A single wavelength angularly pumped athermalized, thermally insensitive laser

Abstract

The present invention relates to a single wavelength angle pumped athermal and heat insensitive laser, which comprises a lens fixing group, an optical rotation group, a polarizing group, an electro-optical Q-switching group, an optical path adjustment group, a folding angle cone group, a bonding crystal group, an angle side pump module group, and a heat dissipation group. Two lens fixing groups are arranged side by side at one end of the laser, and the folding angle cone group is arranged at the other end of the laser. The upper lens fixing group and the optical rotation group, the polarizing group, the electro-optical Q-switching group, and the optical path adjustment group are fixed on the upper part of the laser in sequence, and the lower lens fixing group and the bonding crystal group are fixed on the lower part of the laser in sequence. The angle side pump module group and the heat dissipation group are both fixed around the bonding crystal group. When the angle side pump module group emits light, the light passes through the bonding crystal group and is reflected by the folding angle cone group, and then passes through the optical path adjustment group, the electro-optical Q-switching group, the polarizing group, and the optical rotation group in sequence, and finally emits from the upper lens fixing group.

Description

Technical Field

[0001] The invention relates to the technical field of solid lasers, and in particular to a single-wavelength angularly pumped athermalized and heat-insensitive laser. Background Art

[0002] Solid-state lasers are widely used in the fields of laser ranging, laser irradiation, laser imaging, etc., and their development direction is temperature-free, low power consumption, miniaturization and high stability. Existing solid-state lasers on the market generally require about 3 minutes of preparation time to work normally under high and low temperature test environments, which is difficult to meet the use requirements. In addition, due to the existence of temperature control circuits, the power consumption of related products is high, and the battery life is insufficient, making it difficult to ensure the sustainable combat capability of the equipment.

[0003] Our company has previously developed a series of different types of solid-state lasers, such as CN202695966U, CN107768968A, CN110911954A, CN111342331A, etc. On this basis, we have developed a new type of single-wavelength angle-pumped athermalized and heat-insensitive laser. Summary of the invention

[0004] One of the purposes of the present invention is to provide a single wavelength angle pumped athermal and heat insensitive laser, the laser comprising a lens fixing group (1), an optical rotation group (2), a polarizing group (3), an electro-optical Q-switching group (4), an optical path adjustment group (5), a folding angle cone group (6), a bonding crystal group (7), an angle side pump module group (8), and a heat dissipation group (9); wherein the number of the lens fixing groups (1) is two, which are arranged side by side in an upper and lower row at one end of the laser, and the folding angle cone group (6) is arranged at the other end of the laser; the upper lens fixing group (1) and the optical rotation group (2), the polarizing group (3), the electro-optical Q-switching group (4), and the optical path adjustment group (5) are sequentially connected to each other to form a laser beam. The optical path is fixed on the upper part of the laser, and the lower row of lens fixing groups (1) and the bonded crystal group (7) are fixed on the lower part of the laser together with the optical path; the corner side pump module group (8) and the heat dissipation group (9) are both fixed around the bonded crystal group (7); after the corner side pump module group (8) emits light, the light directly enters the bonded crystal group (7) or enters the bonded crystal group (7) after being reflected by the lower row of lens fixing groups (1); the light emitted from the bonded crystal group (7) is reflected by the folding angle cone group (6), and then passes through the optical path adjustment group (5), the electro-optical Q-switching group (4), the polarizing group (3), and the optical rotation group (2) in sequence, and finally is emitted from the upper row of lens fixing groups (1).

[0005] Furthermore, the lens fixing group (1) comprises an output mirror (1-1) or a reflective mirror (1-2), a lens pressing ring (1-3), a lens fixing frame (1-4), and a sealing spacer (1-5), wherein the output mirror (1-1) or the reflective mirror (1-2) is fixed in a mounting hole of the lens fixing frame (1-4) and is pressed by the lens pressing ring (1-3), and the lens fixing frame (1-4) and the sealing spacer (1-5) are fixedly connected to achieve sealing.

[0006] Furthermore, the output mirror (1-1) is a convex Gaussian output mirror, and the reflecting mirror (1-2) is a concave mirror.

