Method and apparatus for sensing color of articles
US5493404A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 7, 1993 |
| Grant date | Feb 20, 1996 |
| Priority date | — |
| Expiry date | Jun 7, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J3/513
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Method and apparatus for sensing the color of articles wherein a first pair of wavelengths is selected on a plurality of light reflection curves in terms of reflected light wavelength spectrum, these curves being associated with a plurality of articles constituting a sample representative of the color range to be sensed. The first pair of wavelengths delimits a first range of wavelengths corresponding to light reflection values in these curves, the light reflection values in each of the curves being in a substantially linear relationship over said first range of wavelengths. Each article to be inspected is illuminated with light comprising the first pair of wavelengths, and the light reflected therefrom is measured to detect light reflection values corresponding to the first pair of wavelengths. A primary signal is produced which represents a resulting difference between said detected light reflection values, this signal being indicative of the color of the inspected article.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.