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Laser diode (LD) pumped solid-state lasers with high efficiency, good beam quality, compact, long life, etc., in the military, medical, information, research and other fields have a wide range of uses. Among them, the erbium-doped glass laser media laser can emit 1.54μm near co-doped Yb 3 can greatly improve the laser efficiency. Such lasers are widely used in optical communications, optical sensing, eye-safe laser rangefinder and so on. In this paper, LD end-pumped Er 3 / Yb 3 co-doped phosphate glass laser is a solid theoretical analysis and experimental research, to obtain the maximum output of 30mW 1.54μm laser light - optical conversion efficiency of 1.6%. Specific studies are as follows: 1. According to the rate equation theory 1.54μm laser operation rate equation model, and derive the steady-state operation threshold pump power, output power, slope efficiency. On Er 3 / Yb 3 laser rate equations for three-level system analysis, the cavity length, the transmittance of the output mirror, the pump beam radius, cavity round-trip Power dissipation on input-output relationships and threshold values. The optimum conditions obtained laser operation. (2) specifies the design of the coupling lens group the way, has been the beam waist position, beam waist radius changes with the relationship between the object distance s1; beam waist location, average pump beam radius inside the crystal and the variation of the coupling lens focal length. 3 using the ABCD transmission matrix of the active flat cavity, concave cavity numerical calculation, analysis resonator cavity laser spot and stability. Draw resonator oscillation beam radius, stability parameters and input power, the relationship between the thermal lens focal length, stability parameters and the variation of the cavity length; determine the cavity length in 20mm 6 0mm the most stable, pump power is less than 10W, the concave cavity stability gifted with flat cavity, concave cavity spot radius ω values ??smaller and slower change. 4 In the theoretical analysis, based on a fiber-coupled semiconductor laser as the pump source, Er 3 / Yb 3 co-doped phosphate glass as the working medium, successfully achieve flat cavity, concave cavity at room temperature, continuous output 1.54μm laser. Considering meniscus output mirror for beam quality improvement, this paper also uses meniscus output mirror conducted experiments obtained when the input power is 3.05W of 1.54μm laser 30mW continuous output.
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