TWI442128B - Compact imaging lens assembly - Google Patents

Description

Thin photographic lens group

The present invention relates to a photographic lens group, and more particularly to a miniaturized two-piece thin photographic lens group applied to an electronic product.

In recent years, with the increasing demand for thin photographic lenses, and with the advancement of semiconductor process technology, photographic lenses are currently using a Coupled Coupled Device (CCD) or a complementary oxidized metal semiconductor component (Complementary). Metal-Oxide Semiconductor Sensor (CMOS Sensor)'s photosensitive elements are miniaturized in size, and today's electronic products are trending with thin, light and short shapes. Therefore, optical systems with good image quality and thin form have become The current mainstream in the market.

The conventional thin-type imaging optics group considers the correction of the aberrations, and the three-piece lens structure is mainly used, and the most common one is the positive and negative positive-riplet type, such as U.S. Patent No. 7,145,736. However, when the lens size is continuously reduced and reduced, the imaging space of the system is also tightened, which makes the placement of the three lenses difficult, and in a limited space, the thickness of the lens needs to be reduced, which will cause plastic injection molding. The manufactured lens has poor material uniformity.

In order to effectively shorten the total length of the lens and take into account the yield of the lens, a camera lens with only two lenses is a feasible solution. In order to correct the aberration, a pre-aperture is generally used. For example, a thin-type imaging optical lens group composed of two lenses is provided in the U.S. Patent No. 7,436,604, but the second lens shape is a double concave lens for aberrations and images. The effect of the loose correction is not as significant as that of the crescent lens.

In view of this, there is an urgent need for a thin photographic lens group which is simple in process and can effectively shorten the total length of the lens and provide good image quality.

In order to effectively reduce the lens volume, correct system aberrations and astigmatism, and to obtain higher resolution, the present invention provides a thinned photographic lens group composed of two lenses, the gist of which is as follows: a thin photographic lens group, The object side to the image side sequentially include: a first lens having a positive refractive power, the object side surface is a convex surface, the image side surface is a concave surface, and the object side surface and the image side surface are at least one aspherical surface; a second lens having a refractive power, wherein the object side surface is a concave surface, the image side surface is a convex surface, and at least one side of the object side surface and the image side surface is aspherical; the lens having a refractive power in the thinned photographic lens group is two pieces. And the first lens has a dispersion coefficient of V1, the second lens has a dispersion coefficient of V2, the thinned photographic lens group has an overall focal length of f, and the second lens has a focal length of f2, and the object side surface of the second lens The radius of curvature is R3. In addition, the thinned photographic lens group is further provided with an aperture, the distance from the aperture to the imaging plane on the optical axis is SL, and the distance from the object side surface of the first lens to the imaging plane on the optical axis is TTL, The following relationship is: 15<|V1-V2|<48; -0.43<f/f2<0; -1.50<R3/f<-0.40; 0.9<SL/TTL<1.1; by the above mirror configuration It can effectively reduce the lens volume, correct system aberrations and astigmatism, and achieve higher resolution.

Wherein: when the first lens has a positive refractive power, it provides a partial refractive power required by the system to help shorten the overall length of the system.

When the second lens has a negative refractive power, the system aberration can be effectively corrected, which helps to improve the imaging quality.

When the object side surface of the first lens is convex and the image side surface is concave, it can contribute to correcting system astigmatism.

When the object side surface of the second lens is a concave surface and the image side surface is a convex surface, it is advantageous to correct the high order aberration of the system.

When 15<|V1-V2|<48, it is beneficial to correct the chromatic aberration of the system; preferably, it satisfies 23<|V1-V2|<45; optimally, it satisfies 30<|V1-V2|<42 .

When -0.43<f/f2<0, the refractive power of the second lens is suitable, and the system aberration can be effectively corrected; preferably, it satisfies -0.27<f/f2<0.

When -1.50 < R3 / f < -0.40, the effect of correcting the aberration of the second lens can be enhanced; preferably, -1.20 < R3 / f < - 0.50 is satisfied.

When 0.9 < SL / TTL < 1.1, it is advantageous for the thinned photographic lens group to achieve a good balance between telecentric and wide-angle characteristics.

In the thinned photographic lens group of the present invention, the curvature radii of the object side surface and the image side surface of the first lens are R1 and R2, respectively, and when the two satisfy the relationship of 0<R1/R2<0.8, the system can be effectively corrected. The spherical aberration; preferably, it satisfies 0.40 < R1/R2 < 0.60.

In the thinned photographic lens group of the present invention, the center thickness of the first lens is CT1, and the center thickness of the second lens is CT2. When the two satisfy the relationship of 0.25<CT1/CT2<0.95, the first and second The lens thickness is relatively suitable, which can reduce the difficulty in manufacturing and assembling the first and second lenses; preferably, it satisfies 0.40<CT1/CT2<0.76.

