Bilateral pump erbium glass laser

Abstract

The utility model relates to a kind of double-sided pump erbium glass laser, belong to laser technology field.The utility model proposes a kind of double-sided pump erbium glass laser, using double Bar strip side face dislocation pumping and FC-770 fluorination liquid total immersion cooling method, realizes erbium glass laser high-power pumping and high-efficiency heat dissipation, both can effectively improve erbium glass laser single pulse energy and beam quality, also can substantially reduce laser complete machine volume.

Description

Technical Field

[0001] This utility model belongs to the field of laser technology, specifically relating to a double-sided pumped erbium glass laser. Background Technology

[0002] The 1.5μm wavelength is in a band where the human eye is not sensitive, and the allowable exposure for the human eye is 400,000 times that of the 1064nm Nd:YAG laser and 100 times that of the 10.6μm CO2 laser. Secondly, the 1.5μm laser is located in the third atmospheric transmission window, and has strong penetrating ability through smoke and fog. Therefore, the 1.5μm wavelength laser has been widely used in laser ranging, atmospheric detection, lidar, optical communication, and cosmetic surgery.

[0003] Currently, there are three technical methods for outputting 1.5μm wavelength eye-safe lasers: Optical Parametric Oscillator (OPO), Stimulated Raman Scattering (SRS), and direct output. OPO and SRS typically obtain 1.06μm lasers by frequency conversion, resulting in complex system structures, which are unsuitable for military applications such as individual soldier combat, and are also relatively expensive. Direct output of 1.5μm lasers is the most ideal method for achieving mass production, miniaturization, and widespread application. Direct output of 1.5μm lasers includes two methods: one is through direct production of semiconductor laser diodes, and the other is through diode-pumped erbium glass. Laser diodes have poor beam quality, and semiconductor materials are easily affected by temperature, resulting in low stability. Because erbium-ytterbium co-doped phosphate glass has a long upper-level lifetime, high erbium-ytterbium energy transfer efficiency, and is less prone to fluorescence quenching, and because its production conditions are mature, it is currently the most commonly used gain medium for low-repetition-rate direct output of 1.5μm eye-safe lasers. For erbium glass lasers with millijoule or hundred-millijoule output, side pumping is typically used. Utility Model Content

[0004] (a) Technical problems to be solved

[0005] The technical problem to be solved by this utility model is to propose a double-sided pumped erbium glass laser to solve the problems of residual light damage to the pump source caused by high-power double-sided pumping and thermal effects caused by uneven heat dissipation.

[0006] (II) Technical Solution

[0007] To solve the above-mentioned technical problems, this utility model provides a double-sided pumped erbium glass laser, including erbium glass 1, a fast-axis collimating lens 1 2, a fast-axis collimating lens 2 3, a first set of bar strips 4, a second set of bar strips 5, a heat sink 6, a Q-switching crystal 7, an output mirror 8, a total reflection mirror 9, and a laser housing 10; the erbium glass 1 is bonded to the heat sink 6, the fast-axis collimating lens 1 2 is bonded to the first set of bar strips 4, and the fast-axis collimating lens 2 3 is bonded to the second set of bar strips 5; the fast-axis collimating lens 2... 3. The second set of Bar strips 5 is located on one side of the erbium glass 1, and the fast axis collimating lens 2 and the first set of Bar strips 4 are located on the other side of the erbium glass 1, with the first set of Bar strips 4 and the second set of Bar strips 5 arranged in a staggered manner; the heat sink 6 is fastened to the laser housing 10 by screws; the Q-switching crystal 7 is bonded to the position between the heat sink 6 and the output mirror 8 inside the laser housing 10; the output mirror 8 and the total reflection mirror 9 are fixed in the corresponding mounting holes on the laser housing 10, and the output mirror 8 and the total reflection mirror 9 form a resonant cavity.

[0008] Preferably, the pump light emitted from the first set of Bars 4 is collimated by the fast-axis collimating lens 2 and then enters the erbium glass 1 for pumping, and the second set of Bars 5 is collimated by the fast-axis collimating lens 3 and then enters the erbium glass 1 for pumping.

[0009] Preferably, the heat sink 6 is capable of dissipating heat from the erbium glass 1 and the two sets of bar strips.

[0010] Preferably, the Q-switched crystal 7 is capable of laser pulse modulation.

[0011] Preferably, the erbium glass 1, the two sets of bar strips, the two fast-axis collimating lenses, and the Q-switched crystal 7 are all immersed in the coolant.

