TW202020500A - Wide-angle imaging lens, imaging device and electronic device having the same - Google Patents

Abstract

A wide-angle imaging lens, an imaging device and an electronic device having the same are provided. The wide-angle imaging lens includes, from an object side to an image side, a first lens having negative refractive power, an aperture stop, a second lens having positive refractive power, a third lens having positive refractive power and a fourth lens having negative refractive power, wherein the first lens has an object-side surface being convex and an image-side surface being concave; the second lens has an object-side surface being convex; the third lens has an image-side surface being convex; the fourth lens has an object-side surface being concave and an image-side surface being convex. When the wide-angle imaging lens satisfies a specific condition, the refractive powers of the lenses could be balanced, a total track length thereof could be shortened, and the aberration of the imaging lens could be corrected, and thereby being capable of providing a wide-angle image having an improved image quality.

Description

Wide-angle imaging lens group, imaging device and electronic device

The invention relates to a wide-angle imaging device, in particular to a wide-angle imaging lens group that can be used in portable electronic devices, medical photography devices or vehicle photography devices, and an imaging device and an electronic device having the wide-angle imaging lens group Device.

With the advancement of semiconductor manufacturing technology, the size of the photosensitive elements (such as CCD and CMOS Image Sensor) required for photographic devices can be reduced and meet the requirements of miniaturized photographic devices, thus driving consumer electronics products to be equipped with miniaturized cameras ) To improve the development trend of product added value. Taking portable electronic devices such as mobile phones as an example, because of their convenient portability, today's consumers often replace the habit of using traditional digital cameras with mobile phones for taking pictures. However, consumers are increasingly demanding portable electronic devices. In addition to their beautiful appearance, they also pursue small size and light weight. Therefore, this trend makes it necessary to further miniaturize the overall size of the compact camera mounted on the portable electronic device before it can be accommodated in electronic products that are light, thin, and short.

In addition, due to the increasing demands of consumers on the photography function of portable electronic products, and the diversified development of the application scope of optical lenses, such as vehicle photography devices, image recognition systems, smart home assist systems, and AR/VR entertainment products, etc. The angle of view provided by traditional miniaturized photographic devices has gradually failed to meet the needs of consumers, and is developing towards a wider angle of view. However mention The high viewing angle of the photographic device will reduce the resolution of the imaging quality, and the wide viewing angle imaging device usually uses a lens with negative refractive power at the position of the first lens to increase the light receiving range. In order to correct the aberration caused by the wide-angle incident light, Additional lenses are needed to correct aberrations, and various factors will increase the total lens length of the wide-angle imaging device.

Therefore, how to provide a miniaturized wide-angle imaging device has become an urgent problem to be solved by those in the technical field.

The invention provides a wide-angle imaging lens group, which includes, in order from the object side to the image side, a first lens with negative refractive power, an aperture, a second lens with positive refractive power, and a first lens with positive refractive power Three lenses, and a fourth lens with negative refractive power. The first lens includes an object side and an image side, the object side of the first lens is convex, and the image side of the first lens is concave; the second lens includes an object side and an image side, and the second lens The object side is convex; the third lens includes an object side and an image side, and the image side of the third lens is convex; and, the fourth lens includes an object side and an image side, and the object side of the fourth lens is concave, The image side of the fourth lens is convex.

This wide-angle imaging lens group satisfies the following conditions: 0.5<|f1/f2|<1.2; and 0.1<|f/f4|<1.2.

Where, f is the effective focal length of the wide-angle imaging lens group, f1 is the focal length of the first lens, f2 is the focal length of the second lens, and f4 is the focal length of the fourth lens.

According to an embodiment of the present invention, wherein the thicknesses of the first lens to the fourth lens on the optical axis are CT1, CT2, CT3, and CT4, respectively, and the image side of the first lens and the second lens The distance of the object side on the optical axis is AT1, and the wide-angle imaging lens group satisfies the following conditions: 0.1<AT1/(CT1+CT2+CT3+CT4)<0.42.

According to an embodiment of the present invention, the radius of curvature of the object side and the image side of the first lens are R1 and R2, respectively, and the wide-angle imaging lens group satisfies the following conditions: 1<(R1+R2)/(R1-R2) <2.7.

According to an embodiment of the present invention, wherein the dispersion coefficient of the third lens is V3, the dispersion coefficient of the fourth lens is V4, and the wide-angle imaging lens group satisfies the following condition: 0.2<V4/V3<0.5.

