Device and method for acquiring micro-size pulse laser beam

Abstract

The invention relates to a device and a method for acquiring a micro-size pulse laser beam, and belongs to the technical field of laser. The invention aims to solve the challenges of a traditional all-solid-state laser in the aspects of realizing micro-size light beams and high-efficiency output power. The device adopts a micro-size cavity mirror structure, and realizes flexible output of micro-size laser beams with different radiuses by adjusting the size of the cavity mirror and the configuration of the resonant cavity. Meanwhile, spontaneous radiation amplification light generated by a high-gain module is utilized, and a micro-size small-hole diaphragm is ingeniously added into the resonant cavity, so that precise superposition of a spontaneous radiation light path and a resonant cavity oscillation starting light path is realized, light path configuration is optimized, oscillation starting of the resonant cavity is effectively promoted, and therefore, a high-quality micro-size laser beam is output. Different from a scheme of clamping light by relying on an extra-cavity small-hole diaphragm, a breakthrough of laser beam miniaturization is realized through close fit of the built-in micro-size small-hole diaphragm and the micro-cavity mirror, and the device is simpler and more efficient in structure.

Description

Technical Field

[0001] The invention belongs to the field of laser technology and relates to a device and a method for obtaining a micro-size pulse laser beam. Background Art

[0002] With the continuous development of laser technology, all-solid-state lasers have been widely used in laser guidance, scientific research and other fields due to their high luminous efficiency, wide spectral range, compact structure and excellent seismic resistance.

[0003] However, conventional all-solid-state lasers face challenges in achieving micro-sized beams and high-efficiency output:

[0004] 1. Micro-sized beams are difficult to output stably

[0005] The traditional method is to reduce the beam size by inserting a small hole aperture, but this will induce diffraction effects, resulting in increased losses and making it difficult to achieve stable output of micro-sized beams.

[0006] The position and size of the pinhole aperture have a significant impact on the beam quality and require precise control, which increases system complexity and cost.

[0007] 2. It is difficult to balance output power and mode stability

[0008] The traditional method is to increase the output power by shortening the resonant cavity length, but this may lead to mode instability and affect the laser quality.

[0009] Although long-cavity lasers have high mode stability, their output power is usually low and they are susceptible to losses.

[0010] 3. Existing solutions have limitations

[0011] Microcavity laser: Utilizing the resonance effect of the microcavity structure, micro-sized beam output can be achieved, but the power is usually low and it is difficult to meet the needs of high-power applications.

[0012] Multi-beam synthesis technology: combining multiple laser beams into one beam can increase the output power, but the beam quality is difficult to guarantee and beam distortion and noise are prone to occur.

[0013] 4. The need for miniaturized, high-power, high-quality lasers

[0014] With the rapid development of micromachining, biomedicine, optical communications and other fields, the demand for miniaturized, high-power, and high-quality lasers is growing.

[0015] However, existing all-solid-state lasers are difficult to meet these requirements, and there is an urgent need to develop new technical solutions. Summary of the invention

[0016] In view of this, an object of the present invention is to provide a device and method for obtaining a micro-sized pulsed laser beam.

[0017] In order to achieve the above object, the present invention provides the following technical solutions:

[0018] A device for obtaining a micro-sized pulsed laser beam, comprising:

[0019] A first micro-sized reflector, used for reflecting the laser beam;

[0020] A second micro-sized reflector, used for reflecting the laser beam;

[0021] A laser optical path component is disposed between the first micro-size reflector and the second micro-size reflector and is used to generate a laser beam;

[0022] A first micro-sized pinhole aperture is disposed in the laser light path and is used to spatially limit the laser beam;

[0023] A second micro-sized pinhole aperture is disposed in the laser light path and is used to spatially limit the laser beam;

[0024] The first micro-sized reflector and the second micro-sized reflector constitute a resonant cavity, and the first micro-sized pinhole diaphragm and the second micro-sized pinhole diaphragm are arranged inside the resonant cavity.

[0025] Furthermore, the laser optical path component includes a Q-switching component and a high-gain module.

[0026] Furthermore, the Q-switching component includes a KD*P crystal, a λ / 4 wave plate and a polarizer.

[0027] Furthermore, the high-gain module has strong spontaneous radiation amplification light characteristics, its pumping mode is side pumping or end pumping, and the working material includes Nd:YAG crystal, Nd:YLF crystal, Nd:KGW crystal and Nd:YVO4 crystal.

[0028] Furthermore, the first micro-size reflector and the second micro-size reflector have an overall diameter of 12.7 mm and include a plurality of micro-mirrors, and the diameter of the micro-mirrors ranges from 10 μm to 4000 μm.

