Patent · US Expired

Signal processor circuit for endoscope systems of all-pixels readout type

US5929900A · kind A · utility

67Cited by
3References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 15, 1997
Grant dateJul 27, 1999
Priority date
Expiry dateOct 15, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N23/555
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A signal processor circuit which stabilizes a clamp processing of black levels even in an endoscope system of an all-pixels readout type and prevents image qualities from being degraded at a stage to shift from a still image to a moving image in particular. In this signal processor circuit, video signals of all picture elements obtained with a single exposure are read out of a CCD, odd line data is stored into a first memory, even line data is stored into a second memory, and mixed picture element signals are generated by a mixer circuit, whereafter a predetermined image processing is performed by a first DVP. A clamp circuit and an A/D converter are disposed at stages preceding the first and second memories, a through video signal output from the A/D converter is input into the first DVP by way of a selector circuit on the basis of an optical black pulse and a black level clamp signal generated on the basis of the through video signal is fed back to the clamp circuit. Accordingly, the signal processor circuit can perform a favorable clamp processing without using past data stored in the memories.

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