METHOD AND DEVICE FOR MEASURING REFRACTION INDEX OF ENVIRONMENT Russian patent published in 2000 - IPC

FIELD: optical instruments, in particular, measuring refraction index of liquid or gas environment using alteration of characteristics of surface electromagnetic waves. SUBSTANCE: method involves excitation of long-distance surface electromagnetic waves in waveguide structure, which embraces environment, detection of flat electromagnetic wave which is emitted by structure, clipping long-distance surface electromagnetic waves by means of electrooptic effect for increasing substrate refraction index, and fixing value of substrate refraction index corresponding to clipping. Device has p-polarization monochrome light source, element converting flat electromagnetic wave into long-distance surface electromagnetic wave, semi-transparent metal film, photodetector, which is designed as array, and measuring instruments, focusing lens, which is located in environment over track of long- distance surface electromagnetic wave, so that it is perpendicular to emission incidental plane and substrate plane. In addition device has regulated direct voltage source, which is connected to film and flat electrode, which is embedded into substrate and is located outside of converting element in parallel to film and is spaced by distance, which is greater than penetration of field of long-distance surface electromagnetic wave into material of substrate. Substrate is made from electrooptic material. EFFECT: increased precision. 2 cl, 2 dwg