Optical lens assembly

Abstract

The present application discloses an optical lens group for generating multiple light beams from multiple near-infrared lights emitted by a multi-light-source structured light generating unit via the optical lens group. The direction toward the multi-light-source structured light generating unit is an entrance light side, and the opposite side is an exit light side. The optical lens group sequentially includes first, second, third, and fourth lenses along an optical axis from the exit light side to the entrance light side. The first lens is the fourth lens from the entrance light side to the exit light side. The second lens is the third lens from the entrance light side to the exit light side. The third lens is the second lens from the entrance light side to the exit light side. The fourth lens is the first lens from the entrance light side to the exit light side. The number of lens pieces of the optical lens group is at most five, and satisfies LCR / T2≦2.500. The optical lens group can greatly reduce the lens cost of the transmitting end of the 3D sensing technology and reduce the manufacturing bottleneck.

Description

[0001] This invention patent application is a divisional application. The original application number is 201711071718.X, the application date is November 3, 2017, and the invention title is: Optical Lens Assembly. Technical Field

[0002] This invention relates to the field of optical lenses, and more particularly to optical lens assemblies. Background Technology

[0003] The specifications of portable electronic products are changing rapidly, and their key components - optical lens groups - are also becoming more diversified. They are not only used for photography and video recording, but also for three-dimensional (3D) sensing technology as technology advances.

[0004] Current 3D sensing technology uses multiple near-infrared light emitting units, each using multiple collimating lenses to generate multiple light beams that are projected onto the environment in front. A camera then captures the image of the environment projected by the near-infrared light to create a three-dimensional representation of the surrounding space. More specifically, a single near-infrared light emitted by one set of near-infrared light emitting units is used to generate a single light beam through a corresponding set of collimating lenses. Current 3D sensing technology uses multiple collimating lenses to detect a large area of ​​the environment. However, the manufacturing process for this combination of multiple collimating lenses and multiple near-infrared light emitting units is expensive and has poor yield. For example, because each near-infrared light emitting unit is quite small, the corresponding collimating lens is formed using a wafer-level optical lens process, which has low yield and high manufacturing costs.

[0005] Therefore, designing lenses that can be combined with multiple near-infrared light emitting units to generate multiple beams with different angles, while simultaneously meeting specifications such as small size, high production yield, and thermal stability, has always been the direction of efforts for those skilled in the art. Summary of the Invention

[0006] This invention provides an optical lens assembly that enables a multi-source structured light generation unit to generate multiple beams with different angles through this optical lens assembly, which can significantly reduce the lens cost of the transmitter in 3D sensing technology and reduce manufacturing bottlenecks.

[0007] An embodiment of the present invention provides an optical lens assembly for generating multiple beams from multiple near-infrared lights emitted by a multi-source structured light generating unit. The direction towards the multi-source structured light generating unit is an incident light side, and the opposite direction is an emitting light side. The optical lens assembly sequentially includes a first lens, a second lens, a third lens, and a fourth lens along an optical axis from the emitting light side to the incident light side. Each of the first, second, third, and fourth lenses includes an emitting surface facing the emitting light side and an incident light surface facing the incident light side. The first lens is the fourth lens from the incident light side to the emitting light side. The second lens is the third lens from the incident light side to the emitting light side. The third lens is the second lens from the incident light side to the emitting light side. The fourth lens is the first lens from the incident light side to the emitting light side. The optical lens assembly has a maximum of five lenses and satisfies LCR / T2≦2.500.

[0008] Another embodiment of the present invention provides an optical lens assembly for generating multiple beams from multiple near-infrared lights emitted by a multi-source structured light generating unit. The direction towards the multi-source structured light generating unit is an incident light side, and the opposite direction is an exit light side. The optical lens assembly sequentially includes a first lens, a second lens, a third lens, and a fourth lens along an optical axis from the exit light side to the incident light side. Each of the first, second, third, and fourth lenses includes an exit light surface facing the exit light side and an incident light surface facing the incident light side. The first lens is the fourth lens from the incident light side to the exit light side. The second lens is the third lens from the incident light side to the exit light side. The third lens is the second lens from the incident light side to the exit light side. The fourth lens is the first lens from the incident light side to the exit light side. The optical lens assembly has a maximum of five lenses and satisfies HFOV ≤ 20°.

[0009] Another embodiment of the present invention provides an optical lens assembly for generating multiple beams from multiple near-infrared lights emitted by a multi-source structured light generating unit. The direction towards the multi-source structured light generating unit is an incident light side, and the opposite direction is an exit light side. The optical lens assembly sequentially includes a first lens, a second lens, a third lens, and a fourth lens along an optical axis from the exit light side to the incident light side. Each of the first, second, third, and fourth lenses includes an exit light surface facing the exit light side and an incident light surface facing the incident light side. The first lens is the fourth lens from the incident light side to the exit light side. The second lens is the third lens from the incident light side to the exit light side. The third lens is the second lens from the incident light side to the exit light side. The fourth lens is the first lens from the incident light side to the exit light side. The optical lens assembly has a maximum of five lenses, satisfying 2.550 ≤ (n1 + n2 + n3 + n4) - 4 ≤ 3.500.

[0010] Another embodiment of the present invention provides an optical lens assembly for generating multiple beams from multiple near-infrared lights emitted by a multi-source structured light generating unit. The direction towards the multi-source structured light generating unit is an incident light side, and the opposite direction is an exit light side. The optical lens assembly sequentially includes a first lens, a second lens, a third lens, and a fourth lens along an optical axis from the exit light side to the incident light side. Each of the first, second, third, and fourth lenses includes an exit light surface facing the exit light side and an incident light surface facing the incident light side. The first lens is the fourth lens from the incident light side to the exit light side. The second lens is the third lens from the incident light side to the exit light side. The third lens is the second lens from the incident light side to the exit light side. The fourth lens is the first lens from the incident light side to the exit light side. The optical lens assembly has a maximum of five lenses and satisfies TL / ALT ≤ 1.900.

[0011] Another embodiment of the present invention provides an optical lens assembly for generating multiple beams from multiple near-infrared lights emitted by a multi-source structured light generating unit. The direction towards the multi-source structured light generating unit is an incident light side, and the opposite direction is an exit light side. The optical lens assembly sequentially includes a first lens, a second lens, a third lens, and a fourth lens along an optical axis from the exit light side to the incident light side. Each of the first, second, third, and fourth lenses includes an exit light surface facing the exit light side and an incident light surface facing the incident light side. The first lens is the fourth lens from the incident light side to the exit light side. The second lens is the third lens from the incident light side to the exit light side. The third lens is the second lens from the incident light side to the exit light side. The fourth lens is the first lens from the incident light side to the exit light side. The optical lens assembly has a maximum of five lenses and satisfies TTL / (T2+T3)≦7.400.

[0012] Another embodiment of the present invention provides an optical lens assembly for generating multiple beams from multiple near-infrared lights emitted by a multi-source structured light generating unit. The direction towards the multi-source structured light generating unit is an incident light side, and the opposite direction is an exit light side. The optical lens assembly sequentially includes a first lens, a second lens, a third lens, and a fourth lens along an optical axis from the exit light side to the incident light side. Each of the first, second, third, and fourth lenses includes an exit light surface facing the exit light side and an incident light surface facing the incident light side. The first lens is the fourth lens from the incident light side to the exit light side. The second lens is the third lens from the incident light side to the exit light side. The third lens is the second lens from the incident light side to the exit light side. The fourth lens is the first lens from the incident light side to the exit light side. The optical lens assembly has a maximum of five lenses, satisfying (AAG+BFL) / (T2+T4)≦1.800.

[0013] Another embodiment of the present invention provides an optical lens assembly for generating multiple beams from multiple near-infrared lights emitted by a multi-source structured light generating unit. The direction towards the multi-source structured light generating unit is an incident light side, and the opposite direction is an exit light side. The optical lens assembly sequentially includes a first lens, a second lens, a third lens, and a fourth lens along an optical axis from the exit light side to the incident light side. Each of the first, second, third, and fourth lenses includes an exit light surface facing the exit light side and an incident light surface facing the incident light side. The first lens is the fourth lens from the incident light side to the exit light side. The second lens is the third lens from the incident light side to the exit light side. The third lens is the second lens from the incident light side to the exit light side. The fourth lens is the first lens from the incident light side to the exit light side. The optical lens assembly has a maximum of five lenses, satisfying (G23+G34+T4) / (T2+T3)≦3.800.

[0014] This optical lens group better meets one of the following conditions:

[0015] (T1+G23) / (G12+G34)≦3.500

[0016] (G34+T4) / (T1+G12)≦2.500,

[0017] V1+V2+V3+V4≦141,

[0018] Wherein, V1 is the Abbe coefficient of the first lens, V2 is the Abbe coefficient of the second lens, V3 is the Abbe coefficient of the third lens, and V4 is the Abbe coefficient of the fourth lens; n1 is the refractive index of the first lens, n2 is the refractive index of the second lens, n3 is the refractive index of the third lens, and n4 is the refractive index of the fourth lens; T1 is the thickness of the first lens on the optical axis, T2 is the thickness of the second lens on the optical axis, T3 is the thickness of the third lens on the optical axis, and T4 is the thickness of the fourth lens on the optical axis; G12 is the air gap between the first lens and the second lens on the optical axis, G23 is the air gap between the second lens and the third lens on the optical axis, and G34 is the air gap between the third lens and the fourth lens on the optical axis; LCR is the radius of the smallest circumcircle of the light-emitting surface of the multi-source structured light generation unit. AAG is the sum of the air gaps on the optical axis between all lenses with refractive indices in the optical lens group. BFL is the distance on the optical axis from the incident surface of the fourth lens to the structured light generating unit of the multi-source light source. TTL is the distance on the optical axis from the emitting surface of the first lens to the structured light generating unit of the multi-source light source, counted from the emitting side. LCR is the radius of the smallest circumcircle of the emitting surface of the structured light generating unit of the multi-source light source. EFL is the system focal length of the optical lens group. ALT is the sum of the thicknesses on the optical axis of all lenses with refractive indices in the optical lens group. TL is the distance on the optical axis from the emitting surface of the first lens to the incident surface of the fourth lens. HFOV is the half field of view of the optical lens group.

[0019] Based on the above, the beneficial effect of the optical lens group of the embodiment of the present invention is that by arranging four lenses with refractive power between the light-incident side and the light-outcident side to correspond to the structured light generation unit of multiple light sources, the lens cost of the transmitter of 3D sensing technology can be greatly reduced and the manufacturing bottleneck can be reduced. Attached Figure Description

[0020] Figure 1A This is a schematic diagram illustrating the application of the optical lens group of the present invention to a 3D sensing transmitter lens.

[0021] Figure 1B yes Figure 1A A front view of an embodiment of a multi-source structured light generating unit.

[0022] Figure 2 This is a schematic diagram illustrating the surface structure of a lens.

[0023] Figure 3 It is a schematic diagram illustrating the concave and convex structure of a lens and the focal point of light rays.

[0024] Figure 4 This is a schematic diagram illustrating the surface structure of a lens in Example 1.

[0025] Figure 5 This is a schematic diagram illustrating the surface structure of a lens in Example 2.

[0026] Figure 6 This is a schematic diagram illustrating the surface structure of a lens in Example 3.

[0027] Figure 7 This is a schematic diagram of the optical lens assembly according to the first embodiment of the present invention.

[0028] Figures 8A to 8D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the first embodiment.

[0029] Figure 9 This is a detailed optical data table diagram of the optical lens group according to the first embodiment of the present invention.

[0030] Figure 10 This is a table of aspherical parameters of the optical lens group according to the first embodiment of the present invention.

[0031] Figure 11 This is a schematic diagram of the optical lens assembly according to the second embodiment of the present invention.

[0032] Figures 12A to 12D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the second embodiment.

[0033] Figure 13 This is a detailed optical data table diagram of the optical lens group according to the second embodiment of the present invention.

[0034] Figure 14 This is a table of aspherical parameters of the optical lens group according to the second embodiment of the present invention.

[0035] Figure 15 This is a schematic diagram of the optical lens assembly according to the third embodiment of the present invention.

