Method for eliminating crosstalk in partitioned uniform lighting system and uniform lighting system

Abstract

The present invention provides a method for eliminating crosstalk in a partitioned uniform light illumination system, wherein the partitioned uniform light illumination system comprises a light source having a plurality of light source partitions and a diffractive optical element having a plurality of DOE partitions respectively corresponding to the plurality of light source partitions, the light source partitions illuminate the corresponding DOE partitions and project a target light field on the target surface, the light source partitions eccentrically illuminate the DOE partitions adjacent to the corresponding DOE partitions and project a crosstalk light field on the target surface, the method for eliminating crosstalk comprises: S101: determining a specific point of the target light field and a point of the crosstalk light field corresponding to the specific point; and S102: determining the distance between the diffractive optical element and the light source, so that the specific point of the target light field and the corresponding point of the crosstalk light field coincide on the target surface. The preferred embodiment of the present invention reduces the crosstalk of the target light field by precisely controlling and adjusting when assembling the diffractive optical element, and can project a clear uniform light field with a large field of view.

Description

Technical Field

[0001] The present invention generally relates to the field of laser display technology, and in particular to a method for eliminating crosstalk in a zoned uniform light illumination system and a uniform light illumination system. Background Art

[0002] The current TOF (Time-Of-Flight) solution in the mobile phone industry is an indirect time-of-flight solution, which uses indirect time-of-flight, such as the phase change of the emitted light field and the received light field, to calculate the distance of the target object. Compared with the direct time-of-flight ranging of the time-of-flight, the indirect measurement has a large error. For example, when testing multiple targets, it will be converted into an average value to calculate a distance, and the indirect measurement is greatly affected by environmental noise. Directly using timestamps for time-of-flight ranging can solve these problems. Sensors designed for the direct time-of-flight solution need to achieve uniform illumination of the target light field in different zones. In addition, in many other specific application scenarios, it is also necessary to provide a uniformly distributed light field within a certain range.

[0003] Vertical Cavity Surface Emitting Laser (VCSEL) is a widely used laser. The homogenizer of some diffractive optical elements (DOE) is used to homogenize the light field emitted by the entire VCSEL chip. The partition design of the diffractive optical element (DOE) can be performed according to the partition of the VCSEL chip. In actual working scenarios, there is a certain distance between the VCSEL partition light source and the diffractive optical element (DOE). Due to the diffusion effect of the light spot, when the light source spot is irradiated on different DOE partitions, different light fields will be projected in the target area, thus affecting the reconstruction of 3D information.

[0004] The contents of the background technology section are merely the technologies known to the public and do not necessarily represent the existing technologies in the field. Summary of the invention

[0005] In view of at least one defect of the prior art, the present invention provides a method for eliminating crosstalk in a partitioned uniform light illumination system, wherein the partitioned uniform light illumination system comprises a light source having a plurality of light source partitions and a diffractive optical element having a plurality of DOE partitions corresponding to the plurality of light source partitions, the light source partitions illuminate the corresponding DOE partitions and project a target light field on a target surface, the light source partitions eccentrically illuminate the DOE partitions adjacent to the corresponding DOE partitions and project a crosstalk light field on the target surface, and the method for eliminating crosstalk comprises:

[0006] S101: Determine a specific point of the target light field and a point of the crosstalk light field corresponding to the specific point; and

[0007] S102: Determine the distance between the diffractive optical element and the light source so that a specific point of the target light field coincides with a corresponding point of the crosstalk light field on a target surface.

[0008] According to one aspect of the present invention, the specific point of the target light field includes one or more of: a point at the upper edge of the target light field in the vertical direction, a point at the upper and lower edges of the target light field in the vertical direction, and a center point of the target light field in the vertical direction.