[0029] Furthermore, there is no strict restriction on the aperture sizes of the first micro-sized pinhole diaphragm and the second micro-sized pinhole diaphragm, but they need to be slightly larger than the size of the micro-cavity mirror.

[0030] Furthermore, it also includes a first indicating light source and a second indicating light source, which are used to collimate the first micro-sized reflector and the second micro-sized reflector respectively.

[0031] Furthermore, the device for acquiring a micro-sized pulsed laser beam also includes a first six-dimensional adjustment frame and a second six-dimensional adjustment frame, which are used to adjust the pitch and yaw of the first micro-sized reflector and the second micro-sized reflector, respectively.

[0032] A method for obtaining a micro-sized pulsed laser beam comprises the following steps:

[0033] Using the first indicating light source to collimate the first micro-sized reflector, so that the collimated light passes through the first micro-sized reflector and enters the pinhole aperture;

[0034] collimating the second micro-size reflector by using the second indicating light source, so that the collimated light passes through the second micro-size reflector and enters the pinhole aperture;

[0035] Adjust the parameters of the Q-switching component and the high-gain module so that the laser beam oscillates through the resonant cavity;

[0036] The angles of the first micro-sized reflecting mirror and the second micro-sized reflecting mirror are adjusted so that the laser beam is output from the second micro-sized reflecting mirror.

[0037] Further, the method further comprises the following steps:

[0038] A first micro-sized pinhole diaphragm and a second micro-sized pinhole diaphragm are arranged in the laser light path to spatially limit the laser beam;

[0039] The first and second micro-sized pinhole diaphragms are collimated using the first and second indicator light sources.

[0040] The beneficial effects of the present invention are as follows: First, the present invention adopts a micro-sized cavity mirror structure, and by adjusting the cavity mirror size and the resonant cavity configuration, the flexible output of micro-sized laser beams of different radii is achieved, opening up a new path for the miniaturization of laser beams. Secondly, the spontaneous radiation amplification light generated by the high-gain module is used to accurately adjust the position of the output mirror, and at the same time, a micro-sized pinhole aperture is cleverly added to the resonant cavity so that the spontaneous radiation light path and the resonant cavity oscillation light path are precisely coincident. This design not only optimizes the optical path configuration, but also effectively promotes the resonant cavity oscillation based on the micro-cavity mirror, thereby outputting high-quality micro-sized laser beams. Unlike the traditional solution that relies on the pinhole aperture card outside the cavity, the present invention achieves a breakthrough in the miniaturization of laser beams through the close cooperation of the built-in micro-sized pinhole aperture and the micro-cavity mirror, and the device structure is simpler and more efficient. In addition, by flexibly adjusting the parameters of the micro-cavity mirror and the pinhole aperture, micro-sized laser beams of different specifications can be output to meet the needs of various application scenarios, showing extremely high practical value and innovative significance.

[0041] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below in conjunction with the accompanying drawings, wherein:

[0043] Figure 1 Provided is a preferred embodiment of the present invention, a device and method for obtaining a micro-sized pulsed laser beam;

[0044] Figure 2 It is a schematic diagram of the six-dimensional adjustment frame;

[0045] Figure 3 Schematic diagram of a micro-sized reflector.

[0046] Figure numerals: first indication light source 1, first micro-size reflector 2, Q-switching component 3, laser optical path component 4, KD*P crystal 5, λ / 4 wave plate 6, polarizer 7, high gain module 8, second micro-size reflector 9, second indication light source 10, first six-dimensional adjustment frame 11, second six-dimensional adjustment frame 12. DETAILED DESCRIPTION

[0047] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0048] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0049] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "rear", etc. indicate the orientation or position relationship, they are based on the orientation or position relationship shown in the drawings, which is 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 operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0050] See also Figure 1 to Figure 3 A device for obtaining a micro-sized pulsed laser beam, the device comprising a first micro-sized reflector 2, a laser optical path component 4 and a second micro-sized reflector 9, the first micro-sized reflector 2 and the second micro-sized reflector 9 form a resonant cavity, the first indicating light source 1 and the second indicating light source 10 serve as a debugging benchmark for the overall optical path, and provide a standard for the alignment of each device; the first micro-sized pinhole diaphragm S1, the second micro-sized pinhole diaphragm S2, the third micro-sized pinhole diaphragm S3, and the fourth micro-sized pinhole diaphragm S4 are respectively arranged at different positions of the laser optical path, for precise spatial limitation of the laser beam.