According to an embodiment of the present invention, wherein one half of the maximum viewing angle of the wide-angle imaging lens group is HFOV, which satisfies the following condition: 45 degrees<HFOV<85 degrees.

According to an embodiment of the present invention, the image side of the second lens is convex.

According to an embodiment of the present invention, the image side of the second lens is concave away from the optical axis.

According to an embodiment of the present invention, the image side of the second lens is concave.

According to an embodiment of the present invention, the object side of the third lens is convex.

According to an embodiment of the present invention, the object sides and the image sides of the first lens to the fourth lens are all aspherical.

According to an embodiment of the present invention, wherein the wide-angle imaging lens group further satisfies the following condition: 0.1<|f/f4|<1.

The present invention further provides an imaging device including the wide-angle imaging transparent lens as described above Mirror group.

The present invention further provides an electronic device including the imaging device as described above.

10, 20, 30, 40, 50, 60 ‧‧‧ wide-angle imaging lens group

11, 21, 31, 41, 51, 61‧‧‧ First lens

12, 22, 32, 42, 52, 62 ‧‧‧ second lens

13, 23, 33, 43, 53, 63‧‧‧ third lens

14, 24, 34, 44, 54, 64 ‧‧‧ fourth lens

11a, 21a, 31a, 41a, 51a, 61a object side of the first lens

11b, 21b, 31b, 41b, 51b, 61b image side of the first lens

12a, 22a, 32a, 42a, 52a, 62a object side of the second lens

12b, 22b, 32b, 42b, 52b, 62b image side of the second lens

13a, 23a, 33a, 43a, 53a, 63a object side of the third lens

13b, 23b, 33b, 43b, 53b, 63b ‧‧‧ Image side of the third lens

14a, 24a, 34a, 44a, 54a, 64a object side of the fourth lens

14b, 24b, 34b, 44b, 54b, 64b image side of the fourth lens

15, 25, 35, 45, 55, 65 ‧‧‧ filter element

16, 26, 36, 46, 56, 66 ‧‧‧ imaging surface

I‧‧‧optic axis

ST‧‧‧ Aperture

100, 200, 300, 400, 500, 600

FIG. 1A is a schematic diagram of a wide-angle imaging lens group according to the first embodiment of the invention.

FIG. 1B is a longitudinal spherical aberration diagram of the first embodiment of the present invention.

FIG. 1C is a field curvature aberration diagram of the first embodiment of the present invention.

FIG. 1D is a distortion aberration diagram of the first embodiment of the present invention.

2A is a schematic diagram of a wide-angle imaging lens group according to a second embodiment of the invention.

2B is a longitudinal spherical aberration diagram of the second embodiment of the invention.

FIG. 2C is a field curvature aberration diagram of the second embodiment of the present invention.

2D is a distortion aberration diagram of the second embodiment of the present invention.

3A is a schematic diagram of a wide-angle imaging lens group according to a third embodiment of the invention.

3B is a longitudinal spherical aberration diagram of the third embodiment of the invention.

FIG. 3C is a field curvature aberration diagram of the third embodiment of the present invention.

FIG. 3D is a distortion aberration diagram of the third embodiment of the present invention.

4A is a schematic diagram of a wide-angle imaging lens group according to a fourth embodiment of the invention.

4B is a longitudinal spherical aberration diagram of the fourth embodiment of the present invention.

4C is a field curvature aberration diagram of the fourth embodiment of the present invention.

4D is a distortion aberration diagram of the fourth embodiment of the present invention.

5A is a schematic diagram of a wide-angle imaging lens group according to a fifth embodiment of the invention.

5B is a longitudinal spherical aberration diagram of the fifth embodiment of the present invention.

5C is a field curvature aberration diagram of the fifth embodiment of the present invention.

FIG. 5D is a distortion aberration diagram of the fifth embodiment of the present invention.

6A is a schematic diagram of a wide-angle imaging lens group according to a sixth embodiment of the invention.

6B is a longitudinal spherical aberration diagram of the sixth embodiment of the present invention.

6C is a field curvature aberration diagram of the sixth embodiment of the present invention.

6D is a distortion aberration diagram of the sixth embodiment of the present invention

The wide-angle imaging lens group of the present invention includes a first lens, an aperture, a second lens, a third lens, and a fourth lens in order from the object side to the image side.

In the embodiment of the present invention, each lens includes an object side facing the subject and an image side facing the imaging plane. Each object side and image side includes a surface area near the optical axis and a surface area away from the optical axis. In the following description, the shape of each lens surface is convex or concave. If it is not clearly specified to be near the axis or away from the optical axis, it means that the shape of the surface area at the near axis is convex or concave.

