Patent · US Expired

Control apparatus capable of improving a rise time characteristic of a light source

US6313586A · kind A · utility

18Cited by
3References
5Claims
0Family size

Assignees

Inventors

Key dates

Filing dateMar 30, 2000
Grant dateNov 6, 2001
Priority date
Expiry dateMar 30, 2020

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05B41/386
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An image input apparatus comprises a cold cathode tube light source and a solid imaging device. The image input apparatus reads an image from a document paper by receiving at the solid imaging device a reflected light which is obtained by reflecting a light of the cold cathode tube light source on the document paper. On putting cold cathode tube light source into an on-state, an inverter control circuit controls an inverter to make the inverter supply the cold cathode tube light source with an overcurrent higher than a predetermined tube current which is for use in continuously and stably irradiating a predetermined luminous energy from the cold cathode tube light source. After the overcurrent is applied to the cold cathode tube light source during a predetermined duration, the inverter control circuit controls the inverter to make the inverter reduce the overcurrent to a predetermined current in accordance with an output of the solid imaging device.

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