[0009] According to one aspect of the present invention, the method for eliminating crosstalk further includes:

[0010] Repeating steps S101 and S102 to determine a plurality of specific points of the target light field and a plurality of corresponding distances;

[0011] A preset distance interval is determined according to the multiple distances, and the distance from the diffractive optical element to the light source is adjusted within the preset distance interval so that the crosstalk light field substantially coincides with the target light field.

[0012] According to one aspect of the present invention, the method for eliminating crosstalk further includes:

[0013] For a plurality of crosstalk light fields projected on the target surface by eccentrically irradiating a plurality of DOE partitions adjacent to the corresponding DOE partition by the light source partition, repeating steps S101 and S102 to determine a specific point of the target light field and a plurality of corresponding distances;

[0014] A preset distance interval is determined according to the multiple distances, and the distance from the diffractive optical element to the light source is adjusted within the preset distance interval so that the crosstalk light field substantially coincides with the target light field.

[0015] According to one aspect of the present invention, the DOE partition of the diffractive optical element includes a microstructure surface, and the microstructure surface includes at least one microstructure pattern unit. The microstructure pattern unit is designed according to the light source parameters of the light source partition corresponding to the DOE partition and the corresponding projected target light field.

[0016] According to one aspect of the present invention, the multiple target light fields are strip-shaped light fields, which are spliced ​​to form a uniform illumination light field.

[0017] The present invention also provides a uniform light illumination system, which uses the method described above to eliminate crosstalk.

[0018] The present invention also provides an electronic device, comprising the uniform light illumination system as described above.

[0019] The preferred embodiment of the present invention provides a method for eliminating crosstalk in a partitioned uniform light illumination system, by adjusting the distance between the VCSEL partitioned light source and the diffractive optical element, so that specific points in part of the target light field coincide with corresponding points in the crosstalk light field, and the adjustment interval of the distance between the VCSEL partitioned light source and the diffractive optical element is obtained by multi-point calculation and multi-partition calculation, and then the optimal light field effect within the adjustment interval is obtained by simulation. The preferred embodiment of the present invention reduces the crosstalk of the target light field by precisely controlling and adjusting when assembling the diffractive optical element, and can project a clear uniform light field with a large field of view. The adjustment method provided by the present invention is applied to the partitioned uniform light illumination system, which provides technical support for the uniform light illumination required by the DTOF system. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0021] Figure 1 A zoned uniform light illumination system according to a preferred embodiment of the present invention is schematically shown;

[0022] Figure 2 Schematically shows a VCSEL partitioned light source according to a preferred embodiment of the present invention;

[0023] Figure 3A The homogenized light field according to a preferred embodiment of the present invention is schematically shown;

[0024] Figure 3B The schematic diagram shows a preferred embodiment of the present invention. Figure 3A The uniform light field shown is divided into a plurality of strip-shaped light fields;

[0025] Figure 4 Schematically shows a diffractive optical element and its partitions according to a preferred embodiment of the present invention;

[0026] Figure 5 A method for eliminating crosstalk in a zoned uniform lighting system according to a preferred embodiment of the present invention is shown;

[0027] Figure 6 A subarea uniform light illumination system having two light source arrays and a target light field and a crosstalk light field generated by the system are schematically shown according to a preferred embodiment of the present invention;

[0028] Fig. 7A , Figure 7B The schematic diagram shows the visual effects of a part of the target light field and the crosstalk light field on the target surface when the distance between the VCSEL partitioned light source and the diffractive optical element is not adjusted;

[0029] Fig. 8A , Figure 8B The diagram schematically shows the visual effects of a portion of the target light field and the crosstalk light field on the target surface after adjusting the distance between the VCSEL partitioned light source and the diffractive optical element according to a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0030] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the present invention. Therefore, the drawings and descriptions are considered to be exemplary and non-restrictive in nature.

[0031] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, which are 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 orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0032] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or can communicate with each other; it can be directly connected, or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply means that the first feature is lower in level than the second feature.