[0012] Preferably, the coolant is FC-770 fluorinated liquid.

[0013] Preferably, the erbium glass 1 is Erbium 3+ / Yb 3+ Phosphate-doped glass.

[0014] Preferably, the center wavelength of both sets of Bar strips is 976nm.

[0015] Preferably, the Q-switching crystal 7 is Co. 2+ :MgAl2O4.

[0016] Preferably, the output mirror 8 and the total reflection mirror 9 are fastened to the laser housing (10) by a pressure ring.

[0017] (III) Beneficial Effects

[0018] This invention proposes a dual-sided pumped erbium glass laser, which employs a dual-bar side-displacement pumping method and a full immersion cooling method with FC-770 fluoride liquid. This achieves high-power pumping and efficient heat dissipation of the erbium glass laser, effectively improving the single-pulse energy and beam quality of the erbium glass laser while significantly reducing the overall size of the laser. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the double-pumped erbium glass laser structure of this utility model;

[0020] Figure 2 This is a planar layout diagram of the double-pumped erbium glass laser of this utility model. Detailed Implementation

[0021] To make the objectives, contents, and advantages of this utility model clearer, the specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples.

[0022] For erbium-glass lasers with millijoule or hundred-millijoule output, a dual-pumping method is typically used. However, with the increase of pump power, there is a risk that residual pump light will enter the opposing pump source and damage the bar. In addition, erbium-glass lasers with millijoule or hundred-millijoule output currently use an external circulating water tank and conduct heat dissipation through a copper heat sink. This cooling method can play a role in heat dissipation to some extent, but it generally involves one large surface of the slab crystal in close contact with the heat sink for conduction heat dissipation, while the other large surface is an insulating surface. Therefore, there is a very large temperature gradient in the thickness direction, which can easily cause wavefront distortion, thermal birefringence, and thermal lensing effects, seriously affecting the high beam quality laser output. At the same time, it also results in a large laser size, making it very inconvenient to carry and use.

[0023] Therefore, this embodiment proposes a dual-sided pumped erbium glass laser, such as... Figure 1 As shown, it includes erbium glass 1, fast-axis collimating lens 1 2, fast-axis collimating lens 2 3, first group of bar bars 4, second group of bar bars 5, heat sink 6, passive Q-switched crystal 7, output mirror 8, total reflection mirror 9, and laser housing 10.

[0024] Among them, erbium glass 1 is Er 3+ / Yb 3+ Phosphate-doped glass, with both sets of Bar bars having a center wavelength of 976 nm. The passively Q-switched crystal 7 is Co. 2+ :MgAl2O4.

[0025] Erbium glass 1 is bonded to heat sink 6, fast-axis collimating lens 1 2 is bonded to the first set of bar strips 4, and fast-axis collimating lens 2 3 is bonded to the second set of bar strips 5; fast-axis collimating lens 2 3 and the second set of bar strips 5 are located on one side of erbium glass 1, and fast-axis collimating lens 1 2 and the first set of bar strips 4 are located on the other side of erbium glass 1; heat sink 6 is fastened to laser housing 10 by screws; Q-switching crystal 7 is bonded to the position between heat sink 6 and output mirror 8 inside laser housing 10; output mirror 8 and total reflection mirror 9 are fastened to the corresponding mounting holes on laser housing 10 by clamping rings.

[0026] The first set of Bars 4 and the second set of Bars 5 are arranged in a staggered manner. The pump light emitted from the first set of Bars 4 is collimated by the fast-axis collimating lens 2 and then enters the erbium glass 1 for pumping. The high-energy particle beam continuously increases, thereby generating stimulated emission. The second set of Bars 5 is collimated by the fast-axis collimating lens 3 and then enters the erbium glass 1 for pumping. The high-energy particle beam continuously increases, thereby generating stimulated emission. In this way, good mode matching can be formed, and the unabsorbed residual pump light can be prevented from entering the opposite set of Bars.

[0027] Initially, the Q-switched crystal 7 has a large absorption coefficient and low light transmittance, resulting in a low Q value (high loss) state within the cavity, preventing oscillation. As the optical pumping effect occurs, the inverted particle beam accumulates continuously, causing the Q-switched crystal 7 to absorb light intensity to saturate and suddenly become "bleached." At this point, the Q value within the cavity surges, oscillation occurs, and a laser pulse is generated and output from the output mirror 8.

