Device for determining position and movement of scanning laser beam
US6995357B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 23, 2002 |
| Grant date | Feb 7, 2006 |
| Priority date | — |
| Expiry date | Mar 1, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/1821
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An improved method and apparatus for controlling a scanning laser are provided by the present invention. In accordance with a preferred embodiment, a single feedback sensor is placed along the scan path of a scanning laser such that it senses the laser twice during each scan. The time intervals between the sensor sensing the laser are measured and examined to determine the position and direction of the scanning laser. These time intervals may also be used to ensure that the scanning device is operating at its resonant frequency. In systems that require detecting the laser as it enters and leaves the imaging window, a reflective device is used to create a beam path from the edge of the imaging window back to the single feedback sensor such that the sensor detects the laser four times during each scan. In such an embodiment, the drive signal used to scan the laser along its scan path can be compared to the pulses received from the sensor to determine whether or not a detected time interval corresponds to a particular physical portion of the scan path.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.