In the thinned photographic lens group of the present invention, the refractive index of the first lens is N1, and the refractive index of the second lens is N2. When the two satisfy the relationship of N2>N1, the refractive indices of the first and second lenses are relatively Suitably, it is advantageous to shorten the total length of the system and maintain good image quality; preferably, it satisfies 0.04 < N2-N1 < 0.18.

In the thinned photographic lens group of the present invention, the distance from the image side surface of the second lens to the imaging surface on the optical axis is Bf, and the center thickness of the second lens is CT2, when the two satisfy 0.4<Bf/CT2<2.0 In the relational manner, there is sufficient space between the second lens and the electronic photosensitive element to place other components; preferably, it satisfies 0.95<Bf/CT2<1.65.

In the thinned photographic lens group of the present invention, the distance from the object side surface of the first lens to the imaging surface on the optical axis is TTL, and an electronic photosensitive element is disposed on the imaging surface, and the effective photosensitive area of the electronic photosensitive element is diagonal. Half of the line length is ImgH. When the two meet the TTL/ImgH<1.95 relationship, it is advantageous to maintain the miniaturization of the thin photographic lens group for mounting on thin and portable electronic products.

The present invention has been described in connection with the preferred embodiments of the present invention in accordance with the accompanying drawings.

For a thinned photographic lens group according to a first embodiment of the present invention, please refer to FIGS. 1A and 1B. FIG. 1A is a schematic view showing the configuration of a thinned photographic lens group according to a first embodiment of the present invention, and FIG. 1B is a view of the present invention. In the first embodiment, the first embodiment includes a first lens 110 having a positive refractive power and a material of plastic. The object side surface 111 of the first lens 110 is convex. The image side surface 112 is a concave surface, and the object side surface 111 and the image side surface 112 of the first lens 110 are both aspherical.

A second lens 120 having a negative refractive power is made of plastic, the object side surface 121 of the second lens 120 is a concave surface, the image side surface 122 is a convex surface, and the object side surface 121 and the image side surface of the second lens 120 are 122 are set to aspherical.

An aperture 100 is disposed between the subject (not shown) and the first lens 110.

An infrared filter (IR-filter) 170 is disposed between the image side surface 122 of the second lens 120 and an imaging surface 190. The infrared filter 170 is made of glass and does not affect the thinned photographic lens. The focal length of the group.

The equation for the above aspheric curve is expressed as follows:

X(Y)=(Y ² /R)/(1+sqrt(1-(1+k)*(Y/R) ² ))+ ( Ai )*( Y ⁱ )

Where: X: the point on the aspheric surface from the optical axis Y, the relative height of the tangent to the apex on the aspherical optical axis; Y: the distance between the point on the aspheric curve and the optical axis; k: the tapered surface Coefficient; A i : the i-th order aspheric coefficient.

In the first embodiment, the overall focal length of the thinned photographic lens group is f, and the relational expression is f=1.84.

In the first embodiment, the overall aperture value (f-number) of the thinned photographic lens group is Fno, and the relational expression is Fno = 2.45.

In the first embodiment, half of the overall maximum viewing angle of the thinned photographic lens group is HFOV, and the relational expression is HFOV=33.0.

In the first embodiment, the first lens 110 has a dispersion coefficient of V1, and the second lens 120 has a dispersion coefficient of V2, and the relationship is: |V1-V2|=32.5.

In the first embodiment, the refractive index of the first lens 110 is N1, and the refractive index of the second lens 120 is N2, and the relationship is: N2-N1=0.09.

In the first embodiment, the center thickness of the first lens 110 is CT1, and the center thickness of the second lens 120 is CT2, and the relationship is: CT1/CT2=0.59.

In the first embodiment, the radius of curvature of the object side surface 111 and the image side surface 112 of the first lens 110 are R1 and R2, respectively, and the relationship is: R1/R2=0.57.

In the first embodiment, the overall focal length of the thinned photographic lens group is f, and the radius of curvature of the object side surface 121 of the second lens 120 is R3, and the relationship is: R3/f=-1.01.

In the first embodiment, the overall focal length of the thinned photographic lens group is f, and the focal length of the second lens 120 is f2, and the relational expression is f/f2=-0.004.

In the first embodiment, the distance from the image side surface 122 of the second lens 120 to the imaging surface 190 on the optical axis 150 is Bf, and the center thickness of the second lens 120 is CT2, and the relationship is: Bf/CT2= 1.21.

In the first embodiment, the distance from the aperture 100 to the imaging surface 190 on the optical axis 150 is SL, and the distance from the object side surface 111 of the first lens 110 to the imaging surface 190 on the optical axis 150 is TTL, and the relationship is Is: SL / TTL = 0.94.

In the first embodiment, the distance from the object side surface 111 of the first lens 110 to the imaging surface 190 on the optical axis 150 is TTL, and the thinned photographic lens group is further provided with an electronic photosensitive element (not shown). The imaging surface 190, the half of the diagonal length of the effective pixel area of the electronic photosensitive element is ImgH, and the relationship is: TTL/ImgH=1.71.

The detailed structural data of the first embodiment is as shown in Fig. 1C, and the aspherical data is as shown in Fig. 1D, in which the unit of curvature radius, thickness, and focal length is mm (mm).

