Analogue electrical indicators having a series of electrically-energizable elements
US4232312A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 6, 1978 |
| Grant date | Nov 4, 1980 |
| Priority date | — |
| Expiry date | Mar 6, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R13/406
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An electrical indicator has a consecutive series of light-emitting diodes which are arranged along a straight or curved reference scale. A limited region of the series, comprising several diodes, is energized and this illuminated region is displaced along the scale upon change in an electrical input variable supplied to the indicator such that the position of the region provides an analogue indication of the value of the input variable. To improve the appearance of the display and reduce power consumption, the brightness of the region varies along its length with one or both of the outermost diodes being energized at lower levels than another of the diodes. The indicator may include a shift register having a number of storage locations, each for storing signals representative of a corresponding one of the light-emitting diodes, the signals at these locations being displaced in accordance with change in value of the input variable. Signals output from each storage location of the shift register are supplied to a gate which controls switching of a transistor that is connected in series with a resistor in the energizing circuit of each light-emitting diode. Each energizing circuit inc…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.