A high-energy laser for liquid crystal repair

Abstract

The present invention relates to a high-energy laser for liquid crystal repair, which comprises a semiconductor laser, a beam shaping element, a laser energy enhancement element, and a multi-frequency light output element arranged in sequence along the light propagation direction; the semiconductor laser is used for emitting semiconductor laser light; the beam shaping element is used for adjusting the beam energy distribution of the semiconductor laser light to a flat-top distribution; the laser energy enhancement element is used for enhancing the energy of the semiconductor laser light and outputting fundamental frequency light; the multi-frequency light output element is used for performing frequency conversion on the fundamental frequency light to output mixed light containing multiple wavelengths and adjusting the proportion of light of each wavelength. The present invention can reduce the concentration of the high-energy laser energy distribution, thereby reducing the damage to optical elements, increasing the service life of optical elements, reducing the maintenance frequency, and reducing costs; and can output mixed light of multiple wavelengths and adjust the proportion of light of each wavelength to meet different energy ratio requirements and improve the scope of application.

Description

Technical Field

[0001] The present invention relates to the technical field of lasers, and in particular to a high-energy laser for liquid crystal repair. Background Art

[0002] During the manufacturing process of liquid crystal panels or OLED panels, due to process complexity and material characteristics, defects such as bright spots, dark spots, and flash points will occur. When laser is irradiated onto the defective pixel area of the liquid crystal or OLED panel, the thermal effect generated by the laser will locally soften or change the material structure between the color film and the glass substrate, as well as part of the structure of the black matrix, thereby repairing the working performance of the pixel. Since the thermal effects generated by lasers of different wavelengths during repair are different, lasers of different wavelengths will be selected for different defect types. A high-energy laser that outputs multiple wavelengths simultaneously has become an ideal light source in the field of liquid crystal repair. To obtain high-energy laser output, LD or pulsed xenon lamps are usually used to pump the laser gain medium from the side. This solution has low energy conversion efficiency and high waste heat, and usually requires circulating water cooling to reduce it. When using the slab method, there are problems such as difficult crystal processing, high cost, and the need for a complex shaping system to shape the linear light spot into a circular light spot, making the system complex and not easy for mass production. When using the end-pumping scheme, the crystal has strong absorption, high conversion efficiency, and high beam quality. However, the light output from the LD fiber coupling module is Gaussian distribution. After being shaped by a traditional spherical lens and focused into the laser crystal, it is still Gaussian distribution, with the energy concentrated in the central region, resulting in Gaussian distribution of the infrared laser output, too concentrated energy, causing damage to the optical components in the cavity, reducing the laser life, requiring high-frequency maintenance, and high maintenance costs. The above problems need to be solved urgently. Summary of the Invention

[0003] The present invention discloses a high-energy laser for liquid crystal repair, aiming to solve the technical problems existing in the prior art.

[0004] The present invention adopts the following technical solutions:

[0005] The present invention provides a high-energy laser for liquid crystal repair, which includes a semiconductor laser, a beam shaping element, a laser energy enhancement element, and a multi-frequency light output element arranged in sequence along the light propagation direction; the semiconductor laser is used to emit semiconductor laser; the beam shaping element is used to adjust the beam energy distribution of the semiconductor laser to a flat-top distribution; the laser energy enhancement element is used to enhance the energy of the semiconductor laser and output fundamental frequency light; the multi-frequency light output element is used to perform frequency conversion on the fundamental frequency light to output a mixed light containing multiple wavelengths and adjust the proportion of light of each wavelength.

[0006] In the high-energy laser for liquid crystal repair of the present invention, the beam shaping element includes a collimating mirror and a focusing mirror; the collimating mirror and the focusing mirror are arranged in sequence along the light propagation direction, and both are aspherical lenses.

[0007] In the high-energy laser for liquid crystal repair of the present invention, the focal length ratio of the collimating mirror to the focusing mirror is 1:5 - 1:10.

