Optical lens and light source device adopting same

Abstract

The invention relates to the technical field of semiconductor light emitting, and discloses an optical lens and a light source device adopting the optical lens. The optical lens comprises a first prism and a second prism which are separated from each other and sequentially arranged from bottom to top. The first prism includes a first optical interface and a second optical interface. The second prism includes a third optical interface and a fourth optical interface. The second optical interface and the third optical interface are close to each other and are correspondingly arranged. The first prism and the second prism are long and narrow lenses, and the central line of the first prism in the long and narrow direction and the central line of the second prism in the long and narrow direction form a certain included angle alpha, 0 degree lt; [alpha] [lt]; and 180 degrees. According to the invention, the first prism and the second prism are arranged in a face shape and are arranged in a crossed manner, so that the light-emitting holes of the array are imaged, each light-emitting hole and the light field form a one-to-one correspondence relationship, and the addressable function is fully realized. In the whole FOV field of view, light control is more accurate, response is faster, and point-to-point, line-to-line and face-to-face control is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of semiconductor light emitting, and in particular, relates to an optical lens and a light source device using the optical lens. Background Art

[0002] With the advent of VCSEL chips, the application of VCSEL chips has expanded from smart hardware to LiDAR. When VCSEL arrays are used as the projection light source of vehicle-mounted LiDAR, when scanning the target, the VCSEL array needs to be lit up in sections to gradually scan the outer surface of the target. From the early single-point VCSEL and single-line VCSEL to the current addressable VCSEL, that is, the light output holes of the surface array, each light output hole or each light output hole emits light separately, which can form a distribution in the area corresponding to the FOV area on the light field, and can correspond one to one.

[0003] The first application solution of addressable VCSEL chips is to use multiple single-point light source devices to display, each pointing in a different direction, and splicing them into a large FOV field of view. In this method, dark areas are easily present at the middle splicing. Although 3D addressability can be achieved, the splicing effect in the large FOV field of view is not good and the brightness distribution is uneven.

[0004] The second addressable application solution of VCSEL chips uses a line laser light source to scan the emitted line light source through the line laser light source to form a large FOV field of view, which can achieve 2D addressability. However, the energy of a single line laser is limited, which is not applicable to long-distance application scenarios and cannot meet the ns-level response speed. Especially for application scenarios like laser radar, faster response speed and longer irradiation distance are required, and the chip's light-emitting holes must correspond one-to-one with the light field pixels. The above two solutions cannot meet the application requirements.

[0005] Based on the above, the problem to be solved at present is: to provide an optical lens and a light source device thereof which are addressable, have a fast response speed, high brightness and uniform light output. Summary of the invention

[0006] The object of the present invention is to provide an optical lens and a light source device using the optical lens, aiming to solve the problems of uneven light emission, low brightness, slow response speed and low accuracy of addressable light sources in the prior art.

[0007] The present invention is realized by an optical lens, comprising a first prism and a second prism separated from each other and arranged in sequence from bottom to top;

[0008] The first prism includes, from bottom to top, a first optical interface for inputting light and a second optical interface for outputting light;

[0009] The second prism includes, from bottom to top, a third optical interface for inputting light and a fourth optical interface for outputting light;

[0010] The second optical interface is disposed close to and corresponding to the third optical interface;

[0011] The first prism is a long and narrow lens formed by the first optical interface and the second optical interface extending left and right, and the second prism is a long and narrow lens formed by the third optical interface and the fourth optical interface extending left and right; the center line of the first prism in its long and narrow direction and the center line of the second prism in its long and narrow direction are arranged at a certain angle α, 0°<α<180°.

[0012] Further, the first optical interface and the third optical interface are free-form surfaces; the contour line of the first optical interface in the XZ plane is a first curve, and the contour line of the third optical interface in the YZ plane is a second curve; the first curve and the second curve are curves protruding toward the outside of the first prism and the second prism respectively;

[0013] The X-axis, Y-axis, and Z-axis are spatial rectangular coordinate axes. The plane formed by the X-axis and Y-axis is defined as the XY plane, the plane formed by the X-axis and Z-axis is defined as the XZ plane, and the plane formed by the Y-axis and Z-axis is defined as the YZ plane.

