Light detector particularly adapted for detecting the position of edges of moving strip
US4157477A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 11, 1977 |
| Grant date | Jun 5, 1979 |
| Priority date | — |
| Expiry date | Oct 11, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/342
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A detector for detecting the position of the edges of a moving strip which produces an electrical signal proportional to the transverse position of the strip. A light source shines on the edge of the strip. A smooth surfaced sheet of translucent plastic material containing a fluorescent pigment is placed below the edge and opposite the light source. The pigment in the portion of the sheet of the strip and exposed to the light source outside the edge fluoresces producing light energy in amounts proportional to the area of the sheet exposed to the light source. This light energy travels between the sheet surfaces to the edges of the sheet. Photoelectric sensitive means are operatively associated with the edges of the sheet for producing an electrical signal proportional to the amount of fluorescent generated light energy which signal can be amplified to control power means for respositioning the strip.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.