For a thinned photographic lens group according to a second embodiment of the present invention, please refer to FIGS. 2A and 2B. FIG. 2A is a schematic view showing a configuration of a thinned photographic lens group according to a second embodiment of the present invention, and FIG. 2B is a view of the present invention. The second embodiment includes an aberration curve. The second embodiment includes a first lens 210 having a positive refractive power and a material of plastic. The object side surface 211 of the first lens 210 is convex. The image side surface 212 is a concave surface, and the object side surface 211 and the image side surface 212 of the first lens 210 are both aspherical.

a second lens 220 having a negative refractive power, the material of which is plastic, the second through The object side surface 221 of the mirror 220 is a concave surface, and the image side surface 222 is a convex surface. The object side surface 221 and the image side surface 222 of the second lens 220 are both aspherical.

An aperture 200 is disposed between the subject (not shown) and the first lens 210.

An infrared filter (IR-filter) 270 is disposed between the image side surface 222 of the second lens 220 and an imaging surface 290. The infrared filter 270 is made of glass and does not affect the thinned photographic lens. The focal length of the group.

The expression of the aspheric curve equation of the second embodiment is the same as that of the first embodiment.

In the second embodiment, the overall focal length of the thinned photographic lens group is f, and the relational expression is f=1.96.

In the second embodiment, the overall aperture value (f-number) of the thinned photographic lens group is Fno, and the relational expression is Fno = 2.85.

In the second embodiment, half of the overall maximum viewing angle of the thinned photographic lens group is HFOV, and the relational expression is HFOV=31.0.

In the second embodiment, the first lens 210 has a dispersion coefficient of V1, and the second lens 220 has a dispersion coefficient of V2, and the relationship is: |V1-V2|=32.1.

In the second embodiment, the refractive index of the first lens 210 is N1, and the refractive index of the second lens 220 is N2, and the relationship is: N2-N1=0.09.

In the second embodiment, the center thickness of the first lens 210 is CT1, and the center thickness of the second lens 220 is CT2, and the relationship is: CT1/CT2=0.51.

In the second embodiment, the object side surface 211 and the image side table of the first lens 210 The radius of curvature of the surface 212 is R1 and R2, respectively, and the relationship is: R1/R2=0.48

In the second embodiment, the overall focal length of the thinned photographic lens group is f, and the radius of curvature of the object side surface 221 of the second lens 220 is R3, and the relationship is: R3/f=-0.61.

In the second embodiment, the overall focal length of the thinned photographic lens group is f, and the focal length of the second lens 220 is f2, and the relational expression is f/f2=-0.272.

In the second embodiment, the distance from the image side surface 222 of the second lens 220 to the imaging surface 290 on the optical axis 250 is Bf, and the center thickness of the second lens 220 is CT2, and the relationship is: Bf/CT2= 1.11.

In the second embodiment, the distance from the aperture 200 to the imaging surface 290 on the optical axis 250 is SL, and the distance from the object side surface 211 of the first lens 210 to the imaging surface 290 on the optical axis 250 is TTL, and the relationship is Is: SL / TTL = 0.94.

In the second embodiment, the distance from the object side surface 211 of the first lens 210 to the imaging surface 290 on the optical axis 250 is TTL, and the thinned photographic lens group is further provided with an electronic photosensitive element (not shown). The imaging surface 290, the half of the diagonal length of the effective pixel area of the electronic photosensitive element is ImgH, and the relationship is: TTL/ImgH=1.75.

The detailed structural data of the second embodiment is as shown in Fig. 2C, and the aspherical data is as shown in Fig. 2D, in which the unit of curvature radius, thickness, and focal length is mm (mm).

For a thinned photographic lens group according to a third embodiment of the present invention, please refer to FIGS. 3A and 3B. FIG. 3A is a schematic view showing a configuration of a thinned photographic lens group according to a third embodiment of the present invention, and FIG. 3B is a view of the present invention. In the third embodiment, the third embodiment includes a first lens 310 having a positive refractive power and a material of plastic. The object side surface 311 of the first lens 310 is convex. The image side surface 312 is a concave surface, and the object side surface 311 and the image side surface 312 of the first lens 310 are both aspherical.

A second lens 320 having a negative refractive power is made of plastic, the object side surface 321 of the second lens 320 is a concave surface, the image side surface 322 is a convex surface, and the object side surface 321 and the image side surface of the second lens 320 are 322 are all set to aspherical.

An aperture 300 is disposed between the subject (not shown) and the first lens 310.

An infrared filter (IR-filter) 370 is disposed between the image side surface 322 of the second lens 320 and an imaging surface 390. The infrared filter 370 is made of glass and does not affect the thinned photographic lens. The focal length of the group.

The expression of the aspheric curve equation of the third embodiment is the same as that of the first embodiment.

In the third embodiment, the overall focal length of the thinned photographic lens group is f, and the relational expression is f=1.89.