[0036] Figures 16A to 16D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the third embodiment.

[0037] Figure 17 This is a detailed optical data table diagram of the optical lens group according to the third embodiment of the present invention.

[0038] Figure 18 This is a table of aspherical parameters of the optical lens group according to the third embodiment of the present invention.

[0039] Figure 19 This is a schematic diagram of the optical lens assembly according to the fourth embodiment of the present invention.

[0040] Figures 20A to 20DThis is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the fourth embodiment.

[0041] Figure 21 This is a detailed optical data table diagram of the optical lens group according to the fourth embodiment of the present invention.

[0042] Figure 22 This is a table of aspherical parameters of the optical lens group according to the fourth embodiment of the present invention.

[0043] Figure 23 This is a schematic diagram of the optical lens assembly according to the fifth embodiment of the present invention.

[0044] Figures 24A to 24D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the fifth embodiment.

[0045] Figure 25 This is a detailed optical data table diagram of the optical lens group according to the fifth embodiment of the present invention.

[0046] Figure 26 This is a table of aspherical parameters of the optical lens group according to the fifth embodiment of the present invention.

[0047] Figure 27 This is a schematic diagram of the optical lens assembly according to the sixth embodiment of the present invention.

[0048] Figures 28A to 28D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the sixth embodiment.

[0049] Figure 29 This is a detailed optical data table diagram of the optical lens group according to the sixth embodiment of the present invention.

[0050] Figure 30 This is a table of aspherical parameters of the optical lens group according to the sixth embodiment of the present invention.

[0051] Figure 31 This is a schematic diagram of the optical lens assembly according to the seventh embodiment of the present invention.

[0052] Figures 32A to 32D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the seventh embodiment.

[0053] Figure 33 This is a detailed optical data table diagram of the optical lens group according to the seventh embodiment of the present invention.

[0054] Figure 34 This is a table of aspherical parameters of the optical lens group according to the seventh embodiment of the present invention.

[0055] Figure 35 This is a schematic diagram of the optical lens assembly of the eighth embodiment of the present invention.

[0056] Figures 36A to 36D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the eighth embodiment.

[0057] Figure 37 This is a detailed optical data table diagram of the optical lens group according to the eighth embodiment of the present invention.

[0058] Figure 38 This is a table of aspherical parameters of the optical lens group according to the eighth embodiment of the present invention.

[0059] Figure 39 This is a schematic diagram of the optical lens assembly of the ninth embodiment of the present invention.

[0060] Figures 40A to 40D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the ninth embodiment.

[0061] Figure 41 This is a detailed optical data table diagram of the optical lens group according to the ninth embodiment of the present invention.

[0062] Figure 42 This is a table of aspherical parameters of the optical lens group according to the ninth embodiment of the present invention.

[0063] Figure 43 This is a schematic diagram of the optical lens assembly according to the tenth embodiment of the present invention.

[0064] Figures 44A to 44D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the tenth embodiment.

[0065] Figure 45 This is a detailed optical data table diagram of the optical lens group according to the tenth embodiment of the present invention.

[0066] Figure 46 This is a table of aspherical parameters of the optical lens group according to the tenth embodiment of the present invention.

[0067] Figure 47 This is a schematic diagram of the optical lens assembly according to the eleventh embodiment of the present invention.

[0068] Figures 48A to 48D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the eleventh embodiment.

[0069] Figure 49 This is a detailed optical data table diagram of the optical lens group according to the eleventh embodiment of the present invention.

[0070] Figure 50 This is a table of aspherical parameters of the optical lens group according to the eleventh embodiment of the present invention.

[0071] Figure 51 This is a schematic diagram of the optical lens assembly according to the twelfth embodiment of the present invention.

[0072] Figures 52A to 52D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the twelfth embodiment.

[0073] Figure 53 This is a detailed optical data table diagram of the optical lens assembly according to the twelfth embodiment of the present invention.

[0074] Figure 54 This is a table of aspherical parameters of the optical lens group according to the twelfth embodiment of the present invention.

[0075] Figure 55 This is a schematic diagram of the optical lens assembly according to the thirteenth embodiment of the present invention.

[0076] Figures 56A to 56D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the thirteenth embodiment.

[0077] Figure 57 This is a detailed optical data table diagram of the optical lens group according to the thirteenth embodiment of the present invention.

[0078] Figure 58 This is a table of aspherical parameters of the optical lens group according to the thirteenth embodiment of the present invention.

[0079] Figure 59 This is a schematic diagram of the optical lens assembly according to the fourteenth embodiment of the present invention.

[0080] Figures 60A to 60D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the fourteenth embodiment.

[0081] Figure 61 This is a detailed optical data table diagram of the optical lens group according to the fourteenth embodiment of the present invention.

[0082] Figure 62 This is a table of aspherical parameters of the optical lens group according to the fourteenth embodiment of the present invention.

[0083] Figure 63 This is a schematic diagram of the optical lens assembly according to the fifteenth embodiment of the present invention.

[0084] Figures 64A to 64D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the fifteenth embodiment.

[0085] Figure 65 This is a detailed optical data table diagram of the optical lens group according to the fifteenth embodiment of the present invention.

[0086] Figure 66 This is a table of aspherical parameters of the optical lens group according to the fifteenth embodiment of the present invention.

[0087] Figure 67 This is a schematic diagram of the optical lens assembly according to the sixteenth embodiment of the present invention.

[0088] Figures 68A to 68D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the sixteenth embodiment.

[0089] Figure 69 This is a detailed optical data table diagram of the optical lens group according to the sixteenth embodiment of the present invention.

[0090] Figure 70 This is a table of aspherical parameters of the optical lens group according to the sixteenth embodiment of the present invention.

[0091] Figure 71 This is a schematic diagram of the optical lens assembly according to the seventeenth embodiment of the present invention.

[0092] Figures 72A to 72D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the seventeenth embodiment.

[0093] Figure 73 This is a detailed optical data table diagram of the optical lens group according to the seventeenth embodiment of the present invention.

[0094] Figure 74 This is a table of aspherical parameters of the optical lens group according to the seventeenth embodiment of the present invention.

[0095] Figure 75 as well as Figure 76 This is a numerical table diagram showing the important parameters and their relationships of the optical lens group in the first to sixth embodiments of the present invention.

[0096] Figure 77 as well as Figure 78 These are numerical tables showing the important parameters and their relationships of the optical lens group in the seventh to twelfth embodiments of the present invention.

[0097] Figure 79 as well as Figure 80 This is a numerical table diagram showing the important parameters and their relationships of the optical lens group in the thirteenth to seventeenth embodiments of the present invention. Detailed Implementation

[0098] Explanation of symbols in the attached diagram: 10: Optical lens group; 15: Structured light generation unit with multiple light sources; 15a: Near-infrared light source; 100a: Light-emitting surface; 2: Aperture; 3: First lens; 4: Second lens; 5: Third lens; 6: Fourth lens; 7: Fifth lens; 31, 41, 51, 61, 71: Light-emitting surfaces; 311, 313, 321, 323, 411, 413, 421, 423, 511, 513, 521, 523, 611, 613, 62 1, 623, 711, 713: Convex surface; 322, 324, 412, 422, 424, 512, 514, 522, 524, 612, 614, 622, 624, 722, 724: Concave surface; 32, 42, 52, 62, 72: Incident surface; I: Optical axis; A: Region near the optical axis; C: Region near the circumference; CF: Principal ray of near-infrared light; D: Normal direction; E: Extension; Lc: Principal ray; Lm: Peripheral ray; M, R: Point.

[0099] Please refer to Figure 1A The light direction of the three-dimensional (3D) sensing transmitter lens 20 is that multiple near-infrared lights are emitted by the multi-source structured light generation unit 15, and multiple beams a, b, and c are generated by the optical lens group 10 of this embodiment of the invention to detect the environment in front of the lens. The beams a, b, and c are not limited to any particular form; their directions are described here as dashed lines. The number of beams a, b, and c is not limited to three; they can be any number other than three or one. Figure 1A The diagram uses light beams a, b, and c to represent the beams. Please refer to [the diagram / reference]. Figure 1B In one embodiment, the multi-source structured light generating unit 15 includes a plurality of near-infrared light sources 15a arranged in an array. In other embodiments, these near-infrared light sources 15a may be arranged in a ring or other arrangements, and the present invention is not limited thereto. The near-infrared light sources 15a may be infrared laser light sources. The emitting surfaces of these near-infrared light sources 15a form the emitting surface 100a of the multi-source structured light generating unit 15.

[0100] The criteria for determining the optical specifications of the embodiments of the present invention described below are based on the assumption that the reverse tracking of the light direction is a parallel imaging light ray that passes through the optical lens group 10 from the light-emitting side to the light-emitting surface 100a of the multi-source structured light generation unit 15 for focusing and imaging.

[0101] The statement in this specification that "a lens has a positive refractive index (or a negative refractive index)" means that the lens has a positive (or negative) refractive index on the optical axis calculated using Gaussian optics theory. The incident and exit surfaces are defined as the areas through which the imaging rays pass, including the principal ray (Lc) and the marginal ray (Lm), such as... Figure 2 As shown, I is the optical axis, and this lens is radially symmetrical about this optical axis I. The area through which light passes along the optical axis is the region near the optical axis, A, and the area through which peripheral light passes is the region near the circumference, C. Furthermore, the lens includes an extension E (i.e., the radially outward region from the region near the circumference, C) for mounting the lens within an optical imaging lens. Ideally, the imaging light should not pass through this extension E, but the structure and shape of the extension E are not limited to this. For the sake of simplicity, some extensions are omitted in the following embodiments. More specifically, the method for determining the extent of the surface shape or the region near the optical axis, the region near the circumference, or multiple regions is as follows:

[0102] 1. Please refer to Figure 2 This is a radial cross-sectional view of a lens. Viewed in this cross-sectional view, when determining the extent of the aforementioned region, a center point is defined as the intersection of the lens surface and the optical axis, and a transition point is a point on the lens surface through which a tangent is perpendicular to the optical axis. If there are multiple transition points radially outward, they are sequentially designated as the first transition point, the second transition point, and the transition point furthest radially from the optical axis on the effective radius is the Nth transition point. The region between the center point and the first transition point is the area near the optical axis, and the region radially outward from the Nth transition point is the area near the circumference. Different regions can be distinguished in between based on the transition points. Furthermore, the effective radius is the perpendicular distance from the intersection of the marginal ray Lm and the lens surface to the optical axis I.

[0103] 2. For example Figure 3 As shown, the shape of this region, whether concave or convex, is determined by whether the intersection of a light ray (or its extension) parallel to the region and the optical axis is on the incident or emitting side (method for determining the focal point). For example, when light passes through this region, it will focus towards the incident side, and the focal point with the optical axis will be located on the incident side. Figure 3 If point R is the midpoint, then the region is a convex surface. Conversely, if light passes through this region, the light rays will diverge, and the focal point of their extensions and the optical axis will be on the emitting side. For example... Figure 3 Point M is the midpoint, therefore the region between the center point and the first transition point is the convex region, and the region radially upwards and outwards from the first transition point is the concave region; from Figure 3It can be seen that this transition point is the boundary between the convex and concave surfaces. Therefore, this region and the radially adjacent inner region can be defined as having different surface shapes, with this transition point as the boundary. Furthermore, the surface shape of the region near the optical axis can be determined according to the methods commonly used in this field, using the R-value (referring to the paraxial radius of curvature, usually the R-value in the lens database of optical software) to determine convexity / concavity. For the light-emitting surface, a positive R-value indicates a convex surface, and a negative R-value indicates a concave surface; for the light-receiving surface, a positive R-value indicates a concave surface, and a negative R-value indicates a convex surface. This method of determining convexity / concavity is the same as the method for determining the focal point of light.

[0104] 3. If there is no transition point on the lens surface, the area near the optical axis is defined as 0 to 50% of the effective radius, and the area near the circumference is defined as 50 to 100% of the effective radius.

[0105] Figure 4 In Example 1, the incident surface of the lens has only a first conversion point on its effective radius. Therefore, the first region is near the optical axis, and the second region is near the circumference. The R-value of the incident surface of this lens is positive, so it is determined that the region near the optical axis has a concave portion. The surface shape of the region near the circumference is different from the radially adjacent inner region. That is, the surface shape of the region near the circumference is different from that of the region near the optical axis; the region near the circumference has a convex portion.