[0014] Further, the first prism is a cylindrical lens formed by translating the first curve along the Y axis; and the second prism is a cylindrical lens formed by translating the second curve along the X axis.

[0015] Furthermore, the first curve and the second curve are axisymmetric curves respectively.

[0016] Furthermore, a contour line of the first optical interface in the YZ plane is a third curve, and the third curve is a curve convex toward the outside of the first prism.

[0017] Furthermore, the curvature of the third curve is smaller than the curvature of the first curve.

[0018] Furthermore, a contour line of the third optical interface in the XZ plane is a fourth curve, and the fourth curve is a curve recessed toward the inside of the second prism.

[0019] Furthermore, the curvature of the fourth curve is smaller than the curvature of the second curve.

[0020] Furthermore, the lengths of the first prism in the X-axis and Y-axis directions are L1 and L2 respectively, and the lengths of the second prism in the X-axis and Y-axis directions are W1 and W2 respectively, satisfying L1 <W1、L2<W2。

[0021] A light source device includes the optical lens and further includes a light-emitting chip. The light-emitting chip is disposed below the first optical interface, and a plurality of light-emitting holes are provided on the light-emitting chip. The light-emitting holes are distributed in a regular array or randomly.

[0022] Compared with the prior art, the optical lens provided by the present invention and the light source device adopting the optical lens have the following beneficial effects:

[0023] 1. Compared with the optical lens with a conical interface surface type having both a first optical interface and a third optical interface, which is a combination of two separated lenses in the present invention, while ensuring the optical shaping effect in different directions, the present invention has a larger applicable size range of the light-emitting chip, is particularly suitable for the light-emitting chip provided with a plurality of light-emitting holes, has a higher light energy utilization rate at the edge, and realizes addressable light emission.

[0024] 2. The first prism and the second prism intersect the XZ plane and the YZ plane at a first curve and a second curve respectively, and the first curve and the second curve are convex curves. The shapes of the first curve and the second curve are set such that the light in the central region of the light-emitting chip is refracted by the first prism and the second prism corresponding to the central region of the field of view angle; the light in the edge region of the light-emitting chip is refracted by the first prism and the second prism corresponding to the other edge region of the field of view angle. Referring to Figure 8-11 , a one-to-one correspondence relationship is formed between each light-emitting hole and the corresponding region of the light field, and the 3D addressable and 2D addressable functions are fully realized. Within the entire FOV field of view, the light control is more accurate, the response speed is fast, and it better matches the application scenario of the lidar. Point-to-point, line-to-line, and face-to-face control is achieved between the light-emitting chip and the light field, greatly reducing the light-emitting power of the light-emitting chip.

[0025] 3. The size relationships of the light-emitting chip, the first prism, and the second prism of the light source device of the present invention are set as S1 < L1 < W1, S2 < L2 < W2, so that the entire optical lens completely covers the light-emitting chip, ensuring that the edge light of the light-emitting chip is shaped and utilized by the optical lens, improving the light energy utilization rate and brightness uniformity, with high precision and realizing the addressable function. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a schematic three-dimensional structure diagram of the optical lens provided by the present invention;

[0027] Figure 2 is a top view of the first prism provided by the present invention;

[0028] Figure 3 is a top view of the second prism provided by the present invention;

[0029] Figure 4 is a top view of the light-emitting chip provided by the present invention;

[0030] Figure 5 is a cross-sectional view of the optical lens of Example 1 provided by the present invention taken along an XZ plane;

[0031] Figure 6 is a YZ plane cross-sectional view of the optical lens of Example 1 provided by the present invention;

[0032] Figure 7 It is a schematic diagram of the three-dimensional structure of the light source device provided by the present invention;

[0033] Figure 8 It is a light path diagram of the outgoing light from the central area of ​​the light emitting chip of the light source device provided by the present invention in the XZ plane;

[0034] Fig. 9 It is a light path diagram of the outgoing light from the central area of ​​the light emitting chip of the light source device provided by the present invention in the YZ plane;

[0035] Fig.10 It is a light path diagram of the outgoing light in the edge area of ​​the light emitting chip of the light source device provided by the present invention in the XZ plane;

[0036] Fig.11 It is a light path diagram of the outgoing light in the edge area of ​​the light emitting chip of the light source device provided by the present invention in the YZ plane;

