| 摘要 |
PURPOSE:To prevent cracking of an optical material by the thermal strain thereof by projecting laser light plural times to the optical material and increasing the intensity of the laser light gradually, thereby working a groove to the optical material. CONSTITUTION:The laser 6 of the prescribed intensity is first projected to the substrate 2 of an optical integrated circuit to form the groove 8. The laser light 6 of the intensity higher than the intensity of the previously projected laser light is then projected to the same groove 8. The transfer of much heat to the substrate 2 at one time is obviated by projecting the laser light 6 having successively increased intensities to the groove 8 in such a manner and, therefore, the deep groove 8 is formed without generating cracks in the substrate 2 by the heat. |
