Mixed With Cr~ ( 4+ ) : Study On Tunable Laser Yag

As the gain-medium, the emission spectrum of Cr~4+:YAG ranges from 1.3 to 1.6 μ m.This unique wave band is the so-called eye-safe region and has low loss and low dispersion for optical fiber. So lasers of this wavelength range are widely used in the fields of laser radar, free air and optical communication. This dissertation present theoretical and experimental research on tunable Cr~4+:YAG laser end bumped by LD .The contents can be described as follows:1. Review the history of tunable laser. Meanwhile a simple recommend on the main uses and development of the crystal Cr~4+:YAG and the Cr~4+:YAG laser has been made.2. Based on the space-dependent four-level rate equation theory, the output properties of LD end-pumped solid-state lasers are analyzied. The mode-overlap between pumping mode and oscillating mode is studied and numerically simulated on the dimension and position of focusing spot, the angle of pumping laser divergence and the transmission rate of output mirror. These provide a theoretical basis and guide of our experiment.3. Analyze the temperature distributing in the crystal. Several methods to measure the thermal-focus and compensate the thermal effect are also summarized.4. Based on the cavity propagation matrix theory,the selection of cavity parameter and the transmission characteristics of gaussian beam inside the rasonators are analysed at large.5. The diverce of diode-pumped is given. The tune range is 100 mw, from 1460 to 1560nm .The threshold is 1.5w and a continue maximum output power of 243 mw is obtained with the slop efficiency of 6%...