光技術情報誌「ライトエッジ」No.14(1998年10月発行)
CLEO®’98 Conference on Lasers and Electro-Optics
(1998年 5月3日～8日)
CPD4-1
200mW 192nm Generation using CsLiB6O10 Crystal
K.Deki, J.Sakuma, Y.Ohsako, N.Kitatochi, T.Yokota, and M.Horiguchi, Tsnkuba R&D
Laboratory, Ushio Research Institute of Technology Inc.
5-2-4 Tokodai, Tsnkuba 300-26
Phone:0298-47-9072
Email:dekikic@mail.ushio.co.jp
Y.Mori, and T.Sasak
Department of Electrical Engineering, Osaka Uuiversity
2-1 Yamadaoka, Suita, Osaka 565
(Abstract)
More than 200mW average power at 192nm was obtained at repetition frequency of 100Hz using CLBO as the final sum ferequency mixing crystal. In the operation of 10Hz 3.8mJ/pulse at 192nm was obtained.
CPD4-2
200mW 192nm Generation using CsLiB6O10 Crystal
K.Deki, J.Sakuma, Y.Ohsako, N.Kitatochi, T.Yokota, and M.Horiguchi, Tsnkuba R&D
Laboratory, Ushio Research Institute of Technology Inc.
5-2-4 Tokodai, Tsnkuba 300-26
Phone:0298-47-9072
Email:dekikic@mail.ushio.co.jp
Y.Mori, and T.Sasak
Department of Electrical Engineering, Osaka Uuiversity
2-1 Yamadaoka, Suita, Osaka 565
(Summary)
More than 200mW average power at 192nm was obtained at repetition frequency of 100Hz using CLBO as the final sum ferequency mixing crystal. ln the final mixing stage 1.96 μm output of the OPO was mixed with the fifth harmonic output of Nd:YAG Iaser as shown in Fig.1.The second, fourth, and fifth harmonics of Nd:YAG Iaser was generated by BBO, CLBO, CLBO, respectively. As the Nd:YAG fundamental laser has a top-hat beam , relay imaging was used to suppress the phase distortion of the beam as small as possible.
In the operation of 10Hz 3.8mJ/pulse at 192nm was obtained as shown in Fig.2(a). However this 192nm output energy decreased to 2.1mJ/pulse at re-petition of 100Hz as shown in Fig.2(b) probably because of increasing thermal dephasings at high repetition in each crystal, especially in the final mixing , 4HG and 5HG crystals.The overall conversion efficiency(fundamental to 192nm energy) was 1.5% and 0.85% at 10Hz and at 100Hz, respectively.
The performance comparison between CLBO(Type2) and LBO(Type1) in the final SFM stage was also experimented. As a result CLBO generated larger power than LBO at both 10Hz and 100Hz operation frequencies. Taking into account the relatively larger effective nonlinear optical coefficient and the acceptance temperature band width of CLBO than LBO, this result is reasonable.
CPD4-3
CPD4-4
参考文献
Introduction
Output Energy in each stage
CLBO/LBO as the final SFM crystal
Conclusion
