Patent · US Expired

Darkroom illumination equipment

US6142647A · kind A · utility

14Cited by
7References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 15, 1997
Grant dateNov 7, 2000
Priority date
Expiry dateJul 15, 2017

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S362/80
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A casing of darkroom illumination equipment is composed of a base assembly and a lid. A substrate mounting light emitting diodes, a milky colored plate, a filter and a transparent plate are placed in the casing. The light emitting diode which emits the light for which spectrum has its peak at the wavelength of 585 nm is used so as not to affect photographic color paper. The filter eliminates the light having wavelengths in the lower slope apart from the peak in the spectrum and allows only the light having the wavelengths at the peak and in the proximity of the peak to pass through.

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