NEW APPROACH FOR LOSS MEASUREMENTS IN OPTICAL PLANAR WAVEGUIDES

摘要

A new nondestructive method for measuring waveguide losses is presented. It uses a prism-in coupling method to feed the light into the waveguide and the end-fire coupling to measure the transmitted light. It is simple both in construction and during the measurements. Such a configuration enables us to determine the attenuation coefficient which is independent of coupling efficiencies into and out of the guide and of the laser fluctuation. The results obtained, with this method, on H+ and He+ implanted LiNbO3 waveguides are presented and discussed. Therefore, the measurements lead to the calculation of the attenuation with an absolute incertitude of 0.4 dB cm(-1) for a waveguide length of 0.4 cm. [References: 21]