TWI811987B - Optical lens - Google Patents

Abstract

An optical lens, applied to a headlamp, includes three lenses closest to the magnified side of the lens, in sequence a first lens with a positive refractive power, a second lens with a negative refractive power and a third lens. The three lenses include at least two aspherical lenses, and one of which has positive power, the other has negative power. The signs of the curvature radii of the aspheric lens with a positive refractive power are the same in a first direction and a second direction, and the first direction and the second direction are perpendicular to each other. The lens closest to the minified side of the lens and having a refractive power is a spherical glass lens. The full field of view(FOV) of the lens is between 25 and 45 degrees. The lens has at most five lenses.

Description

optical lens

The present invention relates to an optical lens, and in particular to an optical lens applicable to vehicle headlights.

The function of the car lights is not only to allow the driver to identify the environmental status ahead, but also to provide surrounding people with information about the driver's current location, and to achieve a considerable degree of warning effect. Currently, there are smart car lights on the market that adjust based on ambient light and driving conditions to reduce glare to oncoming vehicles, or project indicator images to assist driving. Therefore, there is currently a need for an optical lens that can take into account the lighting range required by traffic regulations and obtain good resolution and small distortion.

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

One embodiment of the present invention proposes an optical lens that can be applied to a car light, including three lenses closest to the magnification side of the lens, in order: a first lens with a positive diopter value, a second lens with a negative diopter value, and A third lens. The three lenses include at least two aspherical lenses, and the diopter value of the two aspherical lenses is positive and negative. The positive and negative values of the curvature radii of an aspherical lens with a positive diopter value are the same in a first direction and a second direction, and the first direction and the second direction are perpendicular to each other. The lens closest to the reduction side of the lens and having diopter is a spherical glass lens. The field of view of the lens is between 25 degrees and 45 degrees. And lenses include up to 5 lenses.

Another embodiment of the present invention provides an optical lens, which includes a first lens group, an aperture and a second lens group in order from the lens magnification side to the lens reduction side. The first lens group includes 1 to 2 lenses with diopter, wherein 1 to 2 lenses with diopter include a first aspherical lens. The second lens group includes 2 to 3 lenses with diopter, of which 2 to 3 lenses with diopter include a second aspherical lens and a spherical glass lens, and this spherical glass lens is closest to the reduction side of the lens and has diopter. of lenses. One of the diopter values of the first aspherical lens and the second aspherical lens is positive and the other is negative. The positive and negative values of the curvature radii of an aspherical lens with a positive diopter value are the same in a first direction and a second direction, and the first direction and the second direction are perpendicular to each other. The lens meets the following conditions: 25 degrees < FOV < 45 degrees, and FOV is the field of view of the lens; |EFL/BFL|>3, and EFL is the effective focal length of the lens, and BFL is the back focus length of the lens; and the lens contains at most 5 lenses.

Based on the above, the optical lens of the present invention has at least one of the following advantages. Through the design of the embodiments of the present invention, it can provide a lighting range that meets the requirements of traffic regulations, high resolution, low distortion, miniaturization and other characteristics, and can provide lower manufacturing costs and better imaging quality when applied to automobile headlights. lens design.

In order to make the above-mentioned features and advantages of the present invention more obvious and easy to understand, embodiments are given below and described in detail with reference to the accompanying drawings.

10; 10a-10l: Optical lens

12: Optical axis

14:Aperture

100:Projection device

120:Image source

130:稜顡

G1; G2: lens group

I:Image beam

L1-L5: Lens

S1-S10: Surface

OS: magnification side

IS: zoom side

FIG. 1 is a schematic diagram of a projection device according to an embodiment of the present invention.

FIG. 2 is an optical structural diagram of the optical lens according to the first embodiment of the present invention.

FIG. 3 is an optical structural diagram of an optical lens according to a second embodiment of the present invention.

FIG. 4 is an optical structural diagram of an optical lens according to a third embodiment of the present invention.

FIG. 5 is an optical structural diagram of an optical lens according to the fourth embodiment of the present invention.

FIG. 6 is an optical structural diagram of an optical lens according to the fifth embodiment of the present invention.

FIG. 7 is an optical structural diagram of an optical lens according to the sixth embodiment of the present invention.

FIG. 8 is an optical structural diagram of an optical lens according to the seventh embodiment of the present invention.

