OPTICAL-ELECTRONIC DEVICE WHICH MEASURES POSITION OF ANGLE METER DIAL Russian patent published in 1997 - IPC

FIELD: instruments. SUBSTANCE: device has lens, light sources, aperture, scanning unit, disk with two slits on its periphery, photo diodes, bar scale and electronic circuit for information conversion. Bar scale is designed as obscure disk with transparent slits. Scanning unit is designed as two-side optical wedge. Light source has two light-emitting diodes and aperture which has two point-like holes which are located on line that is perpendicular to plane of rotation axes of dial, scanning unit and optical axis of lens. Distance between lens-generated pictures of holes in aperture on disk periphery is equal to odd number of halves of spaces between bars. Two photo diodes which are located between these pictures are connected to first inputs of units of two-channel electronic circuit. Second inputs of these units are connected to photo diode which is located above disk with two slits. Said units have amplifiers, pulse generators and meters of intervals between pulses. In addition input units are connected to generator of high-frequency filling pulses; their outputs are connected to microcomputer for calculation of angular deviation. Latter outputs are connected to unit for detection and comparison of absolute values, switching and indication of results. EFFECT: increased precision, increased field of application. 2 dwg