Apparatus and method for measuring color of a measurement object
US5963334A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 4, 1998 |
| Grant date | Oct 5, 1999 |
| Priority date | — |
| Expiry date | Mar 4, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/255
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A color measuring apparatus is provided with a radial illumination unit for projecting illumination light to a measurement object at a first illumination angle in a plurality of directions, a unidirectional illumination unit for projecting illumination light to the measurement object at a second illumination angle in a single direction, a unidirectional light receiving unit for receiving a light ray reflected at a first angle .theta.1 from the direction of regular reflection out of illumination light projected from the radial illumination unit and reflected by the measurement object, and a light ray reflected at a second angle .theta.2 from the direction of regular reflection out of illumination light projected from the unidirectional illumination unit and reflected by the measurement object, the second angle .theta.2 being larger than the first angle .theta.1, and a processing unit for calculating a color value at the first angle .theta.1 and a color value at the second angle .theta.2 based on an output of the unidirectional light receiving unit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.