Patent · US Expired

Image input method and apparatus

US5781312A · kind A · utility

36Cited by
4References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 11, 1995
Grant dateJul 14, 1998
Priority date
Expiry dateDec 11, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N25/63
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An image input apparatus capable of reliably reducing random noise and switching noise arising during a dummy pixel period using a simple circuit configuration and providing a high-quality video signal without horizontal lines. The image input apparatus is provided with a clamping circuit made up of a capacitor for feeding an analog image signal supplied from a CCD solid-state image pickup element via a first amplifier to a second amplifier through an alternating-current link, a reference voltage source for generating a predetermined reference voltage VR, and a first switch for effecting switching during the dummy pixel period of the CCD solid-state image pickup element. The clamping circuit is further provided with a resistor disposed between the capacitor and the second amplifier, and a second switch for selectively bridging across the resistor 152. This second switch is complimentarily activated in relation to the operation of the first switch.

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