×

Method for controlling at least one light barrier, control circuit and thus equipped self-service terminal

  • US 10,104,736 B2
  • Filed: 02/23/2016
  • Issued: 10/16/2018
  • Est. Priority Date: 02/26/2015
  • Status: Active Grant
First Claim
Patent Images

1. A method for controlling at least one light barrier, the method comprising the steps of:

  • initially adjusting a lower threshold and an upper threshold based on a predetermined minimum reception level so that each of the lower and upper thresholds is a fraction of the predetermined minimum reception level;

    emitting light from an optical transmitter to an optical receiver;

    determining a current reception level based on light received by the optical receiver;

    checking whether the current reception level falls below the lower threshold or exceeds the upper threshold to determine whether the light barrier is interrupted;

    defining an allowable reception level range between the minimum reception level and a predetermined saturation reception level; and

    checking whether the current reception level is outside an allowable reception level range;

    when the current reception level is outside the allowable reception level range, calibrating at least a first parameter for the operation of the optical transmitter based on the minimum reception level and/or the saturation reception level;

    when the current reception level is above the predetermined saturation reception level, reducing the first parameter successively until the current reception level at the optical receiver is below the predetermined saturation reception level;

    wherein the step of calibrating at least the first parameter comprises the step of calibrating an operating current for the operation of the optical transmitter based on the minimum reception level and/or the predetermined saturation reception level; and

    wherein the step of calibrating the operating current further comprises the step of calculating a gradient of one characteristic curve of the light barrier and readjusting the first parameter to a target value that is calculated based on the gradient.

View all claims
  • 10 Assignments
Timeline View
Assignment View
    ×
    ×