[0106] Figure 5 In Example 2, the light-emitting surface of the lens has a first and a second transition point on its effective radius. Therefore, the first region is the area near the optical axis, and the third region is the area near the circumference. The R value of the light-emitting surface of this lens is positive, so the area near the optical axis is determined to be a convex part; the area between the first and second transition points (the second region) has a concave part, and the area near the circumference (the third region) has a convex part.

[0107] Figure 6 In Example 3, the light-emitting surface of the lens has no transition point on the effective radius. In this case, the region near the optical axis is defined as 0% to 50% of the effective radius, and the region near the circumference is defined as 50% to 100%. Since the R-value of the region near the optical axis is positive, the light-emitting surface has a convex portion in the region near the optical axis; and since there is no transition point between the region near the circumference and the region near the optical axis, the region near the circumference also has a convex portion.

[0108] Figure 7 This is a schematic diagram of the optical lens assembly according to the first embodiment of the present invention. Figures 8A to 8D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the first embodiment. Please refer to [the diagram first]. Figure 7In the optical lens group 10 of the first embodiment of the present invention, from the light-emitting side to the light-incident side along an optical axis I of the optical lens group 10, an aperture 2, a first lens 3, a second lens 4, a third lens 5, and a fourth lens 6 are sequentially included. When multiple near-infrared lights are emitted from the light-emitting surface 100a of the multi-source structured light generating unit 15 and enter the optical lens group 10, they sequentially pass through the fourth lens 6, the third lens 5, the second lens 4, the first lens 3, and the aperture 2 to generate multiple beams, which then exit the optical lens group 10. It should be noted that the light-incident side is the side facing the multi-source structured light generating unit 15, while the opposite side is the light-emitting side.

[0109] Furthermore, in order to maintain a certain optical quality in a heated environment for the optical lens group 10 of the embodiments of the present invention, the material of the first lens 3, which is closest to the aperture 2 and has a refractive index, is glass with a refractive index greater than 1.8, which helps to reduce the influence of temperature on the output beam. The second lens 4 to the fourth lens 6 are all made of plastic, but the materials of the first lens 3 to the fourth lens 7 are not limited to this.

[0110] In this embodiment, the first lens 3, the second lens 4, the third lens 5 and the fourth lens 6 of the optical lens group 10 each have an emitting surface 31, 41, 51, 61 facing the light-emitting side and allowing multiple near-infrared lights to pass through, and an incident surface 32, 42, 52, 62 facing the light-incident side and allowing multiple near-infrared lights to pass through.

[0111] The first lens 3 is the fourth lens with refractive index, measured from the incident light side to the emitting light side. The first lens 3 has positive refractive index. The emitting surface 31 of the first lens 3 has a convex portion 311 located near the optical axis I and a convex portion 313 located near the circumference. The incident surface 32 of the first lens 3 has a concave portion 322 located near the optical axis I and a concave portion 324 located near the circumference. Both the emitting surface 31 and the incident surface 32 of the first lens 3 are aspherical.

[0112] The second lens 4 is the third lens with refractive power, measured from the incident light side to the emitting light side. The second lens has a negative refractive power. The emitting surface 41 of the second lens 4 has a convex portion 411 located near the optical axis I and a convex portion 413 located near the circumference. The incident surface 42 of the second lens 4 has a concave portion 422 located near the optical axis I and a concave portion 424 located near the circumference. Both the emitting surface 41 and the incident surface 42 of the second lens 4 are aspherical.

[0113] The third lens 5 is the second lens with refractive index, measured from the incident light side to the emitting light side. The third lens 5 has a negative refractive index. The emitting surface 51 of the third lens 5 has a concave portion 512 located near the optical axis I and a concave portion 514 located near the circumference. The incident surface 52 of the third lens 5 has a concave portion 522 located near the optical axis I and a concave portion 524 located near the circumference. Both the emitting surface 51 and the incident surface 52 of the third lens 5 are aspherical.

[0114] The fourth lens 6 is the first lens with refractive index, measured from the incident light side to the emitting light side. The fourth lens 6 has a positive refractive index. The emitting surface 61 of the fourth lens 6 has a concave portion 612 located near the optical axis I and a concave portion 614 located near the circumference. The incident surface 62 of the fourth lens 6 has a convex portion 621 located near the optical axis I and a convex portion 623 located near the circumference. Both the emitting surface 61 and the incident surface 62 of the fourth lens 6 are aspherical.

[0115] In this embodiment, the angle between the emission direction of the main ray CF of the near-infrared light emitted from the emitting surface 100a of the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°.

[0116] Other detailed optical data for the first embodiment are as follows: Figure 9 As shown, the overall system focal length (EFL) of the optical lens group 10 in the first embodiment is 3.562 mm, the half field of view (HFOV) is 9.905°, the f-number (Fno) is 2.273, the system length is 2.738 mm, and the light circle radius is 0.603 mm. The system length refers to the distance along the optical axis I from the light-incident surface 31 of the first lens 3 to the light-emitting surface 100a. The "f-number" in this specification is calculated based on the principle of light reversibility, taking the aperture 2 as the entrance pupil.

[0117] Furthermore, in this embodiment, the eight surfaces of the first lens 3, the second lens 4, the third lens 5, and the fourth lens 6—the light-emitting surfaces 31, 41, 51, and 61, and the light-incident surfaces 32, 42, 52, and 62—are all aspherical surfaces. Among them, the light-emitting surfaces 31, 41, 51, and 61, and the light-incident surfaces 32, 42, 52, and 62 are general even-order aspherical surfaces. These aspherical surfaces are defined according to the following formula:

[0118]

[0119] in:

[0120] Y: The distance between a point on the aspherical curve and the optical axis I;

[0121] Z: Depth of the aspherical surface (a point on the aspherical surface at a distance Y from the optical axis I, and the distance between the point and the point tangent to the aspherical surface).

[0122] The tangent plane at the vertex on axis I, and the perpendicular distance between them;

[0123] R: Radius of curvature of the lens surface near the optical axis I;

[0124] K: Conic coefficient;

[0125] a i : The i-th order aspherical coefficient;

[0126] The aspherical coefficients of the light-exiting surface 31 of the first lens 3 to the light-incident surface 62 of the fourth lens 6 in formula (1) are as follows: Figure 10 As shown. Among them, Figure 10 The number 31 in the middle column indicates that it is the aspherical coefficient of the light-emitting surface 31 of the first lens 3, and the other columns follow the same principle.

[0127] Furthermore, the relationships between the important parameters in the optical lens group 10 of the first embodiment are as follows: Figure 75 , Figure 76 As shown, in Figure 75 The unit for each parameter is millimeters (mm).

[0128] in,

[0129] T1 is the thickness of the first lens 3 on the optical axis I;

[0130] T2 is the thickness of the second lens 4 on the optical axis I;

[0131] T3 is the thickness of the third lens 5 on the optical axis I;

[0132] T4 is the thickness of the fourth lens 6 on optical axis I;

[0133] G12 The air gap between the first lens 3 and the second lens 4 on the optical axis I;

[0134] G23 is the air gap between the second lens 4 and the third lens 5 on the optical axis I;

[0135] G34 is the air gap between the third lens 5 and the fourth lens 6 on the optical axis I;

[0136] AAG is the sum of the air gaps on the optical axis I between all the lenses with refractive indices in the optical lens group 10.

[0137] ALT is the sum of the thicknesses of all refractive lenses in the optical lens group 10 along the optical axis I.

[0138] TL is the distance on the optical axis I from the light-emitting surface 31 of the first lens 3 to the light-incident surface 62 of the fourth lens 6.

[0139] TTL is the distance on the optical axis I from the light-emitting surface of the first lens to the structured light generating unit of the multi-source light source, calculated from the number of light-emitting sides.

[0140] BFL is the distance from the light-incident surface 62 of the fourth lens 6 to the structured light generating unit of the multi-source light source on the optical axis I.

[0141] HFOV is the half field of view angle (denoted as ω, e.g.) Figure 1A (As shown in the diagram), is the maximum half-angle of light emission from optical lens group 10;

[0142] Fno is the aperture value, which is calculated based on the principle of light reversibility to obtain the effective aperture of the light beam emitted by the optical lens group 10. In the embodiment of the present invention, the aperture 2 is considered as the aperture value calculated by the entrance pupil.

[0143] LCR (Light Circular Radius) is the radius of the luminous circle (denoted as LCR, e.g., ...). Figure 1B (As shown in the diagram), is the radius of the smallest circumscribed circle of the emitting surface 100a of the multi-source structured light generating unit 15; and

[0144] EFL is the system focal length of optical lens group 10.

[0145] Furthermore, redefine:

[0146] f1 is the focal length of the first lens 3;

[0147] f2 is the focal length of the second lens 4;

[0148] f3 is the focal length of the third lens 5;

[0149] f4 is the focal length of the fourth lens 6;

[0150] n1 is the refractive index of the first lens 3;

[0151] n2 is the refractive index of the second lens 4;

[0152] n3 is the refractive index of the third lens 5;

[0153] n4 is the refractive index of the fourth lens 6;

[0154] V1 is the Abbe coefficient of the first lens 3;

[0155] V2 is the Abbe coefficient of the second lens 4;

[0156] V3 is the Abbe coefficient of the third lens 5; and

[0157] V4 is the Abbe coefficient of the fourth lens 6.

[0158] See also Figures 8A to 8D , Figure 8A The diagram illustrates the first embodiment, where the pupil radius is 0.7836 mm and the wavelengths are 930 nm, 940 nm, and 950 nm, and the longitudinal spherical aberration is observed on the emitting surface 100a. Figure 8B and Figure 8C The diagrams illustrate the field curvature aberrations in the sagittal and meridional directions on the emitting surface 100a of the first embodiment when the wavelengths are 930 nm, 940 nm, and 950 nm. Figure 8D The diagram illustrates the distortion aberration on the emitting surface 100a of the first embodiment when the wavelengths are 930 nm, 940 nm, and 950 nm. (Diagram showing the longitudinal spherical aberration of this first embodiment.) Figure 8A In the figure, the curves formed by each wavelength are very close and move towards the center, indicating that off-axis light rays at different heights of each wavelength are concentrated near the imaging point. The skewing of the curves for each wavelength shows that the imaging point deviation of off-axis light rays at different heights is controlled within ±10 micrometers. Therefore, this first embodiment does significantly improve spherical aberration of the same wavelength. In addition, the distances between the three representative wavelengths are also quite close, indicating that the imaging positions of light rays of different wavelengths are quite concentrated, thus significantly improving chromatic aberration.

[0159] exist Figure 8B and Figure 8C In the two field curvature aberration diagrams, the focal length variation for the three representative wavelengths falls within ±10 micrometers across the entire field of view, demonstrating that the optical lens group of this first embodiment can effectively eliminate aberrations. Figure 8D The distortion aberration diagram shows that the distortion aberration of the first embodiment is maintained within the range of ±3.5%, indicating that the distortion aberration of the first embodiment meets the imaging quality requirements of the optical lens group. Based on this, it can be seen that the first embodiment can still provide good imaging quality compared with existing optical lenses, even with the system length shortened to about 2.738 mm. Therefore, the first embodiment can shorten the length of the optical lens group while maintaining good optical performance.

[0160] Figure 11This is a schematic diagram of the optical lens assembly according to the second embodiment of the present invention. Figures 12A to 12D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the second embodiment. Please refer to [the diagram first]. Figure 11 A second embodiment of the optical lens group 10 of the present invention is generally similar to the first embodiment, but the differences are as follows: the optical data, aspherical coefficients, and parameters of these lenses 3, 4, 5, and 6 are more or less different. Furthermore, the light-incident surface 32 of the first lens 3 has a convex portion 321 located near the optical axis I. The light-exit surface 41 of the second lens 4 has a concave portion 412 located near the optical axis I. The light-incident surface 42 of the second lens 4 has a convex portion 421 located near the optical axis I and a convex portion 423 located near the circumference. The light-exit surface 51 of the third lens 5 has a convex portion 511 located near the optical axis I and a convex portion 513 located near the circumference. In addition, the principal ray of the near-infrared light emitted by the multi-source structured light generating unit 15 is less than 5°. It should be noted that, for clear visualization of the figures, Figure 11 The numbers of the concave and convex surfaces that are the same as those in the first embodiment are omitted.

