Optical scanning method with circular arc scanning traces
US5216247A · kind A · utility
Inventors
Key dates
| Filing date | Feb 7, 1992 |
| Grant date | Jun 1, 1993 |
| Priority date | — |
| Expiry date | Feb 7, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70216
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical scanning method is described in which a device essentially comprises a rotational optical system S and a working plane W fed in a predetermined direction. The optical system forms the image of a stationary point A at point B on the working plane W. The image point is scanned along a circular are by rotating the optical system around the rotational axis. In a preferred device, point A lies approximately on the rotational axis and point B lies off the rotational axis. And the circular arc generated by the scanning of point B is in the working plane approximately perpendicular to the rotational axis. A 2-dimensional scanning is completed by the rotation of the optical system around the rotational axis and the translation of the working plane in a predetermined direction, which is synchronized with the rotation of the optical system. When the radiation beam E propagates from point A to B, the device is for information writing in (e.g. lithography) and the working plane is a recording medium. When the radiation beam E propagates from the working plane to point A, the device is for information reading-out or pattern acquisition, in which a point detector is positioned right be…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.