Electro-optic Q-switched intracavity optical parametric oscillator at 1.53 (mu)m based on KTiOAsO_(4)

摘要

An eye-safe, high peak power optical parameter oscillator (OPO) intracavity pumped by electro-optic Q-switched Nd:YAG laser is presented. This OPO is based on a 20 mm length KTiOAsO_(4) crystal with non-critical phase matching (0 velence 90 deg, phi velence 0 deg) cut. An aperture circle/3 mm acted as limiting diaphragm to get good beam quality of pumping laser. The output energy of 25 mJ at the signal wavelength 1.53 (mu)m was obtained with repetition rate of 1 Hz. The highest peak power intensity was up to 88 MW/cm~(2) with pulse width of 4 ns. Without diaphragm, the maximum output energy of 90 mJ was achieved with area of light spot (circle/6 mm) four times larger, but the peak power intensity was lower.