Research On Slab Nd:YAG Lasers Pumped By LD

There are many advantages of laser diode(LD)pumped slab solid-state lasers,such as simple structure,stable performance,high pump-conversion efficiency,high peak power and narrow pulse width.They have a widely applications in national defense industry,radar detection,laser communication,medical equipment,industrial production and information processing,and so on.In this paper,the research status and typical pump structure of slab lasers at home and abroad are summarized.The characteristics of Nd:YAG crystal,resonant cavity theory and passive Q-switching theory are introduced.The generation mechanism of waste heat in slab laser is described and the temperature distribution inside the slab laser crystal is simulated by ANSYS.The influence of theoutput coupling mirror transmittance,pump frequency and pump pulse width on the pulse output of the slab laser was investigated by pulsed LD array side-pumped method.The passive Q-switched crystal is realizedby implanting Cr4+:YAG crystals with different small signal transmittances in the laser cavity.The effects of pump energy,output coupling mirror transmittance and pump pulse width on the output characteristics of passive Q-switched,and the characteristics of passive Q-switched pulse are discussed in detail under different pumping intensity.When the output coupling mirror transmittance is 20%,the pump frequency is 30 Hz,the pump pulse width is 300?s and the pump current is 200 A,the output energy for the free running is 89.1mJ,the output single pulse energy is 5.25 mJ,the pulse width is 38 ns and the peak power is 1.382 kW of passively Q-switched laser.