×

Method for optical code pattern enhancement and generation

  • US 4,970,380 A
  • Filed: 09/08/1989
  • Issued: 11/13/1990
  • Est. Priority Date: 09/08/1989
  • Status: Expired due to Fees
First Claim
Patent Images

1. A method of making a position sensor, the sensor including a movable encoder having a track extending along a dimension of the encoder, the track having an optical property that varies with position along said dimension, the sensor further including means for directing an optical input beam onto the track at a selected position along said dimension such that the encoder responds to the input beam by producing a modulated beam having an intensity that is a function of the optical property at the selected position, whereby the intensity of the modulated beam encodes the position of the encoder along said dimension, the method comprising:

  • (a) determining the intensity of the modulated beam with the encoder at the selected position, and producing a corresponding measurement signal;

    (b) comparing said measurement signal to a predetermined target value for the selected position;

    (c) if the difference between the measurement signal and the target value exceeds a predetermined tolerance, modifying the optical property at said position; and

    (d) repeating steps (a)-(c) until said difference is within said tolerance.

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