为了获得高能量、高效率的钕玻璃前置放大器，设计了一套钕玻璃再生放大系统。通过调节单程增益和优化腔模设计，使得增益介质中的小尺度自聚焦效应得到有效控制。在重复频率1 Hz运行下，获得最大输出能量21 mJ、脉冲宽度2.65 ns的激光输出，相应的光光转换效率为5%，总增益达108，光束质量因子M2=1.5，脉冲能量稳定性均方根(RMS)值小于2%(超过2 h连续工作)，光谱的中心波长为1052.92 nm。

报道了采用激光二极管(LD)端面泵浦Nd: YVO4双端键合晶体高平均功率高斜效率1 064 nm声光调Q激光器。通过对大功率泵浦情况下激光晶体热透镜效应进行分析和估算, 优化了模式匹配及热稳腔结构参数, 实现了稳定的高功率高斜效率准连续脉冲激光输出。在泵浦功率46.8 W、最高重复频率50 kHz下, 获得最大平均输出功率17.6 W, 光-光转换效率为37.6%, 斜效率达70.1%, 脉冲宽度51.3 ns; 在最低重复频率10 kHz下, 获得最大单脉冲能量0.91 mJ, 峰值功率为46.2 kW, 脉冲宽度为19.8 ns。

通过带光纤耦合的激光二极管模块端面泵浦低掺杂浓度的Nd:YVO₄晶体,实现了高转换效率的TEM₀₀模准连续绿光激光器。实验采用平平对称腔型设计以获得大的基模体积,高衍射效率声光调Q技术以提高峰值功率密度,以及LBO临界相位匹配来实现腔内倍频。在注入功率30 W,重复频率20 kHz的条件下,获得了平均功率为96 W的532 nm激光输出,实际光-光转换效率达到334%,相应的1 064 nm基频光平均输出功率为118 W,实际倍频效率为898%。同时,测得532 nm绿光的M2因子为109,脉冲宽度为28 ns。文中还对影响绿光光束质量和转换效率的因素进行了分析。

采用光线追迹的方法研究了半导体激光二极管阵列(Laser Diode Array,LDA)抽运的耦合导光管的效率特性。分析了耦合导光管在理想情况下的反射率,并对不同参量的耦合导光管进行了模拟,得到了耦合导光管的反射率与结构参量之间的变化关系。提出了耦合导光管侧壁等效反射次数的概念,并通过光线追迹和数值拟合得到了等效反射次数与耦合导光管结构参量之间的近似数学表达式,最后通过实际工程设计实验对上述模拟进行了验证。

An optical fiber bundle array coupling module with high output power is proposed. The device integrates the coupling technique of the high power laser diode array (LDA) and the flat end-surfaces of fiber array. This module can efficiently couple the output laser of the LDA into the 19-fiber array through the flat-end surface. The fibers are ordinally fixed precisely on the V-grooves, and the fiber array has the same arrange period with the semiconductor laser units of LDA. A cylindrical fiber lens is fixed at the front of the LDA, which will greatly reduce the divergence of the laser beam and assure the laser beam to totally pass through into the end surface of fibers. High output power of 33.2 W of the fiber optic coupling of LDA is achieved, and maximal coupling efficiency is 84%.

In order to get high efficiency and high brightness laser output with single fiber coupled laser diode array, two laser diode array bars which have 40-W continuous wave (CW) output power at 980-nm wavelength are used in the experiment. The laser diode bars are collimated by two pieces of cylindrical micro lenses in the fast axis direction, and in the slow axis direction step mirrors are used to divide the beams of light to shape the output beam symmetrically. A piece of polarizing beam splitter cube is used to combine the two shaped beams. The focused output beam is coupled into a multimode fiber. More than 55-W output power is obtained from the fiber with core diameter of 400 microns and numerical aperture of 0.22, the total coupling efficiency is about 70% and the brightness is up to 10^(9) level.

报道了采用大功率国产光纤束模块端面抽运Nd:YVO4激光晶体的腔外三倍频紫外激光器, 用声光调Q技术实现了高功率高光束质量基频光输出。采用LBO Ⅰ类相位匹配和LBO Ⅱ类相位匹配的腔外倍频方法, 并利用凹面反射镜的方式进行聚焦, 避免了1064 nm和532 nm激光聚焦时由于波长的不同而产生的色差效应, 有效地提高了三倍频的倍频效率。最终在注入抽运光功率为23.3 W, 声光调Q激光器的调制频率为20 kHz的工作条件下, 基频光输出功率为7.28 W时, 得到紫外激光输出功率为1.86 W, 1064 nm基频光到355 nm紫外激光的光-光转换效率为25.5%, 此外, 对紫外激光光束质量的测试表明, 该紫外激光器具有高功率输出的同时仍有很好的光束质量。