Optical member inspecting apparatus
US5835207A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 19, 1996 |
| Grant date | Nov 10, 1998 |
| Priority date | — |
| Expiry date | Sep 19, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/8806
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An optical member inspecting apparatus comprises an illuminating unit for illuminating a target lens to be inspected and a photographing unit to detect the light transmitted through the target lens. The illumination unit has a circular diffuser plate on which a semi-circular light intercepting plate is attached. The diffuser plate can rotate about a rotation axis. The target lens is supported by an X-Y stage that moves the target lens in a plane perpendicular to the rotation axis. An image processing unit detects brightness distributions at different rotational positions of the light intercepting plate to calculate a brightness difference which represents a deviation of the optical axis of the target lens from the rotation axis. The image processing unit controls the X-Y stage based on the brightness difference so as to correct the deviation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.