In the third embodiment, the overall aperture value (f-number) of the thinned photographic lens group is Fno, and the relational expression is Fno=3.00.

In the third embodiment, half of the overall maximum viewing angle of the thinned photographic lens group is HFOV, and the relational expression is HFOV=31.9.

In the third embodiment, the first lens 310 has a dispersion coefficient of V1, and the second lens 320 has a dispersion coefficient of V2, and the relationship is: |V1-V2|=25.6.

In the third embodiment, the refractive index of the first lens 310 is N1, and the refractive index of the second lens 320 is N2, and the relationship is: N2-N1=0.05.

In the third embodiment, the center thickness of the first lens 310 is CT1, and the center thickness of the second lens 320 is CT2, and the relationship is: CT1/CT2=0.47.

In the third embodiment, the radius of curvature of the object side surface 311 and the image side surface 312 of the first lens 310 are R1 and R2, respectively, and the relationship is: R1/R2=0.48.

In the third embodiment, the overall focal length of the thinned photographic lens group is f, and the radius of curvature of the object side surface 321 of the second lens 320 is R3, and the relationship is: R3/f=-0.60.

In the third embodiment, the overall focal length of the thinned photographic lens group is f, and the focal length of the second lens 320 is f2, and the relational expression is f/f2=-0.110.

In the third embodiment, the distance from the image side surface 322 of the second lens 320 to the imaging surface 390 on the optical axis 350 is Bf, and the center thickness of the second lens 320 is CT2, and the relationship is: Bf/CT2= 1.05.

In the third embodiment, the distance from the aperture 300 to the imaging surface 390 on the optical axis 350 is SL, and the distance from the object side surface 311 of the first lens 310 to the imaging surface 390 on the optical axis 350 is TTL, and the relationship is Is: SL / TTL = 0.95.

In the third embodiment, the distance from the object side surface 311 of the first lens 310 to the imaging surface 390 on the optical axis 350 is TTL, and the thinned photographic lens group is further provided with an electronic photosensitive element (not shown). The imaging surface 390, the half of the diagonal length of the effective pixel area of the electronic photosensitive element is ImgH, and the relationship is: TTL/ImgH=1.75.

The detailed structural data of the third embodiment is as shown in Fig. 3C, and the aspherical data is as shown in Fig. 3D, in which the unit of curvature radius, thickness, and focal length is mm (mm).

For a thinned photographic lens group according to a fourth embodiment of the present invention, please refer to FIGS. 4A and 4B. FIG. 4A is a schematic view showing a configuration of a thinned photographic lens group according to a fourth embodiment of the present invention, and FIG. 4B is a view of the present invention. The fourth embodiment includes an aberration curve. The fourth embodiment includes a first lens 410 having a positive refractive power and a material of plastic. The object side surface 411 of the first lens 410 is convex. The image side surface 412 is a concave surface, and the object side surface 411 and the image side surface 412 of the first lens 410 are both aspherical.

A second lens 420 having a negative refractive power is made of plastic, the object side surface 421 of the second lens 420 is a concave surface, the image side surface 422 is a convex surface, and the object side surface 421 and the image side surface of the second lens 420 are 422 are all set to aspherical.

An aperture 400 is disposed between the subject (not shown) and the first lens 410.

An infrared filter (IR-filter) 470 is disposed between the image side surface 422 of the second lens 420 and an imaging surface 490. The infrared filter 470 is made of glass and does not affect the thinned photographic lens. The focal length of the group.

The expression of the aspheric curve equation of the fourth embodiment is the same as that of the first embodiment.

In the fourth embodiment, the overall focal length of the thinned photographic lens group is f, Its relationship is: f = 1.89.

In the fourth embodiment, the overall aperture value (f-number) of the thinned photographic lens group is Fno, and the relational expression is Fno=2.60.

In the fourth embodiment, half of the overall maximum viewing angle of the thinned photographic lens group is HFOV, and the relational expression is HFOV=31.9.

In the fourth embodiment, the first lens 410 has a dispersion coefficient of V1, and the second lens 420 has a dispersion coefficient of V2, and the relationship is: |V1-V2|=34.4.

In the fourth embodiment, the refractive index of the first lens 410 is N1, and the refractive index of the second lens 420 is N2, and the relationship is: N2-N1=0.12.

In the fourth embodiment, the center thickness of the first lens 410 is CT1, and the center thickness of the second lens 420 is CT2, and the relationship is: CT1/CT2=0.53.

In the fourth embodiment, the radius of curvature of the object side surface 411 and the image side surface 412 of the first lens 410 are R1 and R2, respectively, and the relationship is: R1/R2=0.45.

In the fourth embodiment, the overall focal length of the thinned photographic lens group is f, and the radius of curvature of the object side surface 421 of the second lens 420 is R3, and the relational expression is: R3/f=-0.59.

In the fourth embodiment, the overall focal length of the thinned photographic lens group is f, and the focal length of the second lens 420 is f2, and the relational expression is f/f2=-0.167.

