Research on Thermal-Effect and Phase Properties of a Q-Switched Laser Using KTP Frequency-Doubling Crystal

Abstract:

Results of an experimental and theoretical analysis of the proprerties of a LD pumped laser using a plano-concave stable resonator and KTP frequency-doubling crystal material are presented. The influence of thermal lens effect on laser output mode and beam quality has been discussed briefly by using the transfer matrix theory. In this paper, further experiment on the output beam quality of a LD pumped acousto-optic Q-switched laser has been also performed by adopting Hartmann-Shack wavefront sensor and Zernike mode reconstruction theory. Using this method, the PV and RMS values of the aberration wavefront, the frontal 35-order Zernike aberrations can be acquired, and the Strehl ratio curve of the output beam and the distribution of circle energy can also be obtained by calculation, so the mode properities can be fully understood. The experimental results show that the beam wavefront aberration is mainly concentrated in the frontal 15 orders of Zernike aberration, mainly including the defocus A₃, the low-order astigmatism A₄ and A₅, and the coma aberration A₆ and A₇ because of crystal thermal effect.

• Periodical: Advanced Materials Research (Volumes 282-283)
• Pages: 505-508
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.282-283.505
• Online since: July 2011
• Authors: Xiang Zhang
• Keywords: Crystal Thermal Effect, KTP Frequency-Doubling Crystal, LD Pumped Solid-State Laser, Wavefront Properites, Zernike Aberration

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