The first lens of the wide-angle imaging lens group of the present invention has negative refractive power, and its surface close to the object side (object side) is convex, and the surface close to the image side (image side) is concave. Thereby, the incident light in a larger angle range can be received, and the light collection range of the imaging lens group is improved.

The second lens has a positive refractive power, and its object side is convex. The third lens has a positive refractive power, and its image side is convex. Thereby, the negative refractive power of the first lens can be balanced. The aperture is disposed between the first lens and the second lens to reduce stray light. The focal length of the first lens is f1, and the focal length of the second lens is f2, and the following conditions are satisfied: 0.5<|f1/f2|<1.2. By properly configuring the focal lengths of the first lens and the second lens, it helps to reduce the overall total length of the wide-angle imaging lens group and improve Light collection effect.

The fourth lens has negative refractive power, its object side is concave, and its image side is convex. With the design that the first lens and the fourth lens have a negative refractive power, and the second lens and the third lens have a positive refractive power, it is possible to effectively expand the angle of view and correct the curvature of field. Among them, the effective focal length of the wide-angle imaging lens group is f, and the focal length of the fourth lens is f4, and the following conditions are satisfied: 0.1<|f/f4|<1.2. Preferably, the wide-angle imaging lens group satisfies the following condition: 0.1<|f/f4|<1. By appropriately configuring the ratio between the effective focal length of the wide-angle imaging lens group and the focal length of the fourth lens, it can help correct astigmatism.

The distance between the image side of the first lens and the object side of the second lens on the optical axis is AT1, and the thicknesses of the first lens to the fourth lens on the optical axis are CT1, CT2, CT3, and CT4, which can satisfy the following Condition: 0.1<AT1/(CT1+CT2+CT3+CT4)<0.42. Thereby, the curvature or outer diameter of the first lens can be prevented from being too large, and the distortion can be corrected effectively.

The radius of curvature of the object side of the first lens is R1, and the radius of curvature of its image side is R1, which can satisfy the following conditions: 1<(R1+R2)/(R1-R2)<2.7. In this way, the curvature or outer diameter of the first lens can be prevented from being too large, and the aberration can be corrected effectively.

The third lens has a dispersion coefficient of V3, and the fourth lens has a dispersion coefficient of V4, which can satisfy the following conditions: 0.2<V4/V3<0.5. With this, the chromatic aberration of the wide-angle imaging lens group can be effectively corrected.

Half of the maximum viewing angle of the wide-angle imaging lens group is HFOV (Half Field of View), which satisfies the following conditions: 45 degrees <HFOV<85 degrees.

<First embodiment>

FIG. 1A is a schematic diagram of a wide-angle imaging lens group according to the first embodiment of the invention. 1B is a longitudinal spherical aberration diagram (Longitudinal Spherical Aberration) of the wide-angle imaging lens group according to the first embodiment of the present invention. FIG. 1C is a field curve aberration diagram of the wide-angle imaging lens group according to the first embodiment of the present invention. FIG. 1D is a distortion aberration diagram of the wide-angle imaging lens group according to the first embodiment of the present invention.

As shown in FIG. 1A, the wide-angle imaging lens group 10 of the first embodiment includes a first lens 11, an aperture ST, a second lens 12, a third lens 13, and a fourth lens 14 in order from the object side to the image side. Filter element 15 and imaging surface 16. Wherein, the object side is a side close to the object to be photographed, and the image side is a side close to the imaging surface 16. The wide-angle imaging lens group 10 can further be equipped with an electronic photosensitive element 100 (provided on the imaging surface 16) to form a wide-angle imaging device (not otherwise labeled).

The first lens 11 has a negative refractive power, and its material is glass. The first lens 11 has an object side surface 11a facing the object side and an image side surface 11b facing the image side, wherein the object side surface 11a is convex and the image side surface 11b is concave, and both surfaces 11a and 11b are aspherical.

The second lens 12 has positive refractive power and is made of plastic. The second lens 12 has an object side surface 12a facing the object side and an image side surface 12b facing the image side, where the object side surface 12a is convex and the image side surface 12b is convex, and both surfaces 12a and 12b are aspherical.

The third lens 13 has a positive refractive power, and its material is plastic. The third lens 13 has an object side surface 13a facing the object side and an image side surface 13b facing the image side, and both surfaces 13a and 13b are aspherical. Among them, the object side surface 13a of the third lens 13 is convex at the low optical axis (labeled I in the figure) and concave at the distance away from the optical axis; and the image side 13b is convex at the low optical axis and away from the optical axis It is convex.

