Analysis of transient temperature distribution in laser rod pumped by repetitively pulsed highpower ring-LDA

The transient temperature distribution in the Nd:YAG laser rod repeatedly pulsepumped by high power ring-LD array was simulated in detail by using ray tracing method and finite element method. The transient temperature distributions at different pump periods, pump frequencies and pump widths were analyzed and compared. The result indicated that when high power ring-LD array pumped repeatedly, the core temperature of the rod had sawtooth distribution，and the temperature of the rod rose as the pump frequency or pump width rose. At last the temperature had periodical distribution with time．