Computer graphics processing and selective visual display system – Plural physical display element control system – Segmented display elements
Patent
1997-03-12
1998-09-22
Saras, Steven J.
Computer graphics processing and selective visual display system
Plural physical display element control system
Segmented display elements
345 46, 345117, G06F 314
Patent
active
058121021
ABSTRACT:
A system and method of monitoring light emitted from a light emitting diode (LED) display device, which typically has a plurality of selectively energizable display segments which are grouped to form desired shapes and/or alphanumeric characters, is provided, particularly for use in an Aspect Display Unit (ADU) that requires vitality when utilized in the railroad industry as a component of an Automatic Train Protection system utilized in the railroad industry. In a preferred embodiment, each particular segment of the LED display device is independently monitored by an accompanying independent dual photo-transistor circuit when a non-vital output periodically drives each segment to a known electrical state and then back to the original state. A first and a second photo-transistor is used for each segment of the LED display. Each segment and the accompanying first and second phototransistor is surrounded by a shield which prevents light from other segments from being detected by the particular first and second photo-transistor. The first photo-transistor is directed toward the particular segment to sense light emitted therefrom and ambient light thereabout, while the second photo-transistor is directed away from the particular segment sense only ambient light thereabout that segment. The first and second photo-transistors generate electrical signals which are representative of the light detected by each of the first and second photo-transistors. The generated electrical signals drive a monitoring circuit which generates error signals representative of malfunctioning LED display segments, based on a comparison to a fixed voltage of a difference in voltages provided from the first and second photo-transistors.
REFERENCES:
patent: 3573814 (1971-04-01), Lang
patent: 3790946 (1974-02-01), Hendricks
patent: 4095217 (1978-06-01), Tani et al.
patent: 4242677 (1980-12-01), Jonath
patent: 4247852 (1981-01-01), Utzinger
patent: 4297692 (1981-10-01), Maier
patent: 4311993 (1982-01-01), Strobel
patent: 4408869 (1983-10-01), Tomosada et al.
patent: 4420748 (1983-12-01), Jurgen
patent: 4541066 (1985-09-01), Lewandowski
patent: 4592003 (1986-05-01), Kobayashi et al.
patent: 4644341 (1987-02-01), Warner
patent: 4734688 (1988-03-01), Adams
patent: 4847606 (1989-07-01), Beiswenger
patent: 4951037 (1990-08-01), Goossen
patent: 5160920 (1992-11-01), Harris
patent: 5406301 (1995-04-01), Ravid
patent: 5446564 (1995-08-01), Mawatari et al.
patent: 5515390 (1996-05-01), Benton
Cichowski David E.
Sprole, Jr. Bernard J.
Kovalick Vincent E.
Saras Steven J.
Sembrat Kevin A.
Union Switch & Signal Inc.
LandOfFree
Vital monitoring system for seven-segment display used in railro does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Vital monitoring system for seven-segment display used in railro, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Vital monitoring system for seven-segment display used in railro will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1626576