The fourth lens 14 has a negative refractive power, and its material is plastic. The fourth lens 14 has an object side surface 14a facing the object side and an image side surface 14b facing the image side, where the object side surface 14a is a concave surface and the image side surface 14b is a convex surface, and both surfaces 14a and 14b are aspherical surfaces.

The filter element 15 is disposed between the fourth lens 14 and the imaging surface 16, and its material is glass, and its surfaces 15a and 15b are both flat. The filter element 16 is, for example, an infrared filter element (IR Filter).

The curve equations of the aspheric surfaces of the above lenses are expressed as follows:

Among them, X: the distance between the point on the aspheric surface from the optical axis Y and the tangent plane between the aspheric surface and the optical axis; Y: the vertical distance between the point on the aspheric surface and the optical axis; R: the lens at the near optical axis Radius of curvature; K: cone coefficient; and Ai: i-th aspheric coefficient.

The effective focal length of the wide-angle imaging lens group 10 of the first embodiment is f, the aperture value (F-number) is Fno, the total length of the system (Total Track Length) is TTL, and half of the maximum angle of view is HFOV (Half Field of View). The values are as follows: f=0.761mm, Fno=3.4, TTL=2.87mm, HFOV=59.75 degrees.

The focal length of the first lens 11 is f1, and the focal length of the second lens 12 is f2, which satisfies the following condition: |f1/f2|=1.008.

The focal length of the fourth lens 14 is f4, which satisfies the following conditions: |f/f4|=0.132.

The thickness of the first lens 11 to the fourth lens 14 on the optical axis I are CT1, respectively CT2, CT3 and CT4, the distance between the image side surface 11b of the first lens 11 and the object side 12a surface of the second lens 12 on the optical axis I is AT1, which satisfies the following conditions: AT1/(CT1+CT2+CT3+CT4) =0.307.

The radius of curvature of the object side surface 11a and the image side surface 11b of the first lens 11 are R1 and R2, respectively, which satisfy the following conditions: (R1+R2)/(R1-R2)=2.619.

The dispersion coefficient of the third lens 13 is V3, and the dispersion coefficient of the fourth lens 14 is V4, which satisfies the following condition: V4/V3=0.383.

Please refer to Table 1 below, which is the detailed optical data of the wide-angle imaging lens group according to the first embodiment of the present invention. Among them, the object side surface 11a of the first lens 11 is marked as the surface 11a, the image side surface 11b is marked as the surface 11b, and the other lens surfaces are deduced by analogy. , It means that the surface is aspheric; the lens surface without ASP in the table means that the surface is spherical. The value in the distance field in the table represents the distance from the surface to the next surface. For example, the distance from the object side 11a to the image side 11b of the first lens 11 is 0.228 mm, which means that the thickness of the first lens 11 is 0.228 mm. The distance from the image side surface 11b of the first lens 11 to the aperture is 0.4 mm. The distance from the image side 12b of the second lens 12 to the object side 13a of the third lens 13 is 0.104 mm. Others can be deduced by analogy.

Please refer to Table 2, which is the aspherical coefficient of each lens surface in the first embodiment of the present invention. Among them, K is the cone coefficient in the aspheric curve equation, and A2 to A16 represent the 2nd to 16th order aspheric coefficients of each surface. For example, the taper coefficient K of the object side surface 11a of the first lens 11 is -0.0864. Others can be deduced by analogy. In addition, the tables of the following embodiments correspond to the wide-angle imaging lens groups of the embodiments, and the definitions of the tables are the same as those of the first embodiment, so they are not repeated in the following embodiments.

<Second Embodiment>

2A is a schematic diagram of a wide-angle imaging lens group according to a second embodiment of the invention. 2B is a longitudinal spherical aberration diagram (Longitudinal Spherical Aberration) of a wide-angle imaging lens group according to a second embodiment of the present invention. 2C is a field curve (Field Curve) aberration diagram of the wide-angle imaging lens group according to the second embodiment of the present invention. 2D is a distortion aberration diagram of a wide-angle imaging lens group according to a second embodiment of the present invention.

As shown in FIG. 2A, the wide-angle imaging lens group 20 of the second embodiment sequentially includes a first lens 21, an aperture ST, a second lens 22, a third lens 23, and a fourth lens 24 from the object side to the image side. Filter element 25 and imaging surface 26. Wherein, the wide-angle imaging lens group 20 can further be equipped with an electronic photosensitive element 200 (provided on the imaging surface 26) to form a wide-angle imaging device (not otherwise labeled).

