Low cost, air cooled, 7 W 8 ns 60 kHz, infra-red laser for industrial marking application with doubling and tripling frequency module

The objectives were to provide a low cost, air cooled and robust laser. Nd:YVO/sub 4/ crystal is now a current choice as a lasing material for diode-pumped solid state laser because of its high gain, high absorption and also linearly polarized output. However its poor thermal properties and its fragility, compared to Nd:YAG, are disadvantages for industrial applications. Composite crystals with adhesive free bonding are good solutions to reduce thermal lensing and improve crystal robustness. Results obtained with a segmented Nd:YVO/sub 4/ crystals manufactured by FEE with a new technology bonding are presented and the advantages of this technology will be discussed.