Parallel beam collimation method and device

Abstract

The invention discloses a parallel light beam collimation method and a parallel light beam collimation device, which are used for collimation of parallel light beams which are not parallel to each other and of which extension lines intersect on the same plane, and comprises the following steps: determining the position and parameters of a convex lens; mutually non-parallel parallel light beams are incident to the convex lens so as to change the propagation direction of the light beams, and the light beams are converged on a rear focal plane of the convex lens; determining the position and parameters of the convex lens array; the light beams converged on the rear focal plane of the convex lens are emitted to the convex lens array after diverging and extending in the new direction, so that divergence angle compensation and correction are carried out on all the light beams, and the light beams are collimated into parallel light. According to the invention, efficient, accurate and stable collimation of parallel light beams which are not parallel to each other can be realized, the method is simple to operate, and the device is simple in structure and low in cost.

Description

Technical Field

[0001] The invention belongs to the field of optical technology, and in particular relates to a parallel light beam collimation method and device. Background Art

[0002] In the field of optical technology, effective processing of light beams has always been the core factor driving the development of many optical applications, widely involving many important fields such as laser communications, optical imaging, and laser processing.

[0003] Traditional beam collimation technology focuses on a single or specific angle beam. In the early days, a simple optical lens structure was used to process a single parallel beam, and collimation was achieved by adjusting the focal length and position. However, when faced with multiple non-parallel parallel beams, due to the complex propagation path, traditional single lenses or simple combination lenses are difficult to accurately and effectively collimate, and their applications are limited.

[0004] With the development of technology, improved collimation devices and methods have emerged. For example, a complex reflector combination architecture is used to try to change the direction of the light beam to achieve collimation, but due to the complex structure, it is difficult to build and debug. In addition, multiple reflections introduce light loss and aberrations, which reduce the accuracy and stability of collimation and affect the imaging or processing quality. There are also solutions based on special materials or grating structures, which have strict requirements on the characteristics of the light beam and a narrow range of applications. In addition, the acquisition of special materials and the preparation of gratings are complex and have high technical barriers, resulting in a significant increase in costs. This has limited large-scale promotion and application from an economic perspective and is difficult to meet the needs of beam collimation in multiple scenarios. Better collimation technology innovation is urgently needed.

[0005] Therefore, developing a new type of beam collimation technology to achieve beam collimation with a simpler structure and lower cost has important scientific significance and application value for expanding the application scope of beam collimation technology and improving its practicality. Summary of the invention

[0006] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a parallel light beam collimation method and device, which can achieve efficient, accurate and stable collimation of mutually non-parallel parallel light beams, the method is simple to operate, the device structure is simple and the cost is low.

[0007] The present invention provides the following technical solutions: In a first aspect, a parallel light beam collimation method is provided, which is used for collimating parallel light beams that are non-parallel to each other and whose extended lines intersect in the same plane, comprising: Determine the position and parameters of the convex lens; Allowing mutually non-parallel parallel light beams to be incident on the convex lens to change the propagation direction of the light beams and converge the light beams on the rear focal plane of the convex lens; Determine the position and parameters of the convex lens array; The light beams converged on the focal plane behind the convex lens are extended and diverged in a new direction and then incident on the convex lens array, so as to compensate and correct the divergence angle of each light beam and collimate the light beam into parallel light.

[0008] Furthermore, the method for determining the position of the convex lens includes: making the front focus of the convex lens coincide with the center of the intersection plane of the extension lines of the non-parallel parallel light beams.

[0009] Furthermore, the parameters of the convex lens include the focal length of the convex lens, and the focal length is the distance from the optical center of the convex lens to the center of the intersection plane of the extension lines of the mutually non-parallel parallel light beams.

