A beam quality analyzer and laser transmitter galvanometer calibration method

Abstract

The present invention discloses a beam quality analyzer and a laser emitter galvanometer calibration method. The analyzer includes a shell and a splitter structure that can split a light beam into a main light beam and a light beam to be analyzed. The shell is provided with an objective lens, a splitter structure and a camera in sequence along the light path direction; the shell is also provided with a main light beam exit hole located on one side of the splitter structure. The analysis and calibration method includes extracting a beam component from the light beam emitted by the laser emitter to form a light beam to be analyzed, irradiating the origin of the reference plane and forming a light spot; allowing the galvanometer in the laser emitter to scan a certain angle to obtain the actual movement distance of the light spot, and calculating the difference between the actual movement distance of the light spot and the ideal movement distance of the light spot. The beam quality analyzer and the laser emitter galvanometer calibration method provided by the present invention can quickly obtain the light spot image of the light beam, which is conducive to improving the accuracy of the beam quality analysis, thereby improving the calibration efficiency of the laser emitter.

Description

Technical Field

[0001] The present invention relates to the field of beam quality analysis, and in particular to a beam quality analyzer and a laser emitter galvanometer calibration method. Background Art

[0002] After the production of the laser transmitter is completed, the beam quality needs to be analyzed and calibrated. The main analysis contents include the roundness of the beam and whether the midpoint of the light spot is the point with the highest brightness. At present, due to the lack of analysis equipment, the commonly used method is to use the laser transmitter beam to perform multiple laser dot markings on a fixed plate, and use various measurement platforms to detect the position of the dot to determine whether the laser scanning galvanometer has positioning errors. However, due to the thermal effect of the laser beam, when marking the plate, the size of the dot formed is slightly larger than the spot size, and the uneven heat distribution may cause the contour shape of the actual dot to be different from the shape of the light spot wheel frame, resulting in the inability to accurately analyze the actual roundness of the beam and the position of the midpoint of the light spot. This method is not only cumbersome to operate and takes a long time to measure, but also there is a large error between the position of the focused light spot and the actual one, and it is also impossible to obtain beam quality information. Summary of the Invention

[0003] The purpose of the present invention is to provide a beam quality analyzer and a laser emitter galvanometer calibration method, which can quickly obtain a light spot image of the light beam, thereby improving the accuracy of beam quality analysis and thus improving the calibration efficiency of the laser emitter.

[0004] To achieve the above-mentioned purpose, the present invention provides a beam quality analyzer, comprising a shell and a splitting structure capable of splitting a light beam into a main beam and a light beam to be analyzed, wherein the shell is provided with an objective lens, the splitting structure and a camera in sequence along the direction of the light path; the shell is also provided with a main beam light outlet located on one side of the splitting structure.

[0005] As a further improvement of the present invention, the spectroscopic structure includes a first prism; the light incident reflection surface of the first prism faces the objective lens, and the light emitting surface of the first prism faces the light exit hole; the camera is arranged on the path of the light beam to be analyzed.

[0006] As a further improvement of the present invention, the light splitting structure also includes a second prism; the second prism is located on one side of the light path between the objective lens and the first prism, and the light incident reflection surface of the first prism and the lens of the camera are both facing the reflective surface of the second prism.

[0007] As a further improvement of the present invention, the housing is further provided with a light attenuation structure located between the light splitting structure and the camera.

[0008] As a further improvement of the present invention, the light attenuation structure includes at least one attenuation plate.

[0009] As a further improvement of the present invention, a slot is provided on the shell; the attenuation sheet is arranged on a mounting frame, and the mounting frame is plugged into and matched with the slot on the shell.

[0010] As a further improvement of the present invention, a light blocking plate is connected to the housing via a connector, and the light blocking plate is located on one side of the light incident end of the objective lens; a light hole is provided on the light blocking plate that is directly opposite to the light incident end of the objective lens.