[0034] The disclosure below provides many different embodiments or examples to realize different structures of the present invention. In order to simplify the disclosure of the present invention, the parts and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present invention. In addition, the present invention can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplicity and clarity, which itself does not indicate the relationship between the various embodiments and / or settings discussed. In addition, the present invention provides various specific examples of processes and materials, but those of ordinary skill in the art can be aware of the application of other processes and / or the use of other materials.

[0035] The embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0036] like Figure 1 As shown, the preferred embodiment of the present invention is applied to a partitioned light uniformity projection system 100, which includes a diffractive optical element 10 and a partitioned light source 20, wherein the partitioned light source 20 includes a plurality of light source arrays (refer to Figure 2 ), the plurality of light source arrays are spaced apart along the first direction. The diffractive optical element 10 is disposed downstream of the optical path of the partitioned light source 20, and can receive the light beams emitted by the plurality of light source arrays and project a uniform light field on the target surface OB. d is the distance between the partitioned light source 20 and the diffractive optical element 10, and z is the distance between the diffractive optical element 10 and the target plane OB (i.e., the working distance), wherein the working distance z is a system parameter.

[0037] like Figure 2 As shown, a preferred embodiment of the present invention preferably adopts a vertical cavity surface emitting laser (VCSEL) partitioned light source 20, and the VCSEL partitioned light source 20 includes a plurality of light source arrays 20-1, 20-2, ..., 20-n, wherein, for example due to process limitations, there is a gap between adjacent light source arrays, and there is a certain gap DS between the light source arrays in the first direction (horizontal direction in the figure).

[0038] like Figure 2 As shown, each white dot inside each light source array represents a VCSEL light-emitting point, and the interval between adjacent VCSEL light-emitting points is small, while the interval DS between adjacent light source arrays is usually large, which is greater than the distance between VCSEL light-emitting points in the same light source array. In order to cooperate with the work of the DTOF sensor, it is necessary to realize the partitioned uniform illumination of the target light field, that is, each light source array of the VCSEL partitioned light source can be illuminated separately, and when each light source array is illuminated, only the part of the target light field corresponding to the light source array is uniformly illuminated, and it is necessary to ensure the uniform illumination of the entire target light field when all light source arrays are illuminated.

[0039] Figure 3A Figure 2 shows the uniform light field required for the DTOF sensor. Figure 3A The uniform light field shown is divided according to the projection area of ​​the multiple light source arrays of the VCSEL partition light source 20, and is divided into the following Figure 3B When each light source array of the VCSEL partitioned light source 20 is lit individually, the uniform light illuminates a corresponding strip light field; when all light source arrays are lit, multiple strip light fields are spliced ​​to form the target light field of the diffractive optical element.

[0040] like Figure 4 As shown, the diffractive optical element 10 has multiple partitions, and multiple microstructure pattern units with the same number in the figure constitute a DOE partition, such as multiple microstructure pattern units labeled "1" constitute a DOE partition... multiple microstructure pattern units labeled "6" constitute a DOE partition... multiple microstructure pattern units labeled "n" constitute a DOE partition. Each DOE partition corresponds to Figure 2 In the illustrated VCSEL partitioned light source 20, a plurality of microstructure pattern units labeled "1" constitute a DOE partition, corresponding to a light source array 20-1 of the VCSEL partitioned light source 20... a plurality of microstructure pattern units labeled "6" constitute a DOE partition, corresponding to a light source array 20-6 of the VCSEL partitioned light source 20... a plurality of microstructure pattern units labeled "n" constitute a DOE partition, corresponding to a light source array 20-n of the VCSEL partitioned light source 20. Each DOE partition corresponds to Figure 2 A light source array of the VCSEL partitioned light source shown in the figure corresponds to a partial light field in the target light field projected by the light source array.