[0010] Furthermore, the parameters of the convex lens also include the diameter of the convex lens, and the method for determining the diameter of the convex lens includes: Determine the maximum incident angle θ of mutually non-parallel parallel light beams; Calculate the radius r of the spot where the light beam converges on the focal plane behind the convex lens: r = f × tanθ, where f is the focal length of the convex lens; Then the diameter of the convex lens D≥2r.

[0011] Furthermore, the parameters of the convex lens array include an array structure, and a method for determining the array structure includes: Count the number of mutually non-parallel parallel beams as N; According to the actual spatial layout and beam distribution characteristics, the sub-lenses are distributed in an m×n array, where m×n≥N.

[0012] Furthermore, when the light beam is distributed in a rectangular shape in space, a combination with the closest values ​​of m and n is selected.

[0013] Furthermore, the parameters of the convex lens array also include the center spacing d of adjacent sub-lenses, and the center spacing d of adjacent sub-lenses must satisfy: d>2r×tanα, wherein r is the radius of the spot of the light beam converging on the focal plane behind the convex lens, and α is the divergence angle of the light beam converging on the focal plane behind the convex lens.

[0014] Furthermore, the parameters of the convex lens array also include the focal length of each sub-lens, and the focal length of each sub-lens is the same as the focal length of the convex lens.

[0015] Furthermore, the distance between the convex lens array and the convex lens is twice the focal length of the convex lens.

[0016] In a second aspect, a parallel light beam collimation device is provided, which uses the method described in the first aspect to collimate parallel light beams that are non-parallel to each other and whose extended lines intersect in the same plane; The device comprises: Convex lens, used to change the propagation direction of the light beam and converge the light beam to the back focal plane of the convex lens; The convex lens array is used to compensate and correct the divergence angle of the light beam so as to collimate the light beam into parallel light.

[0017] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention allows mutually non-parallel parallel light beams to be incident on a convex lens to change the propagation direction of the light beams, and converges the light beams on the rear focal plane of the convex lens, thereby ensuring the accuracy and stability of collimation; then the light beams converged on the rear focal plane of the convex lens are diverged and extended in a new direction and then incident on the convex lens array to compensate and correct the divergence angle of each light beam, so that the light beams are collimated into parallel light, thereby achieving the collimation of mutually non-parallel parallel light beams. The method is simple to operate and has low cost; (2) The present invention makes the front focal point of the convex lens coincide with the center of the intersection plane of the extension lines of the non-parallel parallel light beams, so that the light beams can be efficiently converged on the back focal plane of the convex lens, which is beneficial to improving the collimation accuracy and stability; (3) The present invention selects and confirms a suitable convex lens array based on information such as the number of mutually non-parallel parallel light beams, which is beneficial to improving the collimation efficiency of mutually non-parallel parallel light beams, providing convenient control for optical system design optimization, and facilitating integrated applications in multiple optical fields; (4) The parallel light beam collimation device provided by the present invention adopts conventional optical elements and has a simple structure, low cost, and is easy to promote and maintain. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of the principle of the parallel light beam collimation method in an embodiment of the present invention; Figure 2 yes Figure 1 Schematic diagram of the structure in the YZ direction; Figure 3 yes Figure 1 Schematic diagram of the structure in the XZ direction; Figure 4 Schematic diagram of the structure of a lens array of m×n=5×4 in an embodiment of the present invention; Marked in the figure: 101, convex lens; 102, convex lens array; 103, light beam emitting surface; 104, back focal plane; 105, extended line intersection plane. DETAILED DESCRIPTION

[0019] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0020] It should be noted that in the description of the present invention, the terms "front", "rear", "left", "right", "up", "down", "inside", "outside" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and do not require that the present invention must be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0021] Example 1

[0022] like Figure 1~Figure 3 As shown, this embodiment provides a parallel light beam collimation method for collimating parallel light beams that are non-parallel to each other and whose extended lines intersect in the same plane, comprising the following steps: Step 1: Determine the position and parameters of the convex lens 101.

