Automatic spectrophotometer calibration system
US5251006A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 7, 1991 |
| Grant date | Oct 5, 1993 |
| Priority date | — |
| Expiry date | Mar 7, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2201/1283
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In a spectrophotometer having an oscillating grating, an automatic calibration system is provided to ensure that the instrument constants are recomputed before each measurement of an unknown sample. In the system, whenever a reference scan is carried out, a second scan through an absorbance standard is carried out automatically and the data obtained is used to correct the instrument coefficients relating the angular position of the grating to the wavelength. The corrected coefficients are then stored to be used in the measurement of the unknown sample immediately thereafter. For near infrared spectrum measurements, the absorbance standard is a polystyrene plate. For visual measurements, the absorbance standard is a didymium plate. The didymium plate is mounted on the polystyrene plates eclipse a portion of the polystyrene plate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.