[0041] In actual operation, the VCSEL partitioned light source 20 is at a certain distance d from the diffractive optical element 10, and the single point light source irradiates the diffractive optical element 10 to form a circle with a radius of r. Figure 4As shown, the size of the single-point spot generated by the single-point light source in the VCSEL partitioned light source will be larger than the size of the microstructure pattern unit of the diffractive optical element. When the single-point light source is irradiated on the diffractive optical element 10, the light emitted by it will not only be incident on the DOE partition corresponding to its light source partition, but will also cover other DOE partitions adjacent to the DOE partition, thereby causing crosstalk.

[0042] like Figure 4 As shown in , the single point light source is irradiating the microstructure pattern unit labeled 6, but at the same time, it is eccentrically irradiating the microstructure pattern units labeled 5 and 7. The microstructure pattern unit labeled 6 corresponds to Figure 2 In the light source array 20-6 of the VCSEL partitioned light source 20, the microstructure pattern units numbered 5 and 7 correspond to the light source arrays 20-5 and 20-7 of the VCSEL partitioned light source 20, respectively. That is, the phase distribution of the microstructure pattern unit numbered 6 is designed according to the light source array 20-6 and the corresponding strip light field, and the phase distribution of the microstructure pattern units numbered 5 and 7 are designed according to the light source arrays 20-5 and 20-7 and the corresponding strip light field, respectively. Therefore, the light source array 20-6 of the VCSEL partitioned light source 20 is directly irradiated on the microstructure pattern unit numbered 6, projecting part of the target light field, and eccentrically irradiated on the microstructure pattern units numbered 5 and 7, projecting a crosstalk light field, as shown in FIG. Fig. 7A , Figure 7B As shown, the crosstalk light field T2 is located near a portion of the target light field S1, and the crosstalk light field T1 is located near a portion of the target light field S2, and the crosstalk light field interferes with the target light field.

[0043] According to a preferred embodiment of the present invention, Figure 5 As shown, the present invention provides a method 30 for eliminating crosstalk for a partitioned uniform light illumination system, comprising steps S301 and S302. The partitioned uniform light illumination system 100 comprises a VCSEL partitioned light source 20 having a plurality of light source arrays as described above and a diffractive optical element 10 having a plurality of DOE partitions corresponding to the plurality of light source arrays.

[0044] refer to Figure 6 First, consider the case where the VCSEL partition light source 20 has two light source arrays 20-1 and 20-2. Assume that the center distance between the two light source arrays is L1, and the distance between the diffractive optical element 10 and the VCSEL partition light source 20 is d. According to the division method described above, the diffractive optical element is correspondingly divided into two DOE partitions, such as DOE1 and DOE2 shown in the figure.

[0045] The working distance of the diffractive optical element 10 is z, and the partitioned DOE1 of the diffractive optical element 10 designs the phase distribution for the light source array 20-1 of the VCSEL partitioned light source 20, and forms a light field S1 at the distance z; the partitioned DOE2 of the diffractive optical element 10 designs the phase distribution for the light source array 20-2 of the VCSEL partitioned light source 20, and forms a light field S2 at the distance z.

[0046] During the projection operation of the diffractive optical element 10, the relative position relationship between the working area and the projected light field area conforms to the lens principle. Figure 6 As shown in the positional relationship, the light source array 20-1 of the VCSEL partitioned light source 20 is located above the light source array 20-2, the partitioned DOE1 of the diffractive optical element 10 corresponds to the light source array 20-1, and the partitioned DOE2 corresponds to the light source array 20-2, and DOE1 is located above DOE2. Then, the light field S1 generated by the light source array 20-1 irradiating the partitioned DOE1 is located below the light field S2 generated by the light source array 20-2 irradiating the partitioned DOE2.