[0023] (1) The method for determining the position of the convex lens 101 includes: making the front focus of the convex lens 101 coincide with the center of the intersection plane 105 of the extension lines of the non-parallel parallel light beams.

[0024] (2) The parameters of the convex lens 101 include: the focal length of the convex lens 101 and the diameter of the convex lens 101 .

[0025] The focal length of the convex lens 101 is the distance from the optical center of the convex lens 101 to the center of the plane 105 where the extension lines of the non-parallel parallel light beams intersect.

[0026] The diameter of the convex lens has an impact on the collimation result: if the diameter is too small, part of the light beam will not be able to enter the convex lens, causing light energy loss and affecting the collimation effect; if the diameter is too large, it may increase the cost and volume of the device and may introduce more aberrations. In this embodiment, the method for determining the diameter of the convex lens 101 includes the following steps: Determine the maximum incident angle θ of the mutually non-parallel parallel light beams emitted from the light beam emitting surface 103; Calculate the radius r of the spot where the light beam converges on the focal plane 104 behind the convex lens: r=f×tanθ, where f is the focal length of the convex lens; Then the diameter of the convex lens D≥2r.

[0027] Step 2: The mutually non-parallel parallel light beams emitted from the light beam emitting surface 103 are incident on the convex lens 101 , and the focusing characteristics of the convex lens 101 are used to change the propagation direction of the light beams and converge the light beams on the rear focal plane 104 of the convex lens 101 .

[0028] Step 3: Determine the position and parameters of the convex lens array 102.

[0029] The convex lens array 102 is composed of a plurality of convex lenses (sub-lenses) arranged in an m×n arrangement, wherein m is the number of sub-lenses in the y direction, and n is the number of sub-lenses in the x direction, which determines the number of non-parallel parallel light beams in the entire space that can be collimated.

[0030] The parameters of the convex lens array 102 include the array structure, the center distance d between adjacent sub-lenses, and the focal length of each sub-lens.

[0031] The method for determining the array structure specifically refers to determining the values ​​of m and n, and includes the following steps: counting the number of mutually non-parallel parallel light beams as N; distributing the sub-lenses in an m×n array according to the actual spatial layout and light beam distribution characteristics, wherein m×n≥N.

[0032] In practical applications, when the light beam is distributed in a rectangular shape in space, the combination with the closest value of m and n is selected. For example, Figure 1~Figure 3 If there are 6 non-parallel parallel beams, you can choose an array structure of m=3 and n=2. For example, if there are 20 non-parallel parallel beams, you can choose Figure 4 The array structure shown is m=5, n=4.

[0033] The center distance d of adjacent sub-lenses must ensure that there is no light beam interference between adjacent sub-lenses, and at the same time ensure that the light beam can enter each sub-lens evenly and effectively. Specifically, the center distance d of adjacent sub-lenses must satisfy: d>2r×tanα, where r is the radius of the light spot where the light beam converges on the focal plane behind the convex lens, and α is the divergence angle of the light beam that converges on the focal plane behind the convex lens.

[0034] The focal length of each sub-lens is the same as the focal length of the convex lens 101, which is f. The diameter D of the sub-lens 0 ≥2f×tanβ, where β is the divergence angle of the light beam after passing through the focal plane of the convex lens. The distance between the convex lens array 102 and the convex lens 101 is twice the focal length of the convex lens 101, that is, 2f.

[0035] Step 4, the light beam converged on the rear focal plane 104 of the convex lens is extended in a new direction and then incident on the convex lens array 102, so that each sub-lens can perform divergence angle compensation operation on one light beam respectively. Each sub-lens accurately adjusts the light beam passing through it according to its own optical parameters, so that the divergence angle of each light beam originally diverged due to the previous operation can be effectively corrected, and each light beam is collimated into parallel light, finally achieving the effect of successfully converting mutually non-parallel parallel light beams into mutually parallel parallel light beams.

[0036] All convex lenses used in the present invention are convex lenses made of conventional materials in the optical field and will not be described separately.

