TWI761625B - Lens and fabrication method thereof - Google Patents

Abstract

A lens includes a first lens group, a second lens group having a positive refractive power, and an aperture disposed between the first lens group and the second lens group. The first lens group includes at least two lenses having refractive power, and the second lens group includes a doublet lens. The number of lenses having refractive power is greater than 4 and less than 11, D is the lens surface diameter of the second lens group farthest from the first lens group, and LT is the lens surface of the first lens group farthest from the second lens group, to the lens surface of the second lens group is farthest from the first lens group, the length in the lens axis. The lens satisfies the following conditions: 7 mm＜D＜25 mm and 0.3＜D/LT＜0.5.

Description

Lens and method of making the same

The present invention relates to a lens and a manufacturing method thereof.

In recent years, with the development of science and technology, the types of lenses have become more and more diverse, and the car lens used in vehicles is a common lens. At present, the requirements for thinning and optical performance are getting higher and higher. To meet such requirements, lenses generally need to have the characteristics of low cost, high resolution, large aperture, large target surface, wide operating temperature range and light weight. Therefore, there is currently a need for an imaging lens design that takes into account light weight, and can provide lower manufacturing costs, a wide operating temperature range, and better imaging quality.

The "prior art" paragraph is only used to help understand the present disclosure, so the content disclosed in the "prior art" paragraph may contain some that do not constitute the prior art known to those with ordinary skill in the art. The content disclosed in the "Prior Art" paragraph does not represent the content or the problem to be solved by one or more embodiments of the present invention, and has been known or recognized by those with ordinary knowledge in the technical field before the application of the present invention.

Other objects and advantages of the present invention can be further understood from the technical features disclosed in the embodiments of the present invention.

According to an aspect of the present invention, there is provided a lens including a first lens group and a second lens group having a positive refractive power, and an aperture set between the first lens group and the second lens group. The first lens group includes at least two lenses with diopter, and the second lens group includes a doublet lens. The lens includes the number of lenses with diopters greater than 4 and less than 11, D is the diameter of the lens surface of the second lens group farthest from the first lens group, LT is the lens surface of the first lens group farthest from the second lens group, to the second lens group The length of the lens group farthest from the lens surface of the first lens group on the optical axis of the lens. The lens meets the following conditions: 7 mm < D < 25 mm and 0.3 < D/LT < 0.5. Since the two positive diopter lens groups and the rear lens group in this embodiment include doublet lenses, and the number of lenses of the lens is between 5 and 10, light weight, lower manufacturing cost, wide operating temperature range, and better performance are achieved. Image quality acquisition lens design.

According to another aspect of the present invention, there is provided a lens comprising a first lens, a second lens, a combined lens composed of at least two mirrors, and an aspherical lens sequentially arranged along an image magnification side to an image reduction side, wherein the combined lens includes Corresponding adjacent surfaces with approximately the same or similar radii of curvature, and the lens includes lenses with a refractive power greater than 4 and less than 11, wherein LT is the lens surface of the first lens close to the image magnification side, to the aspheric lens close to the image reduction side lens Surface, the length on the optical axis of the lens, IMH25 is the image height of the lens half-angle of view 25 degrees on the imaging plane, IMH45 is the image height of the lens half-angle of view 45 degrees on the imaging plane, the lens also meets the following conditions: LT/ IMH25<12 and LT/IMH45<6.5. By including at least two lenses, a combination lens and an aspherical lens in this embodiment, and the number of lenses of the lens is between 5 and 10, it achieves the advantages of light weight, lower manufacturing cost, wide operating temperature range and better imaging quality. Taking lens design.

According to yet another aspect of the present invention, there is provided a lens including a first lens group and a second lens group having a positive refractive power. The first lens group includes a first lens and a second lens, and the second lens group includes a combined lens composed of at least two mirrors and an aspherical lens. D is the diameter of the lens surface of the second lens group farthest from the first lens group, and the lens satisfies the following conditions: 7 mm < D < 25 mm, and the illumination value at the highest point of the image height on the imaging surface of the lens, and the optical axis on the imaging surface The ratio of the lighting value of the position, greater than 35%. Since the two positive diopter lens groups and the rear lens group in this embodiment include a combination lens, and the number of lenses is between 5 and 10, it achieves light weight, lower manufacturing cost, wide operating temperature range and better imaging. High quality imaging lens design.

