A Reaserch Of The Wide Temperature Rang Miniaturization Eyesafe Laser

A miniature diode pumped passively Q-switched Er3+, Yb3+ co-doped phosphate glass laser is designed. The centre wavelength of laser is 1535 nm that is safe to human eyes, simultaneously owing to many advantages such as compact structure, small volume and easy to carry, has wide application requirements in ladar, rangefinders, medicine and optical communications. The main research contents of paper are as follows:1. Based on the theoretical analysis of Er3+/Yb3+ co-doped phosphate glass three- level system rate equation, we calculate some parameters of the laser, such as pump spot radius, optimal pump position and the influence of round-trip loss.Consider Yb3+ ions sensitization effect in Er3+ /Yb3+ co-doped phosphate glass crystals. As Er3+ concentrations is confirmed, Yb3+ determines the pump absorption efficiency. We calculate the optimal length of the gain medium to pump energy according to small signal gain formula.2. Summarise and compare the advantages of 1.5μm passive Q-switch crystals, We selected Co2+:Mg Al2O4 as Q-switch. Based on the Q-switch theory of Degnan, we simulate the optimal output mirror reflectivity of different initial transmittance.3. There are two considered points about the structure design of the laser. Firstly, compact, miniature and integration; secondly, heat dispersion. The laser structure is vacuum packaging and successful running in the temperature range. To improve stability of laser output in a complex environment, and convenient to carry.4. On the basis of theoretical analysis in the paper, we select that the center wavelength of pump source is 940 nm. The Co2+:Mg Al2O4 crystal is used as saturable absorber. As the pump energy of 9 m J, repetition frequency of 10 Hz, pump duration of 5ms, the pulse energy of 130μJ, pulse duration of 5.5ns, peak power of 20 k W, wavelength of 1535 nm and beam quality M2 of 1.3 was obtained. The line width is less than 0.02 nm.The output instability is less than 5% by natural cooling way. The laser can also be derived by the lithium battery for further application, such as field environment.