Meassurement of the laser diode end-pumped solid laser''''s thermal focal length by using the curve of output
利用输出功率测量激光二极管端面抽运的固体激光器热透镜焦距

A U like shape on the curve of fundamental mode waist in the active medium versus pump power, at different cavity lengths of the laser diode (LD) end pumped Nd:YVO 4 solid state lasers with a flat flat resonator structure, is analyzed by means of the transform circle approach. There are caves and pinnacles on the curve at appropriate cavity lengths. Utilizing the caves and pinnacles, a new method is put forward to determine the focal length of thermal lens. Based on the theoretical analysis, we have designed a laser and obtained some experimental results that are consistent with the theoretical expectations.