Through the design of the embodiments of the present invention, an image capture capable of achieving both good optical imaging quality, miniaturization and light weight of an optical lens, lower manufacturing cost and better imaging quality can be provided. lens design. Furthermore, the working temperature range of the embodiment of the present invention can be from -40°C to 105°C and the optical lens is designed with 5 to 10 lenses, so it can provide low cost, large aperture, high resolution, light weight, wide Operating temperature range and other characteristics, and can provide an optical lens design with lower manufacturing costs and better imaging quality.

Other objects and advantages of the present invention can be further understood from the technical features disclosed in the present invention. In order to make the above-mentioned and other objects, features and advantages of the present invention more obvious and easy to understand, the following specific embodiments are given in conjunction with the accompanying drawings, and are described in detail as follows.

The foregoing and other technical contents, features and effects of the present invention will be clearly presented in the following detailed description of the embodiments with reference to the drawings. The directional terms mentioned in the following embodiments, such as: up, down, left, right, front or rear, etc., are only for referring to the directions of the attached drawings. Accordingly, the directional terms used are illustrative and not limiting of the present invention. In addition, the terms "first" and "second" used in the following embodiments are used to identify the same or similar elements, and are not used to limit the elements.

The so-called optical element in the present invention means that the element is made of partially or totally reflective or penetrating material, usually including glass or plastic. For example, a lens, a lens, or an aperture.

When the lens is used in an imaging system, the image magnification side refers to the side on the optical path that is close to the object to be photographed, and the image reduction side refers to the side closer to the photosensitive element on the optical path.

The object side (or image side) of a lens has a convex surface (or concave surface) located in a certain area, which means that the area is more "direction parallel to the optical axis" than the outer area adjacent to the area in the radial direction. convex" (or "concave inward").

FIG. 1 is a schematic diagram of a lens structure according to a first embodiment of the present invention. Referring to FIG. 1, in this embodiment, the lens 10a has a lens barrel (not shown), and the lens barrel is arranged from the first side (image enlargement side OS) to the second side (image reduction side IS) including the first Lens L1, second lens L2, third lens L3, aperture 14, fourth lens L4, fifth lens L5, sixth lens L6, seventh lens L7, and eighth lens L8. The first lens L1, the second lens L2, and the third lens L3 constitute a first lens group (eg, a front group) 20 having positive refractive power, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a seventh lens L7 and the eighth lens L8 may constitute a second lens group (eg, a rear group) 30 having positive refractive power. Furthermore, the image reduction side IS can be provided with a filter 16, a glass cover 18 and an image sensor (not shown in the figure). It is located between the second lens group 30 and the imaging surface 19 on the effective focal length of visible light. In this embodiment, the dioptric powers of the first lens L1 to the eighth lens L8 are negative, negative, positive, positive, positive, negative, positive, and negative, respectively, and the second lens and the eighth lens are aspherical glass lenses. In one embodiment, the aspherical glass lens may be replaced with an aspherical plastic lens. In addition, the two adjacent surfaces of the two lenses have approximately or exactly the same radius of curvature and form a doublet or triplet. For example, the fifth lens L5 and the sixth lens L6 in this embodiment can form a doublet lens, but the embodiment of the present invention is not limited thereto. In each specific embodiment of the present invention, the image enlargement side OS is set on the left side of each figure, and the image reduction side IS is set on the right side of each figure, which will not be described repeatedly.