[0008] In the high-energy laser for liquid crystal repair of the present invention, the laser energy enhancement element includes a Q-switching element and a laser crystal; the Q-switching element is used to enhance the energy of the semiconductor laser to generate giant pulse laser output; the laser crystal is used to convert the high-energy semiconductor laser output by the Q-switching element into fundamental frequency light.

[0009] In the high-energy laser for liquid crystal repair of the present invention, the laser energy enhancement element further includes a first reflecting mirror, an output mirror and a total reflecting mirror; the first reflecting mirror is used to transmit the semiconductor laser into the Q-switching element; the total reflecting mirror is used to reflect the high-energy semiconductor laser output by the Q-switching element into the Q-switching element, and then after being reflected by the first reflecting mirror again, it enters the laser crystal; the output mirror is arranged on the light output side of the laser crystal and is used to reflect a part of the fundamental frequency light output by the laser crystal and transmit the other part out.

[0010] In the high-energy laser for liquid crystal repair of the present invention, the laser energy enhancement element further includes a polarization element and a quarter-wave plate; the polarization element and the quarter-wave plate are arranged in sequence on the optical path between the first reflecting mirror and the Q-switching element; the polarization element is used to convert the fundamental frequency light into horizontally polarized linearly polarized light and reflect the fundamental frequency light reflected by the total reflecting mirror to the outside; the quarter-wave plate is used to rotate the polarization direction of the fundamental frequency light by 45°; the Q-switching element is also used to rotate the polarization direction of the fundamental frequency light.

[0011] In the high-energy laser for liquid crystal repair of the present invention, the first reflecting mirror is a plane mirror, arranged at an angle of 45° with the optical axis, with antireflection films for semiconductor laser coated on both sides, and a high-reflection film for fundamental frequency light is also coated on the side close to the laser crystal.

[0012] In the high-energy laser for liquid crystal repair of the present invention, the polarization element is a fundamental frequency light polarizer, arranged at the Brewster angle of the fundamental frequency light in the horizontal direction of the optical axis, and coated with an antireflection film in the horizontal direction and a high-reflection film in the vertical direction.

[0013] In the high-energy laser for liquid crystal repair of the present invention, the total reflecting mirror is a plano-concave mirror, with the concave surface facing the Q-switching element, and the radius of curvature of the total reflecting mirror is 500 - 1000 mm.

[0014] In the high-energy laser for liquid crystal repair of the present invention, the output mirror is a plane mirror, with a fundamental frequency partial reflection film coated on the side facing the laser crystal and an anti-reflection film for fundamental frequency light coated on the other side.

[0015] In the high-energy laser for liquid crystal repair of the present invention, the Q-switching element is an electro-optic Q-switching element.

[0016] In the high-energy laser for liquid crystal repair of the present invention, the multi-frequency light output element at least includes a plurality of first frequency doubling crystals and a plurality of second frequency doubling crystals; the lengths of the plurality of first frequency doubling crystals are different from each other, and they can be respectively switched to the light path of the laser energy enhancement element; the lengths of the plurality of second frequency doubling crystals are different from each other, and they can be respectively switched to the light path of the first frequency doubling crystal.

[0017] In the high-energy laser for liquid crystal repair of the present invention, the first frequency doubling crystal is a second harmonic generation crystal, and it can perform type-I or type-II critical phase matching or non-critical phase matching.

[0018] In the high-energy laser for liquid crystal repair of the present invention, the second frequency doubling crystal is a fourth harmonic generation crystal, and it can perform type-I critical phase matching; alternatively, the second frequency doubling crystal is a third harmonic generation crystal, and it can perform type-II critical phase matching.

[0019] In the high-energy laser for liquid crystal repair of the present invention, the first frequency doubling crystal and the second frequency doubling crystal are arranged close to the light output side of the laser energy enhancement element.