The first lens 21 has a negative refractive power, and its material is glass. The first lens 21 has an object side surface 21a facing the object side and an image side surface 21b facing the image side, wherein the object side surface 21a is a convex surface and the image side surface 21b is a concave surface, and both surfaces 21a and 21b are aspherical surfaces.

The second lens 22 has positive refractive power and is made of glass. The second lens 22 has an object side surface 22a facing the object side and an image side surface 22b facing the image side, wherein the object side surface 22a is a convex surface, and the image side surface 22b is a concave surface, and both surfaces 22a and 22b are spherical surfaces.

The third lens 23 has a positive refractive power, and its material is plastic. The third lens 23 has an object side 23a facing the object side and an image side 23b facing the image side, wherein the object side 23a of the third lens 23 is convex, and the image side 23b is convex, and both surfaces 23a and 23b are Aspherical. .

The fourth lens 24 has a negative refractive power, and its material is plastic. The fourth lens 24 has an object side surface 24a facing the object side and an image side surface 24b facing the image side, wherein the object side surface 24a is a concave surface, The image side 24b is convex, and the two surfaces 24a and 24b are aspherical.

The filter element 25 is disposed between the fourth lens 24 and the imaging surface 26, and its material is glass, and its surface is flat. The filter element 26 is, for example, an infrared filter element (IR Filter).

The parameters of the wide-angle imaging lens group 20 of the second embodiment are the same as those of the first embodiment. For example, the effective focal length is f, the aperture value (F-number) is Fno, and half of the maximum angle of view is HFOV. Related parameters See Table 3 for numerical values.

Secondly, please refer to Table 4 and Table 5 below, where Table 4 is the detailed optical data of the wide-angle imaging lens group of the second embodiment of the present invention, and Table 5 is the aspherical surface coefficient of each lens surface of the second embodiment of the present invention .

<Third Embodiment>

3A is a schematic diagram of a wide-angle imaging lens group according to a third embodiment of the invention. 3B is a longitudinal spherical aberration diagram (Longitudinal Spherical Aberration) of a wide-angle imaging lens group according to a third embodiment of the present invention. 3C is a field curve (Field Curve) aberration diagram of the wide-angle imaging lens group according to the third embodiment of the present invention. FIG. 3D is a distortion aberration diagram of the wide-angle imaging lens group according to the third embodiment of the present invention.

As shown in FIG. 3A, the wide-angle imaging lens group 30 of the third embodiment sequentially includes a first lens 31, an aperture ST, a second lens 32, a third lens 33, and a fourth lens 34 from the object side to the image side. Filter element 35 and imaging surface 36. Wherein, the wide-angle imaging lens group 30 can further be equipped with an electronic photosensitive element 300 (provided on the imaging surface 36) to form a wide-angle imaging device (not otherwise labeled).

The first lens 31 has a negative refractive power, and its material is glass. The first lens 31 has an object side surface 31a facing the object side and an image side surface 31b facing the image side, wherein the object side surface 31a is convex and the image side surface 31b is concave, and both surfaces 31a and 31b are aspherical.

The second lens 32 has a positive refractive power and is made of plastic. The second lens 32 has an object side surface 32a facing the object side and an image side surface 32b facing the image side, wherein the object side surface 32a is convex and the image side 32b is convex, and both surfaces 32a and 32b are aspherical.

The third lens 33 has a positive refractive power, and its material is plastic. The third lens 33 has an object side 33a facing the object side and an image side 33b facing the image side, wherein the object side 33a of the third lens 33 is convex, and the image side 33b is convex, and both surfaces 33a and 33b are Aspherical.

The fourth lens 34 has negative refractive power and is made of plastic. The fourth lens 34 has an object side surface 34a facing the object side and an image side surface 34b facing the image side, and both surfaces 34a and 34b are aspherical. Among them, the object side surface 34a is a concave surface at the near optical axis and a concave surface away from the optical axis, while the image side surface 34b is a convex surface at the near optical axis and a concave surface away from the optical axis.

The filter element 35 is disposed between the fourth lens 34 and the imaging surface 36, and its material is glass, and its surface is flat. The filter element 36 is, for example, an infrared filter element (IR Filter).

The parameter definition of the wide-angle imaging lens group 30 of the third embodiment is the same as that of the first embodiment, for example, the effective focal length is f, the aperture value (F-number) is Fno, and one of the maximum angle of view Half of them are HFOV, etc., please refer to Table 6 for relevant parameter values.