The aperture 14 in the present invention refers to an aperture stop (Aperture Stop), and the aperture is an independent element or integrated on other optical elements. In this embodiment, the aperture uses a mechanism to block the peripheral light and retain the middle portion to transmit light to achieve a similar effect, and the aforementioned mechanism may be adjustable. The so-called adjustable refers to the adjustment of the position, shape or transparency of the mechanical components. Alternatively, the aperture can also be coated with opaque light-absorbing material on the surface of the lens, so that the central part of the lens can be retained to transmit light to limit the light path.

Each lens system defines a diameter of a surface. For example, as shown in FIG. 1 , the diameter of the surface refers to the distance between the mirror turning points P and Q at both ends of the optical axis 12 in the direction perpendicular to the optical axis 12 (eg, the diameter D1 of the surface). Furthermore, in this embodiment, the diameter of the surface S1 is 11.99 mm, and the diameter of the surface S16 is 9.74 mm.

(1) 上述的公式(1)中，Z為光軸方向之偏移量（sag），c是密切球面（osculating sphere）的半徑之倒數，也就是接近光軸處的曲率半徑的倒數，k是二次曲面係數（conic），r是非球面高度，即為從透鏡中心往透鏡邊緣的高度。表二的A-F分別代表非球面多項式的 4、6、8、10、12、14階項係數值。然而，下文中所列舉的資料並非用以限定本發明，任何所屬領域中具有通常知識者在參照本發明之後，當可對其參數或設定作適當的更動，惟其仍應屬於本發明的範疇內。The lens design parameters, shape and aspheric coefficient of the lens 10a are shown in Table 1 and Table 2, respectively. In the design example of the present invention, the aspheric polynomial can be expressed by the following formula:

(1) In the above formula (1), Z is the offset in the direction of the optical axis (sag), c is the inverse of the radius of the osculating sphere, that is, the inverse of the radius of curvature near the optical axis, k is the quadratic surface coefficient (conic), and r is the height of the aspheric surface, which is the height from the center of the lens to the edge of the lens. AF in Table 2 represents the coefficient values of the 4th, 6th, 8th, 10th, 12th, and 14th order terms of the aspheric polynomial, respectively. However, the information listed below is not intended to limit the present invention. Any person with ordinary knowledge in the art can make appropriate changes to the parameters or settings after referring to the present invention, but they still belong to the scope of the present invention. .

Table I

Table II

The distance of S1 is the distance between the surfaces S1 and S2 on the optical axis 12, the distance of S2 is the distance from the surface S2 to S3 on the optical axis 12, and the distance of S20 is the distance from the surface S20 to the visible light effective focal length on the imaging plane 19 on the optical axis 12.

The appearance of * on the surface in the table means that the surface is an aspheric surface, and if it is not marked, it means a spherical surface.

The radius of curvature refers to the inverse of the curvature. When the radius of curvature is positive, the spherical center of the lens surface is in the direction of the image reduction side of the lens. When the radius of curvature is negative, the spherical center of the lens surface is in the direction of the image magnification side of the lens. The convex and concave of each lens can be seen in the table above.

The aperture value of the present invention is represented by F/#, as indicated in the table above. When the lens of the present invention is applied to a projection system, the imaging surface is the surface of the light valve. When the lens is used in the imaging system, the imaging surface refers to the surface of the photosensitive element.

When the lens is used in an imaging system, the image height IMH refers to 1/2 of the length of the image circle on the imaging plane, as indicated in the table above.

In the present invention, the total length of the lens is represented by LT, as indicated in the above table. More specifically, the total length of this embodiment refers to the distance measured along the optical axis 12 between the optical surface S1 closest to the image enlargement side and the optical surface S16 closest to the image reduction side of the lens 10a, as indicated in the table above. . The total lens length (LT) of the lens is less than 30mm.

In this embodiment, the field of view angle FOV refers to the light-receiving angle of the optical surface S1 closest to the magnifying end of the image, that is, the field of view measured diagonally, as indicated in the table above.

In this embodiment, IMH25 is the image height of the lens with a half field of view (FOV) of 25 degrees on the imaging plane 19, and IMH45 is the image height of the lens with a half field of view (FOV) of 45 degrees on the imaging plane 19, as shown in the table above. indicated.