[0020] The technical solution adopted by the present invention can achieve the following beneficial effects:

[0021] The present invention mainly provides a high-energy laser for liquid crystal repair. Based on shaping the laser output by a semiconductor laser with a beam shaping element to output a laser beam with a flat-topped energy distribution curve, and then enhancing the energy of the laser with a laser energy enhancement element, it can reduce the concentration of the high-energy laser energy distribution, make the beam energy distribution uniform, thereby reducing the damage to optical elements, increasing the service life of optical elements, reducing the maintenance frequency, and reducing costs; moreover, the frequency of the input laser is adjusted with a multi-frequency light output element to output a mixed light of multiple wavelengths and adjust the proportion of each wavelength of light to meet different energy ratio requirements and improve the applicable range. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. These drawings form a part of the present invention. The schematic embodiments of the present invention and their explanations explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0023] Figure 1 This is a schematic structural diagram of a high-energy laser for liquid crystal repair according to the present invention.

[0024] Description of the reference numerals in the drawings:

[0025] 1. Semiconductor laser; 2. Beam shaping element; 21. Collimating mirror; 22. Focusing mirror; 3. Laser energy enhancement element; 31. Q-switching element; 32. Laser crystal; 33. First reflector; 34. Output mirror; 35. Total reflector; 36. Polarizing element; 37. Quarter-wave plate; 4. Multi-frequency light output element; 41. First frequency doubling crystal; 42. Second frequency doubling crystal. Specific embodiments

[0026] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments of the present invention and the corresponding drawings. In the description of the present invention, it should be noted that the term "or" is generally used in the sense of including "and / or", unless otherwise clearly specified in the content.

[0027] In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, a magnetic connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood in specific situations. In addition, in the description of this application, the terms "first", "second", etc. are only used for distinguishing descriptions, and cannot be understood as indicating or implying relative importance. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three or more, etc., unless otherwise clearly and specifically defined.

[0028] Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0029] To solve the problems existing in the prior art, the embodiments of this application provide a high-energy laser for liquid crystal repair.

[0030] As Figure 1As shown in the figure, a high-energy laser for liquid crystal repair includes a semiconductor laser 1, a beam shaping element 2, a laser energy enhancement element 3, and a multi-frequency light output element 4 arranged in sequence along the light propagation direction; the semiconductor laser 1 is used to emit semiconductor laser light; the beam shaping element 2 is used to adjust the beam energy distribution of the semiconductor laser light to a flat-top distribution, specifically to shape a Gaussian beam into a flat-top beam distribution, with uniform spot energy distribution and no strong points; the laser energy enhancement element 3 is used to enhance the energy of the semiconductor laser light and output fundamental frequency light; the multi-frequency light output element 4 is used to perform frequency conversion on the fundamental frequency light to output a mixed light containing multiple wavelengths and adjust the proportion of light of each wavelength.

[0031] A high-energy laser for liquid crystal repair according to the present invention is based on shaping the laser light output by the semiconductor laser 1 with the beam shaping element 2 to output a laser beam with a flat-top curve energy distribution curve, and then enhancing the energy of the laser with the laser energy enhancement element 3, which can reduce the concentration of the energy distribution of high-energy laser light, with uniform beam energy distribution, thereby reducing the damage to optical elements, increasing the service life of optical elements, reducing the maintenance frequency, and reducing costs; moreover, the laser input by the multi-frequency light output element 4 is frequency-adjusted to output a mixed light of multiple wavelengths and adjust the proportion of light of each wavelength to adapt to different energy ratio requirements and increase the applicable range.

[0032] In some preferred embodiments, the semiconductor laser 1 can be selected as a fiber-coupled semiconductor laser capable of outputting pulses at 808 nm, 878 nm, 885 nm, 888 nm, and 914 nm, and is temperature-controlled by a semiconductor refrigeration chip, with the output frequency adjustable in the range of 1 Hz - 100 Hz and a single-pulse energy of 50 mJ.