[0047] When the distance d between the VCSEL partitioned light source 20 and the diffractive optical element 10 is controlled so that all single point light sources of the light source array 20-1 or the light source array 20-2 are respectively irradiated only on the microstructure pattern unit of the partitioned DOE1 or the partitioned DOE2, no crosstalk will be generated at this time. However, in this case, the distance d is very small, and the effective area of ​​the diffractive optical element 10 is very small. When the pixel size of the diffractive optical element 10 is constant, the number of pixels will be reduced, resulting in a decrease in the modulation ability of the light field, severe speckle of the target light field, and an uneven visual effect of the target light field, which affects the use. Increasing the distance d between the VCSEL partitioned light source 20 and the diffractive optical element 10 allows the VCSEL partitioned light source 20 to irradiate a larger effective area, thereby weakening the speckle and homogenizing the light field. However, at this time, the single point light source of the light source array 20-1 will irradiate on the partitioned DOE2 to form the light field T2, and the single point light source of the light source array 20-2 will irradiate on the partitioned DOE1 to form the light field T1 (not shown), so crosstalk will be generated.

[0048] The distance L2 that the crosstalk light field T2 deviates from the partial target light field S2 is related to the distance L1 between the light source arrays 20-1 and 20-2 of the VCSEL partition light source 20, the distance d from the VCSEL partition light source 20 to the diffractive optical element 10, and the field of view angle or position of the crosstalk light field T2, and can be calculated. To eliminate crosstalk, these parameters should be adjusted so that the crosstalk light field T2 overlaps with the partial target light field S1 as much as possible. Among these parameters, the distance d can be accurately controlled and adjusted when the diffractive optical element 10 is assembled. Therefore, the crosstalk between each block can be minimized by optimizing the distance d during design. Controlling the crosstalk light field T2 to roughly overlap with the partial target light field S1 can be accomplished by making specific points in the partial target light field S1 overlap with corresponding points in the crosstalk light field T2.

[0049] According to a preferred embodiment of the present invention, a method 30 for eliminating crosstalk in a zoned uniform lighting system 100 includes:

[0050] In step S301, a specific point of the target light field and a point of the crosstalk light field corresponding to the specific point are determined.

[0051] Preferably, several special points can be taken, for example, the top point in the vertical direction, the center point in the vertical direction, and the bottom point in the vertical direction of the partial target light field S1; and the points in the crosstalk light field T2 corresponding to these specific points are determined, that is, the top point in the vertical direction, the center point in the vertical direction, and the bottom point in the vertical direction of the crosstalk light field T2.

[0052] In step S102 , the distance d between the VCSEL subarea light source 20 and the diffractive optical element 10 is determined so that a specific point in the partial target light field coincides with a corresponding point in the crosstalk light field on the target surface.

[0053] That is, the distance and related variables between a specific point in the partial target light field S1 and a corresponding point in the crosstalk light field T2 are calculated, and the specific point in the target light field S1 is made to coincide with the corresponding point in the crosstalk light field T2 by adjusting the related variables.

[0054] First, if Figure 6As shown, the crosstalk light field T2 is formed by the light source array 20-1 of the VCSEL partitioned light source 20 eccentrically irradiating the partitioned DOE2 of the diffractive optical element 10, while the light source array 20-2 is irradiating the partitioned DOE2 to form the partial target light field S2. Therefore, the crosstalk light field T2 is equivalent to the light field projected after the light source array moves a distance of L1, and the distance L2 from a specific point in the partial target light field S2 to the corresponding point in the crosstalk light field T2 can be calculated, that is, the moving distance L2 of the specific point is calculated according to the moving distance L1 of the light source array, the distance d from the VCSEL partitioned light source 20 to the diffractive optical element 10, and the field of view angle of the crosstalk light field T2. The distance between the specific point in the partial target light field S2 and the specific point in the partial target light field S1 is easy to obtain. When the width of the partial target light field, that is, the strip light field, is determined, the distance between the specific point in the partial target light field S2 and the specific point in the partial target light field S1 is equal to the width of the strip light field.