[0007] Furthermore, the optical rotation group (2) comprises a mounting seat (2-1), a wave plate (2-2), and a pressure ring (2-3), wherein the wave plate (2-2) is fixed in a mounting hole of the mounting seat (2-1) and is pressed by the pressure ring (2-3). The optical rotation group is mainly used to improve the depolarization effect of the corner cone and increase the laser energy output.

[0008] Furthermore, the wave plate (2-2) is specifically a 1 / 4λ vacuum zero-order wave plate.

[0009] Furthermore, the polarizing group (3) comprises a polarizing mounting seat (3-1) and a polarizer (3-2), wherein the polarizer (3-2) is glued to the polarizing mounting seat (3-1). The polarizer is mainly used to control the polarization state of the laser to be linearly polarized light, providing a guarantee for the electro-optical Q-switching operation.

[0010] Furthermore, the polarizer (3-2) is a polarization beam splitter prism, and the parallelism difference between the two light passing surfaces is 10".

[0011] Furthermore, the electro-optical Q-switching group (4) comprises a Q-switching mounting insulating seat (4-1), an electro-optical Q-switching crystal (4-2), and a fixing seat (4-3), wherein the electro-optical Q-switching crystal (4-2) is fixed on the Q-switching mounting insulating seat (4-1), and the fixing seat (4-3) is fixed on the Q-switching mounting insulating seat (4-1). The electro-optical Q-switching group is mainly used in conjunction with an external drive to control the switch of the laser output to achieve pulse output.

[0012] Furthermore, the electro-optical Q-switched crystal (4-2) is a KTP crystal, which is a specially customized crystal with more stable high and low temperature performance.

[0013] Furthermore, the optical path adjustment group (5) comprises an optical wedge mounting seat (5-1), an optical wedge (5-2), an optical wedge seat (5-3), and an optical wedge pressing ring (5-4), wherein the optical wedge (5-2) is glued into the optical wedge mounting seat (5-1) and is pressed by the optical wedge pressing ring (5-4), and the optical wedge mounting seat (5-1) is fixed on the optical wedge seat (5-3).

[0014] Furthermore, the optical wedge (5-2) is a 15' optical wedge.

[0015] Furthermore, the folding angle cone group (6) comprises a corner cone prism (6-1), a rubber pad (6-2), and a pressure plate (6-3), wherein the corner cone prism (6-1) is fixed in a fixing groove at the end of the laser and is pressed by the rubber pad (6-2), and the pressure plate (6-3) is connected to the fixing groove and locked. The folding angle cone group is mainly used to realize the folding of the laser light path and increase the laser resonance cavity length within a limited length.

[0016] Furthermore, the corner cube prism (6-1) is specifically a cube corner prism. The prism has a self-collimation property, that is, the incident light and the outgoing light are always parallel, thereby ensuring the consistency of the resonant light path.

[0017] Furthermore, the bonded crystal group (7) comprises a Nd:YAG bonded crystal (7-1), a crystal heat sink (7-2), a crystal press block I (7-3), and a crystal press block II (7-4), wherein the Nd:YAG bonded crystal (7-1) is bonded to the crystal heat sink (7-2) using thermally conductive silicone rubber, and the crystal press block I (7-3) and the crystal press block II (7-4) are respectively fixed at two ends of the Nd:YAG bonded crystal (7-1).

[0018] Furthermore, the corner side pump module group (8) comprises a heat sink (8-1), a multi-wavelength corner side pump module (8-2), and a temperature sensor, wherein the multi-wavelength corner side pump module (8-2) is fixedly connected to the heat sink (8-1), and the temperature sensor is fixed in the heat sink (8-1). The temperature sensor is used to monitor the temperature of the multi-wavelength corner side pump module in real time and feed it back to the control circuit to protect the multi-wavelength corner side pump module.

[0019] Furthermore, the number of the corner side pump module groups (8) is 2 groups, both of which are tilted at a certain angle to face the bonded crystal group (7), and their wavelength distribution is 792.2nm, 811.8nm and 823nm.

[0020] Furthermore, the heat dissipation group (9) comprises at least one of a heat sink (9-1) and a fan. The heat dissipation group is mainly used for heat dissipation of the corner side pump module group.

