Study On Pr Doped Solid State Laser

All solid-state lasers in visible band are developing rapidly,among which600nm-660 nm lasers are widely used in color display,printing,medicine,and laser communication,etc.For the all-solid-state laser in visible band,the nonlinear frequency transformation is mainly used to convert near-infrared light at 1064 nm and946nm into second or third harmonics.This paper mainly studies the direct generation of visible light by LD end-pumped Pr-doped solid state laser through theoretical research,simulation and experimental exploration.The specific research content is as follows:(1)According to the four-level rate equation,the influence of the spatial overlap of the pump light and the oscillating light on the output characteristics of the laser is deduced,and the mode matching of the laser is studied from the Angle of spatial geometric overlap of the pump light and the oscillating light.(2)According to the theory of thermal effect,the thermal effect model is established,the temperature field inside the crystal is analytically calculated,and the distribution expression of the temperature field inside the crystal is obtained.Through finite element analysis,the thermal effect of LD end-pumped PR-doped crystal was simulated,and the influence of different factors on the temperature field distribution of PR-doped crystal was simulated and analyzed.(3)A 1W LD end-pumped Pr-doped solid state laser was designed.Using 1W444 nm LD as pump source,the output characteristics of LD were studied,and the simulation was carried out.The LD beam is directly coupled by a single lens,and the coupled beam is analyzed by ray tracing.The optical path of the resonant cavity is designed,and the stability of the plane-concave cavity is analyzed.The laser crystal and cooling system were designed.Finally,the experimental study of a 1W LD endpump Pr-doped solid state laser was carried out,and the laser output characteristics were measured.(4)A 2W LD end-pumped Pr-doped solid state laser was designed.Using 2W444 nm LD as pump source,optimize the design of Pr-doped solid state laser.The flat-convex lens was used to shape and coupling the LD beam,and the laser output characteristics were measured,the highest output power is 266 m W and the optical conversion efficiency is 15.1%.In order to further increase the output power,the LD beam shaping system was optimized by using a cylindrical lens combination.With the output mirror transmittance of 3.5%,the maximum output power was 298 m W and the opto-optical conversion efficiency was 16.9%.