FIG. 9 is an optical structural diagram of an optical lens according to the eighth embodiment of the present invention.

FIG. 10 is an optical structural diagram of an optical lens according to the ninth embodiment of the present invention.

FIG. 11 is an optical structural diagram of an optical lens according to a tenth embodiment of the present invention.

FIG. 12 is an optical structural diagram of an optical lens according to an eleventh embodiment of the present invention.

FIG. 13 is an optical structural diagram of an optical lens according to the twelfth embodiment of the present invention.

FIG. 14 is a modulation transfer function curve diagram of the optical lens of FIG. 2 , and FIG. 15 is a distortion diagram of the optical lens of FIG. 2 .

FIG. 16 is a modulation transfer function curve diagram of the optical lens of FIG. 6 , and FIG. 17 is a distortion diagram of the optical lens of FIG. 6 .

FIG. 18 is a modulation transfer function curve diagram of the optical lens of FIG. 12 , and FIG. 19 is a distortion diagram of the optical lens of FIG. 12 .

20A and 20B are schematic three-dimensional views illustrating the appearance of a lens according to an embodiment of the present invention.

The terms "first" and "second" used in the following embodiments are for the purpose of identifying the same or similar technical contents, features and functions mentioned above in the present invention. In the following detailed description of the embodiments with reference to the drawings, , will be clearly displayed. components used. Directional terms mentioned in the following embodiments, such as up, down, left, right, front or back, etc., are only for reference to the directions in the attached drawings. Accordingly, the directional terms used are illustrative and not limiting of the invention. In order to demonstrate the characteristics of this embodiment, only the structures related to this embodiment are shown, and the other structures are omitted.

The so-called lens in the present invention refers to an element that is made of a partially or fully penetrable material and has diopter (power), and is usually composed of glass or plastic. It can include general lenses, prisms, apertures, cylindrical lenses, biconical lenses, cylindrical array lenses, wedge lenses, wedges, or a combination of the aforementioned elements.

When the lens is used in a projection system, the magnification side refers to the side on the optical path close to the imaging surface (such as a screen), and the reduction side refers to the side on the optical path close to the light source or light valve.

The object side (or image side) of a lens has a convex surface (or concave surface) located in a certain area ) means that the area is more "outwardly convex" (or "inwardly concave") in the direction parallel to the optical axis than the area immediately outside the area in the radial direction.

FIG. 1 is a schematic diagram of a projection device according to an embodiment of the present invention. Referring to FIG. 1 , the projection device 100 of this embodiment can be applied to a car lamp and includes an image source 120 and an optical lens 10 . The image source 120 includes light sources such as μ-LED, laser or LED. In addition, in this embodiment, a lens 130 (or a reflector) can be provided on the reduction side of the optical lens 10, and the image beam I can be deflected by the lens 130 (or a reflector) before entering the optical lens 10 to obtain a turning point. The optical path is used to reduce the overall space occupied by the projection device 100. In one embodiment, the image source 120 can be disposed on the reduction side of the optical lens 10 to directly face the optical lens 10, and the image beam I directly enters the optical lens 10 from the image source 120.

FIG. 2 is an optical structural diagram of the optical lens according to the first embodiment of the present invention. Please refer to Figure 2. In this embodiment, the optical lens 10a is disposed between the lens magnification side OS and the lens reduction side IS. The optical lens 10a has a lens barrel (not shown), and the lens barrel moves from the magnification side OS to the reduction side. IS arranges the lens L1, the lens L2, the aperture 14, the lens L3 and the lens L4 in order. In addition, the image source 120 is located at the position corresponding to the reduction side IS. In this embodiment, the optical lens 10a is essentially composed of four lenses, and the refractive powers of the lenses L1 to L4 on the optical axis 12 are positive, negative, positive, and positive respectively in order. Lens L2 and lens L3 are aspherical plastic lenses, and lens L1 and lens L4 are spherical glass lenses. In this embodiment, lens L1 and lens L2 may form a lens group G1, and lens L3 and lens L4 may form a lens group G2 with positive refractive power.

