Nanosecond Ktp Optical Parametric Oscillator

With a wide-spectrum tunable output, optical parametric oscillator (OPO) extends the laser wavelength and meets diversified needs. Recently, with the development of good quality nonlinear frequency-conversion crystals and solid-state laser used as pump source, research activities in this area is heating up. For attaining practical OPO, enhancing conversion efficiency, extending pulse tuning scope and OPO apparatus miniature have been hot focus.In this paper, the reach actuality and development trend of OPO in-country and overseas is introduced. Also, the application of OPO is summarized.Theoretically, on the bases of the physical and chemical characters of nonlinear frequency-conversion crystal KTP, the parameters such as walk-off angel, acceptance angle and effective nonlinear coefficients are calculated, analyzed and discussed , together with elaborate analysis to phase-matching process for type II KTP OPO phase-matching.In the OPO theory, the principium of the optical parametric oscillator is explained. Then, on the basis of coupled wave equations, theoretically studies of OPO threshold parameters and of the conversion efficiency and of linewidth control are presented. Several principles of the optimum design for OPO are discussed.The experimental investigations of noncritical phase matching...