| Traditional laser is used of a high-pressure flash as the pump source, it spends a lotof energy in this way, short lifetime and inefficient.Until the emergence of thesemiconductor laser diode was effective in changing this situation. Due to the lowpower consumption of the semiconductor laser diode, simple structure, good beamquality emitted and high efficiency,each band of diode laser can be covered, so thelaser has inherent advantages in the application of solid-state lasers. Laser diode lasermedium and the continuous development of new materials, that bings going the highpower solid-state lasers, high beam quality, high efficiency of direction.Since the solid-state laser is used as the light beam emitted by the diode pump lighthit the end face of the laser crystal, because the light can not be completely converted tothe laser, the remaining energy will stored in the laser crystal aggregates,.that makesdifferent temperature between inside and outside. Resulting in a temperature difference,comprising causing thermal stress, thermal focal length, and the refractive index of thecrystal changes, collectively referred to as thermal effects of these phenomenon crystals.These factors will affect the stable operation of the laser, the laser can not lead to stableoperation or laser output power is reduced, the number of beam quality degradation andmode changes. The impact of thermal effects is too large to ignore, so we focus onaspects of thermal effects.The most direct way to get power is using a Q-switched pulsed laser technology,the so-called Q-switched technology is to control the storage and release of laserenergy,so that achieving the purpose of controlling the laser pulse. Q-generally dividedinto active and passive Q-tune Q, I said the study is the use of GaAs as Q-components,control the laser pulse to achieve transfer Q.The main work of this paper includes the following aspects:1. Introducing the origin of laser technology, history of emergence, development ofthe laser and making a simple classification for the laser, but describing different typesof lasers.the most important work is the characteristics and the advantages of solid-statelasers.2. Introducing the propose and evolving history of Q-technology,a simple description of the role of technology in improving Q-laser power, and the basicprinciples and classification of Q-switched technology.3. Introducing the common laser crystal material of the laser medium, andanalyzing and studying its performance parameters, such as Nd:YAG, Nd: GdVO4andNd:YVO4, talking the relevant indicators of these laser crystal.4. Analyzing the causes of the theory of laser crystal thermal effects, the use ofsquare crystal, and by building a laser crystal thermal model, listing on the thermaleffects of the Poisson equation, using the boundary conditions to analyze and solve thedistribution of thermal laser crystal. Using Matlab simulation of laser crystal internaltemperature distribution, changes in the distribution of concentration and dopinganalysis of thermal field changes according to the pump power and ion crystal material.5. Analyzing impact of thermal effects and how to reduce the influence of laserthermal effect of the laser. The main way is improving and optimizing the performanceof both the crystal.6. The use of GaAs as the Q-component into the resonator, adjusting the laser pulsewidth and peak power. By changing the transmission coupling system to studyvariations in output power and slope efficiency of size. And the different circumstancestransmittance down Q pulse width, but by changing the thickness of GaAs,wo canstudy power and pulse repetition frequency. |
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