In the fourth embodiment, the distance from the image side surface 422 of the second lens 420 to the imaging surface 490 on the optical axis 450 is Bf, and the center thickness of the second lens 420 is CT2, and the relationship is: Bf/CT2= 1.23.

In the fourth embodiment, the aperture 400 is on the optical axis 450 of the imaging surface 490. The distance is SL, and the distance from the object side surface 411 of the first lens 410 to the imaging surface 490 on the optical axis 450 is TTL, and the relation is: SL/TTL=0.94.

In the fourth embodiment, the distance from the object side surface 411 of the first lens 410 to the imaging surface 490 on the optical axis 450 is TTL, and the thinned photographic lens group is further provided with an electronic photosensitive element (not shown). The imaging surface 490, the half of the diagonal length of the effective pixel area of the electronic photosensitive element is ImgH, and the relationship is: TTL/ImgH=1.75.

The detailed structural data of the fourth embodiment is as shown in Fig. 4C, and the aspherical data is as shown in Fig. 4D, in which the unit of curvature radius, thickness, and focal length is mm (mm).

For a thinned photographic lens group according to a fifth embodiment of the present invention, please refer to FIGS. 5A and 5B. FIG. 5A is a schematic view showing a configuration of a thinned photographic lens group according to a fifth embodiment of the present invention, and FIG. 5B is a view of the present invention. In the fifth embodiment, the fifth embodiment includes: a first lens 510 having a positive refractive power, the material is plastic, and the object side surface 511 of the first lens 510 is convex, The image side surface 512 is a concave surface, and the object side surface 511 and the image side surface 512 of the first lens 510 are both aspherical.

A second lens 520 having a negative refractive power is made of plastic, the object side surface 521 of the second lens 520 is a concave surface, the image side surface 522 is a convex surface, and the object side surface 521 and the image side surface of the second lens 520 are 522 are all set to aspherical.

An aperture 500 is disposed between the first lens 510 and the second lens 520.

An infrared filter (IR-filter) 570 is disposed between the image side surface 522 of the second lens 520 and an imaging surface 590. The infrared filter 570 is made of glass and does not affect the thinned photographic lens. The focal length of the group.

The expression of the aspheric curve equation of the fifth embodiment is the same as that of the first embodiment.

In the fifth embodiment, the overall focal length of the thinned photographic lens group is f, and the relational expression is f = 2.98.

In the fifth embodiment, the overall aperture value (f-number) of the thinned photographic lens group is Fno, and the relational expression is Fno = 2.85.

In the fifth embodiment, half of the overall maximum viewing angle of the thinned photographic lens group is HFOV, and the relational expression is HFOV=26.1.

In the fifth embodiment, the first lens 510 has a dispersion coefficient of V1, and the second lens 520 has a dispersion coefficient of V2, and the relationship is: |V1-V2|=33.1.

In the fifth embodiment, the refractive index of the first lens 510 is N1, and the refractive index of the second lens 520 is N2, and the relationship is: N2-N1=0.09.

In the fifth embodiment, the center thickness of the first lens 510 is CT1, and the center thickness of the second lens 520 is CT2, and the relationship is: CT1/CT2=0.76.

In the fifth embodiment, the radius of curvature of the object side surface 511 and the image side surface 512 of the first lens 510 are R1 and R2, respectively, and the relationship is: R1/R2=0.44.

In the fifth embodiment, the overall focal length of the thinned photographic lens group is f, and the radius of curvature of the object side surface 521 of the second lens 520 is R3, and the relational expression is: R3/f=-0.65.

In the fifth embodiment, the overall focal length of the thinned photographic lens group is f, and the focal length of the second lens 520 is f2, and the relational expression is f/f2=-0.390.

In the fifth embodiment, the distance from the image side surface 522 of the second lens 520 to the imaging surface 590 on the optical axis 550 is Bf, and the center thickness of the second lens 520 is CT2, and the relationship is: Bf/CT2= 0.97.

In the fifth embodiment, the distance from the aperture 500 to the imaging surface 590 on the optical axis 550 is SL, and the distance from the object side surface 511 of the first lens 510 to the imaging surface 590 on the optical axis 550 is TTL, and the relationship is Is: SL / TTL = 0.75.

In the fifth embodiment, the distance from the object side surface 511 of the first lens 510 to the imaging surface 590 on the optical axis 550 is TTL, and the thinned photographic lens group is further provided with an electronic photosensitive element (not shown). The imaging surface 590, the half of the diagonal length of the effective pixel area of the electronic photosensitive element is ImgH, and the relationship is: TTL/ImgH=2.13.

The detailed structural data of the fifth embodiment is as shown in Fig. 5C, and the aspherical data is as shown in Fig. 5D, in which the unit of the radius of curvature, the thickness, and the focal length is mm (mm).

For a thinned photographic lens group according to a sixth embodiment of the present invention, please refer to FIGS. 6A and 6B. FIG. 6A is a schematic view showing a configuration of a thinned photographic lens group according to a sixth embodiment of the present invention, and FIG. 6B is a view of the present invention. In the sixth embodiment, the sixth embodiment includes: a first lens 610 having a positive refractive power, the material is plastic, and the object side surface 611 of the first lens 610 is convex, Image side surface 612 is concave, the first Both the object side surface 611 and the image side surface 612 of the lens 610 are aspherical.

