INTERFEROMETER DEVICE FOR MEASURING OPTICAL THICKNESS OF A TRANSPARENT LAYER OR A GAP Russian patent published in 2007 - IPC G01B9/02 G01B11/06 

FIELD: measuring equipment engineering, possible use for noncontact measurement of optical thickness of transparent material layers and gaps between flat-parallel surfaces of elements, one of which is required to be transparent.

SUBSTANCE: device contains light source, delay line and photo-detector. Light polarizer is mounted between the light source and the object being measured. An analyzer is mounted in front of the photo-detector. Delay line is made in form of a phase plate, normal wave phase difference of which may be tuned. The phase plate is mounted in such a way that its normal wave polarization plane makes a 45° angle relatively to polarizer axis direction. Analyzer and photo-detector are made with possible visualization and registration of interference pattern meant for determining the optical thickness of the object being measured.

EFFECT: increased precision and sensitivity of optical thickness measurements.

4 cl, 5 dwg