[0037] Fig.12 is a schematic diagram of the three-dimensional structure of the first prism of Example 2 provided by the present invention;

[0038] Fig.13 is a top view of a first prism according to Example 2 provided by the present invention;

[0039] Fig.14 is a front view of a first prism in Example 2 provided by the present invention;

[0040] Fig.15 is a left side view of the first prism of Example 2 provided by the present invention;

[0041] Fig.16 is a schematic diagram of the three-dimensional structure of the second prism of Example 3 provided by the present invention;

[0042] Fig.17 is a top view of a second prism according to Example 3 provided by the present invention;

[0043] Fig.18 yes Fig.17 The cross-section diagram in the AA direction;

[0044] Fig.19 yes Fig.17 The cross-sectional view in the BB direction;

[0045] In the figure: 1-first prism; 11-first optical interface; 111-first curve; 112-third curve; 12-second optical interface; 2-second prism; 21-third optical interface; 211-second curve; 212-fourth curve; 22-fourth optical interface; 3-light-emitting chip; 31-light-emitting hole. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0047] The implementation of the present invention is described in detail below in conjunction with specific embodiments.

[0048] The same or similar numbers in the drawings of this embodiment correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the drawings, it is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as limitations on this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0049] Reference Figure 1-19 The figure shows a preferred embodiment of the present invention.

[0050] Reference Figure 1 The optical lens includes a first prism 1 and a second prism 2 which are separated from each other and arranged in sequence from bottom to top. The first prism 1 and the second prism 2 are arranged crosswise. The first prism 1 is a long and narrow lens formed by the first optical interface 11 and the second optical interface 12 extending in a certain direction, and the second prism 2 is a long and narrow lens formed by the third optical interface 21 and the fourth optical interface 22 extending in a certain direction. The center line of the first prism 1 in its long and narrow direction and the center line of the second prism 2 in its long and narrow direction are arranged at a certain angle α, 0°<α<180°, preferably 60°<α<120°. That is, the first prism 1 and the second prism 2 are arranged crosswise.

[0051] The first prism 1 includes a first optical interface 11 for inputting light and a second optical interface 12 for outputting light from bottom to top. The second prism 2 includes a third optical interface 21 for inputting light and a fourth optical interface 22 for outputting light from bottom to top. The incident light enters the second prism 2 after being refracted by the first prism 1, and then exits through the refraction of the second prism 2. The first optical interface 11 and the third optical interface 21 are free-form surfaces. The second optical interface 12 and the third optical interface 21 are arranged close to and corresponding to each other. The input light enters the first optical interface 11, and exits from the second optical interface 12 after being refracted. The exiting light of the first prism 1 enters the third optical interface 21 and is refracted, and then exits from the fourth optical interface 22. Compared with an optical lens with a conical interface having both the first optical interface and the third optical interface, the combination of two separate lenses of the present invention can increase the size of the applicable light-emitting chip while ensuring the optical shaping effect in different directions, and the light energy utilization rate at the edge is higher, so that the addressable light emission is realized.

[0052] The X-axis, Y-axis, and Z-axis are the spatial rectangular coordinate axes. The plane formed by the X-axis and Y-axis is the XY plane, the plane formed by the X-axis and Z-axis is the XZ plane, and the plane formed by the Y-axis and Z-axis is the YZ plane. Figure 5 The projection of the first optical interface 11 on the XZ plane is a first curve 111. Figure 6 , the projection of the third optical interface 21 on the YZ plane is the second curve 211. The first curve 111 is a curve convex to the outside of the first prism 1, and the second curve 211 is a curve convex to the outside of the second prism 2. The curvatures of the first curve 111 and the second curve 211 are relatively large. Preferably, the first curve 111 and the second curve 211 are axisymmetric curves, respectively.