A second lens 620 having a negative refractive power is made of plastic, the object side surface 621 of the second lens 620 is a concave surface, the image side surface 622 is a convex surface, and the object side surface 621 and the image side surface of the second lens 620 are 622 are all set to aspherical.

An aperture 600 is disposed between the first lens 610 and the second lens 620.

An infrared filter (IR-filter) 670 is disposed between the image side surface 622 of the second lens 620 and an imaging surface 690. The infrared filter 670 is made of glass and does not affect the thinned photographic lens. The focal length of the group.

The expression of the aspheric curve equation of the sixth embodiment is the same as that of the first embodiment.

In the sixth embodiment, the overall focal length of the thinned photographic lens group is f, and the relational expression is f = 2.97.

In the sixth embodiment, the overall aperture value (f-number) of the thinned photographic lens group is Fno, and the relational expression is Fno=3.00.

In the sixth embodiment, half of the overall maximum viewing angle of the thinned photographic lens group is HFOV, and the relational expression is HFOV=26.0.

In the sixth embodiment, the first lens 610 has a dispersion coefficient of V1, and the second lens 620 has a dispersion coefficient of V2, and the relationship is: |V1-V2|=35.1.

In the sixth embodiment, the refractive index of the first lens 610 is N1, and the refractive index of the second lens 620 is N2, and the relationship is: N2-N1=0.11.

In the sixth embodiment, the center thickness of the first lens 610 is CT1, which is The center thickness of the two lenses 620 is CT2, and the relationship is: CT1/CT2 = 0.75.

In the sixth embodiment, the radius of curvature of the object side surface 611 and the image side surface 612 of the first lens 610 are R1 and R2, respectively, and the relationship is: R1/R2=0.53.

In the sixth embodiment, the overall focal length of the thinned photographic lens group is f, and the radius of curvature of the object side surface 621 of the second lens 620 is R3, and the relationship is: R3/f=-0.69.

In the sixth embodiment, the overall focal length of the thinned photographic lens group is f, and the focal length of the second lens 620 is f2, and the relational expression is f/f2=-0.225.

In the sixth embodiment, the distance from the image side surface 622 of the second lens 620 to the imaging surface 690 on the optical axis 650 is Bf, and the center thickness of the second lens 620 is CT2, and the relationship is: Bf/CT2= 0.96.

In the sixth embodiment, the distance from the aperture 600 to the imaging surface 690 on the optical axis 650 is SL, and the distance from the object side surface 611 of the first lens 610 to the imaging surface 690 on the optical axis 650 is TTL, and the relationship is Is: SL / TTL = 0.74.

In the sixth embodiment, the distance from the object side surface 611 of the first lens 610 to the imaging surface 690 on the optical axis 650 is TTL, and the thinned photographic lens group is further provided with an electronic photosensitive element (not shown). The imaging surface 690, the half of the diagonal length of the effective pixel area of the electronic photosensitive element is ImgH, and the relationship is: TTL/ImgH=2.16.

The detailed structural data of the sixth embodiment is as shown in Fig. 6C, and the aspherical data is as shown in Fig. 6D, in which the unit of the radius of curvature, the thickness, and the focal length are in millimeters (mmm).

It should be noted that the first C, 1D, 2C, 2D, 3C, 3D, 4C, 4D, 5C, 5D, 6C, and 6D drawings show different numerical value change tables of the embodiments of the thinned photographic lens group of the present invention. However, the numerical changes of the various embodiments of the present invention are experimentally obtained, and even if different values are used, the products of the same structure are still within the protection scope of the present invention. Fig. 7 is a correspondence table of the respective relational expressions in the respective embodiments.

In the thin photographic lens group of the present invention, the material of each lens may be glass or plastic. If the material of each lens is glass, the degree of freedom of the refractive power of the thin photographic lens group may be increased, and if each lens material is plastic, It can effectively reduce production costs. In addition, an aspherical surface can be provided on the mirror surface, and the aspherical surface can be easily formed into a shape other than the spherical surface, and more control variables are obtained to reduce the aberration and thereby reduce the number of lenses used, thereby effectively reducing the thinning photography of the present invention. The total length of the lens group.

In the thinned photographic lens group of the present invention, if the surface of the lens is convex, the surface of the lens is convex at the paraxial axis; and if the surface of the lens is concave, it indicates that the surface of the lens is concave at the paraxial axis.

In the thinned photographic lens group of the present invention, at least one light barrier can be provided to reduce stray light, which contributes to image quality improvement.