[0051] Preferably, in the device for obtaining a micro-sized pulsed laser beam, the laser optical path component 4 includes a Q-switching component 3 and a high-gain module 8 .

[0052] Preferably, in the device for obtaining a micro-size pulsed laser beam, the Q-switching component includes a KD*P crystal 5, a λ / 4 wave plate 6 and a polarizer 7; the high-gain module 8 is a laser module with strong spontaneous radiation amplification characteristics, and its pumping method can be side pumping or end pumping. The working material includes Nd:YAG crystal, Nd:YLF crystal, Nd:KGW crystal, Nd:YVO4 crystal and other laser crystals. The module operates in a pulsed mode and outputs pulsed laser.

[0053] Preferably, in the device for obtaining a micro-sized pulsed laser beam, the KD*P crystal 5 is used for nonlinear modulation, and the refractive index of the crystal is adjusted by applying an electric field, thereby controlling the phase and polarization of the laser, and further optimizing the pulse characteristics of the laser output; the λ / 4 wave plate 6 adjusts the polarization state of the light beam; and the polarizer 7 selectively transmits according to the polarization direction of the light beam, allowing only the required polarized light to pass through, so as to achieve high-quality pulsed laser output.

[0054] Preferably, in the device for obtaining a micro-size pulsed laser beam, the overall diameter of the first micro-size reflector 2 and the second micro-size reflector 9 is 12.7 mm, comprising a plurality of micro-mirrors with a mirror diameter ranging from 10 μm to 4000 μm; the surface thereof is coated with a high-reflection film with a reflectivity exceeding 99%, and the pitch and yaw are fixed and adjusted by a first six-dimensional adjustment frame 11 and a second six-dimensional adjustment frame 12 respectively.

[0055] Preferably, in the device for obtaining a micro-size pulsed laser beam, the first six-dimensional adjustment frame 11 and the second six-dimensional adjustment frame 12 are made of aluminum alloy material, have adjustment functions in the X-axis, Y-axis and Z-axis directions, wherein the coarse adjustment resolution is 0.01mm, the fine adjustment resolution is 0.0005mm, the total travel range is ±6.5mm, and the driving mode is a differential head.

[0056] Preferably, in the device for obtaining a micro-size pulsed laser beam, the first indication light source 1 and the second indication light source 10 may be light sources including but not limited to gas lasers, solid lasers and semiconductor lasers, which have stable wavelengths, high beam quality, moderate output power and are suitable for indication.

[0057] Preferably, in the device for obtaining a micro-sized pulsed laser beam, the first micro-sized pinhole aperture S1, the second micro-sized pinhole aperture S2 and the first indicator light source 1 are respectively located at two ends of the first micro-sized reflector 2, and the angle of the first micro-sized reflector 2 is adjusted by a first six-dimensional adjustment frame 11 so that the collimated light passes through the reflector and enters the two pinhole apertures; then the third micro-sized pinhole aperture S3, the fourth micro-sized pinhole aperture S4 and the light of the first indicator light source 1 passing through the first micro-sized pinhole aperture S1 and the second micro-sized pinhole aperture S2 are used to collimate the second indicator light source 10; then the second micro-sized reflector 9 is added so that the light energy of the second indicator light source 10 passes through the second micro-sized reflector 9 and enters the third micro-sized pinhole aperture S3 and the fourth micro-sized pinhole aperture S4.

[0058] Preferably, in the device for obtaining a micro-size pulsed laser beam, the aperture sizes of the first micro-size pinhole diaphragm S1, the second micro-size pinhole diaphragm S2, the third micro-size pinhole diaphragm S3, and the fourth micro-size pinhole diaphragm S4 are not strictly limited, but need to be slightly larger than the size of the microcavity mirror, and their materials are selected from metals or ceramics with high thermal conductivity to ensure heat dissipation performance and optical stability.

[0059] Preferred embodiment 1

[0060] As a preferred embodiment, the indicator light source is a He-Ne laser, the high-gain module adopts a side three-way pumping structure, the gain medium is a Nd:YAG crystal, and the electro-optical Q-switched crystal is a KD*P crystal; the pump source works in a pulsed pumping mode; the micro-size pinhole aperture is made of ceramic material with an aperture of 300μm, and the aperture of the micro-size reflector is 300μm.

