Studies on the Thermal Effect Managements in the Laser-Diode Pumped Solid-State Laser Module

1.在研制激光二极管抽运的高平均功率固体激光驱动模块时，需要补偿激光介质中的热变、热双折射和热变形等热效应，并补偿有源光学元件。本文首先编制了三维热效应分析程序，并通过与实验结果的比较对程序进行了改进。然后利用该代码设计了二极管泵浦固体激光器（DPSSL）驱动模块。设计了一种输出能量最小（10J × 10h_2）的高平均功率核聚变激光器(HALNA)-10型DPSSL驱动模块。射流水冷激光二极管（LD）阵列也可用于泵送未来的HALNA DPSSL。在此基础上，提出了一种考虑热效应的大功率LD阵列评价方法、高平均功率100-W级DPSSL的评价方法，并开发了更多的应用于IFE和工业。对所构建的HALNA-10型DPSSL的输出特性进行了详细的测量，结果与理论计算结果吻合较好。然而，为了实现10hz的工作，必须补偿热透镜效应，以补偿热折射。结果表明，对于平均功率小于10W的DPSSL偏振计，可以使用四分之一波长片来测量激光介质和有源光学元件中的二维热双冷分布。对新开发的三维热效应板规范（THESLAC）进行了改进，该规范解释了实验结果。设计了HALNA-10 ~ 20 DPSSL (10J ~ 20J×10 H_2)，在10hz下可以达到10J ~ 20J的输出能量。利用slac代码，设计了HALNA-10 ~ 20 DPSSL (10J ~ 20J×10 H_2)，在10hz下可以达到10J ~ 20J的输出能量。当100w ~ 1kw的1053 nm激光通过法拉第旋转器玻璃时，实验预期退极化损失超过10%。然而，这种去偏振损失可以通过在法拉第玻璃之间使用67.5度的石英旋转器来补偿。研究表明，当100W级激光在1064 nm处通过时产生的热双折射可以通过使用90度的石英旋转器来补偿。结论HALNA-10 DPSSL所产生的热效应具有可比性。然后，我们有信心下一个HALNA 10 ~ 20 DPSSL将在10 Hz下工作。所开发的slac代码将有助于开发用于工业Less的高平均功率dpssl

1.IntroductionWhen a laser-diode-pumped high-average-power solid-state laser driver module Is deveroped for the laser-tnertial -fusion energy (IFE), thermal effect, such as thermal lerislng, thermal birefringence and thermal deformation, in the laser medium and the active optical elements should be compensated for. In this studies, a 3D thermal-effect analysis code is first developed, and by comparing with experimental results the code is improved. After then by use of the code the diode-pumped solid-state laser (DPSSL) driver module is newly designed2. Design, Development and Evaluation of a DPSSL Driver ModuleA smallestoutput energy (10J x 10 H_2) HALNA (High Average-power Laser for Nuclear-fusion Application)-10 DPSSL driver module was destgned. A jet-water cooled laser-diode (LD) array was newly developed which is also useful to pump the future HALNA DPSSL.Then an evaluation method with thermal effects was developed for high-power LD arraysA high-everage power 100-W class DPSSL als … More o developed for IFE as well as for industryOutpul cliaracterisus of constructed HALNA-10 DPSSL were measured in deail, and a good agreement with the theoretical calculation was obtained. However, in oder tu reallze the 10 Hz operation, st is turned out that the thermal lens effect should be compensated forTo tompensate for the thermal btrefringence, It was shown that a quarter wavelength plate was useful for the DPSSL of less than 10W average powerA polarimeter to measure the 2D distribution of thermal birefrigence in the laser medium and the active optical elements, was newly developed3D thermal effects slab code (THESLAC) was tmproved and this THESLAC code explained the experlmental results3. Designlog HALNA-10〜20 DPSSL (10J〜20J×10 H_2) was designed, and it was shown the 10J〜20J output energy at 10 Hz will be acheaventBy use of the THESLAC code, a HALNA-10〜20 DPSSL (10J〜20J×10 H_2) was designed, and it was shown the 10J〜20J output energy at 10 Hz will be acheavent4. Conipensatlon of Therinal Birefrigence in the Faraday Rotator and Pockels CellWheti passing the 100 W〜1 kW 1053-nm laser light through a Faraday rotator glass, a depolarization loss over 10 % was expected experimentalty. However, such depolatization loss will be compensated for by use of a 67.5-degree quartz rotator between Faraday glassesIt was shown that the thermal birefringence, generated when passing the 100W class laser light at 1064 nm, can be compensated for by use of a 90-degree quartz rotator5. ConclusionIt was shown that the thermal effects generated in ihe HALNA-10 DPSSL can be comperisalable. Then, we have a confidence that next HALNA 10 〜 20 DPSSL will be operated at 10 Hz. The THESLAC code developed will be useful when developing the high-average power DPSSLs for industry Less