Device and method for controlling beam divergence angle of semiconductor laser

Abstract

The invention relates to a semiconductor laser beam divergence angle control device and method, and belongs to the technical field of semiconductor lasers. The device comprises a controller, a diaphragm, a guide rail, a lens adjusting frame and a filtering assembly, the diaphragm and the lens adjusting frame are arranged on the upper side of the guide rail through sliding blocks, the filtering assembly is arranged on the top of the lens adjusting frame, and the diaphragm and the lens adjusting frame are both connected with the controller. The lower limit of the light beam divergence angle can be controlled during coupling of the semiconductor laser, the annular light beam is generated, and the energy distribution of the light beam is more uniform.

Description

Technical Field

[0001] The present invention relates to a device and method for controlling the beam divergence angle of a semiconductor laser, belonging to the technical field of semiconductor lasers. Background Art

[0002] Compared with solid-state lasers and gas lasers, semiconductor lasers have the advantages of high efficiency, small size, light weight, long life, high reliability, easy modulation and low price. They are the fastest-growing among all lasers. With the progress of growth technology, the improvement of packaging capabilities and the cost reduction, the application fields of semiconductor lasers are constantly expanding, such as in the fields of medical aesthetics, industrial welding, cutting, communication, military and display.

[0003] Currently, semiconductor lasers usually increase the chip quantity to improve power. A mainstream method is bar array packaging, that is, multiple semiconductor laser chips are connected in parallel in the slow axis direction. Due to the inherent defects of the semiconductor laser structure itself, the emission sizes of the fast and slow axes of the active region in the directions parallel and perpendicular to the P-N junction are severely asymmetric, resulting in poor output beam quality, a large beam divergence angle, and obvious differences in the horizontal and vertical directions. Therefore, it is common to compress the divergence angles of the fast and slow axes and couple the beam into the optical fiber through a focusing lens. To ensure a high coupling efficiency, the diameter of the compressed beam is smaller than the diameter of the optical fiber, that is, the compressed beam may be focused at different positions on the end face of the optical fiber. Due to the way the laser propagates in the optical fiber, the positions and angles at which the beam enters the optical fiber are different, resulting in different beam divergence angles of the optical fiber output.

[0004] The beam divergence angle is an important parameter of semiconductor lasers. According to different application requirements, the required beam divergence angle sizes are also different. Therefore, how to achieve precise control of the beam divergence angle is particularly important for semiconductor laser packaging.

[0005] Currently, an aperture is usually used to control the beam divergence angle of the laser. This device can only control the upper limit of the beam divergence angle during the coupling of the semiconductor laser, cannot control the lower limit of the beam divergence angle, and cannot realize the production of a ring-shaped beam, making it difficult to meet the different requirements for the beam divergence degree in the current market. Summary of the Invention

[0006] Aiming at the deficiencies of the prior art, the present invention provides a device and method for controlling the beam divergence angle of a semiconductor laser, which can control the lower limit of the beam divergence angle during the coupling of the semiconductor laser, generate a ring-shaped beam, and make the energy distribution of the beam more uniform.

[0007] The technical solution of the present invention is as follows:

[0008] A semiconductor laser beam divergence angle control device, comprising a controller, a diaphragm, a guide rail, a lens adjustment bracket and a filter assembly, wherein:

[0009] The diaphragm and the lens adjustment bracket are respectively arranged on the upper side of the guide rail through sliders. A filter assembly is arranged on the top of the lens adjustment bracket. Both the diaphragm and the lens adjustment bracket are connected to the controller.

[0010] Preferably according to the present invention, the lens adjustment bracket includes a two-dimensional adjustment platform, a motor and a support rod. The bottom of the two-dimensional adjustment platform is slidably connected to the guide rail through a slider. The top of the two-dimensional adjustment platform is hinged with a support rod. One side of the support rod is connected to the output shaft of the motor through gear meshing. The angle of the support rod is adjusted by the motor. The motor is fixed on the two-dimensional adjustment platform. A filter assembly is arranged on the top of the support rod.

[0011] Preferably according to the present invention, the filter assembly includes a filter A and a filter B. The filter B is fixedly arranged at the central position on one side of the filter A. The filter A is fixed on the support rod.

[0012] Preferably according to the present invention, both the filter A and the filter B are circular sheets, and the radius of the filter A is larger than that of the filter B.

[0013] Preferably according to the present invention, an included angle of 5-10° is arranged between the filter A and the filter B to prevent the laser from reflecting along the original optical path and damaging the chip.

[0014] Preferably according to the present invention, the transmittance of the filter A is 99%, and the reflectivity of the filter B is 99%.

[0015] The control method of the above semiconductor laser beam divergence angle control device is as follows:

[0016] (1) When a non-hollow beam needs to be coupled out, adjust the height of the lens adjustment bracket so that the filter assembly does not block the beam output by the laser. The controller controls the size of the diaphragm so that the coupled beam is non-hollow and the divergence angle meets the requirements;

[0017] (2) When a ring-shaped beam needs to be coupled out, adjust the height of the lens adjustment bracket so that the center of the filter A and the center of the diaphragm are at the same horizontal height. The controller adjusts the size of the diaphragm and adjusts the distance between the diaphragm and the filter A so that the coupled beam is ring-shaped.

[0018] The beneficial effects of the present invention are as follows:

[0019] 1. By adjusting the size of the light passing aperture of the diaphragm and the distance between the diaphragm and the filter A, the present invention enables the power of the coupled beam blocked by the diaphragm and the filter to be minimized when the coupled beam meets the theoretical optimal divergence angle, achieving precise control of the beam divergence angle.

