A semiconductor laser capable of fast switching of light spots

Abstract

The utility model discloses a kind of semiconductor lasers of fast switching light spot, belong to laser field.Its technical scheme is, a kind of semiconductor lasers of fast switching light spot, including laser main body and multiple light spot switching heads, light spot switching head includes switching head shell, one end of switching head shell is connected with laser main body, the other end is set as light window, switching head shell is also equipped with reflector in, reflector is set around the inner wall of switching head shell;Laser main body is equipped with semiconductor laser chip, control circuit board and photoelectric detector, photoelectric detector and semiconductor laser chip are electrically connected with control circuit board, photoelectric detector can receive stray light reflected by reflector and output corresponding electric signal.Reflector collects the stray light generated by skin diffuse reflection, and the intensity of stray light is detected by photoelectric detector, and feedback is given to control circuit board, the actual laser power can be judged and adjusted, and the output energy is stable.

Description

Technical Field

[0001] This invention relates to the field of lasers, and in particular to a semiconductor laser capable of rapidly switching light spots. Background Technology

[0002] Semiconductor lasers, with their high photoelectric conversion efficiency and compact size, are the mainstream light source for medical aesthetic equipment. Different treatment areas, such as the face, armpits, and limbs, require different suitable spot sizes; therefore, industry equipment commonly incorporates detachable optical switching heads to adapt to diverse clinical scenarios.

[0003] For example, the laser module and medical device provided by patent CN220122327U currently consists of two parts: a laser main unit and a detachable treatment head. The main unit integrates a semiconductor laser chip and a fast-axis collimating lens, and uses the collimating lens to perform preliminary correction on the chip's large divergence angle beam. The treatment head is assembled with the light output end of the main unit by magnetic attraction or screw tightening, and outputs a light spot of the corresponding size by matching different specifications of lenses.

[0004] However, during long-term use, the output power of the beam switch may decrease due to contamination of the cylindrical lens or output window, aging of optical components, etc., making it difficult to guarantee the stability and consistency of the output effect. Utility Model Content

[0005] This invention addresses the problem of easy power attenuation in current laser medical devices with replaceable treatment heads by providing a semiconductor laser with a rapidly switchable beam spot.

[0006] To address the aforementioned problems, the present invention employs a semiconductor laser capable of rapidly switching beam spots, comprising a laser body and multiple beam spot switching heads. Each beam spot switching head includes a switching head housing, one end of which is connected to the laser body, and the other end serving as a light-emitting window. A reflector is also provided within the switching head housing, surrounding the inner wall of the housing to reflect stray light reflected back from the skin. The laser body comprises a semiconductor laser chip, a control circuit board, and a photodetector. Both the photodetector and the semiconductor laser chip are electrically connected to the control circuit board. The photodetector receives the stray light reflected by the reflector and outputs a corresponding electrical signal. By uniformly collecting stray light generated by diffuse reflection from the skin through the reflector, stray light is prevented from impacting the semiconductor laser chip along the optical path and causing damage. Simultaneously, the photodetector detects the intensity of the stray light and feeds it back to the control circuit board, enabling the determination of the actual laser power and adjustment compensation to ensure stable output beam spot energy.

[0007] Preferably, a cylindrical lens is provided inside the switching head housing on the side near the laser body, and the reflector is located between the cylindrical lens and the light-emitting window. The cylindrical lens in front compresses and shapes the incident laser beam, improving the concentration of light energy, while the reflector in the back does not block the shaped main emitted beam. Stray light is completely intercepted between the light-emitting window and the cylindrical lens, preventing stray light from entering the cylindrical lens and chip optical path. The optical path protection and beam shaping do not interfere with each other.

[0008] Preferably, the reflector is an internally continuous frustum shape, with the smaller end of the reflector positioned close to the light-emitting window. The larger end of the frustum faces the cylindrical lens, and the smaller end is close to the light-emitting window, completely surrounding the main beam emission channel without obstructing the outward-output therapeutic laser. Stray light reflected from the skin first enters the smaller end, is reflected outwards through the inclined inner wall of the frustum, and converges, effectively collecting a large area of ​​stray light and guiding it to the rear photodetector. This significantly increases the total amount of stray light collected, improves the power detection signal strength, and reduces detection errors caused by ambient light interference.