Secondly, please refer to Table 7 and Table 8 below, where Table 7 is the detailed optical data of the wide-angle imaging lens group of the third embodiment of the present invention, and Table 8 is the aspherical surface coefficient of each lens surface of the third embodiment of the present invention .

<Fourth Embodiment>

4A is a schematic diagram of a wide-angle imaging lens group according to a fourth embodiment of the invention. 4B is a longitudinal spherical aberration diagram (Longitudinal Spherical Aberration) of a wide-angle imaging lens group according to a fourth embodiment of the present invention. 4C is a field curve (Field Curve) aberration diagram of the wide-angle imaging lens group according to the fourth embodiment of the present invention. 4D is a distortion aberration diagram of a wide-angle imaging lens group according to a fourth embodiment of the invention.

As shown in FIG. 4A, the wide-angle imaging lens group 40 of the fourth embodiment sequentially includes a first lens 41, an aperture ST, a second lens 42, a third lens 43, and a fourth lens 44 from the object side to the image side. Filter element 45 and imaging surface 46. Among them, the wide-angle imaging lens group 40 can be matched An electronic photosensitive element 400 (disposed on the imaging surface 46) to form a wide-angle imaging device (not otherwise labeled).

The first lens 41 has a negative refractive power, and its material is plastic. The first lens 41 has an object side surface 41a facing the object side and an image side surface 41b facing the image side, where the object side surface 41a is convex and the image side surface 41b is concave, and both surfaces 41a and 41b are aspherical.

The second lens 42 has a positive refractive power, and its material is plastic. The second lens 42 has an object side surface 42a facing the object side and an image side surface 42b facing the image side, wherein the object side surface 42a is a convex surface, and the image side surface 42b is a convex surface, and both surfaces 42a and 42b are spherical surfaces.

The third lens 43 has a positive refractive power, and its material is plastic. The third lens 43 has an object side surface 43a facing the object side and an image side surface 43b facing the image side, wherein the object side surface 43a of the third lens 43 is a convex surface, and the image side surface 43b is a convex surface, and both surfaces 43a and 43b are Aspherical. .

The fourth lens 44 has a negative refractive power, and its material is plastic. The fourth lens 44 has an object side surface 44a facing the object side and an image side surface 44b facing the image side, wherein the object side surface 44a is a concave surface and the image side surface 44b is a convex surface, and both surfaces 44a and 44b are aspherical surfaces.

The filter element 45 is disposed between the fourth lens 44 and the imaging surface 46, and its material is glass, and its surfaces are all flat. The filter element 46 is, for example, an infrared filter element (IR Filter).

The parameters of the wide-angle imaging lens group 40 of the fourth embodiment are the same as those of the first embodiment. For example, the effective focal length is f, the aperture value (F-number) is Fno, and the half of the maximum angle of view is HFOV. See Table 9 for numerical values.

Secondly, please refer to Table 10 and Table 11 below, where Table 10 is the detailed optical data of the wide-angle imaging lens group of the fourth embodiment of the present invention, and Table 11 is the non-linearity of each lens surface of the fourth embodiment of the present invention. Spherical coefficient.

<Fifth Embodiment>

5A is a schematic diagram of a wide-angle imaging lens group according to a fifth embodiment of the invention. 5B is a longitudinal spherical aberration diagram (Longitudinal Spherical Aberration) of a wide-angle imaging lens group according to a fifth embodiment of the present invention. FIG. 5C is a field curve aberration diagram of the wide-angle imaging lens group of the fifth embodiment of the present invention. FIG. 5D is a distortion aberration diagram of the wide-angle imaging lens group of the fifth embodiment of the present invention.

As shown in FIG. 5A, the wide-angle imaging lens group 50 of the fifth embodiment includes, in order from the object side to the image side, a first lens 51, an aperture ST, a second lens 52, a third lens 53, and a fourth lens The mirror 54, the filter element 55, and the imaging surface 56. Wherein, the wide-angle imaging lens group 50 can further be equipped with an electronic photosensitive element 500 (arranged on the imaging surface 56) to form a wide-angle imaging device (not otherwise labeled).

The first lens 51 has a negative refractive power, and its material is plastic. The first lens 51 has an object side surface 51a facing the object side and an image side surface 51b facing the image side, wherein the object side surface 51a is convex, and the image side surface 51b is concave, and both surfaces 51a and 51b are aspherical.