[0020] 2. The present invention can achieve mass production of annular light beams, meet the requirements of some special industries for annular light beams, and can achieve independent control of the beam divergence angle of each optical path of a multi-chip laser, making the overall output beam of the multi-chip laser more uniform and more in line with Gaussian distribution. Description of the Drawings

[0021] Figure 1 is a side view of the present invention;

[0022] Figure 2 is a schematic three-dimensional structure diagram of the present invention;

[0023] Figure 3 is a schematic structure diagram of the filter assembly of the present invention;

[0024] Among them: 1. Controller; 2. Diaphragm; 3. Guide rail; 4. Lens adjustment bracket; 5. Filter A; 6. Filter B. Detailed Embodiments

[0025] The present invention will be further described below by way of examples in conjunction with the drawings, but not limited thereto.

[0026] Example 1:

[0027] As Figures 1-3 shown, this embodiment provides a semiconductor laser beam divergence angle control device, including a controller 1, a diaphragm 2, a guide rail 3, a lens adjustment bracket 4 and a filter assembly, where:

[0028] The diaphragm 2 and the lens adjustment bracket 4 are respectively arranged on the upper side of the guide rail 3 through sliders. The filter assembly is arranged on the top of the lens adjustment bracket 4. Both the diaphragm 2 and the lens adjustment bracket 4 are connected to the controller 1. The diaphragm is an existing device with an adjustable aperture.

[0029] The lens adjustment bracket 4 includes a two-dimensional adjustment platform, a motor and a support rod. The bottom of the two-dimensional adjustment platform is slidably connected to the guide rail through a slider. The top of the two-dimensional adjustment platform is hinged with a support rod. One side of the support rod is connected to the output shaft of the motor through gear meshing. The angle of the support rod is adjusted by the motor (the motor and the hinge are common mechanical flipping components and are not shown in the figure). The motor is fixed on the two-dimensional adjustment platform, and the filter assembly is arranged on the top of the support rod.

[0030] The filter assembly includes a filter A 5 and a filter B 6. The filter B 6 is fixedly arranged at the center position on one side of the filter A 5. The filter A 5 is fixed to the support rod.

[0031] Both the filter A 5 and the filter B 6 are circular sheets, and the radius of the filter A is larger than that of the filter B.

[0032] An included angle of 5 - 10° is provided between the filter A 5 and the filter B 6 to prevent the laser from reflecting along the original optical path and damaging the chip.

[0033] The transmittance of the filter A5 is 99%, and the reflectivity of the filter B6 is 99%.

[0034] The control method of the above semiconductor laser beam divergence angle control device is as follows:

[0035] (1) When a non-hollow beam needs to be coupled out, adjust the height of the lens adjustment bracket 4 so that the filter assembly does not block the beam output by the laser. The controller 1 controls the size of the aperture 2 so that the coupled beam is non-hollow and the divergence angle meets the requirements;

[0036] (2) When a ring beam needs to be coupled out, adjust the height of the lens adjustment bracket 4 so that the center of the filter A is at the same horizontal height as the center of the aperture. The controller adjusts the size of the aperture and the distance between the aperture and the filter A so that the coupled beam is in a ring shape, and the final effect is as Figure 1 shown.

[0037] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention. Any equivalent structural transformation made under the concept of the present invention by using the content of the specification and drawings of the present invention, or directly / indirectly applied in other related technical fields, is included in the patent protection scope of the present invention.

Claims

1. A semiconductor laser beam divergence angle control device, characterized in that It includes a controller, a diaphragm, a guide rail, a lens adjustment bracket, and a filter assembly, where: The diaphragm and the lens adjustment bracket are respectively arranged on the upper side of the guide rail through sliders. A filter assembly is arranged on the top of the lens adjustment bracket. Both the diaphragm and the lens adjustment bracket are connected to the controller.

2. The semiconductor laser beam divergence angle control device according to claim 1, wherein The lens adjustment bracket includes a two-dimensional adjustment platform, a motor, and a support rod. The bottom of the two-dimensional adjustment platform is slidably connected to the guide rail through a slider. The top of the two-dimensional adjustment platform is hinged with a support rod. One side of the support rod is connected to the output shaft of the motor through gear meshing. The motor is fixed on the two-dimensional adjustment platform. A filter assembly is arranged on the top of the support rod.

3. The semiconductor laser beam divergence angle control device according to claim 2, characterized in that, The filter assembly includes filter A and filter B. Filter B is fixedly arranged at the central position on one side of filter A. Filter A is fixed on the support rod.

4. The semiconductor laser beam divergence angle control device according to claim 3, characterized in that, Both filter A and filter B are circular sheets, and the radius of filter A is larger than that of filter B.

5. The semiconductor laser beam divergence angle control device according to claim 4, characterized in that, An angle of 5-10° is provided between filter A and filter B.

6. The semiconductor laser beam divergence angle control device according to claim 5, wherein The transmittance of filter A is 99%, and the reflectivity of filter B is 99%.

7. The control method of the semiconductor laser beam divergence angle control device according to claim 6, characterized in that, The steps are as follows: (1) When a non-hollow beam needs to be coupled out, adjust the height of the lens adjustment bracket so that the filter assembly does not block the beam output by the laser. The controller controls the size of the diaphragm so that the coupled beam is non-hollow and the divergence angle meets the requirements. (2) When a ring beam needs to be coupled out, adjust the height of the lens adjustment bracket so that the center of filter A and the center of the diaphragm are at the same horizontal height. The controller adjusts the size of the diaphragm and the distance between the diaphragm and filter A to make the coupled beam annular.

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