[0009] Preferably, the semiconductor laser chip has a fast-axis collimating lens in its output optical path. The semiconductor laser chip has a large fast-axis divergence angle, and the fast-axis collimating lens can correct the diverging beam into parallel light, significantly reducing beam divergence loss. Combined with the rear cylindrical lens, it achieves bidirectional beam shaping, improving overall light energy utilization and reducing energy waste.

[0010] Preferably, the laser body has a positioning seat at the light-emitting end and an interface at the light-input end of the beam switching head. The positioning seat and the interface are detachably connected by a snap-fit ​​or magnetic attraction. This allows for rapid switching between different beam sizes, adapting to various treatment areas such as the face, limbs, and back, and reducing the time required for medical procedures.

[0011] Preferably, the positioning base is further provided with a positioning pin, and the interface is provided with a positioning hole corresponding to the position of the positioning pin. When the laser body is docked with the beam switching head, the positioning pin is inserted into the positioning hole. The positioning pin and the positioning hole form a coaxial limiting structure, which ensures that the optical path is accurately aligned each time the beam switching head is replaced, avoiding beam distortion and light energy loss caused by disassembly and assembly misalignment, and ensuring the consistency of beam output after multiple disassembly and assembly.

[0012] Preferably, the cylindrical lenses in each spot switching head have different fast and slow axis compression ratios, and the output window size of each spot switching head is different; the input end size of each spot switching head is the same and matches the output end of the laser body. A standardized and unified input interface allows the same laser body to use multiple switching heads with different compression ratios and output windows; simply changing the switching head allows for the output of spot sizes with varying dimensions.

[0013] Preferably, the laser body also includes a light-transmitting septum located in front of the photodetector's detection direction. The septum filters out stray light from the workshop environment and scattered interference light from the treatment area, allowing only specific wavelengths of laser light reflected from the skin to pass through, thus eliminating interference from external light on power detection and further improving the photodetector's detection accuracy.

[0014] Preferably, the cylindrical lens is a plano-convex cylindrical lens, with its generatrix direction aligned with the fast axis direction of the semiconductor laser chip. This effectively compresses the remaining divergent beam along the fast axis, and, in conjunction with a front-end fast-axis collimating lens, further optimizes the parallelism of the fast-axis beam, adapting to the beam shaping requirements of small-sized, fine treatment spots, resulting in clear spot edges and uniform energy distribution.

[0015] Preferably, the cylindrical lens is a biconvex cylindrical lens, with its generatrix direction aligned with the slow axis direction of the semiconductor laser chip. This biconvex structure efficiently compresses the long-span slow-axis beam, adapting to large-area, large-size treatment spot shaping, improving the light energy focusing effect under large spot sizes, and enhancing the efficiency of large-area hair removal and physiotherapy procedures.

[0016] As can be seen from the above technical solutions, the beneficial effects of this utility model are as follows: This solution, by setting a surrounding quadrangular truncated reflector inside the beam switching head, with the small end close to the light outlet and the large end facing the cylindrical lens, not only avoids blocking the outward output main treatment beam but also completely gathers stray light reflected back from the skin. This prevents stray light from damaging the semiconductor laser chip by back-impacting it and also directs the stray light to the photodetector. The photodetector collects the stray light signal and transmits it to the control circuit board, allowing the system to determine the actual laser power and perform adjustment compensation to stabilize the beam output energy. Inside the switching head, the cylindrical lens is arranged on the side of the reflector closest to the laser. The cylindrical lens compresses and shapes the incident laser, improving the concentration of light energy, while the reflector intercepts all back-scattered stray light, achieving beam shaping and optical path protection without interference. A fast-axis collimating lens is added to the chip's output optical path to correct the large divergence of the fast-axis beam, working in conjunction with the cylindrical lens to complete bidirectional beam shaping, effectively reducing beam divergence loss and improving light energy utilization. High efficiency; the laser and switching head adopt a snap-on or magnetic quick-release structure with a positioning pin and positioning hole coaxial limiting structure, allowing for quick disassembly and replacement of the switching head without tools. At the same time, each assembly ensures precise alignment of the optical path, eliminating spot distortion and light energy loss caused by disassembly and assembly misalignment. The spot output performance remains consistent after multiple replacements; all switching heads use a unified specification input interface. By simply changing the internal cylindrical lenses with different compression ratios and different sizes of light output windows, various specifications of light spots can be output, making the whole machine highly versatile; a light-transmitting septum is added to the front end of the photodetector to filter out ambient stray light interference, allowing only the reflected light of the target wavelength to pass through, improving the power detection accuracy; plano-convex cylindrical lenses are adapted for fast-axis shaping to meet the needs of fine small spot use, while biconvex cylindrical lenses efficiently compress slow-axis beams and are suitable for large-area physical therapy and hair removal scenarios. The two types of cylindrical lenses can be matched with different clinical conditions, taking into account the ease of disassembly and assembly, beam utilization efficiency, optical path protection safety, real-time controllability of output power, and multi-scenario adaptability. Attached Figure Description

