COLORIMETER, COLORIMETER SENSOR UNIT AND COLOUR DETERMINATION PROCESS

摘要

A hand-held colorimeter (101) suitable for use by blind or colour-blind individuals to determine the colour of a surface, for example of a fabric, has an aperture (110) which, in use, is covered by the surface (113) whose colour is to be determined. Three LEDs (115, 116, 117) emitting orange, green, and blue light illuminate the surface and diffuse reflections therefrom containing orange, green, and blue spectrum sample values are used to determine the luminous reflectivity and chromaticity values for the colour of the surface. The measured values are compared with colorimetric values of reference surfaces and the best fit used to determine the reference surface whose colour is closest to the colour of the surface. The colorimeter may output the name of the colour aurally.