According to the design of the embodiment of the present invention, one of the refractive power value of the aspherical plastic lens L2 and the refractive power value of the aspherical plastic lens L3 is positive and the other is negative. For example, in this example, lens L2 has negative refractive power and lens L3 has positive refractive power. In other lens designs, lens L2 may have positive refractive power and lens L3 may have negative refractive power. Furthermore, according to the design of the embodiment of the present invention, the positive and negative values of the curvature radii (diopter) of the surface of the aspherical plastic lens L2 in a first direction and a second direction are the same, and the first direction and the second direction are perpendicular to each other. , and the positive and negative values of the curvature radii (diopter) of the surface of the aspheric plastic lens L3 in the first direction and the second direction are the same, but the embodiment of the present invention is not limited to this. For example, as shown in Figure 20A and Figure 20B, the first direction can be The X-axis direction and the second direction may be the Y-axis direction. The positive and negative values of the curvature radii of the lens surface shown in FIG. 20A in the X-axis direction and the Y-axis direction are the same (both are positive), and the surface of the lens shown in FIG. 20B is in The positive and negative values of the curvature radius in the X-axis direction and the Y-axis direction are the same (both are negative).

Furthermore, in each specific embodiment of the present invention, the number of lenses, the shape and optical characteristics of the lenses can be designed differently according to actual needs. The enlargement side OS of each specific embodiment of the present invention is located on the left side of each figure, and the image reduction side IS is located on the right side of each figure. The description will not be repeated.

The aperture 14 referred to in the present invention refers to an aperture stop (Aperture Stop). The aperture 14 is, for example, an independent component. However, the present invention is not limited thereto. The aperture 14 can also be integrated with other optical components. In this embodiment, the aperture 14 achieves a similar effect by using a mechanical component to block peripheral light and leave the middle part of the light transmitting, and the aforementioned so-called mechanical component may be adjustable. The so-called adjustable refers to the adjustment of the position, shape or transparency of the mechanical components. Alternatively, the aperture 14 can also be coated with an opaque light-absorbing material on the surface of the lens, leaving the central part transparent to achieve the effect of limiting the light path. When the aperture of the aperture 14 is larger, the optical lens 10a can correspond to a smaller aperture value (F-number). According to the design of the embodiment of the present invention, the aperture 14 may be disposed between the lens closest to the magnifying side of the lens and the reducing side of the lens.

A spherical lens means that the front and back surfaces of the lens are parts of the spherical surface, and the curvature of the spherical surface is fixed. The lens design parameters and appearance of the optical lens 10a are shown in Table 1 respectively. However, the information listed below is not intended to limit the present invention. Anyone with ordinary knowledge in the art can make appropriate changes to the parameters or settings after referring to the present invention, but they should still fall within the scope of the present invention. .

Table 1 records the values of the optical parameters of each lens in the optical system. The * in the surface number indicates that the surface is an aspherical surface; conversely, if there is no * in the surface number, it is a spherical surface. The units of curvature radius and spacing/thickness in Table 1 are millimeters (mm).

In Table 1, the radius of curvature (mm) refers to the radius of curvature of the corresponding surface, and the distance (mm) refers to the straight-line distance between two adjacent surfaces on the optical axis 12. For example, the distance between surfaces S1 is the distance between surface S1 and surface S2, the distance between surfaces S9 is the distance between surface S9 and surface S10, the thickness, refractive index and corresponding thickness of each lens and each optical element in the column are For Abbe number, please refer to the corresponding values of each spacing, refractive index and Abbe number in the same column. Surfaces S1 and S2 are both surfaces of lens L1. Surfaces S3 and S4 are both surfaces of the second lens L2. For parameter values such as the radius of curvature and spacing of each surface, please refer to Table 1, which will not be repeated here.

Radius of curvature refers to the reciprocal of curvature. When the radius of curvature is positive, the spherical center of the lens surface is in the direction of the 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 magnification side of the lens, and the convexity and concavity of each lens can be seen in the table above.

The aperture value of this embodiment is represented by F/# (F-number), as indicated in the above table. According to the design of the embodiment of the present invention, the aperture value (F-number) of the optical lens can be between 0.4 and 0.86, and the absolute value of the distortion of the optical lens is less than 5%. In this embodiment, the aperture value (F-number) of the optical lens 10a is 0.59, and the distortion amount is about -3%.