[0017] To more clearly illustrate the technical solution of this patent, the drawings used in the description will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this patent. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a structural schematic diagram of a specific embodiment of the present utility model.

[0019] Figure 2 This is a schematic diagram of the laser body in a specific embodiment of the present invention.

[0020] Figure 3 This is a schematic diagram of the beam switching head in a specific embodiment of the present invention.

[0021] Figure 4 This is a schematic diagram of the reflector structure in a specific embodiment of the present invention.

[0022] Explanation of main figure symbols 1. Laser body, 2. Semiconductor laser chip, 3. Fast axis collimating lens, 4. Control circuit board, 5. Identification module, 6. Light-transmitting partition, 7. Positioning pin, 8. Photodetector, 9. Positioning seat, 10. Interface, 11. Reflector, 12. Cylindrical lens, 13. Electronic tag, 14. Switching head housing, 15. Light output window, 16. Beam switching head. Detailed Implementation

[0023] To make the objectives, features, and advantages of this patent more apparent and understandable, the technical solutions of this patent will be clearly and completely described below with reference to the accompanying drawings of the specific embodiments. Obviously, the embodiments described below are only some embodiments of this patent, and not all embodiments. Based on the embodiments of this patent, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this patent.

[0024] like Figures 1 to 4As shown, this embodiment discloses a semiconductor laser capable of rapidly switching beam spots. The complete device consists of a laser body 1 and multiple detachable beam spot switching heads 16. Each beam spot switching head 16 is equipped with a switching head housing 14 as an external support structure. One end of the switching head housing 14 is connected to the laser body 1, and the other end of the switching head housing 14 away from the laser body 1 has an output window 15 for laser output. A cylindrical lens 12 is assembled inside the switching head housing 14 near the laser body 1. The cylindrical lens 12 can be a plano-convex cylindrical lens with a busbar matching the fast axis of the semiconductor laser chip 2. The beam is compressed and shaped in the corresponding dimension by different types of cylindrical lenses, either a surface lens or a biconvex cylindrical lens that matches the slow axis of the semiconductor laser chip 2. A reflector 11 is installed around the inner wall of the switching head housing 14 between the cylindrical lens 12 and the light output window 15. The reflector 11 adopts an internally penetrating quadrangular frustum structure. The small end of the reflector 11 is arranged facing the light output window 15. The reflector 11 can collect stray light that is diffusely reflected from the skin and reflected back into the switching head housing 14 and reflect it in a directional manner. The inner diameter of the reflector 11 is larger than the diameter of the main beam after shaping, so it will not block the outward output of the treatment laser. The inner cavity of the laser body 1 is arranged with a semiconductor laser chip 2, a control circuit board 4, and a photodetector 8. A fast-axis collimating lens 3 is fixedly installed on the output light path of the semiconductor laser chip 2. The fast-axis collimating lens 3 pre-corrects the large divergence angle beam of the chip. The photodetector 8 is arranged on the reflected light path of the reflector 11. A light-transmitting stencil 6 is installed in front of the photodetector 8 inside the laser body 1 to filter environmental interference stray light. The photodetector 8 and the semiconductor laser chip 2 are electrically connected to the control circuit board 4 through circuits. After receiving the stray light converged by the reflector 11, the photodetector 8 outputs a corresponding electrical signal. The control circuit board calculates the real-time output power based on the electrical signal to realize online power monitoring and automatic compensation.