[0021] Compared with existing similar products, the single-wavelength angle-pumped athermal and heat-insensitive laser provided by the present invention has the advantages of no temperature control, low power consumption, miniaturization, compactness, stability and sustainable operation. It can work immediately after being turned on without temperature control in the temperature range of -45°C to 65°C, and can output 1064nm single-wavelength laser with laser energy of not less than 80mJ. In addition, the resonant cavity structure of the laser is easy to debug, and the Gaussian mirror is combined with the angle cone to form a laser resonant cavity, which has good anti-disturbance stability, and the laser output beam divergence angle is small, avoiding film damage to the optical elements in the cavity, and taking into account the purpose of stability and miniaturization while no temperature control and low power consumption.

[0022] The present invention also fully considers the output wavelength drift of the multi-wavelength angle side pump module under environmental testing, the amplification and loss of the one-way gain, the length of the laser medium and the absorption heat effect of the doping concentration on the laser output energy and stability, and optimizes the combination to ensure low heat dissipation, high absorption efficiency, and stable thermal balance. Under the condition of ensuring reliable output without temperature control and low power consumption of the laser, single wavelength laser output, small volume and weight, and stable performance are achieved. All structural components of the entire laser are ordinary metal parts or plastic parts, and no special processing technology is required in manufacturing, which not only reduces the production cost but also improves the production efficiency, and can meet the requirements of military lasers that can work immediately after starting without temperature control, low power consumption, miniaturization, and sustainable operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a cross-sectional view of the overall structure of the laser of the present invention;

[0024] Figure 2 is a cross-sectional view of the lens fixing assembly of the present invention;

[0025] Figure 3 is a cross-sectional view of the optical rotation group of the present invention;

[0026] Figure 4 is a cross-sectional view of a polarizing group of the present invention;

[0027] Figure 5 It is a left view of the electro-optical Q-switching group of the present invention;

[0028] Figure 6 is a cross-sectional view of the optical path adjustment group of the present invention;

[0029] Figure 7 A cross-sectional view of a folded corner pyramid assembly according to the present invention;

[0030] Figure 8 A top view of a bonded crystal group of the present invention;

[0031] Fig. 9 It is a front view of the corner side pump module assembly of the present invention;

[0032] Fig.10 It is a front view of the heat dissipation group of the present invention. DETAILED DESCRIPTION

[0033] In order to enable ordinary technicians in the field to fully understand the technical solutions and beneficial effects of the present invention, further description is given below in conjunction with specific embodiments and drawings.

[0034] like Figure 1 The single-wavelength angularly pumped athermal and thermally insensitive laser shown mainly comprises, from right to left and from top to bottom, a lens fixing group 1, an optical rotation group 2, a polarizing group 3, an electro-optical Q-switching group 4, an optical path adjustment group 5, a folded angle cone group 6, a bonding crystal group 7, an angle side pump module group 8, a heat dissipation group 9, a cover plate 10 for sealing the laser opening, and a lens fixing group 1, which are introduced one by one in conjunction with the corresponding schematic diagrams below.

[0035] like Figure 2 As shown, there are two groups of lens fixing groups 1, which are arranged side by side. The structures of the two groups are similar, including output mirror 1-1 or reflector 1-2, lens pressing ring 1-3, lens fixing frame 1-4, and sealing spacer 1-5. The output mirror 1-1 and the reflector 1-2 are respectively installed in different lens fixing frames 1-4, the lens pressing ring 1-3 is installed on the output mirror 1-1 or the reflector 1-2 and presses it, and the sealing spacer 1-5 is installed in the lens fixing frame 1-4. The output mirror 1-1 uses a convex Gaussian output mirror, which is mainly used for laser output; the reflector 1-2 uses a concave mirror, which is mainly used to achieve total reflection of the light path; the sealing spacer 1-5 is mainly used for dust prevention, and the lens pressing ring 1-3 is mainly used to fasten the lens. The overall cavity type of the laser is a concave-convex unstable cavity structure. The coating of all optical components in the cavity is a 1.064μm anti-reflection film, and the transmittance is greater than 99.8%. The total reflective mirror has a reflectivity of 99.8% to 1.064μm.

[0036] like Figure 3 As shown, the optical rotation group 2 mainly includes a mounting seat 2-1, a wave plate 2-2 (1 / 4λ vacuum zero-order wave plate) and a pressure ring 2-3. The wave plate 2-2 is installed in the mounting hole of the mounting seat 2-1, and the pressure ring 2-3 is installed in the mounting seat 2-1 and presses the wave plate. An arc groove for rotating the wave plate is opened on the mounting seat 2-1. When in use, the wave plate 2-2 is rotated through the arc groove according to actual conditions to ensure that the pressure ring 2-3 is tightened when the laser energy is maximum.

