Investigation Of Pulse Stretching In Electro-Optical Q-switched Ruby Laser

The laser Q-switch technology is the technology which compresses all the energyof laser into very narrow pulse, and increase pick power by several levels. After theintroduction of this technology in 1961, it was rapidly developing, has also expediteddeeply research in power output and compress technology of pulse width for laserdevice.It's very hard to control the width of the laser during laser application, and nowlaser technology normaly can only obtain the laser pulse of several nanosecond ormillisecond, therefore it could have only limited number of fixed wavelength andpulse energy. So laser pulse strutching research is propitious to extend domain of laserapplication, specially in the field of laser medicine and laser machining can beused very widely. On international from 1980 to 1999 W.E. Schmid and PatrickRambo, Jens Schwarz,etc had researched laser pulse stretching. In the Nd: YAGlaser and alexandrite laser obtained laser pulse of 600ns and 1.7us width.According to new requirement of the development of laser technology we havedone relational researchs of electro-optical Q-switched ruby laser pulse stretching.The main task of this research is the design of Q-switched ruby laser resonator andelectro-optical Q-switched driver circuit, the study of experiment technology. Morethen we have achieved up to 700ns ruby laser pulse. In this paper we have done thefollow work:1. Derivation of rate equation of Q-switched laser pulse stretching, analysis ofseveral elements that influence the pulse stretching. We design ruby laser resonator,which is flat-concave resonator, which use loss channel of laser resonator and outputlaser, by passing through drop-voltage process of Q-switched crystal we can obtainlaser pulse.2. Ruby Q-switched driver circuit was designed, drop-voltage wave was created.Since drop-voltage wave is complicated, xeon pump signal is divided into threesignals along with the delay, and then all were combined within 1us time, was made anew drop-voltage wave.3. During the process of the experiment, we found rules of severel key parametersthose are able to realize the pulse stretching. For instance, the main delays, the pumpvoltage, the rise time of drop-voltage wave reflect in the effectiveness of laser pulsestretching.