The second lens 52 has a positive refractive power and is made of plastic. The second lens 52 has an object side surface 52a facing the object side and an image side surface 52b facing the image side, wherein the object side surface 52a is convex, and the image side surface 52b is concave, and both surfaces 52a and 52b are aspherical.

The third lens 53 has a positive refractive power and is made of plastic. The third lens 53 has an object side surface 53a facing the object side and an image side surface 53b facing the image side, wherein the object side surface 53a of the third lens 53 is convex, and the image side surface 53b is convex, and both surfaces 53a and 53b are Aspherical. .

The fourth lens 54 has a negative refractive power, and its material is plastic. The fourth lens 54 has an object side surface 54a facing the object side and an image side surface 54b facing the image side, wherein the object side surface 54a is a concave surface, and the image side surface 54b is a convex surface, and both surfaces 54a and 54b are aspherical surfaces.

The filter element 55 is disposed between the fourth lens 54 and the imaging surface 56. The material of the filter element 55 is glass, and its surface is flat. The filter element 56 is, for example, an infrared filter element (IR Filter).

The parameters of the wide-angle imaging lens group 50 of the fifth embodiment are the same as those of the first embodiment. For example, the effective focal length is f, the aperture value (F-number) is Fno, and the half of the maximum angle of view is HFOV. Refer to Table 12 for numerical values.

Secondly, please refer to Table 13 and Table 14 below, where Table 13 is the detailed optical data of the wide-angle imaging lens group of the fifth embodiment of the invention, and Table 14 is the surface of each lens of the fifth embodiment of the invention Coefficient of aspheric surface.

<Sixth Embodiment>

6A is a schematic diagram of a wide-angle imaging lens group according to a sixth embodiment of the invention. 6B is a longitudinal spherical aberration diagram (Longitudinal Spherical Aberration) of the wide-angle imaging lens group according to the sixth embodiment of the present invention. 6C is a field curvature of a wide-angle imaging lens group according to a sixth embodiment of the present invention (Field Curve) aberration diagram. 6D is a distortion aberration diagram of the wide-angle imaging lens group according to the sixth embodiment of the present invention.

As shown in FIG. 6A, the wide-angle imaging lens group 60 of the sixth embodiment includes a first lens 61, an aperture ST, a second lens 62, a third lens 63, and a fourth lens 64 in order from the object side to the image side. Filter element 65 and imaging surface 66. Wherein, the wide-angle imaging lens group 60 can further be equipped with an electronic photosensitive element 600 (provided on the imaging surface 66) to form a wide-angle imaging device (not otherwise labeled).

The first lens 61 has a negative refractive power, and its material is plastic. The first lens 61 has The object side surface 61a facing the object side and the image side surface 61b facing the image side, wherein the object side surface 61a is convex and the image side surface 61b is concave, and both surfaces 61a and 61b are aspherical.

The second lens 62 has positive refractive power and is made of glass. The second lens 62 has an object side surface 62a facing the object side and an image side surface 62b facing the image side, and both surfaces 62a and 62b are aspherical. Among them, the object side surface 62 is a convex surface at the near optical axis and a convex surface away from the optical axis, and the image side surface 62b is a convex surface at the near optical axis and a concave surface away from the optical axis.

The third lens 63 has a positive refractive power, and its material is plastic. The third lens 63 has an object side 63a facing the object side and an image side 63b facing the image side, wherein the object side 63a of the third lens 63 is convex and the image side 63b is convex, and both surfaces 63a and 63b are Aspherical. .

The fourth lens 64 has a negative refractive power, and its material is plastic. The fourth lens 64 has an object side surface 64a facing the object side and an image side surface 64b facing the image side, wherein the object side surface 64a is a concave surface, and the image side surface 64b is a convex surface, and both surfaces 64a and 64b are aspherical surfaces.

The filter element 65 is disposed between the fourth lens 64 and the imaging surface 66, and its material is glass, and its surface is flat. The filter element 66 is, for example, an infrared filter (IR Filter).

The parameters of the wide-angle imaging lens group 60 of the sixth embodiment are the same as those of the first embodiment. For example, the effective focal length is f, the aperture value (F-number) is Fno, and the half of the maximum angle of view is HFOV. See Table 15 for numerical values.

Secondly, please refer to Table 16 and Table 17 below, where Table 16 is the detailed optical data of the wide-angle imaging lens group of the sixth embodiment of the invention, and Table 17 is the surface of each lens of the sixth embodiment of the invention Coefficient of aspheric surface.

