×

Electronic camera-processing circuit for automatically tracking particles which move across an optical image

  • US 4,928,176 A
  • Filed: 04/07/1988
  • Issued: 05/22/1990
  • Est. Priority Date: 04/08/1987
  • Status: Expired due to Fees
First Claim
Patent Images

1. The method of automatically tracking a single selected particle moving across an image field as a signal dot, and determining the velocity of said selected particle, comprising the steps of:

  • (a) scanning said image field in horizontal and vertical directions to generate an electrical output signal defining said particle, said output signal being synchronized with the scanning of each dot in said image field;

    (b) generating horizontal and vertical counts corresponding respectively to the horizontal and vertical coordinates of said particle;

    (c) generating start and end horizontal electronic mask aperture coordinate counts by adding and subtracting respectively first predetermined quantities to said horizontal counts, and storing said horizontal coordinate counts;

    (d) generating start and end vertical electronic mask aperture coordinate counts by adding and subtracting respectively second predetermined quantities to said vertical counts, and storing said vertical coordinate counts;

    (e) comparing said horizontal coordinate counts with said horizontal counts, and generating a horizontal aperture signal when said horizontal count coincides with said start or end horizontal electronic mask aperture coordinate count;

    (f) comparing said vertical coordinate counts with said vertical counts, and generating a vertical aperture signal when said vertical count coincides with said start or end vertical electronic mask aperture coordinate count;

    (g) generating an electronic mask aperture signal from said horizontal and vertical aperture signals when said scanning step (a) occurs within an electronic mask defined by said horizontal and vertical electronic mask aperture coordinate counts;

    (h) storing said horizontal and vertical counts when the single selected particle in said electrical output signal is within said electronic mask;

    (i) repeating said steps (c) to (h) to redefine after each vertical scan said electronic mask aperture for the next scanned image field, the mask aperture for each vertical scan being determined by the position of said particle during the previous scan; and

    (j) determining the velocity of said particle from the change in position thereof in successive scans.

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