| Comparing with traditional flash lamp, diode-pumped solid-state laser(DPL) has a lot of advantages, such as lower thermal effects, higher efficiency, compactness, longer lifetime, stabilize, reliable and high power output with high beam quality. So now, it has been very promising in solid-state laser field. Single transverse mode DPLs with output power of over 100-W, even 1000-w are attractive for the applications of material processing, military tactics and ICF and have been a promising topic in this field. UV laser based on DPLs and nonlinear optical frequency conversion technology is one of the most active areas in laser technology innovations. Two parts of work are involved in this dissertation, as follows. (1) the conventional two-mirror dynamically stable resonators(DSRs), three-or four-element DSRs developed recently and the resonators with two laser heads and a 90°quartz rotator in between used for the thermal birefringence compensation of laser rods are analytical and graphical analyzed. Especially, we are the first one who graphical analyze the stability and mode characters of the the two-rod resonators with or without the 90°quartz rotator in between, when the two rods have slightly different thermal focal lengths in contrast with the condition of the same thermal focal lengths, and demonstrate that the difference will greatly affect the two-rod resonators. Then the point of view has been experimentally approved. In our two-rod resonators experiment, two 150-W(1064nm) LD pumping modules manufactured by CEO company are used, and then 265.4-W 1064nm laser output is obtained, the electric-optic conversion efficiency is about 10.3%. (2) The advantages and disadvantages of KTP crystal cut at high-temperature phase match angel and at room-temperature phase match angel have been contrastively analyzed. During the process of experiment, type-II phase match SHG KTP crystal cut at 80℃(θ=90°,φ=24.8°) is used and 111-W 532nm green laser which is the highest record in china is obtained with 1600W(808nm) LD pumping module, efficiently concave-flat resonator, at 17.7A pumping current. The conversion from 808nm laser to 532nm laser is about 10%,and that from electricity to laser near 4.6%.The AO Q-switch produced by Gooch&House company is operating at 10.6kHz,and the pulse width is 142ns.The fluctuation of 111W green laser is very small, during over ten minutes, the stability is excelled 99%. We look KTP crystal of our high-power high-repetition-rate green laser as a thin lens, when we study the resonator involved by graphical method, and demonstrate that the thermal lens effect of KTP is one of the most important factors, which affect the stabilities and mode characters greatly, the results can meet our experiment very well. in order to obtain 266nm UV laser, we use a type-I phase match BBO crystal(θ=47.6°) pumped by the green laser above and a focus lens. the spectrum of 266nm UV laser is measured by a UV spectrometer. But we can not obtain the output power for absence of available spectroscopes.
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