In this embodiment, the ratio of the effective focal length of the lens to the effective focal length of the first lens group (front group) is 0.09, and the ratio of the effective focal length of the lens to the effective focal length of the second lens group (rear group) is 0.46.

The lens of an embodiment of the present invention includes two lens groups. For example, the front group may use two lenses with negative refractive power, including an aspherical lens to have light-receiving ability, but it is not limited. The f-stop of the lens falls around 2.2. The rear group includes a doublet lens (cemented lens, combined lens) and an aspherical lens to correct aberration and chromatic aberration, and the doublet lens makes the minimum distance along an optical axis between the two lenses in the rear group less than 0.05mm. For example, a doublet lens can be replaced by a triplet lens, which is not limited. Doublets, cemented lenses, combined lenses, and triplets all include corresponding adjacent surfaces having about the same or similar radii of curvature. The total number of lenses with diopter is 5~10, and the entrance pupil diameter (phi) of the lens is greater than 2mm. For example, the diameter of the entrance pupil in this embodiment is about 2.23, and the lens can have at least two Abbe numbers greater than 65 lens.

In one embodiment, the lens surface of the lens can satisfy 7 mm<D<25 mm, in another embodiment, it can satisfy 8 mm<D<20 mm, and in yet another embodiment, it can satisfy 8.5 mm<D<15 mm , where D is the diameter of the lens surface closest to the imaging surface of the lens, so that the image light entering the lens converges to a size close to the image sensor, so as to obtain better optical effects in a limited space.

In one embodiment, the lens may satisfy 0.3<D/LT<0.5, in another embodiment may satisfy 0.32<D/LT<0.48, and in yet another embodiment may satisfy 0.35<D/LT<0.47, thereby providing The image sensor corresponds to the preferred design range of the total length of the lens, where D is the diameter of the lens surface closest to the imaging surface of the lens, LT is the surface of the first lens of the lens facing the image magnifying side OS, and the last lens facing the image reduction The length of the surface of the side IS on an optical axis.

In one embodiment, the lens may satisfy LT/IMH25<12, and LT/IMH45<6.5, in another embodiment, may satisfy LT/IMH25<11.8, and LT/IMH45<6.4, and in yet another embodiment may satisfy LT/IMH25<11.6, and LT/IMH45<6.3, in order to provide a better design range of the image sensor corresponding to the total length of the lens, where LT is the lens surface of the first lens close to the image magnification side, to the aspheric lens close to the image reduction side The length of the lens surface on the optical axis of the lens, IMH25 is the image height of the lens half-angle of view 25 degrees on the imaging surface, IMH45 is the image height of the lens half-angle of view 45 degrees on the imaging surface.

In one embodiment, the ratio of the illumination value at the position of the highest point of the image height on the imaging surface of the lens to the illumination value at the position of the optical axis on the imaging surface is greater than 35%. In another embodiment, the ratio of the illumination value at the position of the highest point of the image height on the imaging surface of the lens to the illumination value at the position of the optical axis on the imaging surface is greater than 38%. In another embodiment, the ratio of the illumination value at the position of the highest point of the image height on the imaging surface of the lens to the illumination value at the position of the optical axis on the imaging surface is greater than 40%.

The design of the second embodiment of the lens of the present invention will be described below. FIG. 5 is a schematic structural diagram of the lens 10b according to the second embodiment of the present invention. In this embodiment, the dioptric powers of the first lens L1 to the seventh lens L7 of the lens 10b are respectively negative, negative, positive, negative, positive, positive and negative, all the lenses are glass lenses, and the second lens L2 and the third lens are The seven lenses L7 are aspherical lenses. In this embodiment, the aspherical lenses can be made of glass. In one embodiment, the aspherical glass lens may be replaced by an aspherical plastic lens. Furthermore, in this embodiment, the diameter of the surface S1 is 12 mm, and the diameter of the surface S14 is 10.23 mm. The design parameters of the lens and its peripheral elements in the lens 10b are shown in Table 3.

