Method and apparatus for indicating angular displacement
US4032158A · kind A · utility
4Cited by
6References
3Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 3, 1975 |
| Grant date | Jun 28, 1977 |
| Priority date | — |
| Expiry date | Sep 3, 1995 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B11/272
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A tone arm for a record player having a mirror at one end is provided. Opposite the mirror are a light source and two detector elements. When the tone are pivots from a desired angle light from the source is reflected upon the element more than on the other. The mirror is convexly curved so that pivotal motions of the tone arm in one plane will not affect the amount of light reaching the detectors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.