TY - GEN
T1 - Optimum design on thermal lensing effect of high-repetition-frequency laser based on LGS Q-switched
AU - Li, Gang
AU - Li, Li
AU - Sun, Xinhua
AU - Jin, Yezhou
AU - Mao, Shaojuan
AU - Wang, Yuanbo
N1 - Publisher Copyright:
© 2014 SPIE.
PY - 2014
Y1 - 2014
N2 - The thermal lensing effect of crystal is the biggest problem for the output of laser pulse with high power and high beam quality. Through the design of laser cavity, this effect can be removed a certain extent. In this paper, a high-repetition-frequency laser based on electro-optic Q-switch made of LGS is designed. Using flat-flat cavity, the purposes of simple structure and steady output are achieved. Firstly, using a LGS as Q-switched crystal, a Brewster plate as a polarizer, a xenon flash-lamp pumped 1064 nm high-repetition-frequency pulsed Nd:YAG laser with flat-flat cavity is demonstrated. Then, the stability of the laser cavity is analysed. Considering the thermal lensing effect of Nd:YAG crystal, the focal length of thermal lens is calculated. Utilizing MathCAD, the ABCD matrix of laser cavity is calculated, and the G value is obtained, that is G=0.792<1, so the laser cavity is steady. Furthermore, the distribution of light beam in the laser cavity is also simulated by using LAS-CAD, the results indicate that the laser works at stead state. Thirdly, the thermal lensing effect of Nd:YAG crystal is analysed by using LAS-CAD. The temperature and refractive index distributions of Nd:YAG crystal are simulated, the results show that the crystal can be equivalented as a lens with certain focal length. Furthermore, utilizing finite element analysis (FEA) method, the three-dimensional view of temperature field is obtained.
AB - The thermal lensing effect of crystal is the biggest problem for the output of laser pulse with high power and high beam quality. Through the design of laser cavity, this effect can be removed a certain extent. In this paper, a high-repetition-frequency laser based on electro-optic Q-switch made of LGS is designed. Using flat-flat cavity, the purposes of simple structure and steady output are achieved. Firstly, using a LGS as Q-switched crystal, a Brewster plate as a polarizer, a xenon flash-lamp pumped 1064 nm high-repetition-frequency pulsed Nd:YAG laser with flat-flat cavity is demonstrated. Then, the stability of the laser cavity is analysed. Considering the thermal lensing effect of Nd:YAG crystal, the focal length of thermal lens is calculated. Utilizing MathCAD, the ABCD matrix of laser cavity is calculated, and the G value is obtained, that is G=0.792<1, so the laser cavity is steady. Furthermore, the distribution of light beam in the laser cavity is also simulated by using LAS-CAD, the results indicate that the laser works at stead state. Thirdly, the thermal lensing effect of Nd:YAG crystal is analysed by using LAS-CAD. The temperature and refractive index distributions of Nd:YAG crystal are simulated, the results show that the crystal can be equivalented as a lens with certain focal length. Furthermore, utilizing finite element analysis (FEA) method, the three-dimensional view of temperature field is obtained.
KW - High-repetition-frequency laser
KW - LGS Q-switched
KW - Optimum design
KW - Thermal lensing effect
UR - http://www.scopus.com/inward/record.url?scp=84923088753&partnerID=8YFLogxK
U2 - 10.1117/12.2073230
DO - 10.1117/12.2073230
M3 - Conference contribution
AN - SCOPUS:84923088753
T3 - Proceedings of SPIE - The International Society for Optical Engineering
BT - International Symposium on Optoelectronic Technology and Application 2014
A2 - Liao, Yanbiao
A2 - Lu, Jin
A2 - Wang, Wei
A2 - Guina, Mircea
A2 - Gong, Haimei
A2 - Niu, Zhichuan
A2 - Sampson, David
PB - SPIE
T2 - International Symposium on Optoelectronic Technology and Application 2014: Laser and Optical Measurement Technology; and Fiber Optic Sensors, IPTA 2014
Y2 - 13 May 2014 through 15 May 2014
ER -