[0037] Example 2

[0038] This embodiment adopts the method described in Embodiment 1 to perform light beam collimation in a laser cutting scenario.

[0039] In the laser cutting equipment, there are 7 parallel light beams that are non-parallel to each other and whose extension lines intersect on a certain plane. According to the position of the intersection plane, the focal length of the convex lens is determined to be 40mm, so that the front focus of the selected convex lens coincides with the center of the intersection plane of the extension lines of the non-parallel parallel light beams. Considering that the incident angle of the light beam is in the range of -25°~25°, in order to ensure that all the light beams enter the convex lens and the focusing effect is good, a convex lens with a diameter of 7 cm is selected. These light beams are incident on the convex lens of this specific focal length, and the focusing characteristics of the convex lens are used to change the original propagation direction of the light beam, and converge on the back focal plane of the convex lens along a specific path.

[0040] Starting from the convergence point of the focal plane behind the convex lens, the light beam diverges and extends in a new direction and enters the convex lens array. According to the number of light beams, the convex lens array is set to a 2×4 array structure, and the center spacing between adjacent sub-lenses is calculated to be 1.2 mm. This structural design ensures that the light beam enters each sub-lens evenly and effectively. In practice, the divergent light beam enters the convex lens array at a divergence angle of 8°~12° and can be smoothly received and processed by each sub-lens.

[0041] Due to the special structure of the convex lens array and the parameter design of each sub-lens, each sub-lens can perform divergence angle compensation operation for each beam of light. Each sub-lens can accurately adjust the light beam passing through it according to its own optical parameters. For example, by optimizing the parameters such as the curvature of the sub-lens, the light beam that originally has a certain divergence can be collimated into parallel light with extremely high parallelism. After testing, the deviation of the parallel light is within the range of ±0.15°. During the laser cutting process, the energy of the collimated beam is more concentrated, which effectively reduces the burrs on the cutting edge and the width of the heat-affected zone, and improves the cutting quality.

[0042] Example 3

[0043] This embodiment adopts the method described in Embodiment 1 to perform light beam collimation in the projector optical system.

[0044] In the projector optical system, there are 9 parallel light beams that are non-parallel to each other and whose extension lines intersect at a certain plane. According to the position of the intersection plane, the focal length of the convex lens is determined to be 35mm, so that the front focus of the selected convex lens coincides with the center of the intersection plane of the extension lines of the non-parallel parallel light beams. Considering that the incident angle of the light beam is in the range of -20°~20°, a convex lens with a diameter of 6 cm is selected. These light beams are incident on the convex lens with a specific focal length, and the focusing characteristics of the convex lens are used to change the original propagation direction of the light beam and converge on the focal plane of the convex lens along a specific path.

[0045] Starting from the convergence point of the focal plane behind the convex lens, the light beam diverges and extends in a new direction and enters the convex lens array. According to the light beam situation, the convex lens array is determined to be a 3×3 array structure, and the center spacing between adjacent sub-lenses is 1 mm. At this time, the divergent light beam enters the convex lens array with a divergence angle of 6°~10°, and can be smoothly received and processed by each sub-lens.

[0046] Due to the special structure of the convex lens array and the parameter design of each sub-lens, each sub-lens can perform divergence angle compensation for each beam of light. Each sub-lens accurately adjusts the light beam passing through it according to its own optical parameters. For example, by adjusting the curvature and other parameters of the sub-lens, the light beam that originally has a certain divergence is collimated into parallel light. After testing, the deviation of parallel light is within the range of ±0.2°. In the actual use of the projector, the collimated light beam significantly improves the clarity of the projected image, improves the resolution, and makes the color more uniform, effectively improving the projection effect.