110, 210, 310, 410, 510, 610‧‧‧ first lens

111, 211, 311, 411, 511, 611‧‧‧ ‧ side surface

112, 212, 312, 412, 512, 612‧‧‧ side surface

120, 220, 320, 420, 520, 620‧‧‧ second lens

121, 221, 321, 421, 521, 621 ‧ ‧ ‧ side surface

122, 222, 322, 422, 522, 622‧‧‧ side surface

100, 200, 300, 400, 500, 600‧‧ ‧ aperture

150, 250, 350, 450, 550, 650 ‧ ‧ optical axis

170, 270, 370, 470, 570, 670‧‧‧ Infrared Filters (IR Filter)

190, 290, 390, 490, 590, 690‧‧ ‧ imaging surface

CT1‧‧‧ center thickness of the first lens

CT2‧‧‧ center thickness of the second lens

f‧‧‧The overall focal length of the optical photography system

F2‧‧‧The focal length of the second lens

ImgH‧‧‧Electronic photosensitive element is half the length of the diagonal of the effective pixel area

R1‧‧‧ radius of curvature of the object side surface of the first lens

R2‧‧‧ Image side surface radius of curvature of the first lens

R3‧‧‧ radius of curvature of the object side surface of the second lens

SL‧‧‧ aperture to the distance of the imaging surface on the optical axis

TTL‧‧‧The distance from the object side surface of the first lens to the imaging surface on the optical axis

V1‧‧‧Dispersion coefficient of the first lens

V2‧‧‧Dispersion coefficient of the second lens

N1‧‧‧Refractive index of the first lens

N2‧‧‧ refractive index of the second lens

Bf‧‧‧ The distance from the image side surface of the second lens to the imaging surface on the optical axis

Fig. 1A is an optical schematic view of a first embodiment of the present invention.

Fig. 1B is a diagram showing aberrations of the first embodiment of the present invention.

Fig. 1C Fig. First embodiment optical data.

Fig. 1D Fig. First embodiment aspherical data.

Fig. 2A is an optical schematic view of a second embodiment of the present invention.

Fig. 2B is a diagram showing aberrations of the second embodiment of the present invention.

Figure 2C Second embodiment optical data.

Figure 2D Second embodiment Aspherical data.

Fig. 3A is an optical schematic view of a third embodiment of the present invention.

Fig. 3B is a diagram showing aberrations of the third embodiment of the present invention.

Fig. 3C Fig. 3 embodiment optical data.

Figure 3D Figure 3 Aspherical data.

Fig. 4A is an optical schematic view showing a fourth embodiment of the present invention.

Fig. 4B is a diagram showing aberrations of the fourth embodiment of the present invention.

Figure 4C Figure 4 Optical data of the fourth embodiment.

Fig. 4D is a fourth embodiment of aspherical data.

Fig. 5A is an optical schematic view showing a fifth embodiment of the present invention.

Fig. 5B is a diagram showing aberrations of the fifth embodiment of the present invention.

Figure 5C Fifth embodiment optical data.

Figure 5D Figure 5 Aspherical data of the fifth embodiment.

Fig. 6A is an optical schematic view of a sixth embodiment of the present invention.

Fig. 6B is a diagram showing aberrations of the sixth embodiment of the present invention.

Figure 6C Figure 6 Optical data of the embodiment.

Fig. 6D is a sixth embodiment of aspherical data.

Figure 7 Numerical data of the correlation of the present invention.

110. . . First lens

111. . . Side surface

112. . . Image side surface

120. . . Second lens

121. . . Side surface

122. . . Image side surface

100. . . aperture

150. . . Optical axis

170. . . Infrared filter (IR Filter)

190. . . Imaging surface

Claims (22)