EFL is the effective focal length of the optical lens 10a. In this embodiment, the effective focal length EFL of the optical lens 10a is 24.4mm, and |EFL/BFL|=9.57. BFL is the back focal length of an optical lens. Wikipedia explains BFL as follows, "For thick lenses (lenses with a thickness that cannot be ignored), or systems with several lenses or mirrors (such as camera lenses or telescopes) ), the focal length is usually expressed by the effective focal length (EFL, effective focal length) to distinguish it from the commonly used parameters: ...the back focal length (BFD) or the back focal length (BFL) is the last optical surface vertex of the system to the rear Focus distance.", which is the spacing of S9 in Table 1, 2.55mm. When an optical lens is used as an imaging lens, BFL is the distance from the vertex of the optical surface closest to the zoom side of the optical lens to the rear imaging surface. At this time, the object distance of the lens is set to infinity or on the magnification side of the lens. Zero-degree parallel light is incident on the optical lens. The optical lens of the embodiment of the present invention can meet the condition of |EFL/BFL|>3.8. When this condition is met, the imaging resolution can be prevented from decreasing too much under a large aperture. Preferably, |EFL/BFL|>4.5 is better, and even better for |EFL/BFL|>5.

The full field of view FOV refers to the light collection angle of the optical surface S1 closest to the magnification side OS, that is, the full field of view measured diagonally. According to the design of the embodiment of the present invention, the full field of view angle can be greater than 25 degrees and less than 45 degrees, preferably greater than 26 degrees and less than 42 degrees, and more preferably greater than 28 degrees and less than 40 degrees. In this embodiment, the full field of view FOV of the optical lens 10a is 31.6 degrees. According to the design of the embodiment of the present invention, the total length (TTL) of the optical lens is less than 90 mm, that is, the distance from the apex of the optical surface of the optical lens closest to the lens magnification side to the rear imaging surface (image source).

According to the design of the embodiment of the present invention, the refractive index of the first aspherical plastic lens L1 and the second aspherical plastic lens L2 can be between 1.47-1.6, preferably between 1.50-1.6, and more preferably Between 1.57-1.6. The material of the aspherical plastic lens can be, for example, PMMA or PC.

上述的公式中，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是圓錐係數(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-G分別代表非球面多項式的4階項、6階項、8階項、10階項、12階項、14階項、16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。 A spherical lens means that the front and back surfaces of the lens are parts of the spherical surface, and the curvature of the spherical surface is fixed. Aspheric lenses refer to the curvature radius of at least one of the front and rear surfaces of the lens that changes with the central axis, which can be used to correct aberrations. In the following design examples of the present invention, the aspheric polynomial can be expressed by the following formula:

In the above formula, Z is the offset (sag) in the direction of the optical axis, c is the reciprocal of the radius of the osculating sphere, which is the reciprocal of the radius of curvature close to the optical axis, and k is the cone coefficient (conic). , r is the aspherical height, which is the height from the center of the lens to the edge of the lens. AG in Table 2 respectively represents the coefficient values of the 4th-order, 6th-order, 8th-order, 10th-order, 12th-order, 14th-order and 16th-order terms of the aspheric polynomial. However, the information listed below is not intended to limit the present invention. Anyone with ordinary knowledge in the art can make appropriate changes to the parameters or settings after referring to the present invention, but they should still fall within the scope of the present invention. .

14 and 15 are imaging optical simulation data diagrams of the optical lens 10a of FIG. 2 . Please refer to Figure 14. Figure 14 is a modulation transfer function (MTF) graph. The horizontal axis is the spatial frequency in cycles per millimeter (spatial frequency in cycles per millimeter), and the vertical axis is the modulus of the optical transfer function. (modulus of the OTF). FIG. 15 is a distortion diagram of the optical lens 10a of FIG. 2 . Since the graphics shown in Figures 14 and 15 are within the required range, it can be verified that the optical lens 10a of this embodiment can achieve good imaging effects.

FIG. 3 is an optical structural diagram of the optical lens 10b according to the second embodiment of the present invention. In this embodiment, the lens L1, the lens L2, the aperture 14, the lens L3, the lens L4 and the lens L5 are arranged in order from the magnification side OS to the reduction side IS, and the diopters of the lenses L1 to L5 on the optical axis 12 are in order. They are positive, negative, positive, positive and negative respectively. Lens L2 and lens L3 are aspheric plastic lenses, and lens L1, lens L4 and lens L5 are spherical glass lenses. Lens L4 and lens L5 can be formed into A cemented lens. In this embodiment, the full field of view FOV of the optical lens 10b is 31.6 degrees, the aperture value (F-number) is 0.59, the effective focal length EFL of the optical lens 10b is 24.4mm, and |EFL/BFL|=8.87. In this embodiment, lens L1 and lens L2 may form a lens group G1, and lens L3, lens L4 and lens L5 may form a lens group G2 with positive refractive power. The design parameters of the lens and its surrounding components of the optical lens 10b are shown in Table 3, and the cone coefficients and aspherical coefficients of each aspheric surface are shown in Table 4.

