Accession Number : ADD012934

Title :   Total Internal Reflection Modulator/Deflector.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE AIR FORCE WASHINGTON DC

Personal Author(s) : Birnbaum,Milton ; Tucker,Armin W ; Tucker,Marsha A

Report Date : 02 Jun 1987

Pagination or Media Count : 7

Abstract : A total internal reflection modulator/deflector assembly for use with a focused beam of polarized incident laser light. The application of a low direct current voltage (e.g., less than 50 volts) to a pair of identical stacked crystals exhibiting the Pockel's effect produces an index of refraction difference at their interface. Since the index changes are small, the incidence angle of the impinging polarized laser light is large, e.g., 89 degrees. In the preferred embodiment, one crystal is rotated relative to the other, such that the applied electric field causes index changes of + delta n in one crystal and of - delta n in the other crystal. As a result, the impinging polarized laser light is divided into two portions, one of which is totally internal reflected, and transmitted in the desired modulated conditions. Two electrode members are used to apply the low direct current voltage to the interface of the crystals, with the electrodes arranged to face that the incident light need not traverse them, the other portion is refracted.

Descriptors :   *PATENTS, *ELECTRIC FIELDS, *DEFLECTORS, *INTERNAL REFLECTION, *MODULATORS, *POCKELS CELLS, *CRYSTALS, ELECTRODES, INDEXES, DIRECT CURRENT, LOW VOLTAGE, REFRACTIVE INDEX, LASER BEAMS, MODULATION, STACKING

Subject Categories : Optics
      Crystallography
      Electricity and Magnetism

Distribution Statement : APPROVED FOR PUBLIC RELEASE