Measurement of internal spatial modes and local propagation properties in optical waveguides

Internal spatial modes and local properties controlling optical wave propagation have been measured in glass/silica buried waveguides. The period of the observed standing modes provides a direct measure of the local effective index. The measured effective index and transverse model shape determines the values of all components of the wave vector. In addition, we describe a technique that can obtain detailed information about the locations of remote dielectric interfaces.