FIG. 4 is an optical structural diagram of an optical lens 10c according to the third embodiment of the present invention. In this embodiment, the optical lens 10c arranges the lens L1, the lens L2, the aperture 14, the lens L3, and the lens L4 in order from the magnification side OS to the reduction side IS, and the diopters of the lenses L1 to L4 on the optical axis 12 are in order. They are positive, negative, positive and positive respectively. Lens L2 and lens L3 are aspherical plastic lenses, and lens L1 and lens L4 are spherical glass lenses. In this embodiment, lens L1 and lens L2 may form a lens group G1, and lens L3 and lens L4 may form a lens group G2 with positive refractive power. In this embodiment, the full field of view FOV of the optical lens 10c is 31.8 degrees, the aperture value (F-number) is 0.6, the effective focal length EFL of the optical lens 10c is 24.4mm, and |EFL/BFL|=8.53. The design parameters of the lens and peripheral components of the optical lens 10c are shown in Table 5, and the cone coefficients and aspherical coefficients of each aspheric surface are shown in Table 6.

FIG. 5 is an optical structural diagram of an optical lens 10d according to the fourth embodiment of the present invention. In this embodiment, the optical lens 10d has the lens L1, the lens L2, the aperture 14, the lens L3, and the lens L4 arranged in order from the magnification side OS to the reduction side IS, and the diopters of the lenses L1 to L4 on the optical axis 12 are in order. They are positive, negative, positive and positive respectively. Lens L2 and lens L3 are aspherical plastic lenses, and lens L1 and lens L4 are spherical glass lenses. In this embodiment, lens L1 and lens L2 may form a lens group G1, and lens L3 and lens L4 may form a lens group G2 with positive refractive power. In this embodiment, the full field of view FOV of the optical lens 10d is 31.8 degrees, the aperture value (F-number) is 0.59, the effective focal length EFL of the optical lens 10d is 24.5mm, and |EFL/BFL|=10.21. The design parameters of the lens and peripheral components of the optical lens 10d are shown in Table 7, and the cone coefficients and aspherical coefficients of each aspheric surface are shown in Table 8.

FIG. 6 is an optical structural diagram of an optical lens 10e according to the fifth embodiment of the present invention. In this embodiment, the optical lens 10e has the lens L1, the lens L2, the aperture 14, the lens L3, and the lens L4 arranged in order from the magnification side OS to the reduction side IS, and the diopters of the lenses L1 to L4 on the optical axis 12 are in order. They are positive, negative, positive and positive respectively. Lens L2 and lens L3 are aspherical plastic lenses, and lens L1 and lens L4 are spherical glass lenses. In this embodiment, lens L1 and lens L2 may form a lens group G1, and lens L3 and lens L4 may form a lens group G2 with positive refractive power. In this embodiment, the full field of view FOV of the optical lens 10e is 31.6 degrees, the aperture value (F-number) is 0.59, the effective focal length EFL of the optical lens 10e is 24.5mm, and |EFL/BFL|=10.34. The design parameters of the lens and peripheral components of the optical lens 10e are shown in Table 9, and the cone coefficients and aspherical coefficients of each aspheric surface are shown in Table 10.

16 and 17 are imaging optical simulation data diagrams of the optical lens 10e of FIG. 6 . FIG. 16 is a modulation transfer function (MTF) graph of the optical lens 10e of FIG. 6 , and FIG. 17 is a distortion graph of the optical lens 10e of FIG. 6 . Since the graphics shown in FIG. 16 and FIG. 17 are both within the required range, it can be verified that the optical lens 10e of this embodiment can achieve good imaging effects.

