Patent · US Expired

Image processing device for producing a variable period pulse-width modulated binary image signal

US5784495A · kind A · utility

0Cited by
6References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 29, 1995
Grant dateJul 21, 1998
Priority date
Expiry dateJun 29, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N1/40037
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A period determination signal is generated in accordance with the image type of an input image signal. A clock signal having one of a plurality of periods is generated in accordance with the period determination signal. A CR integration circuit having a resistor and at least one capacitor generates a triangular-wave signal based on the clock signal. The combined capacitance of the CR integration circuit is changed in accordance with the period determination signal. A pulse-width modulated binary image signal is produced by comparing the triangular-wave signal with the input image signal. The amplitude of the triangular signal is kept constant by changing the combined capacitance of the CR integration circuit in proportion to the period of the clock signal.

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