Accession Number : ADD014707

Title :   Solid State Electronic Emulator of a Multiple Track Motor Driven Rotating Magnetic Memory.

Descriptive Note : Patent, Filed 2 Jul 85, patented 18 Sep 90,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Balch, Kris S

Report Date : 18 Sep 1990

Pagination or Media Count : 29

Abstract : A method for remotely detecting the angular position of a rotatable code wheel is provided by generating two sine wave modulated light beams which are orthogonally polarized with respect to each other. The beams are combined and then directed through a polarization filter mounted on the code wheel. The combined beam incurs a phase shift with respect to a reference signal which depends upon the position of the code wheel. The combined polarized beam provides angular position resolution between zero and ninety degrees, but lacks quadrant resolution. Two other light beams are directed to a two channel digital mask pattern imprinted on the code wheel. The mask pattern encodes these latter beams with 'on' or 'off' pulses to provide quadrant resolution. The beams are converted to digital electric signals which are received by a programmable read oly memory PROM. The PROM provides an output corresponding to the angular position of the code wheel to a display. Keywords: Patents. (R.H.)

Descriptors :   *ANGLES, *CODING, *COMPUTER PROGRAMMING, *DIGITAL SYSTEMS, *PATENTS, *POLARIZATION, *SIMULATORS, *SOLID STATE ELECTRONICS, ELECTRIC CHARGE, FILTERS, MASKS, PATTERNS, PHASE SHIFT, POSITION(LOCATION), PULSES, QUADRANTS, READING, RESOLUTION, ROTATION, SIGNALS, WHEELS

Subject Categories : Recording and Playback Devices
      Optics
      Target Direction, Range and Position Finding
      Electrical and Electronic Equipment
      Computer Programming and Software

Distribution Statement : APPROVED FOR PUBLIC RELEASE