A thinned photographic lens group comprising, in order from the object side to the image side, a first lens having a positive refractive power, the object side surface being a convex surface, the image side surface being a concave surface, and the object side surface and the image side surface at least one side a non-spherical surface; a second lens having a negative refractive power, the object side surface is a concave surface, the image side surface is a convex surface, and the object side surface and the image side surface are at least one aspherical surface; the thinned photographic lens group has an inflection The lens of the force is two pieces, and the first lens has a dispersion coefficient of V1, the second lens has a dispersion coefficient of V2, the thinned photographic lens group has an overall focal length of f, and the second lens has a focal length of f2. The radius of curvature of the object side surface of the second lens is R3. Further, the thinned photographic lens group is further provided with an aperture, the distance from the aperture to the imaging plane on the optical axis is SL, and the object side surface of the first lens to the imaging surface The distance on the optical axis is TTL, which satisfies the following relationship: 15<|V1-V2|<48; -0.43<f/f2<0; -0.69≦R3/f<-0.40; 0.9<SL/TTL<1.1 . The thinned photographic lens unit of claim 1, wherein the first lens is made of plastic, and the object side surface and the image side surface are aspherical, and the second lens is made of plastic, and Both the object side surface and the image side surface are aspherical. A thinned photographic lens group as described in claim 2, wherein The radius of curvature of the object side surface and the image side surface of the first lens are R1 and R2, respectively, and both satisfy the following relationship: 0 < R1/R2 < 0.8. The thinned photographic lens group according to claim 3, wherein the first lens has a dispersion coefficient of V1 and the second lens has a dispersion coefficient of V2, and both satisfy the following relationship: 23<|V1-V2 |<45. The thinned photographic lens group according to claim 4, wherein the first lens has a dispersion coefficient of V1 and the second lens has a dispersion coefficient of V2, and both satisfy the following relationship: 30<|V1-V2 |<42. The thinned photographic lens group according to claim 3, wherein the thinned photographic lens group has an overall focal length of f and the second lens has a focal length of f2, and both satisfy the following relationship: -0.27<f/ F2<0. The thinned photographic lens group according to claim 3, wherein the thinned photographic lens group has an overall focal length of f, and the object side surface has a radius of curvature of R3, and the two satisfy the following relationship: 0.69 ≦ R3 / f < - 0.50. The thinned photographic lens group according to claim 3, wherein a center thickness of the first lens is CT1, and a center thickness of the second lens is CT2, and the two satisfy the following relationship: 0.25<CT1/CT2< 0.95. The thinned photographic lens group according to claim 8, wherein a center thickness of the first lens is CT1, and a center thickness of the second lens is CT2, and the two satisfy the following relationship: 0.40<CT1/CT2< 0.76. The thinned photographic lens group according to claim 3, wherein the first lens has a refractive index of N1 and the second lens has a refractive index of N2. The following relationship is: 0.04 < N2-N1 < 0.18. The thinned photographic lens assembly of claim 3, wherein a distance from an image side surface of the second lens to an imaging surface on an optical axis is Bf, and a center thickness of the second lens is CT2, both of which satisfy The following relationship: 0.95 < Bf / CT2 < 1.65. The thinned photographic lens group according to claim 3, wherein the radius of curvature of the object side surface and the image side surface of the first lens are R1 and R2, respectively, and the two satisfy the following relationship: 0.40<R1/R2 <0.60. The thinned photographic lens assembly of claim 3, wherein a distance from the object side surface of the first lens to the imaging surface on the optical axis is TTL, and an electronic photosensitive element is disposed on the imaging surface, the electron The half of the diagonal length of the effective pixel area of the photosensitive element is ImgH, and the two satisfy the following relationship: TTL/ImgH<1.95. A thinned photographic lens group comprising, in order from the object side to the image side, a first lens having a positive refractive power, wherein the object side surface is a convex surface, and the image side surface is a concave surface, and the object side surface and the image side surface are both In the aspherical surface, the first lens is a plastic; the second lens having a negative refractive power, the object side surface is a concave surface, the image side surface is a convex surface, and the object side surface and the image side surface are both aspherical, the second lens a plastic lens; the lens having a refractive power in the thinned photographic lens group is two, and the first lens has a dispersion coefficient of V1, the second lens has a dispersion coefficient of V2, and the overall focal length of the thinned photographic lens group is f, the focal length of the second lens is f2, the refractive index of the first lens is N1, the refractive index of the second lens is N2, and the distance from the image side surface of the second lens to the imaging surface on the optical axis is Bf, Center thickness of the second lens For CT2, the radius of curvature of the object side surface of the second lens is R3, which satisfies the following relationship: 15<|V1-V2|<48; -0.43<f/f2<0; N2>N1; 0.4<Bf/CT2< 2.0; -0.69≦R3/f<-0.40. The thinned photographic lens group according to claim 14, wherein the first lens has a refractive index of N1 and the second lens has a refractive index of N2, and both satisfy the following relationship: 0.04<N2-N1< 0.18. The thinned photographic lens group according to claim 14, wherein a distance from the image side surface of the second lens to the imaging surface on the optical axis is Bf, and a center thickness of the second lens is CT2, both of which satisfy The following relationship: 0.95 < Bf / CT2 < 1.65. The thinned photographic lens assembly of claim 16, wherein the thinned photographic lens group is further provided with an aperture, the distance from the aperture to the imaging surface on the optical axis is SL, and the object side surface of the first lens The distance to the imaging plane on the optical axis is TTL, which satisfies the following relationship: 0.9<SL/TTL<1.1. The thinned photographic lens group according to claim 17, wherein the first lens has a chromatic dispersion coefficient of V1 and the second lens has a chromatic dispersion coefficient of V2, and the two satisfy the following relationship: 30<|V1-V2 |<42. The thinned photographic lens group of claim 16, wherein the thinned photographic lens group has an overall focal length of f, and the focal length of the second lens is F2, both satisfy the following relationship: -0.27<f/f2<0. The thinned photographic lens group according to claim 16, wherein the thinned photographic lens group has an overall focal length of f, and the object side surface has a radius of curvature of R3, and the two satisfy the following relationship: 0.69 ≦ R3 / f < - 0.50. The thinned photographic lens group according to claim 16, wherein the first lens has a center thickness of CT1 and the second lens has a center thickness of CT2, and the two satisfy the following relationship: 0.40<CT1/CT2< 0.76. The thinned photographic lens group according to claim 16, wherein the radius of curvature of the object side surface and the image side surface of the first lens are R1 and R2, respectively, and the two satisfy the following relationship: 0.40<R1/R2 <0.60.