[0025] The laser body 1 has a positioning seat 9 at its output end, and an interface 10 is provided at the input end of the laser body 1. The positioning seat 9 and the interface 10 are connected by a snap-fit ​​or magnetic structure for tool-free quick assembly and disassembly. Positioning pins 7 are fixedly installed on the positioning seat 9, and positioning holes that match the positioning pins 7 are opened inside the interface 10. When assembling the beam switcher 16, the positioning pins 7 are fully inserted into the positioning holes to constrain the beam switcher 16 and the laser body 1 to be coaxial, thus preventing beam distortion and light energy loss caused by misalignment during assembly and disassembly. All beam switchers 16 have a standardized input end size and can be adapted to the positioning seat 9 of the same laser body 1. The cylindrical lenses 12 inside the beam switchers 16 of different specifications are set with different fast and slow axis compression ratios. At the same time, each beam switcher 16 is equipped with an output window 15 of different sizes. By simply changing the beam switcher 16, large, medium and small treatment beams can be output to meet the needs of different treatment areas such as the face, limbs and back.

[0026] When the device is working, the light beam emitted by the semiconductor laser chip 2 first passes through the fast-axis collimating lens 3 to complete fast-axis parallelization correction. After entering the beam switching head 16, the beam is compressed and shaped by the cylindrical lens 12. The shaped laser then passes through the central channel of the reflector 11 and shines onto the skin surface through the light output window 15. When the laser shines on the skin, some light energy is absorbed, and some light energy undergoes diffuse reflection, forming stray light that is reflected back into the beam switching head. This stray light enters the beam switching head 16 from the light output window 15 and is collected and reflected by the reflector 11 located on the inner wall of the switching head housing 14. The conical structure of the reflector 11 converges and reflects the stray light to the photodetector 8 located on the reflected light path.

[0027] The photodetector 8 (optionally BPW34SE9601) converts the received optical signal into a current signal, which is then transmitted to the control circuit board 4 via a signal line. The control circuit board 4 converts the current signal into a corresponding optical power value according to a preset calibration curve. Since the intensity of stray light is positively correlated with the power of the emitted laser, the actual output power of the spot switch head 16 can be indirectly monitored by detecting the intensity of stray light.

[0028] The control circuit board 4 has an internal storage module that stores power calibration curves corresponding to various models of beam switching heads 16. The power calibration curves are obtained as follows: Under standard test conditions, the actual emitted power P at the light output window 15 of the beam switching head 16 is measured using a standard power meter. Simultaneously, the voltage signal V output by the photodetector 8 is acquired. Multiple sets of (V, P) data points are obtained by changing the laser drive current. A mapping relationship of P=f(V) is obtained through linear regression or piecewise interpolation fitting. The control circuit board 4 retrieves the corresponding calibration curve based on the currently identified beam switching head 16 model, and by substituting the real-time acquired voltage signal V into the curve equation, the current actual emitted power P can be obtained.

[0029] When the detected output power deviates from the preset range, the control circuit board 4 can adjust the drive current of the semiconductor laser chip 2 to compensate for the power deviation, or prompt the user to replace the spot switching head or clean the output window and cylindrical lens through an audible and visual alarm.

[0030] Each beam switching head 16 is also equipped with an electronic tag 13 (such as an RFID tag or an EEPROM chip), and the laser body 1 is equipped with an identification module 5 that works with the electronic tag 13. The identification module 5 is connected to the electronic tag 13 through a probe. When the beam switching head 16 is installed in place, the identification module 5 automatically reads the information such as the switching head model, beam size, and calibration coefficient stored in the electronic tag 13 through the probe. The control circuit board 4 then automatically calls up the corresponding operating parameters and power calibration curve accordingly.