[0055] Assume that the light source array 20-2 of the VCSEL partitioned light source 20 irradiates a specific point in the partial target light field S2 generated on the partitioned DOE2 of the diffractive optical element 10, and let the coordinates of the specific point be (x, y). The coordinates of the corresponding point in the crosstalk light field T2 generated by the light source array 20-1 of the VCSEL partitioned light source 20 eccentrically irradiating on the partitioned DOE2 of the diffractive optical element 10 are (x′, y′). Assume that the distance expression between the specific point in the partial target light field S2 and the corresponding point in the crosstalk light field T2 is: L2(L 2,X , L 2,Y ), where L 2,X is the distance in the x direction, L 2,Y is the distance in the y direction, then

[0056] L 2,x =x′-x,L 2,y =y′-y (1)

[0057] The system magnification of the partitioned uniform light illumination system 100 is: Where d is the distance from the VCSEL partitioned light source 20 to the diffractive optical element 10, and z is the distance from the diffractive optical element 10 to the target surface, i.e., the working distance. The light source array 20-1 of the VCSEL partitioned light source 20 eccentrically illuminates the partitioned DOE2 of the diffractive optical element 10, which is equivalent to the light source array 20-2 corresponding to the partitioned DOE2 of the diffractive optical element 10 moving in the direction of the light source array 20-1. Assume that the light source moving distance is (L 1,x , L 1,y ), where L 1,X is the distance moved in the x direction, L 1,Y is the distance moved in the y direction.

[0058] The field of view angle θ of a point (x, y) on the partial target light field S2 in the plane coordinate system is:

[0059]

[0060]

[0061] According to the system magnification α, the coordinates (x1, y1) of the corresponding point on the crosstalk light field T2 in the spherical coordinate system and its field of view angle θ1 are calculated:

[0062] x1=x cosθ+αL 1,x ,

[0063] y1=y cosθ+αL 1,y

[0064]

[0065]

[0066] Then transform the coordinates of the point in the spherical coordinate system to the plane coordinate system:

[0067] x′=x1 / cosθ1, y′=y1 / cosθ1

[0068] Substituting into (1) we get

[0069]

[0070]

[0071] L2(L 2,X , L 2,Y ) is converted into the distance between the specific point on the partial target light field S1 and the corresponding point on the crosstalk light field T2. By adjusting the d value, the above two points are made to coincide with each other, thereby calculating the distance d from the VCSEL partition light source 20 to the diffractive optical element 10.

[0072] The two light source arrays 20-1 and 20-2 of the VCSEL partition light source 20 are arranged along the vertical direction in the figure. Correspondingly, the two DOE partitions DOE1 and DOE2 of the diffractive optical element 10 are also arranged along the vertical direction in the figure. The projected strip light fields S1 and S2 are arranged along the vertical direction in the figure, and the partial target light field S1 is located below the partial target light field S2. The crosstalk light field T2 partially overlaps with the partial target light field S1 and is located below the partial target light field S1. Fig. 7AAs shown, in actual operation, the two light source arrays 20-1 and 20-2 of the VCSEL partition light source 20 are usually arranged in the horizontal direction (for example, from right to left), and correspondingly, the two DOE partitions DOE1 and DOE2 of the diffractive optical element 10 are also arranged in the horizontal direction, and the projected strip light fields S1 and S2 are arranged in the horizontal direction, and the partial target light field S1 is located on the right side of the partial target light field S2, and the crosstalk light field T2 partially overlaps with the partial target light field S1 and is located on the right side of the partial target light field S1.

[0073] Among them, since the crosstalk light field T2 is the light field formed by the eccentric projection of the light source array 20-1, its light field area is slightly larger than the light field S1 formed by the central projection of the light source array. Therefore, in order to make different specific points overlap, different d values ​​can be calculated.

