EL bar graph for displaying analogue measurements of temperature and the like
US4130776A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 30, 1978 |
| Grant date | Dec 19, 1978 |
| Priority date | — |
| Expiry date | Jan 30, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R13/405
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Each of a row of spaced, parallel, fired-on silver electrodes or bar segments on the face of a substrate has one end thereof disposed in spaced, confronting relation to one edge of an elongate terminal of fired-on silver, which is formed on the face of the substrate parallel to the row of segments. A plurality of wire-sized grids project from said one end of each segment into spaced, parallel, intermeshed relation with a plurality of similar grids which project from the inner edge of the terminal. These spaced sets of grids, there being one such set for each segment, are coated with a photoconductive material to form with the associated set of grids a light-sensitive switch. A first EL lamp overlies the sets of grids or switches with its light-transmitting side facing downwardly; and a second EL lamp overlies the bar segments with its light-transmitting side facing upwardly. Normally when an AC signal is applied across said terminal and the upper electrode on the second lamp, the latter is not illuminated. However, when an analogue ramp voltage, generated in response to a changing parameter such as temperature, pressure, etc., is applied across electrodes of the first lamp at one e…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.