Research Of All-solid-state Raman Laser

Yellow laser in the range of 550nm-600 nm is in eye-safe range wavelength,which have important applications in various fields.Stimulated Raman scattering(SRS) is an effective method to obtain yellow laser.In this paper,.the operation thleshold of the external-resonator Raman laser is theoretically predieted by numerieal method and all-solid Raman laser is obtained. Through a spectroscopical device system,we found the maximum conversion efficiencies of the first Stokes is 30.03% and the maximum energy is 1.3m J, the maximum conversion efficiencies of the second Stokes is 14.5% and the maximum energy is 0.6m J. Paper works are as follow:(1) The working characteristics of Raman laser is theory simulation analysised. Then, the pump pulse wdith,beam quality factor,waist radius,the reflectivity of the output coupling mirror for pump and first order stokes light,Raman resonant cavity one-way loss coefficient effect on the influence of the Raman threshold power is analysised and discussed.(2) A all-solid-state Raman laser is designed. An Electro-optic tuning Q-Type Nd:YAG solid pulsed laser is designed in order to obtain the laser at 550nm-600 nm wavelength.The pumping source has a plane concave type stable cavity structure.The wavelength of pumping source is 532 nm and the repetition frequency can be available at 1Hz、5Hz、10Hz、20Hz.The maximum single pulse energy of 532 nm green laser is 150 m J,pulse width is about to 20 ns and divergence angle is less than 4 mrad.(3) On the basis of the stability of green light output, the stimulated Raman scattering experiment was completed. In the experiment, the energy which were strong of the first Stokes light and second Stokes light and the energy which is weak of the third Stokes light were obtained. Their wavelength were respectively 563 nm,599nm and 638 nm. Through a spectroscopical device system, the energy and pulse width of the first and second Stokes light were measured and we found the pulse compression phenomenon of Stokes light was exited. The conversion efficiencies of the first and second Stokes light were calculated, the maximum conversion efficiencies of the first Stokes is 30.03% and the maximum energy is 1.3m J, the maximum conversion efficiencies of the second Stokes is 14.5% and the maximum energy is 0.6m J.