Optical encoding that utilizes total internal reflection
US7145127B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 25, 2004 |
| Grant date | Dec 5, 2006 |
| Priority date | — |
| Expiry date | Jan 5, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/34707
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A coding element such as a codewheel includes first and second surfaces that are configured with respect to each other and with respect to a light beam such that the light beam is reflected at the two surfaces using the optical phenomenon of total internal reflection. The coding element also includes a coding pattern that is aligned in an optical path of the light beam after the light beam has reflected off of both of the surfaces. A coding element with surfaces that reflect a light beam as a result of total internal reflection can be utilized in an encoding system that operates in transmission while the light source and the photodetector array are located on the same side of the coding element.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.