[0053] Reference Figure 8-9 , the light emitted from the light-emitting hole 31 in the central area of ​​the light-emitting chip 3 is distributed in the central area of ​​the field of view after being optically shaped by the first prism 1 and the second prism 2; Figure 10-11 , the light emitted from the light-emitting hole 31 in the edge area of ​​the light-emitting chip 3 is optically shaped by the first prism 1 and the second prism 2 and then mirrored to the edge area of ​​the field of view angle, so that the light-emitting holes 31 at different positions correspond to different field of view angle positions. The optical lens of the present invention images the VCSEL light-emitting holes 31 of the array through the setting and cross-placement of the first prism and the second prism surface shape, so that each light-emitting hole 31 forms a one-to-one correspondence with the light field, fully realizing the 3D addressable and 2D addressable functions. Within the entire FOV field of view, light control is more precise and better matches the application scenarios of the laser radar, realizing point-to-point, line-to-line, and face-to-face control.

[0054] Further, see Figure 2, the lengths of the first prism 1 in the X-axis and Y-axis directions are L1 and L2, respectively, and L2> L1. Figure 3 , the lengths of the second prism 2 in the X-axis and Y-axis directions are W1 and W2 respectively, W2<W1. W2>L2, W1>L1 are satisfied. The curvature of the first curve 111 is greater than the curvature of the second curve 211. In order to achieve a larger FOV of the light field and the need for addressing the light-emitting hole 31 of the light-emitting chip 3, the edge incident light is refracted at a large angle, so the first curve 111 and the second curve 211 are set with a larger curvature, that is, the curves are steeper. In this way, the length L1 of the first prism 1 on the X-axis and the length W2 of the second prism 2 on the Y-axis are relatively small. When the light-emitting chip 3 is large, in order to ensure that all the light from the edges is irradiated onto the optical lens, the length L2 of the first prism 1 on the Y-axis and the length W1 of the second prism 2 on the X-axis are set to be large. Because the first prism 1 and the second prism 2 are placed crosswise, they are sufficient to cover the light-emitting chip 3, so that the incident light can be deflected at a large angle in the XZ plane and the YZ plane respectively through the separated first prism 1 and the second prism 2, while ensuring that the edge light can be fully utilized, thereby improving the utilization rate of light energy and achieving the purpose of addressing the light-emitting holes 31 of the light-emitting chip 3 one by one, achieving full addressability, high light energy utilization rate, high accuracy and fast impact speed.

[0055] Example 1: Reference Figure 1 The first prism 1 is a cylindrical lens formed by translating the first curve 111 along the Y axis. The second prism 2 is a cylindrical lens formed by translating the second curve 211 along the X axis. The projection (or contour line) of the first prism 1 on the YZ plane is a rectangle. The projection (or contour line) of the second prism 2 on the XZ plane is a rectangle.

[0056] Example 2: Reference Figure 12-15 The projection of the first optical interface 11 on the YZ plane is a third curve 112, and the third curve 112 is a curve protruding toward the outside of the first prism 1. The third curve 112 is used to preliminarily refract the light incident to the first prism 1 on the YZ plane, and the light emitted from the first prism 1 enters the second prism 2 for further large-angle refraction. This setting can be used to further adjust the deflection angle of the second prism 2 in the YZ direction. The curvature of the third curve 112 is smaller than the curvature of the first curve 111. Preferably, the third curve 112 is an axisymmetric curve.

[0057] Example 3: Reference Figure 16-19 The projection of the third optical interface 21 on the XZ plane is a fourth curve 212, and the fourth curve 212 is a curve that is concave toward the inside of the second prism 2. The fourth curve 212 is provided for the second prism 2 to further optically shape the outgoing light of the first prism 1 in a parallel XZ plane to meet the needs of the application scenario. The curvature of the fourth curve 212 is less than the curvature of the second curve 211. The third interface 21 is a saddle surface or a saddle-like surface.

[0058] Further, the second optical interface 12 and the fourth optical interface 22 can be respectively set as a plane or a free-form surface and adjusted according to the requirements of the application scenario.

