Study On Continuous Tm Laser Pumped Ho Laser

2μm laser provides with broad applications in spectra analysis, laser target detecting, laser remote sensing, medical diagnoses and therapy, photoelectricity countermeasure, optical signal disposing, data disposing, material disposing, environment monitoring of Differential Absorption Laser Radar (DIAL) and so on.This thesis analyzed the output characteristics of Ho laser pumped by continuous Tm laser. The rate equation of Ho laser in continuous-wave operation and Q-switched operation was put forward. The rate equation was solved to analyze the influence of upconversion effect to the output power, slope efficiency and threshold power in CW operation and the pulse energy, pulse width and peak power in Q-switched operation. The transition branching ratio between the energy levels was taken into consideration for the first time while discussing the influence of up conversion. The characteristics of Ho laser were simulated under the condition that the incident pump power was30W, the dope concentration of Ho3+ in Ho:YAG was1%, the crystal length was10mm, the reflectivity of output coupler was90%, the cavity loss was0.05, the cavity length was10cm. In continuous-wave operation, ignoring the upconversion, the threshold power was1.287W, the output power was18.65W, the slope efficiency was64.97%, while considering the upconversion, the threshold rised0.38W, the output power reduced4.44W, the slope efficiency reduced14.83%, were1.667W,14.21W,54.14%, respectively. In Q-switched operation, ignoring the upconversion, the pulse energy was25.7mJ, the pulse width was3.993ns, the peak power was18.19MW, while considering the upconversion, the pulse energy reduced6.15mJ, the pulse width rised1.139ns, the peak power reduced7.33MW, were19.55mJ,5.132ns,10.86MW, respectively. The consequence of simulation was consistent with the output characteristics of Ho lasers in articles.