Patent · US Expired

Lighting apparatus and color measuring apparatus using the same

US5004349A · kind A · utility

18Cited by
3References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 4, 1989
Grant dateApr 2, 1991
Priority date
Expiry dateApr 4, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N21/255
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A color measuring apparatus for measuring the color of a sample has a light source measuring section for detecting color temperature of light coming from a light source without passing through or being reflected by the sample. Relationship between a plurality of color temperatures and a plurality of emission time periods of the light source is stored in a memory. A microcomputer compares each of detected color temperatures with a predetermined value and determines a certain time period on the basis of both the relationship stored in the memory and a comparison result. A lighting circuit energizes the light source during the time period determined by the computer so that the light source keeps lighting the sample. A sample measuring section detects light coming from the sample and the microcomputer measures a color of the sample.

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