Inspection apparatus employing a circular scan
US4099051A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 18, 1976 |
| Grant date | Jul 4, 1978 |
| Priority date | — |
| Expiry date | Nov 18, 1996 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/952
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The disclosure is directed to an apparatus for inspecting the surface of an object at an inspection position. In accordance with an embodiment of the invention, source means are provided for generating a relatively narrow collimated beam of radiation, the source preferably, but not necessarily, being a laser. A scanning means, spaced from the inspection position, is provided for effecting a substantially circularly shaped scan of the laser beam at the inspection position. The scanning means may typically comprise a tilted rotatable mirror which is rotated at the scan rate. A reflector means is disposed between the scanning means and the inspection position. The reflector means, typcially a mirror, has an aperture therein to allow passage of the scanning beam travelling toward the inspection position. The mirror reflective surface is oriented angularly with respect to the axis of the scan so that radiation received from the object is reflected toward an off-axis region. Photodetector means are located at the off-axis region, and a lens means, disposed between the reflector means and the photodetector, serves to focus radiation from the reflector means onto the photodetector. In a pr…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.