[0161] In this embodiment, the angle between the emission direction of the main ray CF of the near-infrared light emitted from the emitting surface 100a of the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°.

[0162] Detailed optical data of the optical lens group 10 in the second embodiment are as follows: Figure 13 As shown, the overall system focal length of the optical lens group 10 in the second embodiment is 2.785 mm, the half field of view (HFOV) is 9.906°, the aperture value (Fno) is 2.273, the system length is 2.845 mm, and the radius of the emission circle is 0.471 mm.

[0163] like Figure 14 As shown, the aspherical coefficients of the light-emitting surface 31 of the first lens 3 to the light-incident surface 62 of the fourth lens 6 in the second embodiment are represented in formula (1).

[0164] Furthermore, the relationships between the important parameters in the optical lens group 10 of the second embodiment are as follows: Figure 75 , Figure 76 As shown.

[0165] The longitudinal spherical aberration diagram of this second embodiment when its pupil radius is 0.6128 mm. Figure 12A In this study, the imaging point deviation of off-axis rays at different altitudes was controlled within ±2.8 micrometers. Figure 12B and Figure 12C In the two field curvature aberration diagrams, the focal length variation for the three representative wavelengths falls within ±4.5 micrometers across the entire field of view. Figure 12D The distortion aberration diagram shows that the distortion aberration of this second embodiment is maintained within the range of ±3.5%.

[0166] As can be seen from the above description, the half-field angle of the second embodiment is larger than that of the first embodiment. The longitudinal spherical aberration of the second embodiment is smaller than that of the first embodiment. The field curvature of the second embodiment is smaller than that of the first embodiment.

[0167] Figure 15 This is a schematic diagram of the optical lens assembly according to the third embodiment of the present invention. Figures 16A to 16D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the third embodiment. Please refer to [the diagram first]. Figure 15 A third embodiment of the optical lens group 10 of the present invention is generally similar to the first embodiment, but the differences are as follows: the optical data, aspherical coefficients, and parameters of these lenses 3, 4, 5, and 6 are more or less different. In addition, the incident surface 52 of the third lens 5 has a convex portion 521 located in the region near the optical axis I. Furthermore, the angle between the principal ray CF of the near-infrared light emitted by the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°. It should be noted that, for clear visualization of the figures, Figure 15 The numbers of the concave and convex surfaces that are the same as those in the first embodiment are omitted.

[0168] In this embodiment, the angle between the emission direction of the main ray CF of the near-infrared light emitted from the emitting surface 100a of the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°.

[0169] Detailed optical data of the optical lens group 10 in the third embodiment are as follows: Figure 17 As shown, the overall system focal length of the optical lens group 10 in the third embodiment is 2.738 mm, the half field of view (HFOV) is 9.900°, the aperture value (Fno) is 2.273, the system length is 2.796 mm, and the radius of the emission circle is 0.496 mm.

[0170] like Figure 18 As shown, the aspherical coefficients of the light-emitting surface 31 of the first lens 3 to the light-incident surface 62 of the fourth lens 6 in the third embodiment are represented in formula (1).

[0171] Furthermore, the relationships between the important parameters in the optical lens group 10 of the third embodiment are as follows: Figure 75 , Figure 76 As shown.

[0172] The longitudinal spherical aberration diagram of this third embodiment when its pupil radius is 0.6023 mm. Figure 16AIn this study, the imaging point deviation of off-axis rays at different altitudes was controlled within ±3.0 micrometers. Figure 16B and Figure 16C In the two field curvature aberration diagrams, the focal length variation for the three representative wavelengths falls within ±4.5 micrometers across the entire field of view. Figure 16D The distortion aberration diagram shows that the distortion aberration of this third embodiment is maintained within the range of ±3.9%.

[0173] As can be seen from the above description, the longitudinal spherical aberration of the third embodiment is less than the longitudinal aberration of the first embodiment. The field curvature of the third embodiment is less than the field curvature of the first embodiment.

[0174] Figure 19 This is a schematic diagram of the optical lens assembly according to the fourth embodiment of the present invention. Figures 20A to 20D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the fourth embodiment. Please refer to [the diagram first]. Figure 19 A fourth embodiment of the optical lens group 10 of the present invention is generally similar to the first embodiment, but the differences are as follows: the optical data, aspherical coefficients, and parameters of these lenses 3, 4, 5, and 6 are more or less different. Additionally, the light-incident surface 52 of the third lens 5 has a convex portion 521 located near the optical axis I and a convex portion 523 located near the circumference. It should be noted that, for clearer illustration, Figure 19 The numbers of the concave and convex surfaces that are the same as those in the first embodiment are omitted.

[0175] In this embodiment, the angle between the emission direction of the main ray CF of the near-infrared light emitted from the emitting surface 100a of the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°.

[0176] Detailed optical data of the optical lens group 10 in the fourth embodiment are as follows: Figure 21 As shown, the overall system focal length of the optical lens group 10 in the fourth embodiment is 2.544 mm, the half field of view (HFOV) is 9.900°, the aperture value (Fno) is 2.273, the system length is 2.857 mm, and the radius of the emission circle is 0.467 mm.

[0177] like Figure 22 As shown, the aspherical coefficients of the light-emitting surface 31 of the first lens 3 to the light-incident surface 62 of the fourth lens 6 in formula (1) are the values ​​of each item.

[0178] Furthermore, the relationships between the important parameters in the optical lens group 10 of the fourth embodiment are as follows: Figure 75 , Figure 76 As shown.

[0179] The longitudinal spherical aberration diagram of this fourth embodiment when its pupil radius is 0.5596 mm. Figure 20A In this study, the imaging point deviation of off-axis rays at different altitudes was controlled within ±3.0 micrometers. Figure 20B and Figure 20C In the two field curvature aberration diagrams, the focal length variation for the three representative wavelengths falls within ±3.5 micrometers across the entire field of view. Figure 20D The distortion aberration diagram shows that the distortion aberration of this fourth embodiment is maintained within the range of ±5%.

[0180] As can be seen from the above description, the longitudinal spherical aberration of the fourth embodiment is less than the longitudinal aberration of the first embodiment. The field curvature of the fourth embodiment is less than the field curvature of the first embodiment.

[0181] Figure 23 This is a schematic diagram of the optical lens assembly according to the fifth embodiment of the present invention. Figures 24A to 24D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the fifth embodiment. Please refer to [the diagram first]. Figure 5 This invention provides a fifth embodiment of the optical lens group 10, which is generally similar to the first embodiment, but differs from it as follows: the optical data, aspherical coefficients, and parameters of lenses 3, 4, 5, and 6 are somewhat different. Additionally, the incident surface 52 of the third lens 5 has a convex portion 521 located near the optical axis I. It should be noted that, for clear visualization of the figures, Figure 23 The numbers of the concave and convex surfaces that are the same as those in the first embodiment are omitted.

[0182] In this embodiment, the angle between the emission direction of the main ray CF of the near-infrared light emitted from the emitting surface 100a of the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°.

[0183] Detailed optical data of the optical lens group 10 in the fifth embodiment are as follows: Figure 25 As shown, the overall system focal length of the optical lens group 10 in the fifth embodiment is 2.616 mm, the half field of view (HFOV) is 9.893°, the aperture value (Fno) is 2.273, the system length is 2.940 mm, and the radius of the emission circle is 0.476 mm.

[0184] like Figure 26 As shown, the aspherical coefficients of the light-emitting surface 31 of the first lens 3 to the light-incident surface 62 of the fourth lens 6 in the fifth embodiment are represented in formula (1).

[0185] Furthermore, the relationships between the important parameters in the optical lens group 10 of the fifth embodiment are as follows: Figure 75 , Figure 76 As shown.

[0186] The longitudinal spherical aberration diagram of this fifth embodiment when its pupil radius is 0.5756 mm. Figure 24A In this study, the imaging point deviation of off-axis rays at different altitudes was controlled within ±3.3 micrometers. Figure 24B and Figure 24C In the two field curvature aberration diagrams, the focal length variation for the three representative wavelengths falls within ±4.0 micrometers across the entire field of view. Figure 24D The distortion aberration diagram shows that the distortion aberration of this fifth embodiment is maintained within the range of ±4.5%.

[0187] As can be seen from the above description, the longitudinal spherical aberration of the fifth embodiment is less than that of the first embodiment. The field curvature of the fifth embodiment is less than that of the first embodiment.

[0188] Figure 27 This is a schematic diagram of the optical lens assembly according to the sixth embodiment of the present invention. Figures 28A to 28D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the sixth embodiment. Please refer to [the diagram first]. Figure 27 This invention provides a sixth embodiment of the optical lens group 10, which is generally similar to the first embodiment, but differs from the first embodiment in the following ways: the optical data, aspherical coefficients, and parameters of lenses 3, 4, 5, and 6 are somewhat different. Additionally, the light-emitting surface 41 of the second lens 4 has a concave portion 412 located near the optical axis I. The light-entry surface of the third lens 5 has a convex portion 521 located near the optical axis I. The light-emitting surface 61 of the fourth lens 6 has a convex portion 613 located near the circumference. It should be noted that, for clear visualization of the figures, Figure 27 The numbers of the concave and convex surfaces that are the same as those in the first embodiment are omitted.

[0189] In this embodiment, the angle between the emission direction of the main ray CF of the near-infrared light emitted from the emitting surface 100a of the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°.

[0190] Detailed optical data of the optical lens group 10 in the sixth embodiment are as follows: Figure 29 As shown, the overall system focal length of the optical lens group 10 in the sixth embodiment is 3.022 mm, the half field of view (HFOV) is 9.895°, the aperture value (Fno) is 2.273, the system length is 2.861 mm, and the radius of the emission circle is 0.587 mm.

[0191] like Figure 30 As shown, the aspherical coefficients of the light-emitting surface 31 of the first lens 3 to the light-incident surface 62 of the fourth lens 6 in the sixth embodiment are represented in formula (1).

[0192] Furthermore, the relationships between the important parameters in the optical lens group 10 of the sixth embodiment are as follows: Figure 75 , Figure 76 As shown.

[0193] This sixth embodiment illustrates the longitudinal spherical aberration when its pupil radius is 0.6648 mm. Figure 28A In this study, the imaging point deviation of off-axis rays at different altitudes was controlled within ±5.5 micrometers. Figure 28B and Figure 28C In the two field curvature aberration diagrams, the focal length variation for the three representative wavelengths falls within ±25 micrometers across the entire field of view. Figure 28D The distortion aberration diagram shows that the distortion aberration of this sixth embodiment is maintained within the range of ±12%.

[0194] As can be seen from the above description, the longitudinal spherical aberration of the sixth embodiment is smaller than the longitudinal aberration of the first embodiment.

[0195] Figure 31 This is a schematic diagram of the optical lens assembly according to the seventh embodiment of the present invention. Figures 32A to 32D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the seventh embodiment. Please refer to [the diagram first]. Figure 31 A seventh embodiment of the optical lens group 10 of the present invention is generally similar to the first embodiment, but the differences are as follows: the optical data, aspherical coefficients, and parameters between these lenses 3, 4, 5, and 6 are more or less different. In addition, the second lens 4 has a positive refractive index. The incident surface 32 of the first lens 3 is spherical. It should be noted that, for clearer display of the figures, Figure 31 The numbers of the concave and convex surfaces that are the same as those in the first embodiment are omitted.

[0196] In this embodiment, the angle between the emission direction of the main ray CF of the near-infrared light emitted from the emitting surface 100a of the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°.

[0197] Detailed optical data of the optical lens group 10 in the seventh embodiment are as follows: Figure 33 As shown, the overall system focal length of the optical lens group 10 in the seventh embodiment is 2.696 mm, the half field of view (HFOV) is 10.490°, the aperture value (Fno) is 2.273, the system length is 2.697 mm, and the radius of the emission circle is 0.500 mm.

