Study of thermooptic distortions of a Nd:YVO4 active element at different methods of its mounting

Thermooptic distortions of the active element of an axially diode-pumped Nd:YVO₄ solid-state laser are studied at different methods of its mounting. The study was performed by the Hartmann method. A mathematical model for calculating the optical power of a thermal lens produced in the crystal upon pumping is developed and verified experimentally. It is shown that the optical power of a thermal lens produced upon axial pumping of the convectively cooled active element sealed off in a copper heat sink is half the optical power observed upon convective cooling of the active element without heat sink. The experimental and theoretical results are in good agreement.