Optical sensor for servo position control
US4570191A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 20, 1984 |
| Grant date | Feb 11, 1986 |
| Priority date | — |
| Expiry date | Jul 20, 2004 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01J21/08
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
This optical sensor has cylindrical symmetry and is comprised of a semiconductor light source/light detector combination and an optical element comprising a single lens, where the sensor is particularly suitable for uses in accurate position detection in data recording systems. In a preferred embodiment, the light source is a forward-biased p-n junction, while the light detector is a reverse-biased p-n junction located below the light source and coaxial therewith. Light from the source is directed to a point on a data recording medium and the light reflected therefrom passes through the light source to the light detecting junction. The ac signal corresponding to the reflected light is an indication of the position of the recording head with respect to the data storage medium.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.