[0198] like Figure 34 As shown, the aspherical coefficients of the light-emitting surface 31 of the first lens 3 to the light-incident surface 62 of the fourth lens 6 in the seventh embodiment are represented in formula (1).

[0199] Furthermore, the relationships between the important parameters in the optical lens group 10 of the seventh embodiment are as follows: Figure 77 , Figure 78 As shown, in Figure 77 The unit for each parameter is millimeters (mm).

[0200] This seventh embodiment is illustrated with a longitudinal spherical aberration diagram when its pupil radius is 0.5932 mm. Figure 32A In this study, the imaging point deviation of off-axis rays at different altitudes was controlled within ±6.0 micrometers. Figure 32B and Figure 32C In the two field curvature aberration diagrams, the focal length variation for the three representative wavelengths falls within ±18 micrometers across the entire field of view. Figure 32D The distortion aberration diagram shows that the distortion aberration of this seventh embodiment is maintained within the range of ±0.045%.

[0201] As can be seen from the above description, the system length of the seventh embodiment is shorter than that of the first embodiment. The half-field of view of the seventh embodiment is larger than that of the first embodiment. The longitudinal spherical aberration of the seventh embodiment is smaller than that of the first embodiment.

[0202] Figure 35 This is a schematic diagram of the optical lens assembly according to the eighth embodiment of the present invention. Figures 36A to 36D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the eighth embodiment. Please refer to [the diagram first]. Figure 35 An eighth embodiment of the optical lens group 10 of the present invention is generally similar to the first embodiment, but the differences are as follows: the optical data, aspherical coefficients, and parameters of lenses 3, 4, 5, and 6 are more or less different. In addition, the light-incident surface 52 of the third lens 5 has a convex portion 521 located near the optical axis I. It should be noted that, for clearer illustration, Figure 35 The numbers of the concave and convex surfaces that are the same as those in the first embodiment are omitted.

[0203] In this embodiment, the angle between the emission direction of the main ray CF of the near-infrared light emitted from the emitting surface 100a of the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°.

[0204] Detailed optical data of the optical lens group 10 of the eighth embodiment are as follows: Figure 37 As shown, the overall system focal length of the optical lens group 10 in the eighth embodiment is 2.883 mm, the half field of view (HFOV) is 9.898°, the aperture value (Fno) is 2.273, the system length is 3.039 mm, and the radius of the emission circle is 0.525 mm.

[0205] like Figure 38As shown, the aspherical coefficients of the light-emitting surface 31 of the first lens 3 to the light-incident surface 62 of the fourth lens 6 in the eighth embodiment are represented in formula (1).

[0206] Furthermore, the relationships between the important parameters in the optical lens group 10 of the eighth embodiment are as follows: Figure 77 , Figure 78 As shown.

[0207] This eighth embodiment is illustrated with a longitudinal spherical aberration diagram when its pupil radius is 0.6343 mm. Figure 36A In this study, the imaging point deviation of off-axis rays at different altitudes was controlled within ±3 micrometers. Figure 36B and Figure 36C In the two field curvature aberration diagrams, the focal length variation for the three representative wavelengths falls within ±4.0 micrometers across the entire field of view. Figure 36D The distortion aberration diagram shows that the distortion aberration of this eighth embodiment is maintained within the range of ±4.5%.

[0208] As can be seen from the above description, the longitudinal spherical aberration of the eighth embodiment is less than that of the first embodiment. The field curvature of the eighth embodiment is less than that of the first embodiment.

[0209] Figure 39 A schematic diagram of the optical lens assembly of the ninth embodiment of the present invention, and Figures 40A to 40D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the ninth embodiment. Please refer to [the diagram first]. Figure 42 A ninth embodiment of the optical lens group 10 of the present invention is generally similar to the first embodiment, but the difference is as follows: The optical lens group 10 of the ninth embodiment of the present invention includes, from the light-emitting side to the light-receiving side, an aperture 2, a fifth lens 7, a first lens 3, a second lens 4, a third lens 5, and a fourth lens 6 along the optical axis I of the optical lens group 10. When multiple near-infrared lights are emitted from the light-emitting surface 100a of the multi-source structured light generating unit 15 and enter the optical lens group 10, the multiple near-infrared lights are sequentially passed through the fourth lens 6, the third lens 5, the second lens 4, the first lens 3, the fifth lens 7, and the aperture 2 to generate multiple beams, which are then emitted from the optical lens group 10.

[0210] The fifth lens 7, the first lens 3, the second lens 4, the third lens 5 and the fourth lens 6 each have an emitting surface 71, 31, 41, 51, 61 facing the light-emitting side and allowing multiple near-infrared lights to pass through, and an incident surface 72, 32, 42, 52, 62 facing the light-incident side and allowing multiple near-infrared lights to pass through.

[0211] A fifth lens 7 is positioned in front of the first lens 3. The fifth lens 7 has a positive refractive index. The light-emitting surface 71 of the fifth lens 7 has a convex portion 711 located near the optical axis I and a convex portion 713 located near the circumference. The light-entry surface 72 of the fifth lens 7 has a concave portion 722 located near the optical axis I and a concave portion 724 located near the circumference. Both the light-emitting surface 71 and the light-entry surface 72 of the fifth lens 7 are aspherical. The fifth lens 7 is made of plastic.

[0212] The incident surface 32 of the first lens 3 is spherical.

[0213] The fourth lens 6 has a negative refractive index. The incident surface 62 of the fourth lens 6 has a concave portion 622 located near the optical axis I. It should be noted that, for clear visualization of the diagram, Figure 39 The numbers of the concave and convex surfaces that are the same as those in the first embodiment are omitted.

[0214] In this embodiment, the angle between the emission direction of the main ray CF of the near-infrared light emitted from the emitting surface 100a of the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°.

[0215] Other detailed optical data for the ninth embodiment are as follows: Figure 41 As shown, the overall system focal length (EFL) of the ninth embodiment is 3.930 mm, the half field of view (HFOV) is 7.694°, the aperture value (F-number, Fno) is 2.273, the system length is 2.948 mm, and the emission circle radius is 0.500 mm. The system length refers to the distance along the optical axis I from the light-emitting surface 71 of the fifth lens 7 to the light-emitting surface 100.

[0216] Furthermore, in the ninth embodiment, the light-emitting surfaces 71, 31, 41, 51, 61 and the light-incident surfaces 72, 42, 52, 62 of the fifth lens 7, the first lens 3, the second lens 4, the third lens 5 and the fourth lens 6, totaling nine surfaces, are aspherical. These aspherical surfaces are defined according to formula (1), and will not be elaborated further here. The aspherical coefficients of the light-emitting surface 31 of the first lens 3 to the light-incident surface 72 of the fifth lens 7 in formula (1) are as follows: Figure 42 As shown. Among them, Figure 42 The column number indicates the aspherical coefficient of the light-emitting surface 31 of the first lens 3, and so on for the other columns.

[0217] Furthermore, the relationships between the important parameters in the optical lens group 10 of the ninth embodiment are as follows: Figure 77 as well as Figure 78 As shown.

[0218] The parameter definitions of the first lens 3, second lens 4, third lens 5, and fourth lens 6 mentioned in this ninth embodiment are roughly similar to the parameter definitions mentioned in paragraph 0029 of this specification, with the following differences:

[0219] T5 is the thickness of the fifth lens 7 on optical axis I;

[0220] G51 is the air gap between the fifth lens 7 and the first lens 3 on the optical axis I;

[0221] f5 is the focal length of the fifth lens 7;

[0222] n5 is the refractive index of the fifth lens 7; and

[0223] υ5 is the Abbe coefficient of the fifth lens 7.

[0224] See also Figures 40A to 40D , Figure 40A The diagram illustrates the first embodiment, where the pupil radius is 0.7836 mm and the wavelengths are 930 nm, 940 nm, and 950 nm, the longitudinal spherical aberration on the emitting surface 100a. Figure 40B and Figure 40C The diagrams illustrate the field curvature aberrations in the sagittal and meridional directions on the emitting surface 100a of the first embodiment when the wavelengths are 930 nm, 940 nm, and 950 nm. Figure 40D The diagram illustrates the distortion aberration on the emitting surface 100a of the first embodiment when the wavelengths are 930 nm, 940 nm, and 950 nm. The diagram also shows the longitudinal spherical aberration of this ninth embodiment. Figure 40A In the figure, the curves formed by each wavelength are very close and move towards the center, indicating that off-axis light rays at different heights of each wavelength are concentrated near the imaging point. It can be seen from the skewing of the curves for each wavelength that the imaging point deviation of off-axis light rays at different heights is controlled within the range of ±58 micrometers. Therefore, this ninth embodiment does significantly improve spherical aberration of the same wavelength. In addition, the distances between the three representative wavelengths are also quite close, indicating that the imaging positions of light rays of different wavelengths are quite concentrated, thus significantly improving chromatic aberration.

[0225] exist Figure 40B and Figure 40CIn the two field curvature diagrams, the focal length variation for the three representative wavelengths falls within ±60 micrometers across the entire field of view, demonstrating that the optical system of this ninth embodiment can effectively eliminate field curvature aberrations. Figure 40D The distortion diagram shows that the distortion aberration of this ninth embodiment is maintained within the range of ±8.0%, indicating that the distortion aberration of this ninth embodiment meets the imaging quality requirements of the optical lens group. Therefore, this ninth embodiment can still provide better imaging quality than existing optical lens groups, even with the system length shortened to about 2.948 mm. Thus, this ninth embodiment can shorten the length of the optical lens group while maintaining good optical performance.

[0226] Figure 43 This is a schematic diagram of the optical lens assembly according to the tenth embodiment of the present invention. Figures 44A to 44D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the tenth embodiment. Please refer to [the diagram first]. Figure 43 This invention provides a tenth embodiment of the optical lens group 10, which is generally similar to the ninth embodiment, but differs from the following: the optical data, aspherical coefficients, and parameters of lenses 3, 4, 5, 6, and 7 are more or less different. Additionally, the second lens 4 has a positive refractive index. The third lens 5 has a positive refractive index. The incident surface 52 of the third lens 5 has a convex portion 521 located near the optical axis I. The emitting surface 61 of the fourth lens 6 has a convex portion 611 located near the optical axis I and a convex portion 613 located near the circumference. The incident surface 62 of the fourth lens 6 has a concave portion 624 located near the circumference. Furthermore, the angle between the principal ray CF of the near-infrared light emitted by the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°. It should be noted that, for clear visualization of the figures, Figure 43 The numbers for the concave and convex surfaces that are the same as those in the ninth embodiment are omitted.

[0227] In this embodiment, the angle between the emission direction of the main ray CF of the near-infrared light emitted from the emitting surface 100a of the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°.

[0228] Detailed optical data of the optical lens group 10 of the tenth embodiment are as follows: Figure 45 As shown, the overall system focal length of the optical lens group 10 in the tenth embodiment is 2.825 mm, the half field of view (HFOV) is 9.863°, the aperture value (Fno) is 2.273, the system length is 3.881 mm, and the radius of the emission circle is 0.500 mm.

[0229] like Figure 46As shown, the aspherical coefficients of the light-emitting surface 71 of the fifth lens 7 to the light-incident surface 62 of the fourth lens 6 in the tenth embodiment are represented in formula (1).

[0230] Furthermore, the relationships between the important parameters in the optical lens group 10 of the tenth embodiment are as follows: Figure 77 , Figure 78 As shown.

[0231] This tenth embodiment is illustrated with a longitudinal spherical aberration diagram when its pupil radius is 0.6215 mm. Figure 44A In this study, the imaging point deviation of off-axis rays at different altitudes was controlled within ±3.0 micrometers. Figure 44B and Figure 44C In the two field curvature aberration diagrams, the focal length variation for the three representative wavelengths falls within ±12 micrometers across the entire field of view. Figure 44D The distortion aberration diagram shows that the distortion aberration of this tenth embodiment is maintained within the range of ±1.4%.

[0232] From the above description, it can be seen that: the half-field angle of the tenth embodiment is greater than that of the ninth embodiment. The longitudinal spherical aberration of the tenth embodiment is less than that of the ninth embodiment. The field curvature of the tenth embodiment is less than that of the ninth embodiment. The distortion aberration of the tenth embodiment is less than that of the ninth embodiment.

