METHOD OF CHANGING REFRACTIVE INDEX OF SOLID MATERIAL

摘要

PROBLEM TO BE SOLVED: To provide a method of changing the refractive index of a solid material in a desired region and form and with desired change rate by irradiating the solid material with pulse laser light. SOLUTION: The pulse width of the pulse laser light is changed continuously and/or in steps, and in particular, the pulse laser light is condensed to irradiate the inner part of the solid material and the pulse width is changed between 10 fsec to 10 psec. The wavelength of the pulse laser is controlled to be different from the intrinsic absorption of the solid material.