[0033] In some preferred embodiments, the semiconductor laser 1 is connected to the beam shaping element 2 through an optical fiber; the core diameter of the optical fiber can be 100 μm, 200 μm, or 400 μm.

[0034] In some preferred embodiments, the semiconductor laser 1, the beam shaping element 2, the laser energy enhancement element 3, and the multi-frequency light output element 4 are all arranged on the same bottom plate to dissipate heat through conduction cooling, such as selecting a material with good heat dissipation performance, such as copper, etc.

[0035] In some preferred embodiments, the beam shaping element 2 includes a collimating mirror 21 and a focusing mirror 22; the collimating mirror 21 and the focusing mirror 22 are arranged in sequence along the light propagation direction, and both are aspherical lenses, such as being arranged with aspherical surfaces opposite to each other; preferably, the collimating mirror 21 and the focusing mirror 22 can be arranged to be close to or away from each other, that is, slidably connected to the bottom plate on which the collimating mirror 21 and the focusing mirror 22 are installed, whereby the size of the formed spot can be adjusted.

[0036] Preferably, both the collimating mirror 21 and the focusing mirror 22 are double-sidedly coated with an anti-reflection film for semiconductor lasers; thereby, the transmittance of the semiconductor laser is increased.

[0037] Preferably, the focal length ratio of the collimating mirror 21 and the focusing mirror 22 is 1:5 - 1:10; based on this, the range of spot size adjustment is larger.

[0038] In some preferred embodiments, the laser energy enhancement element 3 includes a Q-switching element 31 and a laser crystal 32; the Q-switching element 31 is used to enhance the energy of the semiconductor laser to generate high-power pulsed laser output; the laser crystal 32 is used to convert the high-energy semiconductor laser output by the Q-switching element 31 into fundamental frequency light.

[0039] Preferably, the laser crystal 32 can be selected from Yb:YAG crystal, Nd:YLF crystal, Nd:YVO4 crystal, Nd:GdVO4 crystal, Nd:YAG crystal, Nd:YAP crystal or other laser crystals, specifically selected according to the working conditions; the doping concentration is 0.1% - 0.5%, the size is 5mm×5mm×20mm or 5mm×5mm×30mm, or other sizes; both light-passing surfaces are coated with an anti-reflection film for semiconductor lasers and fundamental frequency light, and are installed on the crystal base by indium soldering.

[0040] In some preferred embodiments, the laser energy enhancement element 3 further includes a first reflecting mirror 33, an output mirror 34 and a total reflecting mirror 35; the first reflecting mirror 33 is used to transmit the semiconductor laser into the Q-switching element 31; the total reflecting mirror 35 is used to reflect the high-energy semiconductor laser output by the Q-switching element 31 into the Q-switching element 31, and then after being reflected by the first reflecting mirror 33 again, it enters the laser crystal 32; the output mirror 34 is arranged on the light output side of the laser crystal 32, and is used to reflect a part of the fundamental frequency light output by the laser crystal 32 and transmit the other part out; an oscillation circuit is formed by the output mirror 34 and the total reflecting mirror 35, thereby increasing the energy accumulation of the Q-switching element 31 and further increasing the laser energy.

[0041] Preferably, the laser energy enhancement element 3 further includes a polarization element 36 and a quarter-wave plate 37; the polarization element 36 and the quarter-wave plate 37 are sequentially arranged on the optical path between the first reflecting mirror 33 and the Q-switching element 31; the polarization element 36 is used to convert the fundamental frequency light into horizontally polarized linearly polarized light, and reflect the fundamental frequency light reflected by the total reflecting mirror 35 to the outside. Based on the two actions of the quarter-wave plate 37, the horizontally polarized fundamental frequency light is converted into vertically polarized light, and then is reflected to the outside by the polarization element 36 to avoid the oscillation of the fundamental frequency light; the quarter-wave plate 37 is used to rotate the polarization direction of the fundamental frequency light by 45°; the Q-switching element 31 is also used to rotate the polarization direction of the fundamental frequency light. Based on this, the fundamental frequency light after increasing the energy will not be reflected by the polarization element 36; the polarization element 36 and the quarter-wave plate 37 cooperate to export the fundamental frequency light, achieving the effects of high gain and low loss.