[0061] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separable, and the components shown as units may or may not be physical units, i.e., they may be located in one place or distributed over multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0062] In summary, this experiment successfully achieved the construction of a device and method for obtaining a micro-sized pulsed laser beam through a series of precise optical path debugging steps. First, by debugging the indicator light source, ensure that the first and second micro-sized pinhole apertures are at the same horizontal plane as the experimental platform to ensure the accuracy of the optical path. Then, the indicator light source is used to determine that the angle between the polarizer and the optical path is 45°, and the angle between the reflector and the optical path is adjusted according to the relative position of the light source and the pinhole aperture. Subsequently, by combining the high-gain module and the micro-sized aperture, the propagation path of the spontaneous radiation light of the high-gain module is determined. Next, the reflector and position are adjusted using the indicator light source and the pinhole aperture to ensure that they are at an angle of 45° with the optical path. Finally, a λ / 4 wave plate, a KD*P crystal, and the first micro-sized reflector are added to the debugged optical path, and the pitch and yaw of each device are further adjusted to successfully achieve the laser start-up of the high-gain long-cavity laser device based on the micro-cavity mirror. Through the fine debugging of these steps, the optimization of the laser beam size and power output is ensured.

[0063] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. A device for obtaining a micro-sized pulsed laser beam, characterized in that: include: A first micro-sized reflector, used for reflecting the laser beam; A second micro-sized reflector, used for reflecting the laser beam; A laser optical path component is disposed between the first micro-size reflector and the second micro-size reflector and is used to generate a laser beam; A first micro-sized pinhole aperture is disposed in the laser light path and is used to spatially limit the laser beam; A second micro-sized pinhole aperture is disposed in the laser light path and is used to spatially limit the laser beam; A third micro-sized pinhole aperture is disposed in the laser light path and is used to spatially limit the laser beam; A fourth micro-sized pinhole aperture is disposed in the laser light path and is used to spatially limit the laser beam; The first micro-size reflector and the second micro-size reflector form a resonant cavity, and the first micro-size pinhole diaphragm, the second micro-size pinhole diaphragm, the third micro-size pinhole diaphragm and the fourth micro-size pinhole diaphragm are arranged inside the resonant cavity.

2. The device for obtaining a micro-sized pulsed laser beam according to claim 1, characterized in that: The laser optical path component includes a Q-switching component and a high-gain module.

3. The device for obtaining a micro-sized pulsed laser beam according to claim 2, characterized in that: The Q-switching component includes a KD*P crystal, a λ / 4 wave plate and a polarizer.

4. The device for obtaining a micro-sized pulsed laser beam according to claim 3, characterized in that: The high-gain module has strong spontaneous radiation amplification light characteristics, and its pumping mode is side pumping or end pumping. The working material includes Nd:YAG crystal, Nd:YLF crystal, Nd:KGW crystal and Nd:YVO4 crystal.

5. The device for obtaining a micro-sized pulsed laser beam according to claim 1, characterized in that: The overall diameter of the first micro-size reflector and the second micro-size reflector is 12.7 mm, and they include a plurality of micro-mirrors, and the mirror diameter ranges from 10 μm to 4000 μm.

6. The device for obtaining a micro-sized pulsed laser beam according to claim 1, characterized in that: There is no strict restriction on the aperture sizes of the first micro-sized pinhole diaphragm and the second micro-sized pinhole diaphragm, but they need to be slightly larger than the size of the micro-cavity mirror.

7. The device for obtaining a micro-sized pulsed laser beam according to claim 1, characterized in that: It also includes a first indicating light source and a second indicating light source, which are used to collimate the first micro-sized reflector and the second micro-sized reflector respectively.

8. The device for obtaining a micro-sized pulsed laser beam according to claim 1, characterized in that: The device for obtaining a micro-sized pulsed laser beam further comprises a first six-dimensional adjustment frame and a second six-dimensional adjustment frame, which are used to adjust the pitch and yaw of the first micro-sized reflector and the second micro-sized reflector respectively.

9. A method for obtaining a micro-sized pulsed laser beam, characterized in that: The following steps are involved: Using the first indicating light source to collimate the first micro-sized reflector, so that the collimated light passes through the first micro-sized reflector and enters the pinhole aperture; collimating the second micro-size reflector by using the second indicating light source, so that the collimated light passes through the second micro-size reflector and enters the pinhole aperture; Adjust the parameters of the Q-switching component and the high-gain module so that the laser beam oscillates through the resonant cavity; The angles of the first micro-sized reflecting mirror and the second micro-sized reflecting mirror are adjusted so that the laser beam is output from the second micro-sized reflecting mirror.

10. The method for obtaining a micro-sized pulsed laser beam according to claim 9, characterized in that: The following steps are also included: A first micro-sized pinhole diaphragm and a second micro-sized pinhole diaphragm are arranged in the laser light path to spatially limit the laser beam; The first and second micro-sized pinhole diaphragms are collimated using the first and second indicator light sources.

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