Table 3

Table 4 lists the values of the aspheric coefficients and quadric coefficients of each order of the aspheric lens surface of the lens in the second embodiment of the present invention.

Table 4

The distance of S1 is the distance between the surfaces S1 and S2 on the optical axis 12, the distance of S2 is the distance from the surface S2 to S3 on the optical axis 12, and the distance of S18 is the distance from the surface S18 to the visible light effective focal length on the imaging plane 19 on the optical axis 12. The entrance pupil diameter (phi) of the lens is greater than 2 mm, for example, the entrance pupil diameter of the present embodiment is about 2.25, and the lens may have at least two lenses with Abbe numbers greater than 65.

In this embodiment, the ratio of the effective focal length of the lens to the effective focal length of the first lens group (front group) is 0.02, and the ratio of the effective focal length of the lens to the effective focal length of the second lens group (rear group) is 0.6.

The design of the third embodiment of the lens of the present invention will be described below. FIG. 9 is a schematic structural diagram of a lens 10c according to a third embodiment of the present invention. In this embodiment, the dioptric powers of the first lens L1 to the seventh lens L7 of the lens 10c are respectively negative, negative, positive, positive, negative, positive, and negative, all the lenses are glass lenses, and the first lens L1 and the third lens are The seven lenses L7 are aspherical lenses. In this embodiment, the aspherical lenses can be made of glass. In one embodiment, the aspherical glass lens may be replaced by an aspherical plastic lens. Furthermore, in this embodiment, the diameter of the surface S1 is 12.2 mm, and the diameter of the surface S14 is 9.38 mm. The design parameters of the lens in the lens 10c and its peripheral elements are shown in Table 5.

Table 5

Table 6 lists the values of the aspheric coefficients and quadric coefficients of each order of the aspheric lens surface of the lens in the third embodiment of the present invention.

Table 6

The distance of S1 is the distance between the surfaces S1 and S2 on the optical axis 12, the distance of S2 is the distance from the surface S2 to S3 on the optical axis 12, and the distance of S18 is the distance from the surface S18 to the visible light effective focal length on the imaging plane 19 on the optical axis 12. The entrance pupil diameter (phi) of the lens is greater than 2 mm, for example, the entrance pupil diameter of the present embodiment is about 2.09, and the lens may have at least two lenses with Abbe numbers greater than 65.

In this embodiment, the ratio of the effective focal length of the lens to the effective focal length of the first lens group (front group) is 0.26, and the ratio of the effective focal length of the lens to the effective focal length of the second lens group (rear group) is 0.39.

The design of the fourth embodiment of the lens of the present invention will be described below. FIG. 13 is a schematic structural diagram of a lens 10d according to a fourth embodiment of the present invention. In this embodiment, the dioptric powers of the first lens L1 to the seventh lens L7 of the lens 10d are negative, negative, positive, negative, positive, positive, and negative, respectively, all the lenses are glass lenses, and the seventh lens L7 is not. The spherical lens, in this embodiment, the aspherical lens can be made by molding glass. In one embodiment, the aspherical glass lens may be replaced by an aspherical plastic lens. In this embodiment, the glass cover is removed to reduce the cost. Furthermore, in this embodiment, the diameter of the surface S1 is 12.22 mm, and the diameter of the surface S14 is 8.67 mm. The design parameters of the lens in the lens 10d and its peripheral elements are shown in Table 7.

Table 7

Table 8 lists the values of the aspheric coefficients and quadric coefficients of each order of the aspheric lens surface of the lens in the fourth embodiment of the present invention.

Table 8

The distance of S1 is the distance between the surfaces S1 and S2 on the optical axis 12, the distance of S2 is the distance from the surface S2 to S3 on the optical axis 12, and the distance of S16 is the distance from the surface S16 to the visible light effective focal length on the imaging plane 19 on the optical axis 12. The entrance pupil diameter (phi) of the lens is greater than 2 mm, for example, the entrance pupil diameter of the present embodiment is about 2.45, and the lens may have at least two lenses with Abbe numbers greater than 65.