[0042] Preferably, a second reflector 38 is further included; the second reflector 38 is used to reflect the light reflected by the first reflector 33 into the polarization element 36; in this way, it is more convenient to arrange each element. Further preferably, the second reflector 38 is a plane mirror, arranged at an angle of 45° with the optical axis, and the reflecting surface is coated with a high-reflection film for fundamental frequency light.

[0043] Preferably, the Q-switching element 31 can output laser with an adjustable frequency in the range of 1 - 100 Hz, an energy greater than 10 mJ, and a pulse width less than 10 ns.

[0044] Preferably, the Q-switching element 31 rotates the polarization direction of the fundamental frequency light through a longitudinal or transverse 1 / 4 wavelength voltage.

[0045] In some preferred embodiments, the first reflector 33 is a plane mirror, arranged at an angle of 45° with the optical axis, and both side surfaces are coated with an anti-reflection film for semiconductor laser, and the side surface close to the laser crystal 32 is further coated with a high-reflection film for fundamental frequency light.

[0046] Preferably, the polarization element 36 is a fundamental frequency light polarizer, arranged at the Brewster angle of the fundamental frequency light with the horizontal direction of the optical axis, and is coated with an anti-reflection film in the horizontal direction and a high-reflection film in the vertical direction.

[0047] Preferably, the total reflector 35 is a plano-concave mirror, with the concave surface facing the Q-switching element 31, and the radius of curvature of the total reflector 35 is 500 - 1000 mm; in this way, the stability of the resonant cavity can be effectively improved. Further preferably, the concave surface of the total reflector 35 is coated with a high-reflection film for fundamental frequency light laser.

[0048] Preferably, the output mirror 34 is a plane mirror, and the surface facing the laser crystal 32 is coated with a partial reflection film for fundamental frequency light, and the other surface is coated with an anti-reflection film for fundamental frequency light.

[0049] In some preferred embodiments, the Q-switching element 31 is an electro-optical Q-switching element. Optionally, the crystal type of the Q-switching element 31 is potassium dihydrogen phosphate (KDP) crystal, deuterated potassium dihydrogen phosphate (DKDP) crystal, lithium niobate crystal or barium metaborate crystal.

[0050] In some preferred embodiments, the multi-frequency light output element 4 includes at least a plurality of first frequency doubling crystals 41 and a plurality of second frequency doubling crystals 42; the lengths of the plurality of first frequency doubling crystals 41 are different from each other, and can be respectively switched to the light path emerging from the laser energy enhancement element 3; the lengths of the plurality of second frequency doubling crystals 42 are different from each other, and can be respectively switched to the light path emerging from the first frequency doubling crystal 41; based on the settings of the plurality of first frequency doubling crystals 41 and the plurality of second frequency doubling crystals 42, different combinations are formed, that is, the combination method of the first frequency doubling crystals 41 and the second frequency doubling crystals 42 with different lengths. Since the conversion efficiency is different when the lengths of the frequency doubling crystals are different, multi-wavelength mixed light with different wavelength ratios can be obtained based on this.

[0051] In some preferred embodiments, the first frequency doubling crystal 41 is a second harmonic generation crystal and can perform type-I or type-II critical phase matching or non-critical phase matching.

[0052] Preferably, the first frequency doubling crystal 41 is a potassium titanyl phosphate (KTP) crystal, a lithium triborate (LBO) crystal, or a barium metaborate (BBO) crystal, with dimensions of 4 mm × 4 mm × 15 mm or 4 mm × 4 mm × 20 mm, and both sides are coated with antireflection films for the fundamental light and the second harmonic light.