[0031] This invention employs a fast-axis collimating lens and cylindrical lenses of different specifications to achieve bidirectional beam shaping, which can significantly compress the beam divergence angle of the semiconductor laser chip, reduce light energy loss, and improve the overall utilization rate of light energy. It uses a quick-release standardized interface, allowing for rapid replacement of the beam switching head without tools. Combined with the coaxial limiting structure of the positioning pin and positioning hole, precise optical path alignment is ensured with each assembly. The multi-specification series of beam switching heads features differentiated cylindrical lens compression ratios and output window sizes, allowing a single laser to output multiple beam sizes to suit different medical aesthetic treatment areas such as the face, limbs, and back, resulting in strong equipment versatility. The small opening of the truncated pyramid reflector inside the switching head faces the output window, effectively collecting diffuse stray light from the skin and preventing stray light from damaging the semiconductor laser chip, while not obstructing the main treatment beam, thus balancing optical path protection and normal light output. Requirements: Stray light gathered by the reflector is directed to the photodetector, and a front-mounted light-transmitting septum filters out ambient light interference. Actual output power can be indirectly detected without adding a beam splitter to the main optical path, eliminating main beam energy loss. The control circuit board pre-stores dedicated power calibration curves for each type of beam switching head. Combined with electronic tags and an identification module, it automatically identifies the current switching head model, matches the corresponding calibration parameters, and calculates accurate output power in real time. When lens contamination or component aging causes power attenuation, the system can automatically adjust the chip drive current to compensate for power or provide audible and visual alarms for maintenance. Real-time monitoring and intelligent control of output power are achieved throughout the process, effectively ensuring stable and consistent beam output energy under different operating conditions. The overall design balances ease of installation and removal, beam utilization efficiency, optical path operation safety, power detection accuracy, and multi-scenario adaptability, significantly reducing equipment usage and maintenance costs.

[0032] The above description of the disclosed embodiments enables those skilled in the art to implement or use this patent. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this patent. Therefore, this patent is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A semiconductor laser capable of rapidly switching beam spots, comprising a laser body (1) and multiple beam spot switching heads (16), characterized in that, The light spot switching head (16) includes a switching head housing (14), one end of which is connected to the laser body (1), and the other end is set as a light output window (15). The switching head housing (14) is also provided with a reflector (11), which is arranged around the inner wall of the switching head housing (14) to reflect stray light reflected back through the skin. The laser body (1) is provided with a semiconductor laser chip (2), a control circuit board (4) and a photodetector (8). The photodetector (8) and the semiconductor laser chip (2) are both electrically connected to the control circuit board (4). The photodetector (8) can receive stray light reflected by the reflector (11) and output corresponding electrical signals.

2. The semiconductor laser with rapidly switchable beam spot according to claim 1, characterized in that, A cylindrical lens (12) is provided inside the switching head housing (14) on the side near the laser body (1), and the reflector (11) is located between the cylindrical lens (12) and the light output window (15).

3. The semiconductor laser with rapidly switchable beam spot according to claim 1, characterized in that, The reflector (11) is a frustum-shaped structure with an internal through-hole, and the small end of the reflector (11) is located near the light-emitting window (15).

4. The semiconductor laser with rapidly switchable beam spot according to claim 1, characterized in that, The semiconductor laser chip (2) has a fast-axis collimating lens (3) on its light output path.

5. The semiconductor laser with rapidly switchable beam spot according to claim 1, characterized in that, The laser body (1) has a positioning seat (9) at the light-emitting end and an interface (10) at the light-input end of the light spot switching head (16). The positioning seat (9) and the interface (10) are detachably connected by a snap or magnetic attraction.

6. The semiconductor laser with rapidly switchable beam spot according to claim 5, characterized in that, The laser body (1) is also provided with a positioning pin (7), and the spot switching head (16) is provided with a positioning hole corresponding to the position of the positioning pin (7). When the laser body (1) and the spot switching head (16) are connected, the positioning pin (7) is inserted into the positioning hole.

7. The semiconductor laser with rapidly switchable beam spot according to claim 2, characterized in that, The cylindrical lens (12) in each spot switching head (16) has different fast and slow axis compression ratios, and the output window size of each spot switching head (16) is different; the input end size of each spot switching head (16) is the same and matches the output end of the laser body (1).

8. The semiconductor laser with rapidly switchable beam spot according to claim 1, characterized in that, The laser body (1) is also provided with a light-transmitting partition (6), which is located in front of the photodetector (8) in the detection direction.

9. The semiconductor laser with rapidly switchable beam spot according to claim 2, characterized in that, The cylindrical lens (12) is a plano-convex cylindrical lens, and its generatrix direction is consistent with the fast axis direction of the semiconductor laser chip (2).

10. The semiconductor laser with rapidly switchable beam spot according to claim 2, characterized in that, The cylindrical lens (12) is a biconvex cylindrical lens, and its generatrix direction is consistent with the slow axis direction of the semiconductor laser chip (2).

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