[0037] like Figure 4 As shown, the polarizing group 3 includes a polarizing mount 3-1 and a polarizer 3-2. The material of the polarizing mount 3-1 is 4J45, and the polarizer 3-2 is glued to the polarizing mount 3-1 to control the polarization state of the laser to be linearly polarized light, thereby providing a guarantee for the electro-optical Q-switching operation. The polarizer 3-2 uses a polarization beam splitter prism, and the parallel difference between the two light passing surfaces is 10".

[0038] like Figure 5 As shown, the electro-optical Q-switching group 4 includes a Q-switching mounting insulating seat 4-1, an electro-optical Q-switching crystal 4-2 (KTP crystal) and a fixing seat 4-3. The electro-optical Q-switching crystal 4-2 is mounted on the Q-switching mounting insulating seat 4-1, and the fixing seat 4-3 is mounted on the Q-switching mounting insulating seat 4-1.

[0039] like Figure 6 As shown, the optical path adjustment group 5 includes an optical wedge mounting seat 5-1, an optical wedge 5-2 (15' optical wedge), an optical wedge seat 5-3 and an optical wedge pressing ring 5-4. An arc groove is formed on the optical wedge seat 5-3, and the optical wedge 5-2 is glued into the optical wedge mounting seat 5-1 and its relative position is adjusted by the arc groove. The optical wedge mounting seat 5-1 is installed in the optical wedge seat 5-3 and fastened by screws, and the optical wedge pressing ring 5-4 is installed in the optical wedge seat 5-3. The laser resonance is corrected by rotating the optical wedge 5-2.

[0040] like Figure 7 As shown, the optical path deflection group 6 includes a corner cube prism 6-1, a rubber pad 6-2 and a pressure plate 6-3. The corner cube prism 6-1 is installed in the fixing groove at the end of the laser, the rubber pad 6-2 is installed in the depression of the pressure plate 6-3, and the pressure plate 6-3 is installed on the fixing groove and fastened by screws.

[0041] like Figure 8 As shown, the bonded crystal group 7 includes a Nd:YAG bonded crystal 7-1, a crystal heat sink 7-2, a crystal pressing block I 7-3, and a crystal pressing block II 7-4. The Nd:YAG bonded crystal 7-1 is bonded to the crystal heat sink 7-2 by means of thermally conductive silicone rubber, and the crystal pressing block I 7-3 and the crystal pressing block II 7-4 are both mounted on the surface of the Nd:YAG bonded crystal 7-1 and fastened by screws. The bonded crystal is specifically a 1% doped Nd:YAG slab with a length of 65 mm, which is prepared by a diffusion glueless bonding method. By bonding a spontaneous radiation light absorbing (not absorbing pump light) material structure around the side of the composite crystal gain medium, the parasitic oscillation loop is cut off, the high-density inversion particle energy storage causes ASE and parasitic oscillation consumes energy storage during the Q-switching process, the optical-to-optical conversion efficiency of the laser is improved, the volume and weight of the equipment are reduced, the power consumption of the battery is reduced, and compactness and lightness are achieved.

[0042] like Fig. 9As shown, the corner side pump module group 8 includes a heat sink 8-1, a multi-wavelength corner side pump module 8-2 and a temperature sensor. The multi-wavelength corner side pump module 8-2 is installed on the heat sink 8-1 and fastened by screws, and the temperature sensor is installed in the heat sink 8-1. The wavelength distribution of the multi-wavelength corner side pump module 8-2 is 792.2nm, 811.8nm and 823nm. By bonding undoped YAG outside the gain medium crystal with an absorption layer, the pump light is confined inside the gain medium. The pump light will be reflected back after multiple reflections, and the absorption length will increase, so that the gain medium can fully absorb the pump light when the absorption coefficient is the minimum, ensuring that the pump absorption efficiency remains basically unchanged when the pump light wavelength changes over a wide temperature range.

[0043] like Fig.10 As shown, the heat dissipation group 9 includes a heat sink 9-1, a fan mounting seat 9-2 and a fan. The fan is mounted in the fan mounting seat 9-2, and the fan mounting seat 9-2 is mounted on the heat sink 9-1. The heat dissipation group mainly functions to force cooling and heat dissipation of the diagonal pump module group.

