Method for calibrating a reflectometer containing black and white references displaced from the sample position
US4566798A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 10, 1983 |
| Grant date | Jan 28, 1986 |
| Priority date | — |
| Expiry date | Nov 10, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/474
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method is disclosed for calibrating a reflectometer using black and white references observed in locations optically different from the sample location. Dark and light standards are selected to have reflectance values, while examined in the detection location of the test elements, that are within .+-.0.005 and .+-.0.05 of the values of the black and white references, respectively, when examined in a location displaced from the detection location of the test elements. Such standards are then read on a referee reflectometer having "ideal" black and white references, and the reflectances so read on the referee reflectometer are recorded for use as calibrating factors in making reflectance readings for the test elements.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.