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61.
A high-efficiency high-power Nd:YAG laser under 885 nm laser diode (LD) pumping is demonstrated. The laser crystal is carefully designed, and the overlapping between the pump modes and the laser modes is optimized. The maximum output power at 1064 nm is 87W under the absorbed pump power 127.7 W, corresponding to a slope efficiency of 72.4% and an optical-optical efficiency of 68.1%. The optical-optical efficiency is 58.4% for the pump power emitted directly from the LD. To our best knowledge, this is the maximal optical-optical conversion efficiency obtained for the LD end-pumped Nd:YAG lasers so far. 相似文献
62.
63.
High-power ultraviolet 278-nm laser from fourth-harmonic generation of an Nd:YAG amplifier in CsB_3O_5 crystal 下载免费PDF全文
We report on the experimental investigation and theoretical analysis of a nanosecond pulse high power ultraviolet(UV) 278 nm laser by fourth-harmonic generation(FHG) of a 1112-nm Nd:YAG amplifier in LiB_3O_5(LBO) and CsB_3O_5(CBO) crystals. The UV laser delivers a maximum average power of 10.3 W at 278 nm with peak power of 36.8 k W under input pump power of 41 W at 556 nm. This is, to the best of our knowledge, the highest output power at the specific UV wavelength of 278 nm. We also performed the theoretical investigation on the FHG with a model in the Gaussian approximation of both spatial and temporal profiles, especially accounting for the two-photon absorption effect in CBO crystal for the first time. The average output power, pulse width, and beam spatial distribution of the UV laser were simulated. The theoretical calculations are in close agreement with the experimental results. 相似文献
64.
A high power continuous-wave (CW) diode-pumped Nd:YAG laser operated in heat capacity mode is demonstrated by use of two identical highly efficient diode-pumped laser heads placed in a plane-plane resonator.The laser heads are uniformly pumped with a five-fold symmetrical side-pumping configuration, and each head is able to output maximum output power of 2200 W at 808 nm.Under a total pump power of 4290 W,the output power of the laser at 1064 nm is up to 2277 W,corresponding to an optical-to-optical efficiency of 53.1%. 相似文献
65.
66.
非线性光学相位共轭技术可将经过散射介质后产生畸变的光学波前进行修复.本文基于光参量放大(OPA)过程的光学相位共轭(OPC)特性,进行了光学相位共轭图像修复和增强的实验研究.基于大能量532 nm皮秒抽运激光和大口径非线性光学晶体KTiOPO_4(KTP)(Ⅱ类相位匹配),对经过牛奶乳浊液后已无法识别的1064 nm近红外光学图像,进行相位共轭修复,修复后的图像分辨率达12线/mm,此外,结合OPA过程的光学增益特性,实现了超过17 dB的光学图像增强,为现有三波混频光学相位共轭修复畸变所获图像增益的最大值.在此基础上,峰值信噪比较修复之前有160%的提升.考虑到光参量过程所具有的波长可调谐特性,在实际应用中,可根据需要,选择与生物组织的光学治疗窗口相匹配的成像波长,从而保证更长的穿透深度,提升生物组织成像和医学无损检测的效果. 相似文献
67.
High power high beam quality diode-pumped 1319-nm Nd:YAG oscillator-amplifier laser system 下载免费PDF全文
This paper demonstrated a high power and high beam quality
diode-pumped 1319-nm Nd:YAG master oscillator-power amplifier laser
system. A thermally near-unstable resonator with four-rod
birefringence compensation flat--flat cavity was adopted as the
master oscillator. A solid etalon was inserted in the unidirectional
ring resonator to compress the laser linewidth. Under a repetition
rate of 500~Hz and pulse width of 160~\mus, the master oscillator
delivers an average output power of 16.8~W at 1319~nm with linear
polarisation, beam quality factor M^{2} = 1.16 and linewidth of
3.2~GHz. A double-pass power amplifier with two amplifier stages was
employed for higher power scaling and the output power was amplified
to be 25.9~W with M^{2} = 1.43. 相似文献
68.
研制了高功率可调谐1064 nm准连续单频激光振荡-放大系统.振荡级采用三镜环形行波腔型结构的Nd:YAG激光器,通过精确控制腔内标准具的温度改变标准具材质折射率和厚度实现了对激光波长的调谐,获得了13.2 W调谐范围为58 GHz的1064 nm准连续单频振荡光,其重复率为1 kHz,占空比为10%.经过由双Nd:YAG激光头串接构成的放大器对振荡光进行双程放大后激光最终输出功率为44 W,光束质量因子M2= 1.58.
关键词:
可调谐激光
单频激光
标准具
振荡-放大系统 相似文献
69.
EFFECTS OF THE QUALITY OF SUBSTRATE ON THE STRUCTURE AND SUPERCONDUCTING PROPERTIES OF Yba2Cu3O7-x THIN FILM 下载免费PDF全文
We have systematically investigated the structures, morphologies, microwave surface resistance, DC performances and the substrate qualities of three YBa2Cu3O7-x(YBCO) thin films 30mm in diameter. The three samples deposited by the same process have been proved of different properties. It has been shown that the structure and superconducting properties of the thin film depend strongly on the quality of substrate. 相似文献
70.