment 3 is basically the same as Embodiment 1 and involves symbols having the same meanings as Embodiment 1, and only differences therebetween will be described in the following.

An object-side surface of the second lens L 2 is concave in the proximal region, an object-side surface of the third lens L 3 is concave in the proximal region, an image-side surface of the third lens L 3 is convex in the proximal region, and an object-side surface of the forth lens L 4 is convex in the proximal region.

Table 9 and Table 10 show design data of a camera optical lens 30 in Embodiment 3 of the present disclosure.

Table 10 shows aspherical surface data of each lens of the camera optical lens 30 in Embodiment 3 of the present disclosure.

Table 11 and Table 12 show design data inflexion points and arrest points of each lens in the camera optical lens 30 .

In addition, in the subsequent Table 13, various parameters of Embodiments 3 and values corresponding to the parameters specified in the above conditions are shown.

FIG. 10 and FIG. 11 illustrate a longitudinal aberration and a lateral color of light with wavelengths of 435 nm, 486 nm, 587 nm, 546 nm and 656 nm after passing the camera optical lens 30 . FIG. 12 illustrates a field curvature and a distortion of light with a wavelength of 546 nm after passing the camera optical lens 30 . A field curvature S in FIG. 12 is a field curvature in a sagittal direction, and T is a field curvature in a tangential direction.

In an embodiment, an entrance pupil diameter of the camera optical lens 30 is 1.564 mm, an image height of 1.0H is 2.59 mm, and an FOV (field of view) in the diagonal direction is 77.00°. Thus, the camera optical lens 30 has a large aperture, and is wide-angle and ultra-thin, thereby achieving excellent optical characteristics.

Table 13 in the following shows values corresponding to the conditions and values of other relevant parameters according to the aforementioned conditions in the Embodiment 1, Embodiment 2 and Embodiment 3.

Although the disclosure is illustrated and described herein with reference to specific embodiments, the disclosure is not intended to be limited to the details shown. Rather, various modifications may he made in the details within the scope and range of equivalents of the claims and without departing from the disclosure.