Patent · US Expired

Detection system

US3987413A · kind A · utility

4Cited by
8References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 22, 1975
Grant dateOct 19, 1976
Priority date
Expiry dateJan 22, 1995

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06V30/10
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A character segment detection system adapted for use with conventional scanning apparatus comprising translating apparatus disposed to illuminate an area of a page, detection means disposed for sensing the level of reflected light within a predetermined aperture from the paper and for producing an electrical signal indicative thereof, peak detector means connected to the detection means for producing the output signal indicative of the peak of the electrical signal, differentiator means connected to the detection means for producing an output signal indicative of the first derivative of the electrical signal, rectifying means connected to receive the differentiator means output signal for producing an output signal of only one polarity indicative thereof and comparator means connected to receive the electrical signal and the peak detector means and rectifier means output signals for producing an output signal when the sum of the electrical signal and and the peak detector means signal is greater than the differentiator means output signal.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.