Optical scanner calibration device
US6075613A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 26, 1999 |
| Grant date | Jun 13, 2000 |
| Priority date | — |
| Expiry date | Feb 26, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/4785
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An optical scanning system includes a power meter that during calibration operations is illuminated by an attenuated excitation beam. The power meter measures optical power in the attenuated excitation beam at various index settings of a variable optical attenuator, and the system constructs a lookup table that relates incident excitation beam power to the index settings of the attenuator. The system then uses the table to select the appropriate setting for the attenuator in order to deliver to the sample an excitation beam of a specified optical power. The system calibrates the gain of a detector by redirecting, or reflecting, the excitation beam of known intensity to the detector. A photometric device in the detector produces a signal that is proportional to the intensity of the beam at various gain settings. The system then produces a lookup table that relates the gain settings to the actual gain of the detector, that is, to the ratio of the known incident power to the detector readings. The system thereafter uses the table to select the appropriate gain setting for data collection and/or to normalize the data. A beam splitter included in the system preferably discriminates betw…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.