REFRACTOMETER Russian patent published in 1995 - IPC

FIELD: optical instrumentation. SUBSTANCE: refractometer has illuminator, element of disturbed total internal reflection made of glass with high reflectivity index n_o which working face is in contact with investigated medium with reflectivity index from n_min up to n_mix which is less than n_o, photodetector, amplifier, full-wave rectifier, angle measuring device, motor, microprocessor, indicator. Element of disturbed total internal reflection is set immobile and is fabricated in the form of rectangular prism which input face makes angle [(θ)=0.5 arcsin (n_max·n-o

¹)- arcsin (n_min·n-o¹)] with working face which in its turn makes angle β 130-135 deg with optical axis of illuminator. Mirror is mounted in front of input face of prism on mobile part of angle measuring device on restoring element of electromechanical vibrator. Mirror surface of mirror is parallel to edge of prism and is displaced relative to center of rotation of mirror by value of radius of circumference described by paths of tangent lines which are perpendiculars to bisectrices of angles made by immobile center line between incident and reflected beams and each of straight center lines of beam after reflection from center lying on normal to input face of prism crossing its edge and placed at distance d·n-o¹ from this face, where d is distance between input face and edge. EFFECT: improved operational reliability. 3 dwg