[0028] The heat sink 6 can dissipate heat for the erbium glass 1 and the two sets of bar strips, the Q-switched crystal 7 can realize laser pulse modulation, and the output mirror 8 and the total reflection mirror 9 form a resonant cavity.

[0029] To reduce the thermal effect, a full liquid cooling method is adopted, in which the erbium glass 1, the two sets of Bar strips, the two fast-axis collimating lenses, and the Q-switching crystal 7 are all immersed in FC-770 fluorinated liquid for direct cooling, which can quickly remove waste heat to ensure output energy and beam quality.

[0030] The coolant used is 3M's FC-770 fluorinated liquid, which boasts advantages such as good insulation, high thermal conductivity, a high boiling point of 95℃, a low freezing point of -127℃, low volatility, and a low refractive index of 1.27. The two fast-axis collimating lenses, erbium glass 1, and Q-switched crystal 7 are directly immersed in it for cooling, without affecting the optical path or the energization of the two sets of bar strips. Furthermore, experimental measurements show that the FC-770 fluorinated liquid has very low absorption coefficients in the 976nm and 1535nm wavelength bands. Therefore, this cooling method reduces the laser's size while also improving the beam quality and single-pulse energy of the erbium glass laser.

[0031] In this invention, the staggered arrangement of the double bars ensures high-power pump light injection while preventing unabsorbed residual pump light from entering the opposite bar. Furthermore, the full immersion cooling method using FC-770 fluoride liquid reduces the thermal effect, achieving effective heat dissipation for the entire laser and reducing beam quality degradation and laser energy reduction caused by thermal effects, while also reducing the laser size.

[0032] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A double-sided pumped erbium glass laser, characterized in that, The system includes erbium glass (1), fast-axis collimating lens one (2), fast-axis collimating lens two (3), first set of bar strips (4), second set of bar strips (5), heat sink (6), Q-switched crystal (7), output mirror (8), total reflection mirror (9), and laser housing (10); the erbium glass (1) is bonded to the heat sink (6), the fast-axis collimating lens one (2) is bonded to the first set of bar strips (4), and the fast-axis collimating lens two (3) is bonded to the second set of bar strips (5); the fast-axis collimating lens two (3) and the second set of bar strips (5) are located on the erbium glass. On one side of the glass (1), the fast-axis collimating lens (2) and the first set of Bar strips (4) are located on the other side of the erbium glass (1), and the first set of Bar strips (4) and the second set of Bar strips (5) are staggered; the heat sink (6) is fastened to the laser housing (10) by screws; the Q-switching crystal (7) is bonded to the position between the heat sink (6) and the output mirror (8) inside the laser housing (10); the output mirror (8) and the total reflection mirror (9) are fixed in the corresponding mounting holes on the laser housing (10), and the output mirror (8) and the total reflection mirror (9) form a resonant cavity.

2. The double-sided pumped erbium glass laser as described in claim 1, characterized in that, The pump light emitted by the first set of Bars (4) is collimated by the fast axis collimating lens 1 (2) and then enters the erbium glass (1) for pumping. The second set of Bars (5) is collimated by the fast axis collimating lens 2 (3) and then enters the erbium glass (1) for pumping.

3. The double-sided pumped erbium glass laser as described in claim 1, characterized in that, The heat sink (6) can dissipate heat from the erbium glass (1) and the two sets of bar strips.

4. The double-sided pumped erbium glass laser as described in claim 1, characterized in that, The Q-switched crystal (7) can achieve laser pulse modulation.

5. The double-sided pumped erbium glass laser as described in claim 1, characterized in that, The erbium glass (1), two sets of bar bars, two fast-axis collimating lenses, and Q-switching crystal (7) are all immersed in coolant.

6. The double-sided pumped erbium glass laser as described in claim 5, characterized in that, The coolant is FC-770 fluorinated liquid.

7. The double-sided pumped erbium glass laser as described in claim 1, characterized in that, The erbium glass (1) is Er 3+ / Yb 3+ Phosphate-doped glass.

8. The double-sided pumped erbium glass laser as described in claim 1, characterized in that, The center wavelength of both sets of bar strips is 976nm.

9. The double-sided pumped erbium glass laser as described in claim 1, characterized in that, The Q-switching crystal (7) is Co 2+ :MgAl2O4.

10. The double-sided pumped erbium glass laser as described in any one of claims 1 to 9, characterized in that, The output mirror (8) and total reflection mirror (9) are fastened to the laser housing (10) by pressure rings.

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