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

1.激光二极管泵浦的高平均功率固体激光驱动模块用于激光聚变能时，需要对激光介质和有源光学元件中的热效应，如热透镜效应、热双折射效应和热变形效应进行补偿。本文首先开发了三维热效应分析程序，并通过与实验结果的对比，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）的驱动模块。DPSSL驱动模块的设计、研制和评价设计了一个输出能量最小（10 J × 10 H_2）的HALNA（高平均功率核聚变激光器）-10 DPSSL驱动模块。本文介绍了一种新研制的用于泵浦HALNA DPSSL的激光二极管（LD）阵列，并在此基础上提出了一种考虑热效应的高功率LD阵列的评价方法。 关于我们 本文对HALNA-10型DPSSL的输出特性进行了详细的测量，并与理论计算结果进行了比较。为了实现10 Hz的工作，必须补偿热透镜效应，以补偿热双折射。本文指出，对于平均功率小于10 W的DPSSL，四分之一波片是有用的。对新开发的三维热效应平板程序（THESLAC）进行了改进，并对实验结果进行了解释。设计了HALNA-10 × 20 DPSSL（10 J × 20 J × 10 H_2），得到了10 Hz下10 J × 20 J的输出能量。法拉第旋光器和泡克耳斯池中的双折射实验研究当100 W × 1 kW的1053 nm激光通过一个法拉第旋光器玻璃时，实验预期退偏损耗超过10%。然而，这种去极化损失将通过在法拉第玻璃之间使用67.5度石英旋转器来补偿。已经表明，当1064 nm的100 W级激光通过时产生的热双折射可以通过使用90度石英旋转器来补偿5。结论HALNA-10型DPSSL的热效应是可以接受的。那么，我们有信心，下一个HALNA 10 - 20 DPSSL将在10 Hz下运行。所开发的THESLC程序对工业用高平均功率DPSSL的开发具有一定的参考价值

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