[0053] In some preferred embodiments, the second frequency doubling crystal 42 is a fourth harmonic generation crystal and can perform type-I critical phase matching; or, the second frequency doubling crystal 42 is a third harmonic generation crystal and can perform type-II critical phase matching; at this time, when the fundamental light wavelength is near-infrared spectral lines such as 1030 nm, 1047 nm, 1053 nm, 1342 nm, 1338 nm, 1319 nm, 1064 nm, 1079 nm, etc.; the second harmonic light is spectral lines such as 515 nm, 523 nm, 527 nm, 671 nm, 669 nm, 659.5 mm, 532 nm, 539 nm, etc.; the fourth harmonic light is ultraviolet spectral lines such as 257.5 nm, 261.7 nm, 263.2 nm, 335.5 nm, 334.5 nm, 330 nm, 359, 266 nm, 279.7 nm, etc.

[0054] Preferably, the second frequency doubling crystal 42 is a fourth harmonic generation crystal and is a lithium triborate (LBO) crystal, a barium metaborate (BBO) crystal, or a cesium lithium hexaborate (CLBO) crystal; with dimensions of 4 mm × 4 mm × 10 mm or 4 mm × 4 mm × 15 mm, or other dimensions determined according to specific requirements; both sides are coated with antireflection films for the fundamental light, the second harmonic light, and the fourth harmonic light.

[0055] In some preferred embodiments, the second frequency doubling crystal 42 is a third harmonic generation crystal and is a lithium triborate (LBO) crystal; with dimensions of 4 mm × 4 mm × 10 mm or 4 mm × 4 mm × 15 mm, or other dimensions determined according to specific requirements; both sides are coated with antireflection films for the fundamental light, the second harmonic light, and the third harmonic light; at this time, when the fundamental light wavelength is near-infrared spectral lines such as 1030 nm, 1047 nm, 1053 nm, 1342 nm, 1338 nm, 1319 nm, 1064 nm, 1079 nm, etc., the second harmonic light is spectral lines such as 515 nm, 523 nm, 527 nm, 671 nm, 669 nm, 659.5 mm, 532 nm, 539 nm, etc.; the third harmonic light is spectral lines such as 343 n, 349 nm, 351 nmnm, 447 nm, 446 nm, 439.7 nm, 355 nm, 359.7 nm, etc.

[0056] In some preferred embodiments, the first frequency doubling crystal 41 and the second frequency doubling crystal 42 are arranged close to the light output side of the laser energy enhancement element 3; based on this, without a focusing system, high-conversion-efficiency second harmonic generation laser and fourth or third harmonic generation laser outputs can be achieved; specifically, the distances between the first frequency doubling crystal 41 and the second frequency doubling crystal 42 and the light output side of the laser energy enhancement element 3 can be determined according to the size of the output light spot required.

[0057] The embodiments of the present invention have been described above in conjunction with the accompanying drawings. However, the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative rather than restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make many forms without departing from the spirit and scope protected by the present invention and the claims, and all of them fall within the protection scope of the present invention.

Claims

1. A high-energy laser for liquid crystal repair, characterized in that: It includes a semiconductor laser, a beam shaping element, a laser energy enhancement element and a multi-frequency light output element which are sequentially arranged along the light propagation direction; The semiconductor laser is used to emit semiconductor laser; The beam shaping element is used to adjust the energy distribution of the semiconductor laser beam to a flat-top distribution; The laser energy enhancement element is used to enhance the energy of the semiconductor laser and output fundamental frequency light; The multi-frequency light output element is used to perform frequency conversion on the base frequency light to output mixed light containing multiple wavelengths and adjust the proportion of each wavelength of light.

2. The high energy laser for liquid crystal repair according to claim 1, characterized in that: The beam shaping element includes a collimator and a focusing lens; The collimating lens and the focusing lens are arranged in sequence along the light propagation direction, and both are aspherical lenses.