[0059] A light source device, referring to Figure 7 , includes an optical lens and a light-emitting chip 3. The light-emitting chip 3 is disposed below the first optical interface 11. The light-emitting chip 3 is rectangular. Preferably, the adjacent sides of the rectangle are respectively placed parallel to the X-axis and Y-axis directions, and their lengths are S1 and S2 respectively, referring to Figure 4 . Preferably, the dimensional relationship among the light-emitting chip 3, the first prism 1 and the second prism 2 of the light source device satisfies S1 < L1 < W1, S2 < L2 < W2. The entire optical lens completely covers the light-emitting chip 3, ensuring that the edge light of the light-emitting chip 3 is shaped and utilized by the optical lens, improving the light energy utilization rate and brightness uniformity, and realizing the addressable function. The light-emitting chip 3 is preferably a VCSEL light-emitting chip. A plurality of light-emitting holes 31 are provided on the light-emitting chip 3. The light-emitting holes 31 are distributed in a regular array or randomly, preferably in a regular array. When a single light-emitting hole 31 or a row or a column of light-emitting holes 31 of the light-emitting chip 3 is lit, a light field can be formed in a specified field of view area after the action of the optical lens of the present invention, that is, each light-emitting hole 31 forms a one-to-one correspondence with the corresponding area of the light field, fully realizing the 3D addressable and 2D addressable functions. Within the entire FOV field of view, the light control is more accurate and more suitable for the application scenario of lidar, realizing point-to-point, line-to-line, and face-to-face control.

[0060] The present invention is not limited thereto. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An optical lens, characterized in that: It comprises a first prism (1) and a second prism (2) which are separated from each other and arranged in sequence from bottom to top; The first prism (1) comprises, from bottom to top, a first optical interface (11) for inputting light and a second optical interface (12) for outputting light; The second prism (2) comprises, from bottom to top, a third optical interface (21) for inputting light and a fourth optical interface (22) for outputting light; The second optical interface (12) and the third optical interface (21) are arranged close to and corresponding to each other; The first prism (1) is a long and narrow lens formed by the first optical interface (11) and the second optical interface (12) extending left and right, and the second prism (2) is a long and narrow lens formed by the third optical interface (21) and the fourth optical interface (22) extending left and right; the center line of the first prism (1) in its long and narrow direction and the center line of the second prism (2) in its long and narrow direction are arranged at a certain angle α, 0°<α<180°.

2. The optical lens according to claim 1, wherein: The first optical interface (11) and the third optical interface (21) are free-form surfaces; the contour line of the first optical interface (11) in the XZ plane is a first curve (111), and the contour line of the third optical interface (21) in the YZ plane is a second curve (211); the first curve (111) and the second curve (211) are curves protruding toward the outside of the first prism (1) and the second prism (2), respectively; The X-axis, Y-axis, and Z-axis are spatial rectangular coordinate axes. The plane formed by the X-axis and Y-axis is defined as the XY plane, the plane formed by the X-axis and Z-axis is defined as the XZ plane, and the plane formed by the Y-axis and Z-axis is defined as the YZ plane.

3. The optical lens according to claim 2, wherein: The first prism (1) is a cylindrical lens formed by translating the first curve (111) along the Y axis; the second prism (2) is a cylindrical lens formed by translating the second curve (211) along the X axis.

4. The optical lens according to claim 2, wherein: The first curve (111) and the second curve (211) are respectively axisymmetric curves.

5. The optical lens according to claim 2, wherein: The contour line of the first optical interface (11) in the YZ plane is a third curve (112), and the third curve (112) is a curve that bulges toward the outside of the first prism (1).

6. The optical lens according to claim 5, wherein: The curvature of the third curve (112) is smaller than the curvature of the first curve (111).

7. The optical lens according to claim 2, wherein: The contour line of the third optical interface (21) in the XZ plane is a fourth curve (212), and the fourth curve (212) is a curve that is concave toward the inside of the second prism (2).

8. The optical lens according to claim 7, wherein: The curvature of the fourth curve (212) is smaller than the curvature of the second curve (211).

9. A light source device, characterized in that: The optical lens comprises any one of claims 1 to 8, and further comprises a light-emitting chip (3), wherein the light-emitting chip (3) is arranged below the first optical interface (11), and a plurality of light-emitting holes (31) are arranged on the light-emitting chip (3), and the light-emitting holes (31) are distributed in a regular array or randomly.

10. The light source device according to claim 9, characterized in that: The lengths of the first prism (1) in the X-axis and Y-axis directions are L1 and L2 respectively, the lengths of the second prism (2) in the X-axis and Y-axis directions are W1 and W2 respectively, and the lengths of the light-emitting chip (3) in the X-axis and Y-axis directions are S1 and S2 respectively, satisfying S1 <L1<W1、S2<L2<W2。

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