FIG. 7 is an optical structural diagram of an optical lens 10f according to the sixth embodiment of the present invention. In this embodiment, the optical lens 10f has the lens L1, the lens L2, the aperture 14, the lens L3, and the lens L4 arranged in order from the magnification side OS to the reduction side IS, and the diopters of the lenses L1 to L4 on the optical axis 12 are in order. They are positive, negative, positive and positive respectively. Lens L1, lens L2 and lens L3 are aspherical plastic lenses, and lens L4 is a spherical glass lens. In this embodiment, lens L1 and lens L2 may form a lens group G1, and lens L3 and lens L4 may form a lens group G2 with positive refractive power. In this embodiment, the full field of view FOV of the optical lens 10f is 32 degrees, the aperture value (F-number) is 0.6, the effective focal length EFL of the optical lens 10f is 24.5mm, and |EFL/BFL|=9.01. The design parameters of the lens and peripheral components of the optical lens 10f are shown in Table 11, and the cone coefficients and aspherical coefficients of each aspheric surface are shown in Table 12.

Table 11

FIG. 8 is an optical structural diagram of an optical lens 10g according to the seventh embodiment of the present invention. In this embodiment, the optical lens 10g has the lens L1, the lens L2, the aperture 14, the lens L3, and the lens L4 arranged in order from the magnification side OS to the reduction side IS, and the diopters of the lenses L1 to L4 on the optical axis 12 are in order. They are positive, negative, positive and positive respectively. Lens L2 and lens L3 are aspherical plastic lenses, and lens L1 and lens L4 are spherical glass lenses. In this embodiment, lens L1 and lens L2 may form a lens group G1, and lens L3 and lens L4 may form a lens group G2 with positive refractive power. In this embodiment, the full field of view FOV of the optical lens 10g is 31.8 degrees, the aperture value (F-number) is 0.6, and the optical lens The effective focal length EFL of the 10g head is 24.5mm, |EFL/BFL|=10.04. The design parameters of the lens and peripheral components of the 10g optical lens are shown in Table 13, and the cone coefficients and aspherical coefficients of each aspheric surface are shown in Table 14.

FIG. 9 is an optical structural diagram of an optical lens 10h according to the eighth embodiment of the present invention. In this embodiment, the optical lens 10h has lenses L1, L2, and L3 sequentially arranged from the magnification side OS to the reduction side IS, and the refractive powers of the lenses L1 to L3 on the optical axis 12 are respectively positive, negative, and negative. just. Lens L1 and lens L2 are aspherical plastic lenses, and lens L3 is a spherical glass lens. at In this embodiment, the aperture 14 is located on the surface S1 of the lens L1. In this embodiment, the full field of view FOV of the optical lens 10h is 35.2 degrees, the aperture value (F-number) is 0.65, the effective focal length EFL of the optical lens 10h is 21.9mm, and |EFL/BFL|=5.43. The design parameters of the lens and peripheral components of the optical lens 10h are shown in Table 15, and the cone coefficients and aspherical coefficients of each aspheric surface are shown in Table 16.

FIG. 10 is an optical structural diagram of an optical lens 10i according to the ninth embodiment of the present invention. In this embodiment, the optical lens 10i has lenses L1, L2, L3, L4 and L5 arranged in order from the magnification side OS to the reduction side IS, and the diopters of the lenses L1 to L5 on the optical axis 12 are in order. They are positive, negative, positive, negative and positive respectively. Lens L1 and lens L2 are aspherical plastic lenses. And the lens L3, the lens L4 and the lens L5 are spherical glass lenses, and the lens L4 and the lens L5 can form a cemented lens. In this embodiment, the aperture 14 is located on the surface S4 of the lens L2. In this embodiment, the full field of view FOV of the optical lens 10i is 31.2 degrees, the aperture value (F-number) is 0.59, the effective focal length EFL of the optical lens 10i is 24mm, and |EFL/BFL|=4.6. In this embodiment, lens L1 and lens L2 may form a lens group G1, and lens L3, lens L4 and lens L5 may form a lens group G2 with positive refractive power. The design parameters of the lens and peripheral components of the optical lens 10i are shown in Table 17, and the cone coefficients and aspheric coefficients of each aspheric surface are shown in Table 18.