3. The high energy laser for liquid crystal repair according to claim 2, characterized in that: The focal length ratio of the collimating lens and the focusing lens is 1:5-1:

10.

4. The high-energy laser for liquid crystal repair according to claim 1, characterized in that: The laser energy enhancement element includes a Q-switching element and a laser crystal; The Q-switching element is used to enhance the energy of the semiconductor laser to generate giant pulse laser output; The laser crystal is used to convert the high-energy semiconductor laser output by the Q-switching element into fundamental frequency light.

5. The high energy laser for liquid crystal repair according to claim 4, characterized in that: The laser energy enhancement element also includes a first reflector, an output mirror and a total reflector; The first reflector is used to transmit the semiconductor laser into the Q-switching element; The total reflection mirror is used to reflect the high-energy semiconductor laser output by the Q-switching element into the Q-switching element, and then enter the laser crystal after being reflected by the first reflection mirror again; The output mirror is arranged on the light output side of the laser crystal, and is used for reflecting a part of the fundamental frequency light output by the laser crystal and transmitting the other part to the outside.

6. The high-energy laser for liquid crystal repair according to claim 5, characterized in that: The laser energy enhancement element also includes a polarization element and a 1 / 4 wave plate; The polarization element and the quarter wave plate are sequentially arranged on an optical path between the first reflector and the Q-switching element; The polarization element is used to convert the fundamental frequency light into horizontally polarized linear polarized light, and reflect the fundamental frequency light reflected by the total reflection mirror to the outside; The 1 / 4 wave plate is used to rotate the polarization direction of the fundamental frequency light by 45°; The Q-switching element is also used to rotate the polarization direction of the fundamental frequency light.

7. The high energy laser for liquid crystal repair according to claim 6, characterized in that: The polarization element is a fundamental frequency light polarizer, which is arranged at a fundamental frequency light Brewster angle in the horizontal direction with the optical axis and is coated with an anti-reflection film in the horizontal direction and a high-reflection film in the vertical direction.

8. The high-energy laser for liquid crystal repair according to claim 5, characterized in that: The first reflector is a plane mirror, which is arranged at an angle of 45° with the optical axis. Both sides are coated with semiconductor laser anti-reflection films, and the side close to the laser crystal is also coated with a fundamental frequency light high-reflection film.

9. The high-energy laser for liquid crystal repair according to claim 5, characterized in that: The total reflection mirror is a plano-concave mirror, with the concave surface facing the Q-switching element, and the curvature radius of the total reflection mirror is 500-1000 mm.

10. The high energy laser for liquid crystal repair according to claim 5, characterized in that: The output mirror is a plane mirror, one side of which is coated with a fundamental frequency light partial reflection film facing the laser crystal, and the other side of which is coated with a fundamental frequency light anti-reflection film.

11. The high energy laser for liquid crystal repair according to claim 1, characterized in that: The multi-frequency light output element comprises at least a plurality of first frequency doubling crystals and a plurality of second frequency doubling crystals; The first frequency doubling crystals have different lengths and can be switched to the output light path of the laser energy enhancement element respectively; The plurality of second frequency doubling crystals have different lengths and can be respectively switched to the output light path of the first frequency doubling crystal.

12. The high energy laser for liquid crystal repair according to claim 11, characterized in that: The first frequency doubling crystal is a frequency doubling crystal and is capable of performing type I or type II critical phase matching or non-critical phase matching.

13. The high energy laser for liquid crystal repair according to claim 12, characterized in that: The second frequency doubling crystal is a quadruple frequency doubling crystal and is capable of performing type I critical phase matching; or, The second frequency doubling crystal is a frequency tripling crystal and is capable of performing type II critical phase matching.

14. The high energy laser for liquid crystal repair according to claim 11, characterized in that: The first frequency doubling crystal and the second frequency doubling crystal are arranged close to the light emitting side of the laser energy enhancement element.

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