×

Rotary encoder and input device using the same

  • US 5,644,127 A
  • Filed: 12/22/1994
  • Issued: 07/01/1997
  • Est. Priority Date: 12/27/1993
  • Status: Expired due to Term
First Claim
Patent Images

1. A rotary encoder comprising:

  • a light receiving unit including a first light receiving element and a second light receiving element which receive light emitted from a light emitting element via slits formed at a rotary disk and respectively generate detection signals whose phases differ from each other substantially by 90°

    ;

    a first waveform shaping circuit which compares the detection signal from said first light receiving element with a reference value and generates a first detection output of a rectangular waveform;

    a second waveform shaping circuit which compares the detection signal from said second light receiving element with the reference value and generates a second detection output of a rectangular waveform;

    a peak hold circuit which receives the detection signal from said first light receiving element and holds the peak value thereof; and

    a reference value generating circuit which generates the reference value depending on the peak value held at said peak hold circuit.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×