FIG. 11 is an optical structural diagram of an optical lens 10j according to the tenth embodiment of the present invention. In this embodiment, the optical lens 10j has lenses L1, L2, L3 and L4 sequentially arranged from the magnification side OS to the reduction side IS, and the refractive powers of the lenses L1 to L4 on the optical axis 12 are respectively positive in order. , negative, positive, positive. Lens L1 and lens L2 are aspherical plastic lenses, and lens L3 and lens L4 are spherical glass lenses. In this embodiment, the lens L1 constitutes the lens group G1, and the lens L2, the lens L3 and the lens L4 may constitute the lens group G2 with positive refractive power. In this embodiment, the aperture 14 is located on the surface S3 of the lens L2. In this embodiment, the full field of view FOV of the optical lens 10j is 30.4 degrees, the aperture value (F-number) is 0.61, the effective focal length EFL of the optical lens 10j is 24mm, and |EFL/BFL|=4.54. The design parameters of the lens and peripheral components of the optical lens 10i are shown in Table 19, and the cone coefficients and aspheric coefficients of each aspheric surface are shown in Table 20.

FIG. 12 is an optical structural diagram of an optical lens 10k according to the eleventh embodiment of the present invention. In this embodiment, the optical lens 10k has lenses L1, L2, L3, and L4 sequentially arranged from the magnification side OS to the reduction side IS, and the refractive powers of the lenses L1 to L4 on the optical axis 12 are respectively positive in order. , negative, positive, positive. Lens L1 and lens L2 are aspherical plastic lenses, and lens L3 and lens L4 are spherical glass lenses. In this embodiment, the lens L1 constitutes the lens group G1, and the lens L2, the lens L3 and the lens L4 may constitute the lens group G2 with positive refractive power. In this embodiment, the aperture 14 is located on the surface S3 of the lens L2. In this embodiment, the full field of view FOV of the optical lens 10k is 31.8 degrees, the aperture value (F-number) is 0.85, the effective focal length EFL of the optical lens 10k is 33mm, and |EFL/BFL|=5.53. The design parameters of the lens and its surrounding components of the optical lens 10k are shown in Table 21, and the cone coefficients and aspherical coefficients of each aspheric surface are shown in Table 22.

18 and 19 are imaging optical simulation data diagrams of the optical lens 10k of FIG. 12 . FIG. 18 is a modulation transfer function (MTF) graph of the optical lens 10k of FIG. 12 , and FIG. 19 is a distortion graph of the optical lens 10k of FIG. 12 . Since the graphics shown in FIG. 18 and FIG. 19 are both within the required range, it can be verified that the optical lens 10k of this embodiment can achieve good imaging effects.

FIG. 13 is an optical structural diagram of the optical lens 101 according to the twelfth embodiment of the present invention. In this embodiment, the optical lens 10l has the lens L1, the lens L2, the aperture 14, the lens L3, the lens L4 and the lens L5 arranged in order from the magnification side OS to the reduction side IS, and the distance between the lens L1 to the lens L5 on the optical axis 12 is Diopters are positive, negative, positive, positive, and negative in order. Lens L2 and lens L3 are aspherical plastic lenses, and lens L1, lens L4 and lens L5 are spherical glass lenses. Lens L4 and lens L5 can form a cemented lens. In this embodiment, the full field of view FOV of the optical lens 101 is 31.8 degrees, the aperture value (F-number) is 0.6, the effective focal length EFL of the optical lens 101 is 24.2mm, and |EFL/BFL|=6.95. In this embodiment, lens L1 and lens L2 may form a lens group G1, and lens L3, lens L4 and lens L5 may form a lens group G2 with positive refractive power. The design parameters of the lens and peripheral components of the optical lens 10l are shown in Table 23, and the cone coefficients and aspherical coefficients of each aspheric surface are shown in Table 24.

Embodiments of the present invention can provide lower manufacturing costs while still maintaining good quality by making at least two of the first lens L1, the second lens L2 and the third lens L3 made of plastic and aspherical lenses. Image quality, in addition, by making the optical lens essentially consist of 3 to 5 lenses, low manufacturing costs can also be achieved. Moreover, in the embodiment of the present invention, the lens close to the reduction side is made of glass, so that it can have a wider operating temperature range. To sum up, the optical lens of the present invention has at least one of the following advantages: through the design of the embodiment of the present invention, it can provide an illumination range that meets the requirements of traffic regulations, high resolution, low distortion, miniaturization, etc. , and can provide lenses with lower manufacturing costs and better imaging quality for automotive headlights. design.