[0047] Example 4

[0048] like Figure 1 As shown, this embodiment provides a parallel light beam collimation device, which uses the method described in Example 1 to collimate parallel light beams that are non-parallel to each other and whose extended lines intersect in the same plane; the device includes a convex lens 101 and a convex lens array 102 arranged in sequence along the propagation direction of the light beam; the convex lens is used to change the propagation direction of the light beam and converge the light beam on the back focal plane of the convex lens; the convex lens array is used to compensate and correct the divergence angle of the light beam, so that the light beam is collimated into parallel light.

[0049] In summary, the parallel light beam collimation method and device provided by the present invention can be used to collimate mutually non-parallel parallel light beams, and the mentioned elements are all conventional optical elements with a simple structure. The user can select the number of sub-lenses in the lens array according to the actual needs and the number of non-parallel parallel light beams, and select the size of the convex lens and the spatial position of the sub-lenses in the convex lens array according to the divergence angle range of the non-parallel parallel light beams.

[0050] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for collimating a parallel light beam, characterized in that: Used for collimation of parallel beams that are non-parallel to each other and whose extended lines intersect in the same plane, including: Determine the position and parameters of the convex lens; Allowing mutually non-parallel parallel light beams to be incident on the convex lens to change the propagation direction of the light beams and converge the light beams on the rear focal plane of the convex lens; Determine the position and parameters of the convex lens array; The light beams converged on the focal plane behind the convex lens are extended and diverged in a new direction and then incident on the convex lens array, so as to compensate and correct the divergence angle of each light beam and collimate the light beam into parallel light.

2. The parallel light beam collimation method according to claim 1, characterized in that: The method for determining the position of the convex lens includes: making the front focus of the convex lens coincide with the center of the intersection plane of the extension lines of the non-parallel parallel light beams.

3. The parallel light beam collimation method according to claim 2, characterized in that: The parameters of the convex lens include the focal length of the convex lens, and the focal length is the distance from the optical center of the convex lens to the center of the intersection plane of the extension lines of the mutually non-parallel parallel light beams.

4. The parallel light beam collimation method according to claim 1, characterized in that: The parameters of the convex lens also include the diameter of the convex lens. The method for determining the diameter of the convex lens includes: Determine the maximum incident angle θ of mutually non-parallel parallel light beams; Calculate the radius r of the spot where the light beam converges on the focal plane behind the convex lens: r = f × tanθ, where f is the focal length of the convex lens; Then the diameter of the convex lens D≥2r.

5. The parallel light beam collimation method according to claim 1, characterized in that: The parameters of the convex lens array include an array structure, and a method for determining the array structure includes: Count the number of mutually non-parallel parallel beams as N; According to the actual spatial layout and beam distribution characteristics, the sub-lenses are distributed in an m×n array, where m×n≥N.

6. The parallel light beam collimation method according to claim 5, characterized in that: When the light beam is distributed in a rectangular shape in space, select the combination with the closest values ​​of m and n.

7. The parallel light beam collimation method according to claim 1, characterized in that: The parameters of the convex lens array also include the center spacing d of adjacent sub-lenses, and the center spacing d of adjacent sub-lenses must satisfy: d>2r×tanα, where r is the radius of the spot of the light beam converged on the focal plane behind the convex lens, and α is the divergence angle of the light beam converged on the focal plane behind the convex lens.

8. The parallel light beam collimation method according to claim 1, characterized in that: The parameters of the convex lens array also include the focal length of each sub-lens, and the focal length of each sub-lens is the same as the focal length of the convex lens.

9. The parallel light beam collimation method according to claim 8, characterized in that: The distance between the convex lens array and the convex lens is twice the focal length of the convex lens.

10. A parallel light beam collimation device, characterized in that: The method according to any one of claims 1 to 9 is used to collimate parallel light beams which are non-parallel to each other and whose extended lines intersect in the same plane; The device comprises: Convex lens, used to change the propagation direction of the light beam and converge the light beam to the back focal plane of the convex lens; The convex lens array is used to compensate and correct the divergence angle of the light beam so as to collimate the light beam into parallel light.

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