Investigation of thermal induced diffraction loss on Q-switched intracavity optical parametric oscillator

In this paper the influence of thermal induced diffraction loss on the optical parametric oscillator has been investigated numerically by analysing the rate equations model. The model has been performed to the practical example of Q-switched Nd:YVO4-KTA optical parametric oscillator to verify the theoretical model. The numerical analysis shows that the signal output power can be maximized for unique pump beam radius. The pump beam radius is calculated to be 297 μm which is reported 300 μm from experimental results.