Photometric device
US12392659B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 4, 2021 |
| Grant date | Aug 19, 2025 |
| Priority date | — |
| Expiry date | Apr 29, 2042 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J3/18
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The photometric device includes a variable light attenuator. The variable light attenuator includes a plurality of light attenuation filters and a driving device. Each of the plurality of light attenuation filters includes an interference multilayer film and a transparent substrate. A combination of any two of the plurality of light attenuation filters is set as a first light attenuation filter and a second light attenuation filter. A first optical path length of the first transparent substrate of the first light attenuation filter is different from a second optical path length of the second transparent substrate of the second light attenuation filter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.