<Seventh Embodiment>

The seventh embodiment of the present invention is an imaging device (not shown). The imaging device includes the wide-angle imaging lens group as in the foregoing embodiment, and an electronic photosensitive element.

<Eighth Embodiment>

The eighth embodiment of the present invention is an electronic device (not shown). The electronic device includes the imaging device as the seventh embodiment.

Although the present invention is described using the foregoing several embodiments, these embodiments are not intended to limit the scope of the present invention. For anyone who is familiar with this art, without departing from the spirit and scope of the present invention, various changes in form and details can still be made with reference to the contents of the embodiments disclosed in the present invention. It should be understood here that the present invention is subject to the scope defined in the following patent application, and any changes made within the scope of the patent application or its equivalent should still fall within the scope of the patent of the present invention.

10‧‧‧Wide-angle imaging lens group

100‧‧‧Electronic photosensitive element

11‧‧‧ First lens

11a‧‧‧Object side of the first lens

11b‧‧‧Image side of the first lens

12‧‧‧Second lens

12a‧‧‧Object side of the second lens

12b‧‧‧Image side of the second lens

13‧‧‧third lens

13a‧‧‧Object side of third lens

13b‧‧‧Image side of third lens

14‧‧‧ Fourth lens

14a‧‧‧Object side of fourth lens

14b‧‧‧Image side of fourth lens

15‧‧‧filter element

16‧‧‧Imaging surface

I‧‧‧optic axis

ST‧‧‧ Aperture

Claims (13)

A wide-angle imaging lens group includes, in order from the object side to the image side, a first lens with negative refractive power, the first lens includes an object side and an image side, and the object side of the first lens is Convex surface, the image side of the first lens is concave; an aperture; a second lens with positive refractive power, the second lens includes an object side and an image side, and the object side of the second lens is convex A third lens with positive refractive power, the third lens includes an object side and an image side, and the image side of the third lens is convex; and a fourth lens with negative refractive power, the fourth The lens includes an object side and an image side, the object side of the fourth lens is concave, and the image side of the fourth lens is convex; and the wide-angle imaging lens group satisfies the following conditions: 0.5<|f1/f2| <1.2; and 0.1<|f/f4|<1.2. Where f is the effective focal length of the wide-angle imaging lens group, f1 is the focal length of the first lens, f2 is the focal length of the second lens, and f4 is the focal length of the fourth lens. A wide-angle imaging lens group as claimed in item 1 of the patent application, wherein the thicknesses of the first lens to the fourth lens on the optical axis are CT1, CT2, CT3, and CT4, respectively, and the image side of the first lens The distance from the object side of the second lens on the optical axis is AT1, and the wide-angle imaging lens group satisfies the following condition: 0.1<AT1/(CT1+CT2+CT3+CT4)<0.42. For example, the wide-angle imaging lens group of claim 1 of the patent scope, wherein the radius of curvature of the object side and the image side of the first lens are R1 and R2, respectively, and the wide-angle imaging lens group satisfies the following conditions: 1<( R1+R2)/(R1-R2)<2.7. For example, the wide-angle imaging lens group according to item 1 of the patent application, in which the dispersion coefficient of the third lens is V3 and the dispersion coefficient of the fourth lens is V4, the wide-angle imaging lens group satisfies the following conditions: 0.2<V4/ V3<0.5. For example, the wide-angle imaging lens group according to item 1 of the patent application range, wherein one half of the maximum angle of view of the wide-angle imaging lens group is HFOV, which satisfies the following conditions: 45 degrees <HFOV <85 degrees. For example, the wide-angle imaging lens group according to item 1 of the patent application, wherein the image side of the second lens is convex. A wide-angle imaging lens group as claimed in item 6 of the patent scope, wherein the image side of the second lens is concave at a distance from the optical axis. For example, the wide-angle imaging lens group according to item 1 of the patent application, wherein the image side of the second lens is concave. For example, the wide-angle imaging lens group according to item 1 of the patent application, wherein the object side of the third lens is convex. For example, the wide-angle imaging lens group according to item 1 of the patent application scope, wherein the object side surfaces and the image side surfaces of the first lens to the fourth lens are all aspherical. For example, the wide-angle imaging lens group in claim 2 of the patent scope, wherein the wide-angle imaging lens group further satisfies the following conditions: 0.1<|f/f4|<1. An imaging device including: a wide-angle imaging lens group as claimed in item 1 of the patent scope. An electronic device including: an imaging device as claimed in item 12 of the patent scope.

Images