[0074] According to a preferred embodiment of the present invention, the method 30 for eliminating crosstalk in a zoned uniform lighting system provided by the present invention further comprises:

[0075] Repeat the above steps S301 and S302 to determine a plurality of specific points of the target light field and a plurality of corresponding distances d;

[0076] A preset distance interval is determined according to the multiple distances d, and the distance from the diffractive optical element to the light source is adjusted within the preset distance interval so that the crosstalk light field and the target light field substantially coincide with each other. That is, the minimum and maximum values ​​of the d value obtained by the above calculation can be selected within the minimum and maximum value interval.

[0077] According to a preferred embodiment of the present invention, the method 30 for eliminating crosstalk in a zoned uniform lighting system provided by the present invention further comprises:

[0078] For a plurality of crosstalk light fields projected on the target surface by eccentrically irradiating a plurality of DOE partitions adjacent to the corresponding DOE partition by the light source partition, repeating steps S101 and S102 to determine a specific point of the target light field and a plurality of corresponding distances;

[0079] A preset distance interval is determined according to the multiple distances, and the distance from the diffractive optical element to the light source is adjusted within the preset distance interval so that the crosstalk light field substantially coincides with the target light field.

[0080] The above preferred embodiment only discusses the case where crosstalk occurs between two DOE partitions. When crosstalk occurs between more DOE partitions, different d values ​​can be calculated and the range of d values ​​can be determined by analogy.

[0081] According to a preferred embodiment of the present invention, d values ​​are calculated for different specific points on the same DOE partition, and / or d values ​​are calculated for different specific points on multiple DOE partitions to obtain a set of d values. The actual effect diagram of the target light field is simulated through simulation software, and the actual effect of the simulated light field is used as a reference for selecting the d value interval.

[0082] According to a preferred embodiment of the present invention, the specific point of the target light field includes: one or more of the point on the upper edge of the target light field in the vertical direction, the point on the upper and lower edges of the target light field in the vertical direction, and the center point of the target light field in the vertical direction. The point selection method in the above preferred embodiment intuitively illustrates the method of calculating the d value. However, any point on a part of the target light field and its corresponding point on the crosstalk light field can be used to calculate the d value, and the best target light field effect can be obtained through simulation calculation. These are all within the protection scope of the present invention.

[0083] According to a preferred embodiment of the present invention, the target light field is a uniform light field of 16°x60°, the VCSEL partition light source has two light source arrays, the light field is divided into two partitions, and each light field range is 8°x60. The wavelength of the VCSEL sub-light source is 940nm, the divergence angle is 20°, and the working distance z is 1000mm. When the crosstalk elimination process is not performed, the distance d between the VCSEL partition light source 20 and the diffractive optical element 10 is 1mm, and the simulation effect of the light field is as follows: Fig. 7A , Figure 7B As shown; according to the calculation, the distance d is adjusted to 1.43mm, and the light field simulation effect is as follows Fig. 8A , Figure 8B shown.

[0084] According to a preferred embodiment of the present invention, the DOE partition of the diffractive optical element includes a microstructure surface, and the microstructure surface includes at least one microstructure pattern unit, and the microstructure pattern unit is designed according to the light source parameters of the light source partition corresponding to the DOE partition and the corresponding projected target light field.

[0085] According to a preferred embodiment of the present invention, the multiple target light fields are strip-shaped light fields, which are spliced ​​to form a uniform illumination light field.

[0086] According to a preferred embodiment of the present invention, since the diffractive optical element will produce pincushion-shaped distortion when performing large-field-of-view projection, the pincushion-shaped distortion can be pre-corrected for the microstructure pattern unit corresponding to the light source array according to the field-of-view area where the light field projected by each light source array is located on the overall target light field.

[0087] The present invention also provides a uniform light illumination system, which uses the method described above to eliminate crosstalk. The uniform light illumination system and the target light field formed by splicing the strip light field are described in detail above and will not be described again here.

[0088] The present invention also provides an electronic device, comprising the uniform light illumination system as described above.