Although the present invention has been disclosed above through embodiments, they are not intended to limit the present invention. Anyone with ordinary knowledge in the technical field may make some modifications and modifications without departing from the spirit and scope of the present invention. Therefore, The protection scope of the present invention shall be determined by the appended patent application scope.

10a optical lens 12 optical axis 14 aperture 120 image sources G1;G2 lens group L1-L4 lens S1-S10 Surface OS magnified side IS zoom side

Claims (10)

An optical lens, applied to car lights, including: three lenses closest to the magnification side of the lens, in order: a first lens with a positive diopter value, a second lens with a negative diopter value, and a third lens. And the lens includes at most 5 lenses; the three lenses include at least two aspherical lenses, and the diopter value of the two aspherical lenses is positive and the other is negative; the diopter value is positive and non-positive. The positive and negative values of the radii of curvature of the spherical lens in a first direction and a second direction are the same, and the first direction and the second direction are perpendicular to each other; the lens closest to the reduction side of the lens and having diopter is a spherical glass lens; And the field of view of the lens is greater than 25 degrees and less than 45 degrees. The optical lens as described in claim 1, wherein the optical lens meets one of the following conditions: (1) an aperture is provided between the magnifying side of the lens and the third lens, (2) an aperture is provided on the reducing side of the lens Or a reflector. An optical lens includes: a first lens group, an aperture and a second lens group in sequence from the lens magnification side to the lens reduction side; the first lens group includes 1~2 lenses with diopter, the 1~ The 2 lenses with refractive power include a first aspherical lens; the second lens group includes 2 to 3 lenses with refractive power, and the 2 to 3 lenses with refractive power include a second aspherical lens and a spherical glass lens , and the spherical glass lens is the lens closest to the reduction side of the lens and has diopter; the diopter value of the first aspherical lens and the second aspherical lens, one is positive and the other is negative; the diopter value A positive aspherical lens has the same positive and negative values of the radius of curvature in a first direction and a second direction, and the first direction and the second direction are perpendicular to each other; the lens meets the following conditions: 25 degree lens. The optical lens as described in claim 1 or 3, wherein the optical lens meets one of the following conditions: (1) the absolute value of the distortion of the lens is less than 5%, (2) the aperture value (F-number) of the lens is between Between 0.4 and 0.86. The optical lens as described in claim 3, wherein the optical lens meets one of the following conditions: (1) the first aspherical lens and the second aspherical lens are made of PMMA or PC, (2) the first aspherical lens The refractive index of the spherical lens and the second aspherical lens is between 1.47-1.6, (3) the radius of curvature of the surface of the first aspherical lens facing the magnification side of the lens is positive, (4) the first aspherical lens has a positive refractive index. The spherical lens and the second aspherical lens have the same radius of curvature in the first direction and the second direction. The optical lens according to claim 1 or 3, wherein the optical lens includes a cemented lens. The optical lens as described in claim 1 or 3, wherein in the direction from the magnifying side of the lens to the reducing side of the lens, the optical lens satisfies one of the following conditions: (1) It is biconvex or aspherical in order from this direction. , aspheric, crescent lens, (2) from this direction, the order is biconvex, aspheric, aspheric, biconvex, biconcave lens, (3) from this direction, the order is crescent, aspheric, aspheric, Crescent lens, (4) from this direction are aspheric, aspheric, aspheric, crescent lens, (5) from this direction are aspheric, aspheric, biconvex, crescent, crescent lens , (6) From this direction, the order is aspherical, aspherical, biconvex, and crescent lenses. (7) From this direction, the order is aspherical, aspherical, and plano-convex lenses. The optical lens as described in claim 1 or 3, wherein in the direction from the magnifying side of the lens to the reducing side of the lens, the optical lens satisfies one of the following conditions: (1) The diopter of the lens from this direction is positive in sequence. , negative, positive, positive, (2) the diopter of the lens from this direction is positive, negative, positive, positive, negative in order, (3) the diopter of the lens from this direction is positive, negative, positive, negative in order , positive, (4) the diopters of the lens from this direction are positive, negative, and positive respectively. The optical lens as described in claim 1 or 3, wherein the total length (TTL) of the optical lens is less than 90mm. The optical lens as described in claim 1 or 3, wherein the optical lens meets one of the following conditions: (1) the aspheric lens is made of plastic, (2) the lens is a glass-plastic hybrid structure.

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