In this embodiment, the ratio of the effective focal length of the lens to the effective focal length of the first lens group (front group) is 0.08, and the ratio of the effective focal length of the lens to the effective focal length of the second lens group (rear group) is 0.58.

The design of the fifth embodiment of the lens of the present invention will be described below. FIG. 17 is a schematic structural diagram of a lens 10e according to a fifth embodiment of the present invention. In this embodiment, the dioptric powers of the first lens L1 to the seventh lens L7 of the lens 10e are respectively negative, negative, positive, negative, positive, positive and negative, all the lenses are glass lenses, and the second lens L2 and the third lens are The seven lenses L7 are aspherical lenses. In this embodiment, the aspherical lenses can be made of glass. In one embodiment, the aspherical glass lens may be replaced with an aspherical plastic lens. The first lens L1, the second lens L2, and the third lens L3 constitute a first lens group (eg, a front group) 20 having negative refractive power, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a seventh lens L7 A second lens group (eg, a rear group) 30 having a positive refractive power is constituted. Furthermore, in this embodiment, the diameter of the surface S1 is 13.6 mm, and the diameter of the surface S14 is 9.49 mm. The design parameters of the lens and its peripheral elements in the lens 10e are shown in Table 9.

Table 9

Table 10 lists the values of the aspheric coefficients and quadric coefficients of each order of the aspheric lens surface of the lens in the fifth embodiment of the present invention.

Table 10

The distance of S1 is the distance between the surfaces S1 and S2 on the optical axis 12, the distance of S2 is the distance from the surface S2 to S3 on the optical axis 12, and the distance of S16 is the distance from the surface S16 to the visible light effective focal length on the imaging plane 19 on the optical axis 12. The entrance pupil diameter (phi) of the lens is greater than 2 mm, for example, the entrance pupil diameter of the present embodiment is about 2.33, and the lens may have at least two lenses with Abbe numbers greater than 65.

In this embodiment, the ratio of the effective focal length of the lens to the effective focal length of the first lens group (front group) is -0.06, and the ratio of the effective focal length of the lens to the effective focal length of the second lens group (rear group) is 0.55.

Figures 2-4, Figures 6-8, Figures 10-12, Figures 14-16 and Figures 18-20 are respectively the imaging optical simulation data diagrams of the lenses 10a, 10b, 10c, 10d and 10e of the embodiment. 2, 6, 10, 14 and 18 are ray fan plots of visible light of the lenses 10a, 10b, 10c, 10d and 10e of the embodiment, respectively, wherein the X-axis is the position of the light passing through the entrance pupil, and the Y-axis is The relative value of the position where the chief ray is projected to the image plane (eg, the imaging plane S19 ). Figures 3, 7, 11, 15, and 19 are the optical transfer function (MTF) simulation data graphs of the example lenses 10a, 10b, 10c, 10d, and 10e, respectively, and Figures 4, 8, 12, 16, and 20 are the example lenses, respectively Simulation data plot of the ratio of the illumination values at the tenth point position of the image height on the imaging surface of 10a, 10b, 10c, 10d and 10e to the illumination value at the position of the optical axis on the imaging surface. Figures 2-4, Figures 6-8, Figures 10-12, Figures 14-16, and Figures 18-20 show the graphs in the simulated data graphs are all within the standard range, so it can be verified that the lenses 10a, 10b, The 10c, 10d and 10e do indeed combine the characteristics of good optical imaging quality.

Through the design of the embodiments of the present invention, an image capture capable of achieving both good optical imaging quality, miniaturization and light weight of an optical lens, lower manufacturing cost and better imaging quality can be provided. lens design. Furthermore, the working temperature range of the embodiment of the present invention can be from -40°C to 105°C and the optical lens is designed with 5 to 10 lenses, so it can provide low cost, large aperture, high resolution, light weight, wide Operating temperature range and other characteristics, and can provide an optical lens design with lower manufacturing costs and better imaging quality.