[0233] Figure 47 This is a schematic diagram of the optical lens assembly according to the eleventh embodiment of the present invention. Figures 48A to 48D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the eleventh embodiment. Please refer to [the diagram first]. Figure 47 This eleventh embodiment of the optical lens group 10 of the present invention is generally similar to the ninth embodiment, but the differences are as follows: the optical data, aspherical coefficients, and parameters of lenses 3, 4, 5, 6, and 7 are more or less different. Additionally, the fourth lens 6 has a positive refractive index. The incident surface 52 of the third lens 5 has a convex portion 521 located near the optical axis I and a convex portion 523 located near the circumference. The incident surface 62 of the fourth lens 6 has a convex portion 621 located near the optical axis I. Furthermore, the angle between the principal ray CF of the near-infrared light emitted by the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°. It should be noted that, for clear visualization of the figures, Figure 47 The numbers for the concave and convex surfaces that are the same as those in the ninth embodiment are omitted.

[0234] In this embodiment, the angle between the emission direction of the main ray CF of the near-infrared light emitted from the emitting surface 100a of the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°.

[0235] Detailed optical data of the optical lens group 10 in the eleventh embodiment are as follows: Figure 49 As shown, the overall system focal length of the optical lens group 10 in the eleventh embodiment is 2.672 mm, the half field of view (HFOV) is 9.942°, the aperture value (Fno) is 2.273, the system length is 2.814 mm, and the radius of the emission circle is 0.500 mm.

[0236] like Figure 50 As shown, the aspherical coefficients of the light-emitting surface 71 of the fifth lens 7 to the light-incident surface 62 of the fourth lens 6 in the eleventh embodiment are represented in formula (1).

[0237] Furthermore, the relationships between the important parameters in the optical lens group 10 of the eleventh embodiment are as follows: Figure 77 , Figure 78 As shown.

[0238] The longitudinal spherical aberration diagram of this eleventh embodiment when its pupil radius is 0.5879 mm. Figure 48A In this study, the imaging point deviation of off-axis rays at different altitudes was controlled within ±1.6 micrometers. Figure 48B and Figure 48C In the two field curvature aberration diagrams, the focal length variation for the three representative wavelengths falls within ±3.0 micrometers across the entire field of view. Figure 48D The distortion aberration diagram shows that the distortion aberration of this eleventh embodiment is maintained within the range of ±6.0%.

[0239] From the above description, it can be seen that: the system length of the eleventh embodiment is shorter than that of the ninth embodiment. The half-field angle of the eleventh embodiment is greater than that of the ninth embodiment. The longitudinal spherical aberration of the eleventh embodiment is less than that of the ninth embodiment. The field curvature of the eleventh embodiment is less than that of the ninth embodiment. The distortion aberration of the eleventh embodiment is less than that of the ninth embodiment.

[0240] Figure 51 This is a schematic diagram of the optical lens assembly according to the twelfth embodiment of the present invention. Figures 52A to 52D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the twelfth embodiment. Please refer to [the diagram first]. Figure 51 This is a twelfth embodiment of the optical lens group 10 of the present invention, which is generally similar to the ninth embodiment, but the differences are as follows: the optical data, aspherical coefficients, and parameters of these lenses 3, 4, 5, 6, and 7 are more or less different. In addition, the incident surface 62 of the fourth lens 6 has a convex portion 621 located in the region near the optical axis I. Furthermore, the angle between the principal ray CF of the near-infrared light emitted by the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°. It should be noted that, for clear display of the figures, Figure 51The numbers for the concave and convex surfaces that are the same as those in the ninth embodiment are omitted.

[0241] In this embodiment, the angle between the emission direction of the main ray CF of the near-infrared light emitted from the emitting surface 100a of the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°.

[0242] Detailed optical data of the optical lens group 10 in the twelfth embodiment are as follows: Figure 53 As shown, the overall system focal length of the optical lens group 10 in the twelfth embodiment is 2.899 mm, the half field of view (HFOV) is 9.943°, the aperture value (Fno) is 2.273, the system length is 3.113 mm, and the radius of the emission circle is 0.500 mm.

[0243] like Figure 54 As shown, the aspherical coefficients of the light-emitting surface 71 of the fifth lens 7 to the light-incident surface 62 of the fourth lens 6 in formula (1) are the values ​​of each item.

[0244] Furthermore, the relationships between the important parameters in the optical lens group 10 of the twelfth embodiment are as follows: Figure 77 , Figure 78 As shown.

[0245] The longitudinal spherical aberration diagram of this twelfth embodiment when its pupil radius is 0.6377 mm. Figure 52A In this study, the imaging point deviation of off-axis rays at different altitudes was controlled within ±25 micrometers. Figure 52B and Figure 52C In the two field curvature aberration diagrams, the focal length variation for the three representative wavelengths falls within ±30.0 micrometers across the entire field of view. Figure 52D The distortion aberration diagram shows that the distortion aberration of this twelfth embodiment is maintained within the range of ±1.4%.

[0246] From the above description, it can be seen that: the half-field angle of the twelfth embodiment is greater than that of the ninth embodiment. The longitudinal spherical aberration of the twelfth embodiment is less than that of the ninth embodiment. The field curvature of the twelfth embodiment is less than that of the ninth embodiment. The distortion aberration of the twelfth embodiment is less than that of the ninth embodiment.

[0247] Figure 55 This is a schematic diagram of the optical lens assembly according to the thirteenth embodiment of the present invention. Figures 56A to 56D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the thirteenth embodiment. Please refer to [the diagram first]. Figure 55This is a thirteenth embodiment of the optical lens group 10 of the present invention, which is generally similar to the ninth embodiment, but the differences are as follows: the optical data, aspherical coefficients, and parameters of these lenses 3, 4, 5, 6, and 7 are more or less different. In addition, the fifth lens 7 has a negative refractive index. The second lens 4 has a positive refractive index. The fourth lens 6 has a positive refractive index. The incident surface 62 of the fourth lens 6 is a convex surface, and it has a convex portion 621 located in the region near the optical axis I. Furthermore, the angle between the principal ray CF of the near-infrared light emitted by the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°. It should be noted that, for clear display of the figures, Figure 55 The numbers for the concave and convex surfaces that are the same as those in the ninth embodiment are omitted.

[0248] In this embodiment, the angle between the emission direction of the main ray CF of the near-infrared light emitted from the emitting surface 100a of the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°.

[0249] Detailed optical data of the optical lens group 10 in the thirteenth embodiment are as follows: Figure 57 As shown, the overall system focal length of the optical lens group 10 in the thirteenth embodiment is 2.797 mm, the half field of view (HFOV) is 9.939°, the aperture value (Fno) is 2.273, the system length is 2.748 mm, and the radius of the emission circle is 0.500 mm.

[0250] like Figure 58 As shown, the aspherical coefficients of the light-emitting surface 71 of the fifth lens 7 to the light-incident surface 62 of the fourth lens 6 in the thirteenth embodiment are in formula (1).

[0251] Furthermore, the relationships between the important parameters in the optical lens group 10 of the thirteenth embodiment are as follows: Figure 79 , Figure 80 As shown, in Figure 79 The unit for each parameter is millimeters (mm).

[0252] The longitudinal spherical aberration diagram of this thirteenth embodiment when its pupil radius is 0.6154 mm. Figure 56A In this study, the imaging point deviation of off-axis rays at different altitudes was controlled within ±2.5 micrometers. Figure 56B and Figure 56C In the two field curvature aberration diagrams, the focal length variation for the three representative wavelengths falls within ±5.0 micrometers across the entire field of view. Figure 56D The distortion aberration diagram shows that the distortion aberration of this thirteenth embodiment is maintained within the range of ±2.0%.

[0253] Figure 59 This is a schematic diagram of the optical lens assembly according to the fourteenth embodiment of the present invention. Figures 60A to 60D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the fourteenth embodiment. Please refer to [the diagram first]. Figure 59 This is a fourteenth embodiment of the optical lens group 10 of the present invention, which is generally similar to the ninth embodiment, but the differences are as follows: the optical data, aspherical coefficients, and parameters of these lenses 3, 4, 5, 6, and 7 are more or less different. Additionally, the second lens 4 has a positive refractive index. The incident surface 62 of the fourth lens 6 has a convex portion 621 located in the region near the optical axis I. Furthermore, the angle between the principal ray CF of the near-infrared light emitted by the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°. It should be noted that, for clear visualization of the figures, Figure 59 The numbers for the concave and convex surfaces that are the same as those in the ninth embodiment are omitted.

[0254] In this embodiment, the angle between the emission direction of the main ray CF of the near-infrared light emitted from the emitting surface 100a of the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°.

[0255] Detailed optical data of the optical lens group 10 in the fourteenth embodiment are as follows: Figure 61 As shown, the overall system focal length of the optical lens group 10 in the fourteenth embodiment is 2.765 mm, the half field of view (HFOV) is 9.941°, the aperture value (Fno) is 2.273, the system length is 3.157 mm, and the radius of the emission circle is 0.500 mm.

[0256] like Figure 62 As shown, the aspherical coefficients of the light-emitting surface 71 of the fifth lens 7 to the light-incident surface 62 of the fourth lens 6 in formula (1) are the values ​​of each item.

[0257] Furthermore, the relationships between the important parameters in the optical lens group 10 of the fourteenth embodiment are as follows: Figure 79 , Figure 80 As shown.

[0258] The longitudinal spherical aberration diagram of this fourteenth embodiment when its pupil radius is 0.6083 mm. Figure 60A In this study, the imaging point deviation of off-axis rays at different altitudes was controlled within ±1.5 micrometers. Figure 60B and Figure 60C In the two field curvature aberration diagrams, the focal length variation for the three representative wavelengths falls within ±3.0 micrometers across the entire field of view. Figure 60D The distortion aberration diagram shows that the distortion aberration of this fourteenth embodiment is maintained within the range of ±2.5%.

[0259] From the above description, it can be seen that: the half-field angle of the fourteenth embodiment is greater than that of the ninth embodiment. The longitudinal spherical aberration of the fourteenth embodiment is less than that of the ninth embodiment. The field curvature of the fourteenth embodiment is less than that of the ninth embodiment. The distortion aberration of the fourteenth embodiment is less than that of the ninth embodiment.

[0260] Figure 63 This is a schematic diagram of the optical lens assembly according to the fifteenth embodiment of the present invention. Figures 64A to 64D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the fifteenth embodiment. Please refer to [the diagram first]. Figure 63 This is a fifteenth embodiment of the optical lens group 10 of the present invention, which is generally similar to the ninth embodiment, but the differences are as follows: the optical data, aspherical coefficients, and parameters of these lenses 3, 4, 5, 6, and 7 are more or less different. In addition, the fourth lens 6 has a positive refractive index. The light-incident surface 42 of the second lens 4 has a convex portion 423 located in the region near the circumference. The light-incident surface 52 of the third lens 5 has a convex portion 521 located in the region near the optical axis I and a convex portion 523 located in the region near the circumference. The light-exit surface 61 of the fourth lens 6 has a convex portion 611 located in the region near the optical axis I and a convex portion 613 located in the region near the circumference. The light-incident surface 62 of the fourth lens 6 has a concave portion 624 located in the region near the circumference. Furthermore, the angle between the principal ray CF of the near-infrared light emitted by the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°. It should be noted that, for clear display of the figures, Figure 63 The numbers for the concave and convex surfaces that are the same as those in the ninth embodiment are omitted.

[0261] In this embodiment, the angle between the emission direction of the main ray CF of the near-infrared light emitted from the emitting surface 100a of the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°.

[0262] Detailed optical data of the optical lens group 10 in the fifteenth embodiment are as follows: Figure 65 As shown, the overall system focal length of the optical lens group 10 in the fifteenth embodiment is 2.754 mm, the half field of view (HFOV) is 9.941°, the aperture value (Fno) is 2.273, the system length is 3.433 mm, and the radius of the emission circle is 0.500 mm.

[0263] like Figure 66 As shown, the aspherical coefficients of the light-emitting surface 71 of the fifth lens 7 to the light-incident surface 62 of the fourth lens 6 in formula (1) are the values ​​of each item.

