High Repetition-rate, High Peak-power Eye-safe Laser

OPO as a kind of high coherence tunable laser source has been attracting many researchers for its unique characters. Recently, with the development of nonlinear frequency conversion crystal and solid-stale laser technology, research activities in this area are heating up. The research on KTP-OPO system lasing at 1.57μm eye- safe wavelength is one of the favorite topics. Currently, the laser radar, laser imaging, medical and other fields has requested eye-safe laser with high repetition rate, high peak power, which makes high repetition rate, high peak power eye-safe laser (KTP-OPO) becomes a research hotspot. By using a typeâ…¡nontrivially phase-matched singly resonant KTP-OPO system, laser at1.57μm can be achieved. In this paper,the results of theoretical and experimental researches on KTP-OPO at the eye-safe wavelength are Presented. The main contents of this dissertation as follows:1. Summarized the optical parametric oscillator's (OPO) development history, advantages and this research project's significance, describes, the use of technology to obtain eye-safe OPO laser, the development of status and problems it's have, then point out the trend of OPO.2. The threshold parameters, conversion efficiency and band-width of the OPO are theoretically studied by considering the coupling equations of three nonlinear frequencies mixing. The OPO operation conditions and the configuration are summarized in the end.3. A high repetition rate, high peak-power electro-optic Q-pumped Nd:YVO₄ laser was designed as a pump scours and analyzed the test results of its output performance indicators .4. Summarized the optical properties of KTP nonlinear crystal, OPO phase matching, and analysis the design of KTP-OPO which obtains the output eye-safe laser wavelength, and high repetition rate, high peak-power eye-safe laser external cavity KTP-OPO design is given, then simulated the technical parameters of OPO in theoretical, including: the threshold pumping power density, the best pump power density, and gives the relations between the two of OPO design consideration.5. Experimental research and performance testing have did for the high repetition rate, high peak-power external cavity eye-safe laser which we designed, including: the wavelength, pulse width, energy, output performance stability, beam quality, then analysis of experiments and test results.