Vehicle display device
US5815072A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 9, 1997 |
| Grant date | Sep 29, 1998 |
| Priority date | — |
| Expiry date | Jul 9, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01P1/08
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A vehicle display device such as a speed meter including indicators, many segments illuminated in two or more colors by plural LEDs and an indicator control circuit. The indicators dispose the segments so as to display a variable such as a car speed in a bar graph or in the form of a number. The indicator control circuit displays the variable by controlling the lighting of the LEDs and changes an emitted light color of indication based on a fixed color changing reference value in accordance with a value of the variable. The control circuit controls a duty ratio of a supply current or a current value in a predetermined set value range determined on the basis of the color changing reference value. Namely, brightness of the emitted light color before a color change is gradually decreased, while brightness of the emitted light color after the color change is gradually increased.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.