[0264] Furthermore, the relationships between the important parameters in the optical lens group 10 of the fifteenth embodiment are as follows: Figure 79 , Figure 80 As shown.

[0265] The longitudinal spherical aberration diagram of this fifteenth embodiment when its pupil radius is 0.6058 mm. Figure 64A In this study, the imaging point deviation of off-axis rays at different altitudes was controlled within ±4.5 micrometers. Figure 64B and Figure 64C In the two field curvature aberration diagrams, the focal length variation for the three representative wavelengths falls within ±5.0 micrometers across the entire field of view. Figure 64D The distortion aberration diagram shows that the distortion aberration of this fifteenth embodiment is maintained within the range of ±3.0%.

[0266] From the above description, it can be seen that: the half-field angle of the fifteenth embodiment is greater than that of the ninth embodiment; the longitudinal spherical aberration of the fifteenth embodiment is less than that of the ninth embodiment; the field curvature of the fifteenth embodiment is less than that of the ninth embodiment; and the distortion aberration of the fifteenth embodiment is less than that of the ninth embodiment.

[0267] Figure 67 This is a schematic diagram of the optical lens assembly according to the sixteenth embodiment of the present invention. Figures 68A to 68D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the sixteenth embodiment. Please refer to [the diagram first]. Figure 67 This is a sixteenth embodiment of the optical lens group 10 of the present invention, which is generally similar to the ninth embodiment, but the differences are as follows: the optical data, aspherical coefficients, and parameters of these lenses 3, 4, 5, 6, and 7 are more or less different. In addition, the fourth lens 6 has a positive refractive index. The light-incident surface 32 of the first lens 3 has a convex portion 321 located near the optical axis I and a convex portion 323 located near the circumference. The light-incident surface 62 of the fourth lens 6 has a convex portion 621 located near the optical axis I. The first lens 3 is made of plastic. The fifth lens 7 is made of glass with a refractive index greater than 1.8. Furthermore, the angle between the principal ray CF of the near-infrared light emitted by the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°. It should be noted that, for clear visualization of the figures, Figure 67 The numbers for the concave and convex surfaces that are the same as those in the ninth embodiment are omitted.

[0268] In this embodiment, the angle between the emission direction of the main ray CF of the near-infrared light emitted from the emitting surface 100a of the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°.

[0269] Detailed optical data of the optical lens group 10 of the sixteenth embodiment are as follows: Figure 69As shown, the overall system focal length of the optical lens group 10 in the sixteenth embodiment is 2.700 mm, the half field of view (HFOV) is 10.491°, the aperture value (Fno) is 2.273, the system length is 3.110 mm, and the radius of the emission circle is 0.500 mm.

[0270] like Figure 70 As shown, the aspherical coefficients of the light-emitting surface 71 of the fifth lens 7 to the light-incident surface 62 of the fourth lens 6 in the sixteenth embodiment are in formula (1).

[0271] Furthermore, the relationships between the important parameters in the optical lens group 10 of the sixteenth embodiment are as follows: Figure 79 , Figure 80 As shown.

[0272] The longitudinal spherical aberration diagram of this sixteenth embodiment when its pupil radius is 0.5939 mm. Figure 68A In this study, the imaging point deviation of off-axis rays at different altitudes was controlled within ±4.5 micrometers. Figure 68B and Figure 68C In the two field curvature aberration diagrams, the focal length variation for the three representative wavelengths falls within ±25 micrometers across the entire field of view. Figure 68D The distortion aberration diagram shows that the distortion aberration of this sixteenth embodiment is maintained within the range of ±0.03%.

[0273] From the above description, it can be seen that: the half-field angle of the sixteenth embodiment is greater than that of the ninth embodiment. The longitudinal spherical aberration of the sixteenth embodiment is less than that of the ninth embodiment. The field curvature of the sixteenth embodiment is less than that of the ninth embodiment. The distortion aberration of the sixteenth embodiment is less than that of the ninth embodiment.

[0274] Figure 71 This is a schematic diagram of the optical lens assembly according to the seventeenth embodiment of the present invention. Figures 72A to 72D This is a diagram showing the longitudinal spherical aberration and various aberrations of the optical lens group in the seventeenth embodiment. Please refer to [the diagram first]. Figure 71This is a seventeenth embodiment of the optical lens group 10 of the present invention, which is generally similar to the ninth embodiment, but the differences are as follows: the optical data, aspherical coefficients, and parameters of these lenses 3, 4, 5, 6, and 7 are more or less different. In addition, the second lens 4 has a positive refractive index. The third lens 5 has a positive refractive index. The light-incident surface 52 of the third lens 5 has a convex portion 521 located near the optical axis I and a convex portion 523 located near the circumference. The light-exit surface 61 of the fourth lens 6 has a convex portion 611 located near the optical axis I and a convex portion 613 located near the circumference. The light-incident surface 62 of the fourth lens 6 has a concave portion 624 located near the circumference. Furthermore, the angle between the principal ray CF of the near-infrared light emitted by the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°. It should be noted that, for clear display of the figures, Figure 71 The numbers for the concave and convex surfaces that are the same as those in the ninth embodiment are omitted.

[0275] In this embodiment, the angle between the emission direction of the main ray CF of the near-infrared light emitted from the emitting surface 100a of the multi-source structured light generating unit 15 and the normal direction D of the emitting surface 100a is less than 5°.

[0276] Detailed optical data of the optical lens group 10 of the seventeenth embodiment are as follows: Figure 73 As shown, the overall system focal length of the optical lens group 10 in the seventeenth embodiment is 2.742 mm, the half field of view (HFOV) is 9.937°, the aperture value (Fno) is 2.273, the system length is 3.978 mm, and the radius of the emission circle is 0.500 mm.

[0277] like Figure 74 As shown, the aspherical coefficients of the light-emitting surface 71 of the fifth lens 7 to the light-incident surface 62 of the fourth lens 6 in the seventeenth embodiment are in formula (1).

[0278] Furthermore, the relationships between the important parameters in the optical lens group 10 of the seventeenth embodiment are as follows: Figure 79 , Figure 80 As shown.

[0279] The longitudinal spherical aberration diagram of this seventeenth embodiment when its pupil radius is 0.6032 mm. Figure 72A In this study, the imaging point deviation of off-axis rays at different altitudes was controlled within ±2.0 micrometers. Figure 72B and Figure 72C In the two field curvature aberration diagrams, the focal length variation for the three representative wavelengths falls within ±4.5 micrometers across the entire field of view. Figure 72D The distortion aberration diagram shows that the distortion aberration of this seventeenth embodiment is maintained within the range of ±3.5%.

[0280] From the above description, it can be seen that: the half-field angle of the seventeenth embodiment is greater than that of the ninth embodiment. The longitudinal spherical aberration of the seventeenth embodiment is less than that of the ninth embodiment. The field curvature of the seventeenth embodiment is less than that of the ninth embodiment. The distortion aberration of the seventeenth embodiment is less than that of the ninth embodiment.

[0281] For the condition EFL / ALT≦2.500, at least one of the purposes is to maintain the system focal length and optical parameters at an appropriate value, avoiding any parameter being too large and thus detrimental to the overall aberration correction of the optical lens group 10, or avoiding any parameter being too small and thus affecting assembly or increasing manufacturing difficulty. The preferred limitation is 1.200≦EFL / ALT≦2.500.

[0282] For values ​​that satisfy (G23+G34+T4) / (T2+T3)≦3.800, (T1+G23+G34+T4) / (T2+T3)≦4.000, (LCR+T1) / (T3+T4)≦1.900, (AAG+BFL) / (T2+T4)≦1.800, LCR / T2≦2.500, TTL / (T2 +T3)≦7.400, TTL / (T2+T3)≦7.400, TL / ALT≦1.900, (T1+G23) / (G12+G34)≦3.5 00, (T1+G23) / T2≦3.000, (T1+G34) / (G12+T2)≦2.500, (T1+G34) / T2≦3.500, (T The conditional expressions 1+T4) / (G12+T3)≦3.500, (T1+T4) / T2≦3.600, (T1+T4) / T3≦4.500, (G34+T4) / (T1+G12)≦2.500, and (G34+T4) / T2≦3.500 are preferably restricted to 1.200≦(G23+G34+T4) / (T2+T3)≦3.800 and 1.800≦(T1+G23+G34+T4) / (T2+T3)≦3.500. 0.600≦(LCR+T1) / (T3+T4)≦1.900, 0.700≦(AAG+BFL) / (T2+T4)≦1.800, 0.900≦LCR / T2≦2.500, 3.000≦TTL / (T2+T3)≦7.400, 3.000≦TTL / (T2+T3)≦7.400, 1.100≦TL / ALT≦1.900 , 0.700≦(T1+G23) / (G12+G34)≦3.500, 1.700≦(T1+G23) / T2≦3.000, 0.700≦(T1+G34) / (G12+T2)≦ 2.500, 1.300≦(T1+G34) / T2≦3.500, 1.300≦(T1+T4) / (G12+T3)≦3.500, 1.700≦(T1+T4) / T2≦3.60 The purpose of at least one of the following parameters is to maintain the thickness and spacing of each lens at an appropriate value, avoiding any parameter being too large, which would be detrimental to the overall thinning of the optical lens group 10, or avoiding any parameter being too small, which would affect assembly or increase the difficulty of manufacturing.

[0283] In addition, any combination of parameters in the alternative embodiments can be selected to increase lens constraints, thereby facilitating the design of optical lens groups with the same architecture as the present invention.

[0284] In view of the unpredictability of optical system design, under the framework of the present invention, meeting the above conditions can better shorten the length of the optical lens group, increase the usable aperture, improve the optical quality, or improve the assembly yield, thereby improving the shortcomings of the prior art.

[0285] The exemplary limiting relationships listed above can be selectively combined and applied in varying numbers to embodiments of the present invention, and are not limited thereto. In implementing the present invention, in addition to the aforementioned relationships, additional detailed structures such as concave-convex surface arrangements of lenses can be designed for a single lens or more broadly for multiple lenses to enhance control over system performance and / or resolution. For example, a convex portion 311 located near the optical axis I can be selectively formed on the light-emitting surface 31 of the first lens 3. It should be noted that these details should be selectively combined and applied to other embodiments of the present invention without conflict.

[0286] In summary, the optical lens group 10 of the embodiments of the present invention can achieve at least the following effects and advantages:

[0287] I. The longitudinal spherical aberration, astigmatism, and distortion in all embodiments of this invention conform to the usage specifications. Furthermore, off-axis light rays of the three representative wavelengths (930nm, 940nm, and 950nm) at different heights are all concentrated near the imaging point. The skewing amplitude of each curve shows that the imaging point deviation of off-axis light rays at different heights is controlled, demonstrating excellent spherical aberration, astigmatism, and distortion suppression capabilities. Further review of the imaging quality data reveals that the distances between the three representative wavelengths (930nm, 940nm, and 950nm) are also quite close, indicating that this invention exhibits excellent dispersion suppression capabilities due to its superior concentration of light rays of different wavelengths under various conditions.

[0288] Second, the first lens 3 has a positive refractive index, and the combination of the convex portion 313 of the light-emitting surface 31 and the concave portion 324 of the light-incident surface 32, and the convex portion 41 of the light-emitting surface 41 of the second lens 4, helps to reduce the degree of beam divergence.

[0289] Third, the area near the circumference of the incident surface 41 of the fourth lens 4 is a convex part 413, which helps to shorten the system length (TTL) while reducing spherical aberration and distortion by using four lenses.

[0290] Fourth, when TTL is ≤ 6mm, it is beneficial to improve yield and apply to larger portable electronic products. The preferred limit is less than 4mm, which is beneficial for applying to smaller portable electronic products.

[0291] Fifth, HFOV ≤ 20° helps to reduce distortion even further. If the angle between the main ray CF of the near-infrared light emitted by the multi-source structured light generation unit 15 and the normal direction D of the light-emitting surface 100a is less than 5°, the degree of beam divergence can be reduced, thereby improving the 3D sensing effect.

