Flicker photometer
US5936724A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 11, 1998 |
| Grant date | Aug 10, 1999 |
| Priority date | — |
| Expiry date | Mar 11, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J1/34
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A flicker photometer has beam generating means (1, 8 and 4) for generating two beams of light of different colors. Light from the beams is viewed at the viewing means, and the intensity of light of one beam relative to that of the other beam can be adjusted by adjustment means comprising an attenuating filter (20) which is movably mounted in the path of one beam. Movement of the filter relative to the beam alters the degree to which the beam is attenuated, and is achieved using an electric motor (22). The motor provides a relatively easy means of adjusting the filter position, and can be used to provide coarse and fine adjustments in response to suitable signals from an optical encoder. The motor also enables the filter, along with the beam generating means, to be mounted on a movable table for use in enabling the photometer to accommodate both short and long-sighted subjects.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.