The parameters in the tables listed in the above specific embodiments are only used for illustration, rather than limiting the present invention. Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the present invention The scope of protection shall be determined by the scope of the appended patent application. In addition, any embodiment of the present invention or the scope of the claims is not required to achieve all of the objects or advantages or features disclosed herein. The abstract section and the title are only used to assist the search of patent documents and are not intended to limit the scope of the present invention.

10a, 10b, 10c, 10d, 10e‧‧‧Lens 12‧‧‧Optical axis 14‧‧‧Aperture 16‧‧‧Filter 18‧‧‧Glass cover 19‧‧‧Imaging surface 20‧‧‧First lens Group 30‧‧‧Second Lens Group 200, 600, 1000, 1400, 1800‧‧‧Light Sector Diagram 300, 700, 1100, 1500, 1900‧‧‧Optical Transfer Function (MTF) Simulation Data Diagram L1-L8‧‧ ‧Lens S1-S21‧‧‧Surface P, Q‧‧‧Inflection point D1‧‧‧Diameter OS‧‧‧Image enlargement side IS‧‧‧Image reduction side

FIG. 1 is a schematic diagram of a lens 10a according to an embodiment of the present invention.

2 to 4 are respectively the ray fan diagram, the optical transfer function diagram of the lens 10a, and the ratio diagram of the illumination value at the tenth point of the image height on the imaging surface and the illumination value at the optical axis position on the imaging surface.

FIG. 5 is a schematic diagram of a lens 10b according to an embodiment of the present invention.

6 to 8 are respectively the ray fan diagram of the lens 10b, the optical transfer function diagram, and the ratio diagram of the illumination value at the tenth point of the image height on the imaging surface and the illumination value at the optical axis position on the imaging surface.

FIG. 9 is a schematic diagram of a lens 10c according to an embodiment of the present invention.

10 to 12 are respectively the ray fan diagram of the lens 10c, the optical transfer function diagram, and the ratio of the illumination value at the tenth point of the image height on the imaging surface to the illumination value at the optical axis position on the imaging surface.

FIG. 13 is a schematic diagram of a lens 10d according to an embodiment of the present invention.

14 to 16 are respectively the ray fan diagram of the lens 10d, the optical transfer function diagram, and the ratio of the illumination value at the tenth point of the image height on the imaging surface to the illumination value at the optical axis position on the imaging surface.

FIG. 17 is a schematic diagram of a lens 10e according to an embodiment of the present invention.

18 to 20 are respectively the ray fan diagram of the lens 10e, the optical transfer function diagram, and the ratio of the illumination value at the tenth point of the image height on the imaging surface to the illumination value at the optical axis position on the imaging surface.

none

10a‧‧‧Lens

12‧‧‧Optical axis

14‧‧‧Aperture

16‧‧‧Filters

18‧‧‧Glass cover

19‧‧‧Imaging surface

20‧‧‧First lens group

30‧‧‧Second lens group

L1-L8‧‧‧Lens

S1-S21‧‧‧Surface

P, Q‧‧‧Turning Point

D1‧‧‧diameter

OS‧‧‧image magnification side

IS‧‧‧Image reduction side

Claims (10)