[0011] To achieve the above object, the present invention further provides a laser transmitter galvanometer calibration method, comprising the following steps:

[0012] Step a: extracting a beam component from the beam emitted by the laser transmitter to form a beam to be analyzed, and allowing the beam to be analyzed to illuminate the origin of the reference surface to form a light spot;

[0013] Step b: Allow the galvanometer in the laser transmitter to scan a certain angle, and the light spot on the reference surface is offset by a certain distance relative to the origin to obtain the actual moving distance of the light spot;

[0014] Step c: Calculate the difference between the actual moving distance of the light spot and the ideal moving distance of the light spot.

[0015] As a further improvement of the present invention, after the light spot on the reference plane in step b is offset by a certain distance relative to the origin, step b also includes moving the laser emitter relative to the reference plane until the light spot is re-irradiated on the origin of the reference plane to obtain the actual movement distance of the light spot; step b is repeated multiple times to correct the value of the actual movement distance of the light spot.

[0016] As a further improvement of the present invention, the difference between the actual moving distance of the light spot and the ideal moving distance of the light spot is input into the software of the laser transmitter, and the laser transmitter realizes the calibration of the galvanometer through the software.

[0017] Beneficial effects

[0018] Compared with the prior art, the advantages of the beam quality analyzer and the laser transmitter galvanometer calibration method of the present invention are:

[0019] 1. When the quality of the beam emitted by a laser transmitter needs to be analyzed, the beam is directed through the objective lens into a beam quality analyzer. The beam is then split into a high-brightness main beam and a low-brightness beam to be analyzed using a spectroscopic structure. The camera then captures the light spot formed by the low-brightness beam to be analyzed. Due to the low brightness of the light spot of the beam to be analyzed, the human eye or software can easily distinguish the position of the highest brightness and the shape of the light spot by the brightness difference, which helps to improve the accuracy of beam quality analysis and thus improve the calibration efficiency of the laser transmitter. The low-brightness beam to be analyzed separated by the spectroscopic structure is not only convenient for observation but also does not damage the camera; the separated high-brightness main beam is emitted from the light exit hole, preventing damage to the beam quality analyzer due to high temperature.

[0020] 2. The beam quality analyzer integrates an objective lens, capable of analyzing very small focused light spots (as small as one micron). Built-in beam splitting and attenuation allow for direct injection of high-power focused lasers, eliminating the need for the user to design an external optical path for detection. The laser transmitter can be placed directly in the device without disassembling it for testing, enabling simultaneous testing during processing, meeting the demands of high-end precision processing for chips, OLED panels, and other products, while improving yield rates.

[0021] 3. Due to the varying powers of different laser emitters, the brightness of the beams to be analyzed, separated by the beam splitting structure, can also vary. To prevent the brightness of the beam from being too high, making the image obtained by the camera difficult to analyze or even damaging the camera, a light attenuation structure can further reduce the brightness of the beam to be analyzed. This makes the light spot image obtained by the camera clearer, facilitates beam quality analysis, and protects the camera.

[0022] 4. The attenuation sheet is plugged into the slot on the housing through the mounting bracket to achieve detachable installation of the attenuation sheet, allowing technicians to replace the appropriate attenuation sheet according to the laser transmitter to be analyzed, so that the camera's light spot imaging is as clear as possible.

[0023] 5. The light baffle can ensure that the laser beam can only enter the beam quality analyzer from the center line of the objective lens. Even if the laser is offset, it will not directly illuminate the housing of the beam quality analyzer and cause damage to the beam quality analyzer, thereby protecting the beam quality analyzer.

[0024] The present invention will become more apparent from the following description taken in conjunction with the accompanying drawings, which are used to illustrate embodiments of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 This is one of the partial cross-sectional views of the beam quality profiler;

[0027] Figure 2 This is the second partial cross-sectional view of the beam quality analyzer;

[0028] Figure 3 Schematic diagram of the laser transmitter galvanometer calibration method. DETAILED DESCRIPTION

[0029] Embodiments of the present invention will now be described with reference to the accompanying drawings.