[0089] The preferred embodiment of the present invention provides a method for eliminating crosstalk in a partitioned uniform light illumination system, by adjusting the distance between the VCSEL partitioned light source and the diffractive optical element, so that specific points in part of the target light field coincide with corresponding points in the crosstalk light field, and the adjustment interval of the distance between the VCSEL partitioned light source and the diffractive optical element is obtained by multi-point calculation and multi-partition calculation, and then the optimal light field effect within the adjustment interval is obtained by simulation software. The preferred embodiment of the present invention reduces the crosstalk of the target light field by precisely controlling and adjusting the diffractive optical element when assembling it, and can project a clear uniform light field with a large field of view. The method provided by the present invention is applied to the partitioned uniform light illumination system, which provides technical support for the uniform light illumination required by the DTOF system.

[0090] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for eliminating interference of a crosstalk light field on a target light field by a partitioned uniform illumination system, wherein the partitioned uniform illumination system comprises a light source having a plurality of light source partitions and a diffractive optical element having a plurality of DOE partitions corresponding to the plurality of light source partitions, the light source partition irradiates the corresponding DOE partition and projects the target light field on the target surface, the light source partition eccentrically irradiates the DOE partition adjacent to the corresponding DOE partition and projects the crosstalk light field on the target surface, the DOE partition adjacent to the corresponding DOE partition corresponds to another light source partition, the another light source partition irradiates the DOE partition adjacent to the corresponding DOE partition and projects another target light field on the target surface, the method comprises: S101: Determine a specific point of the target light field, a specific point of another target light field, and a point of the crosstalk light field corresponding to the specific point; and S102: determining a distance between the diffractive optical element and the light source so that a specific point of the target light field coincides with a corresponding point of the crosstalk light field on a target surface, comprising: Determine the distance between a specific point of the other target light field and a corresponding point of the crosstalk light field according to the center distance between the light source subarea and the other light source subarea, the distance between the diffractive optical element and the light source, and the field angle of the crosstalk light field; Determining the distance between the specific point of the target light field and the corresponding point of the crosstalk light field according to the distance between the specific point of the other target light field and the corresponding point of the crosstalk light field; By adjusting the distance between the diffractive optical element and the light source, a specific point of the target light field is made to coincide with a corresponding point of the crosstalk light field on the target surface.

2. The method of claim 1, wherein the specific point of the target light field comprises: One or more of a point at the upper edge of the target light field in the vertical direction, a point at the upper and lower edges of the target light field in the vertical direction, and a center point in the vertical direction of the target light field.

3. The method according to claim 1 or 2, further comprising: Repeating steps S101 and S102 to determine a plurality of specific points of the target light field and a plurality of corresponding distances; A preset distance interval is determined according to the multiple distances, and the distance from the diffractive optical element to the light source is adjusted within the preset distance interval so that the crosstalk light field substantially coincides with the target light field.

4. The method according to claim 1 or 2, further comprising: For a plurality of crosstalk light fields projected on the target surface by eccentrically irradiating a plurality of DOE partitions adjacent to the corresponding DOE partition by the light source partition, repeating steps S101 and S102 to determine a specific point of the target light field and a plurality of corresponding distances; A preset distance interval is determined according to the multiple distances, and the distance from the diffractive optical element to the light source is adjusted within the preset distance interval so that the crosstalk light field substantially coincides with the target light field.

5. The method according to claim 1 or 2, wherein the DOE partition of the diffractive optical element includes a microstructure surface, the microstructure surface includes at least one microstructure pattern unit, and the microstructure pattern unit is designed according to the light source parameters of the light source partition corresponding to the DOE partition and the corresponding projected target light field.

6. The method according to claim 1 or 2, wherein the multiple target light fields are strip-shaped light fields, which are spliced ​​to form a uniform illumination light field.

7. A uniform light illumination system, using the method according to any one of claims 1 to 6 to eliminate the interference of a crosstalk light field on a target light field.

8. An electronic device comprising the uniform light illumination system according to claim 7.

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