Method for changing the refraction index in germanium silicate glass

摘要

The present invention relates to a method for changing the refractive index in an element comprising germanium silicate glass by irradiating the germanium silicate glass with laser radiation having an associated wavelength in the range of 270 nm to 390 nm for exciting an absorption band in the glass centered at 330 nm. The element may be polymer coated in which instance the glass is irradiated through the polymer coating. In addition, the glass may have been exposed to a hydrogen atmosphere before being irradiated. In either instance, the laser radiation is directed at an angle to the surface of the element or along an optical axis of the element or both. The element may comprise a portion of an optical light guide, such as an optical fiber, or such as an integrated optical waveguide.