ABLATION OF THE CORNEA AND SYNTHETIC-POLYMERS USING A UV (213 NM) SOLID-STATE LASER

In this paper, we studied photoablation of the porcine cornea and synthetic collagen with 213 nm radiation generated by the fifth harmonic from a Q-switched Nd: YAG laser. The new nonlinear crystals, beta barium borate (BBO), with specific angle cutting were used to optimize the fifth harmonic generation (213 nm). For comparison purposes, the above materials were also ablated by 266 nm (fourth-harmonic) laser radiation. Light and electron microscopy demonstrated that the damage zone created by 213 and 266 nm radiation are < 1 and 15-mu-m, respectively. The ablation similarity between 193 and 213 nm demonstrated in our paper opens major opportunities for the development of a new corneal sculpting system based on solid-state laser technology which will overcome difficulties associated with excimer laser.