A lens, comprising: a first lens group, including at least two lenses with diopter; a second lens group with a positive diopter, including a combined lens composed of at least two lenses; and an aperture set on the first lens Between the lens group and the second lens group; wherein the number of lenses with diopter included in the lens is greater than 4 and less than 11, D is the diameter of the lens surface of the second lens group farthest from the first lens group, LT is the first lens group A lens group farthest from the lens surface of the second lens group, to the second lens group farthest from the lens surface of the first lens group, the length on the optical axis of the lens, IMH25 is the half angle of view of the lens 25 degrees The image height of an imaging plane, IMH45 is the image height of the lens with a half angle of view of 45 degrees on the imaging plane, and the lens meets the following conditions: 7mm<D<25mm, 0.3<D/LT<0.5, LT/IMH25 <12, and LT/IMH45<6.5. The lens of claim 1, wherein the combined lens includes corresponding adjacent surfaces having about the same or similar radii of curvature. A lens, comprising: a first lens group, the first lens group includes a first lens and a second lens; and a second lens group with a positive refractive power, the second lens group includes a lens composed of at least two lenses A combined lens and an aspherical lens are formed, wherein D is the diameter of the lens surface of the second lens group farthest from the first lens group, LT is the lens surface of the first lens group farthest from the second lens group, to the The length of the second lens group farthest from the lens surface of the first lens group on the optical axis of the lens, IMH25 is the image height of the lens on an imaging plane with a half angle of view of 25 degrees, and IMH45 is the half angle of view of the lens The image height of 45 degrees on the imaging plane, the lens meets the following conditions: 7mm<D<25mm, LT/IMH25<12, and LT/IMH45<6.5, and the illumination value at the highest point of the image height on the lens imaging plane, The ratio of the illumination value at the position of the optical axis on the imaging plane, greater than 35%. The lens according to any one of claims 1-3, wherein the lens comprises at least 2 lenses whose Abbe number is less than 65. The lens of any one of claims 1-3, wherein the aperture value (F/#) of the lens is greater than or equal to 2.2. The lens of any one of claims 1-3, wherein the lens satisfies one of the following conditions: (1) between the first side or the image magnification side and the aperture, an aspherical lens is included, ( 2) Only one aspherical lens is included between the aperture and the second side or the image reduction side, (3) The material of all lenses is made of glass, (4) The diopter of the first lens group is positive , (5) the diopter of the first lens group is negative. The lens of any one of claims 1-3, wherein the lens has a total lens length (LT) of less than 30 mm. The lens of any one of claims 1 to 3, wherein the lens satisfies one of the following conditions: (1) from the first lens group or the image magnification side to the second lens group or the image reduction side in accordance with The order is convex-concave, aspherical, biconvex, biconvex, biconvex, biconcave, biconvex and aspherical lenses, (2) from the first lens group or the image enlargement side to the second lens group or the image reduction Convex, aspheric, biconvex, biconvex, biconvex, biconvex, and aspherical lenses in sequence, (3) from the first lens group or the image magnification side to the second lens group or the image reduction side The sides are sequentially aspherical, convex-concave, biconvex, biconvex, convex-concave, concave-convex and aspherical lenses, (4) sequentially from the first lens group or the image magnification side to the second lens group or the image reduction side For convex-concave, bi-concave, bi-convex, bi-concave, bi-convex, bi-convex, and aspheric lenses. The lens of any one of claims 1-3, wherein the lens satisfies one of the following conditions: (1) from the first lens group or the image magnification side to the second lens group or the image reduction side The lens diopter is sequentially negative, negative, positive, positive, positive, negative, positive and negative, (2) the lens diopter from the first lens group or the image magnification side to the second lens group or the image reduction side in sequence is negative, negative, positive, Negative, positive, positive and negative, (3) the lens diopter from the first lens group or the image magnification side to the second lens group or the image reduction side is in order negative, negative, positive, positive, negative, positive and negative . A lens manufacturing method, comprising: providing a lens barrel; inserting and fixing a first lens group with a positive refractive power and a second lens group with a positive refractive power in the lens barrel, wherein the first lens group includes At least two lenses with diopter, the second lens group includes a doublet lens; and an aperture, located between the first lens group and the second lens group, wherein the lens includes a number of diopter lenses: Greater than 4 and less than 11, D is the diameter of the lens surface of the second lens group farthest from the first lens group, LT is the lens surface of the first lens group farthest from the second lens group, to the second lens group the most The length of the lens surface away from the first lens group on the optical axis of the lens, IMH25 is the image height of the lens half angle of view 25 degrees on an imaging plane, IMH45 is the half angle of view of the lens 45 degrees in the imaging surface and the lens meets the following conditions: 7mm<D<25mm, 0.3<D/LT<0.5, LT/IMH25<12, and LT/IMH45<6.5.

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