Position tracking system using a radiation director which directs radiation from a radiation source onto a radiation sensor, depending on the position of the radiation source
US5521373A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 6, 1993 |
| Grant date | May 28, 1996 |
| Priority date | — |
| Expiry date | Oct 6, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S3/043
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A radiation source directs radiation toward a radiation sensor in such a way that the intensity of radiation sensed by the radiation sensor alternates in a periodic manner as the radiation source moves radially relative to the radiation sensor. The radiation sensor generates either a "1" or a "0" depending upon whether the intensity of the radiation sensed by the radiation sensor is above or below a particular reference value. Thus, the angular position of the radiation source relative to the radiation sensor is indicated by an alternating series of "1"s and "0"s. A multi-bit binary value which indicates the absolute position of the radiation source relative to the radiation sensor can be generated. In this case, a band of radiation is directed toward the radiation sensor. The radiation band is separated into a plurality of portions, the intensity of each successive portion being twice the frequency of the preceding portion. Each portion of the radiation band impinges upon a corresponding sensor. The signal generated by each sensor element is thus one bit of a multi-bit binary value which varies as the radiation source moves radially relative to the radiation sensor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.