[0044] When the laser power supply is powered on, the corner pump module 8 emits light, and oscillates in the resonant cavity through the Nd:YAG bonded crystal 7-1, the corner cone prism 6-1, the optical path adjustment group 5-2, the electro-optical Q-switched crystal 4-2, the polarizer 3-2, the reflector 1-2 and the output mirror 1-1 in sequence; after the laser stabilizes the oscillation, it is emitted from the output mirror 1-1 to achieve pulsed laser output. The laser provided by the present invention can work immediately after being turned on without temperature control within the temperature range of -45°C to 65°C, and outputs a single wavelength of 1064nm, with a laser energy of not less than 80mJ, low power consumption, simple and convenient debugging, small laser output beam divergence, and high output laser stability.

Claims

1. A single wavelength angularly pumped athermalized, thermally insensitive laser, characterized by: The laser comprises a lens fixing group (1), an optical rotation group (2), a polarizing group (3), an electro-optical Q-switching group (4), an optical path adjustment group (5), a folded angle cone group (6), a bonded crystal group (7), an angle side pump module group (8), and a heat dissipation group (9). The polarizing group (3) comprises a polarizer (3-2), wherein the polarizer (3-2) is a polarization beam splitter prism; the angle side pump module group (8) comprises a heat sink (8-1), a multi-wavelength angle side pump module (8-2), and a temperature sensor, wherein the multi-wavelength angle side pump module (8-2) is fixedly connected to the heat sink (8-1), and the temperature sensor is fixed in the heat sink (8-1); the number of the angle side pump module groups (8) is 2, and the two are tilted at a certain angle to face the bonded crystal group (7); the number of the lens fixing groups (1) is 2, and they are arranged side by side up and down at one end of the laser. The folding angle cone group (6) is arranged at the other end of the laser; the upper lens fixing group (1) and the optical rotation group (2), the polarizing group (3), the electro-optical Q-switching group (4), and the optical path adjustment group (5) are fixed on the upper part of the laser in the same optical path, and the lower lens fixing group (1) and the bonding crystal group (7) are fixed on the lower part of the laser in the same optical path; the corner side pump module group (8) and the heat dissipation group (9) are fixed around the bonding crystal group (7); after the corner side pump module group (8) emits light, the light directly enters the bonding crystal group (7) or enters the bonding crystal group (7) after being reflected by the lower lens fixing group (1); the light emitted from the bonding crystal group (7) is reflected by the folding angle cone group (6), passes through the optical path adjustment group (5), the electro-optical Q-switching group (4), the polarizing group (3), and the optical rotation group (2) in sequence, and finally emits from the upper lens fixing group (1).

2. The laser according to claim 1, characterized in that: The lens fixing group (1) comprises an output mirror (1-1) and a reflector (1-2), wherein the output mirror (1-1) is a convex Gaussian output mirror, and the reflector (1-2) is a concave mirror.

3. The laser according to claim 1, characterized in that: The optical rotation group (2) comprises a wave plate (2-2), wherein the wave plate (2-2) is specifically a 1 / 4λ vacuum zero-order wave plate.

4. The laser according to claim 1, characterized in that: The parallelism difference between the two light surfaces of the polarizing beam splitter is 10".

5. The laser according to claim 1, characterized in that: The electro-optical Q-switching group (4) comprises an electro-optical Q-switching crystal (4-2), wherein the electro-optical Q-switching crystal (4-2) is a KTP crystal.

6. The laser according to claim 1, characterized in that: The optical path adjustment group (5) comprises an optical wedge (5-2), wherein the optical wedge (5-2) is specifically a 15′ optical wedge.

7. The laser according to claim 1, characterized in that: The folded corner cone group (6) comprises a corner cone prism (6-1), wherein the corner cone prism (6-1) is specifically a cube corner prism.

8. The laser according to claim 1, characterized in that: The bonded crystal group (7) includes a Nd:YAG bonded crystal (7-1).

9. The laser according to claim 1, characterized in that: The wavelength distribution of the corner side pump module group (8) is 792.2nm, 811.8nm and 823nm.

10. The laser according to claim 1, characterized in that: The heat dissipation group (9) comprises at least one of a heat sink (9-1) and a fan.

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