[0030] Example

[0031] The specific embodiments of the present invention are as follows Figures 1 to 2 As shown, a beam quality analyzer includes a housing 1 and a beam splitting structure 3 capable of splitting a light beam into a main beam and a beam to be analyzed. An objective lens 2, the beam splitting structure 3, and a camera 7 are sequentially arranged on the housing 1 along the optical path. The housing 1 is also provided with a main beam exit hole 11 located on one side of the beam splitting structure 3. The camera 7 is provided with a data cable connector 71 for connecting to a display device.

[0032] The spectroscopic structure 3 includes a first prism 31. The light incident reflection surface of the first prism 31 faces the objective lens 2, and the light exit surface of the first prism 31 faces the light exit hole 11. The camera 7 is arranged on the path of the light beam to be analyzed. In this embodiment, the spectroscopic structure 3 also includes a second prism 32, and the cross-sections of the first prism 31 and the second prism 32 are both triangular. The second prism 32 is located on one side of the light path between the objective lens 2 and the first prism 31, and the light incident reflection surface of the first prism 31 and the lens of the camera 7 are both facing the reflective surface of the second prism 32. The lens of the camera 7 is symmetrical with respect to the normal of the reflective surface of the second prism 32 and the light beam to be analyzed reflected from the light incident reflection surface of the first prism 31.

[0033] The housing 1 is also provided with a light attenuation structure 6 located between the light-splitting structure 3 and the camera 7. This structure includes at least one attenuating plate. In this embodiment, the structure comprises a first attenuating plate 61 and a second attenuating plate 62. The first and second attenuating plates 61 and 62 are arranged sequentially along the light beam to be analyzed. The light attenuating structure 6 is separated from the light-splitting structure 3 by a partition having a through hole formed therein for the light beam to be analyzed to pass through.

[0034] The housing 1 is provided with a slot. The attenuation sheet is arranged on a mounting bracket 8, which is plugged into and matched with the slot on the housing 1. The outer side of the mounting bracket 8 is fixedly connected to the housing 1 by screws.

[0035] A light barrier 4 is connected to the housing 1 via a connector 5. This light barrier 4 is located on one side of the light-entering end of the objective lens 2. Light barrier 4 is provided with a light aperture 41 that directly faces the light-entering end of the objective lens 2. Light barrier 4 is relatively thick to prevent direct penetration by laser light within a short period of time. In this embodiment, the connector 5 is a connecting post, four in number. Each connecting post connects between the light barrier 4 and the four corners of the housing 1.

[0036] like Figure 3 As shown, the galvanometer of the laser transmitter 10 is calibrated using the above-mentioned beam quality analyzer, which includes the following steps:

[0037] Step a: Place a beam quality analyzer on a two-dimensional or three-dimensional mobile platform 9; extract beam components from the beam emitted by the laser emitter 10 to form a beam to be analyzed, and allow the beam to be analyzed to illuminate the origin of the reference surface to form a light spot. Specifically, the lens of the beam quality analyzer's camera 7 serves as the reference surface. The laser light emitted from the laser emitter 10 passes through the objective lens 2, the beam splitting structure 3, the light attenuation structure 6, and illuminates the lens of the camera 7. The light spot of the beam to be analyzed is obtained by the camera 7.

[0038] Step b: Let the galvanometer 12 in the laser emitter 10 scan a certain angle, and the light spot on the reference plane of the camera 7 is offset by a certain distance relative to the origin; use the mobile platform 9 to move the laser emitter 10 relative to the reference plane of the camera 7 until the light spot is re-irradiated on the origin of the reference plane of the camera 7, and obtain its moving distance information from the working data of the mobile platform 9.

[0039] Repeat step b several times to correct the actual moving distance of the light spot.

[0040] Step c: Calculate the difference between the actual moving distance of the light spot and the ideal moving distance of the light spot.

