Contrast indicating arrangement in photoelectric sensing systems
US4644341A · kind A · utility
17Cited by
4References
10Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jul 5, 1984 |
| Grant date | Feb 17, 1987 |
| Priority date | — |
| Expiry date | Jul 5, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R13/405
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A photoelectric sensing system, the adjustment of which is facilitated by the incorporation therein of a contrast indicator with a display in the form of an array of light emitting diodes (LEDs) controlled by a driver circuit which is arranged for successive illumination of the LEDs, preferably on a one-to-one basis. This bargraph type instrument is also effective in photoelectric sensing tasks involving variations of the detected light between "light" and "dark" at a rapid rate, in which case the range of LEDs between these two extremes appears dimly lit at a steady glow.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.