[0292] VI. When the condition V1+V2+V3+V4≦141.0 or 2.550≦(n1+n2+n3+n4)-4 is satisfied, the surface shape constraint is beneficial to the use of high refractive index materials, so that the output beam is not easy to diverge with distance or to minimize the degree of divergence and reduce the system length. The preferred constraint is 60.0≦V1+V2+V3+V4≦120.0 or 2.550≦(n1+n2+n3+n4)-4≦3.500.

[0293] 7. In the optical lens group 10 of the present invention, one of the lens materials is glass with a refractive index greater than 1.8, which is beneficial to maintaining a certain optical quality in the heating environment of the multi-source structured light generation unit 15 and reducing the influence of temperature on optical quality. The preferred glass material configuration is the first lens 3 or the fifth lens 7 which is closer to the aperture 2 and has a refractive index.

[0294] The numerical ranges, including the maximum and minimum values, obtained from the combined proportional relationships of the optical parameters disclosed in the various embodiments of the present invention can all be implemented accordingly.

[0295] Although the present invention has been disclosed above by way of embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make some modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. An optical lens assembly for generating multiple beams from multiple near-infrared lights emitted by a multi-source structured light generating unit, wherein the direction toward the multi-source structured light generating unit is an incident light side, and the opposite side is an emitting light side, the optical lens assembly sequentially comprising a first lens, a second lens, a third lens, and a fourth lens along an optical axis from the emitting light side to the incident light side, and each of the first lens, the second lens, the third lens, and the fourth lens includes an emitting light surface toward the emitting light side and an incident light surface toward the incident light side; characterized in that, The first lens is the fourth lens counting from the light-incident side to the light-out side; The second lens is the third lens, measured from the light-incident side to the light-outceasing side; The third lens is the second lens measured from the light-incident side to the light-outceasing side; The fourth lens is the first lens measured from the light-incident side to the light-outceasing side; The optical lens group has a maximum of five lenses; The optical lens group meets the following requirements: LCR / T2≦2.500, and (T1+G23) / (G12+G34)≦3.500 or (G34+T4) / (T1+G12)≦2.500, where T1 is the thickness of the first lens on the optical axis, T2 is the thickness of the second lens on the optical axis, LCR is the radius of the smallest circumcircle of the light-emitting surface of the multi-source structured light generation unit, T4 is the thickness of the fourth lens on the optical axis, G23 is the air gap between the second lens and the third lens on the optical axis, G12 is the air gap between the first lens and the second lens on the optical axis, and G34 is the air gap between the third lens and the fourth lens on the optical axis.

2. An optical lens assembly for generating multiple beams from multiple near-infrared lights emitted by a multi-source structured light generating unit, wherein the direction toward the multi-source structured light generating unit is an incident light side, and the opposite side is an emitting light side, the optical lens assembly sequentially comprising a first lens, a second lens, a third lens, and a fourth lens along an optical axis from the emitting light side to the incident light side, and each of the first lens, the second lens, the third lens, and the fourth lens includes an emitting light surface toward the emitting light side and an incident light surface toward the incident light side; characterized in that, The first lens is the fourth lens counting from the light-incident side to the light-out side; The second lens is the third lens, measured from the light-incident side to the light-outceasing side; The third lens is the second lens measured from the light-incident side to the light-outceasing side; The fourth lens is the first lens measured from the light-incident side to the light-outceasing side; The optical lens group has a maximum of five lenses; The optical lens group meets the following conditions: HFOV≦20°, and (T1+G23) / (G12+G34)≦3.500 or (G34+T4) / (T1+G12)≦2.500, where HFOV is the half field of view of the optical lens group, T1 is the thickness of the first lens on the optical axis, T4 is the thickness of the fourth lens on the optical axis, G23 is the air gap between the second and third lenses on the optical axis, G12 is the air gap between the first and second lenses on the optical axis, and G34 is the air gap between the third and fourth lenses on the optical axis.

3. An optical lens assembly for generating multiple beams from multiple near-infrared lights emitted by a multi-source structured light generating unit, wherein the direction toward the multi-source structured light generating unit is an incident light side, and the opposite side is an emitting light side, the optical lens assembly sequentially comprising a first lens, a second lens, a third lens, and a fourth lens along an optical axis from the emitting light side to the incident light side, and each of the first lens, the second lens, the third lens, and the fourth lens includes an emitting light surface toward the emitting light side and an incident light surface toward the incident light side; characterized in that... The first lens is the fourth lens counting from the light-incident side to the light-out side; The second lens is the third lens, measured from the light-incident side to the light-outceasing side; The third lens is the second lens measured from the light-incident side to the light-outceasing side; The fourth lens is the first lens measured from the light-incident side to the light-outceasing side; The optical lens group has a maximum of five lenses; The optical lens group conforms to: 2.550≦(n1+n2+n3+n4)-4≦3.500, and (T1+G23) / (G12+G34)≦3.500 or (G34+T4) / (T1+G12)≦2.500, where n1 is the refractive index of the first lens, n2 is the refractive index of the second lens, n3 is the refractive index of the third lens, n4 is the refractive index of the fourth lens, T1 is the thickness of the first lens on the optical axis, T4 is the thickness of the fourth lens on the optical axis, G23 is the air gap between the second and third lenses on the optical axis, G12 is the air gap between the first and second lenses on the optical axis, and G34 is the air gap between the third and fourth lenses on the optical axis.

4. An optical lens assembly for generating multiple beams from multiple near-infrared lights emitted by a multi-source structured light generating unit, wherein the direction toward the multi-source structured light generating unit is an incident light side, and the opposite side is an emitting light side, the optical lens assembly sequentially comprising a first lens, a second lens, a third lens, and a fourth lens along an optical axis from the emitting light side to the incident light side, and each of the first lens, the second lens, the third lens, and the fourth lens includes an emitting light surface toward the emitting light side and an incident light surface toward the incident light side; characterized in that, The first lens is the fourth lens counting from the light-incident side to the light-out side; The second lens is the third lens, measured from the light-incident side to the light-outceasing side; The third lens is the second lens measured from the light-incident side to the light-outceasing side; The fourth lens is the first lens measured from the light-incident side to the light-outceasing side; The optical lens group has a maximum of five lenses; The optical lens group conforms to: TL / ALT≦1.900, and (T1+G23) / (G12+G34)≦3.500 or (G34+T4) / (T1+G12)≦2.500, where TL is the distance on the optical axis from the light-emitting surface of the first lens to the light-incident surface of the fourth lens, ALT is the sum of the thicknesses of all lenses with refractive indices on the optical axis, T1 is the thickness of the first lens on the optical axis, T4 is the thickness of the fourth lens on the optical axis, G23 is the air gap on the optical axis between the second and third lenses, G12 is the air gap on the optical axis between the first and second lenses, and G34 is the air gap on the optical axis between the third and fourth lenses.

5. An optical lens assembly for generating multiple beams from multiple near-infrared lights emitted by a multi-source structured light generating unit, wherein the direction toward the multi-source structured light generating unit is an incident light side, and the opposite side is an emitting light side, the optical lens assembly sequentially comprising a first lens, a second lens, a third lens, and a fourth lens along an optical axis from the emitting light side to the incident light side, and each of the first lens, the second lens, the third lens, and the fourth lens includes an emitting light surface toward the emitting light side and an incident light surface toward the incident light side; characterized in that, The first lens is the fourth lens counting from the light-incident side to the light-out side; The second lens is the third lens, measured from the light-incident side to the light-outceasing side; The third lens is the second lens measured from the light-incident side to the light-outceasing side; The fourth lens is the first lens measured from the light-incident side to the light-outceasing side; The optical lens group has a maximum of five lenses; The optical lens group conforms to: TTL / (T2+T3)≦7.400, and (T1+G23) / (G12+G34)≦3.500 or (G34+T4) / (T1+G12)≦2.500, where TTL is the distance from the light-emitting surface of the first lens to the structured light generating unit of the multi-source light source on the optical axis, T1 is the thickness of the first lens on the optical axis, T2 is the thickness of the second lens on the optical axis, T4 is the thickness of the fourth lens on the optical axis, G23 is the air gap between the second lens and the third lens on the optical axis, G12 is the air gap between the first lens and the second lens on the optical axis, and G34 is the air gap between the third lens and the fourth lens on the optical axis.

6. An optical lens assembly for generating multiple beams from multiple near-infrared lights emitted by a multi-source structured light generating unit, wherein the direction toward the multi-source structured light generating unit is an incident light side, and the opposite side is an emitting light side, the optical lens assembly sequentially comprising a first lens, a second lens, a third lens, and a fourth lens along an optical axis from the emitting light side to the incident light side, and each of the first lens, the second lens, the third lens, and the fourth lens includes an emitting light surface toward the emitting light side and an incident light surface toward the incident light side; characterized in that... The first lens is the fourth lens counting from the light-incident side to the light-out side; The second lens is the third lens, measured from the light-incident side to the light-outceasing side; The third lens is the second lens measured from the light-incident side to the light-outceasing side; The fourth lens is the first lens measured from the light-incident side to the light-outceasing side; The optical lens group has a maximum of five lenses; The optical lens group conforms to: (G23+G34+T4) / (T2+T3)≦3.800, and (T1+G23) / (G12+G34)≦3.500 or (G34+T4) / (T1+G12)≦2.500, where T1 is the thickness of the first lens on the optical axis, T2 is the thickness of the second lens on the optical axis, T3 is the thickness of the third lens on the optical axis, T4 is the thickness of the fourth lens on the optical axis, G23 is the air gap between the second lens and the third lens on the optical axis, G12 is the air gap between the first lens and the second lens on the optical axis, and G34 is the air gap between the third lens and the fourth lens on the optical axis.

7. The optical lens assembly according to claim 1, 2, 3, 4, 5 or 6, characterized in that, The distance from the light-emitting surface of the first lens to the structured light generating unit of the multi-source light source on the optical axis is less than or equal to 6 millimeters.

8. The optical lens assembly according to claim 1, 2, 3, 4, 5 or 6, characterized in that, The optical lens group conforms to: V1+V2+V3+V4≦141, where V1 is the Abbe coefficient of the first lens, V2 is the Abbe coefficient of the second lens, V3 is the Abbe coefficient of the third lens, and V4 is the Abbe coefficient of the fourth lens.

9. The optical lens assembly according to claim 1, 2, 3, 4, 5 or 6, characterized in that, The light-emitting surface of the second lens has a convex surface located in the region near the optical axis.

10. The optical lens assembly according to claim 1, 2, 3, 4, 5 or 6, characterized in that, The incident surface of the second lens has a concave portion located in the region near the optical axis.

11. The optical lens assembly according to claim 1, 2, 3, 4, 5 or 6, characterized in that, The light-emitting surface of the second lens has a convex surface located in the area near the circumference.

12. The optical lens assembly according to claim 1, 2, 3, 4, 5 or 6, characterized in that, The incident surface of the fourth lens has a convex portion located in the region near the optical axis.

13. The optical lens assembly according to claim 1, 2, 3, 4, 5 or 6, characterized in that, The thickness of the first lens on the optical axis is less than the thickness of the fourth lens on the optical axis.

14. The optical lens assembly according to claim 1, 2, 3, 4, 5 or 6, characterized in that, The thickness of the second lens on the optical axis is greater than the thickness of the third lens on the optical axis.

15. The optical lens assembly according to claim 1, 2, 3, 4, 5 or 6, characterized in that, The thickness of the third lens on the optical axis is less than the thickness of the fourth lens on the optical axis.

16. The optical lens assembly according to claim 1, 2, 3, 4, 5 or 6, characterized in that, The thickness of the third lens on the optical axis is less than the air gap between the second lens and the third lens on the optical axis.

17. The optical lens assembly according to claim 1, 2, 3, 4, 5 or 6, characterized in that, The thickness of the third lens on the optical axis is less than the air gap between the third lens and the fourth lens on the optical axis.

18. The optical lens assembly according to claim 1, 2, 3, 4, 5 or 6, characterized in that, One of the lenses is made of glass with a refractive index greater than 1.

8.

19. The optical lens assembly according to claim 1, 2, 3, 4, 5 or 6, characterized in that, The first lens is made of glass with a refractive index greater than 1.8.

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