[0041] Step d: The difference between the actual moving distance of the light spot and the ideal moving distance of the light spot is input into the software of the laser transmitter 10, and the laser transmitter 10 calibrates the galvanometer 12 through the software.

[0042] Because the brightness of the analyzed beam spot is low, the human eye or software can easily distinguish the peak brightness position and edge shape of the spot by the brightness difference, which helps improve the accuracy of beam quality analysis and thus the efficiency of laser transmitter calibration. The low-brightness analyzed beam separated by the beam splitting structure 3 is not only convenient for observation but also does not damage the camera 7. The separated high-brightness main beam is emitted from the light exit hole, preventing damage to the beam quality analyzer due to high temperature.

[0043] The present invention has been described above in conjunction with the best embodiments, but the present invention is not limited to the embodiments disclosed above, but should cover various modifications and equivalent combinations based on the essence of the present invention.

Claims

1. A beam quality analyzer, characterized in that: The invention comprises a housing (1) and a light splitting structure (3) capable of splitting a light beam into a main light beam and a light beam to be analyzed, wherein the housing (1) is provided with an objective lens (2), the light splitting structure (3) and a camera (7) in sequence along the light path direction; the housing (1) is also provided with a main light beam light exit hole (11) located on one side of the light splitting structure (3); the light splitting structure (3) comprises a first prism (31); the light incident reflection surface of the first prism (31) faces the objective lens (2), and the light exit surface of the first prism (31) faces the light exit hole (11); the camera (7) is arranged on the path of the light beam to be analyzed; the light splitting structure (3) The invention also includes a second prism (32); the second prism (32) is located on one side of the optical path between the objective lens (2) and the first prism (31); the light incident reflection surface of the first prism (31) and the lens of the camera (7) are both oriented toward the light reflecting surface of the second prism (32); a light blocking plate (4) is connected to the housing (1) via a connecting member (5); the light blocking plate (4) is located on one side of the light incident end of the objective lens (2); a light hole (41) is provided on the light blocking plate (4) and is directly opposite to the light incident end of the objective lens (2); and a light attenuation structure (6) is also provided on the housing (1) and is located between the light splitting structure (3) and the camera (7).

2. A beam quality profiler according to claim 1, characterized in that: The light attenuation structure (6) comprises at least one attenuation plate.

3. A beam quality analyzer according to claim 2, characterized in that: The housing (1) is provided with a slot; the attenuation sheet is arranged on a mounting frame (8), and the mounting frame (8) is plugged into and matched with the slot on the housing (1).

4. A method for calibrating a galvanometer of a laser transmitter using the beam quality analyzer according to any one of claims 1 to 3, characterized in that The following steps are involved: Step a: extracting a beam component from the light beam emitted by the laser emitter (10) to form a light beam to be analyzed, and allowing the light beam to be analyzed to irradiate the origin of the reference plane and form a light spot; specifically, using the lens of the camera (7) of the beam quality analyzer as the reference plane, the laser light emitted from the laser emitter (10) passes through the objective lens (2), the light splitting structure (3), the light attenuation structure (6) in sequence and irradiates the lens of the camera (7), and the light spot of the light beam to be analyzed is obtained through the camera (7); Step b: allowing the galvanometer (12) in the laser transmitter (10) to scan a certain angle, so that the light spot on the reference surface is offset by a certain distance relative to the origin, and the actual moving distance of the light spot is obtained; Step c: Calculate the difference between the actual moving distance of the light spot and the ideal moving distance of the light spot; After the light spot on the reference plane in step b is offset by a distance relative to the origin, step b further comprises moving the laser emitter (10) relative to the reference plane until the light spot is re-irradiated on the reference plane origin, and obtaining the actual movement distance of the light spot; step b is repeated multiple times to correct the value of the actual movement distance of the light spot; Step d: inputting the difference between the actual moving distance of the light spot and the ideal moving distance of the light spot into the software of the laser transmitter (10), and the laser transmitter (10) realizes the calibration of the galvanometer (12) through the software.

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