US5160920A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fail safe display for shelf labels
Assignee: International Business Machines Corp
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Filing: 1990-12-07
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Granted: 1992-11-03
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Expires: 2010-12-07
Abstract
Abstract Described is an electronic shelf label LCD device having a segmented liquid crystal (LC) film disposed on a plurality of segmented and non-segmented photovoltaic cells which provide power for driving the LCD device and electrical signals which are used to indicate malfunctioning LCD segments.
Inventors
- 👤 Richard H. Harris
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 07:10
CPC Classifications
G; G06; G06F; G06F11/00; G06F11/07; G06F11/0796; G09; G09G; G09G3/00; G09G3/04; G09G3/16; G09G3/18; G09G2330/00; G09G2330/10; G09G2330/12; Y; Y10; Y10S; Y10S345/00; Y10S345/904
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
131 words
A device for displaying information comprising: a liquid-crystal display (LCD) means, said display means carrying a plurality of display segments which are grouped to form desired shapes and/or alphanumeric characters; a support means coupled to the LCD means, said support means providing photovoltaic conversion from light passing through said LCD means and having a plurality of photovoltaic segments thereon, with said segments being arranged into shapes and/or alphanumeric characters which are similar to those on the LCD means; and control means coupled to the liquid crystal display (LCD) means and the support means; said control means monitoring the support means to detect electrical signals generated as a result of light transmitted through the liquid crystal display means and using said electrical signals to generate error signals representative of malfunctioning display segments.
Claim 2
Independent Claim
131 words
A device for displaying information comprising: a liquid-crystal display (LCD) means, said display means carrying a plurality of display segments which are grouped to form desired shapes and/or alphanumeric characters; a support means coupled to the LCD means, said support means providing photovoltaic conversion from light passing through said LCD means and having a plurality of photovoltaic segments thereon, with said segments being arranged into shapes and/or alphanumeric characters which are similar to those on the LCD means; and control means coupled to the liquid crystal display (LCD) means and the support means; said control means monitoring the support means to detect electrical signals generated as a result of light transmitted through the liquid crystal display means and using said electrical signals to generate error signals representative of malfunctioning display segments.
Claim 3
Dependent Claim
27 words
The device of claim 1 further including a printed circuit board for supporting components of claim 1; said circuit board receiving electrical power from the support means.
Claim 4
Dependent Claim
41 words
The device of claim 2 further including a housing having a back cover and a front cover, with a window section to view the display segment, for encasing the printed circuit board, the support means and the liquid crystal display means.
Claim 5
Dependent Claim
48 words
The device of claim 1 wherein the support means includes a plurality of photovoltaic cells; a plurality of photovoltaic lead, one of each connected to selected ones of the plurality of photovoltaic cells; and a common photovoltaic lead connected to selected ones of the plurality of photovoltaic cells.
Claim 6
Dependent Claim
14 words
The device of claim 1 wherein the liquid-crystal display means includes a liquid-crystal film.
Claim 7
Dependent Claim
17 words
The device of claim 1 wherein the LCD includes a nematic liquid trapped between conductor-carrying support members.
Claim 8
Dependent Claim
77 words
The device of claim 1 wherein the control means includes a controller; a display driver means generating drive signals which energize the display segments in response to control signals outputted by the controller; a first circuit means for generating output signals representative of voltages generated by selected ones of the photovoltaic segments; and a second circuit means for correlating selected ones of the drive signals with selected ones of the output signals to generate the error signals.
Claim 9
Dependent Claim
11 words
The device of claim 7 wherein the controller includes a microprocessor.
Claim 10
Dependent Claim
13 words
The device of claim 7 wherein the first circuit means includes comparator circuits.
Claim 11
Dependent Claim
14 words
The device of claim 7 wherein the second circuit means includes EX OR circuits.
Claim 12
Dependent Claim
156 words
An improved electronic shelf label system comprising: a display subsystem; said display subsystem having a liquid crystal display means on which at least one multisegment alphanumeric character is formed; at least a first photovoltaic cell positioned to receive light transmitted through at least one segment of the multi-segment alphanumeric character and to generate at least a first electrical signal therefrom; at least a second photovoltaic cell positioned to receive light transmitted through non-segmented areas of said display subsystem and to generate and output a second electrical signal representative of said light; a first circuit means for generating and applying electrical drive signals to selected segments of said multi-segment alphanumeric character; a second circuit means for correlating the first electrical signal with the second electrical signal to generate and output a resultant signal; and a third circuit means responsive to the electrical drive signals and the resultant signal to generate an error signal representative of malfunctioning segments.
Claim 13
Dependent Claim
156 words
An improved electronic shelf label system comprising: a display subsystem; said display subsystem having a liquid crystal display means on which at least one multisegment alphanumeric character is formed; at least a first photovoltaic cell positioned to receive light transmitted through at least one segment of the multi-segment alphanumeric character and to generate at least a first electrical signal therefrom; at least a second photovoltaic cell positioned to receive light transmitted through non-segmented areas of said display subsystem and to generate and output a second electrical signal representative of said light; a first circuit means for generating and applying electrical drive signals to selected segments of said multi-segment alphanumeric character; a second circuit means for correlating the first electrical signal with the second electrical signal to generate and output a resultant signal; and a third circuit means responsive to the electrical drive signals and the resultant signal to generate an error signal representative of malfunctioning segments.
Claim 14
Dependent Claim
18 words
The improved electronic shelf label of claim 11 wherein the liquid crystal display means includes liquid crystal film.
Claim 15
Dependent Claim
18 words
The improved electronic shelf label system of claim 12 wherein the first means includes a display driver circuit.
Claim 16
Dependent Claim
18 words
The improved electronic shelf label system of claim 13 wherein the second circuit means includes a comparator circuit.
Claim 17
Dependent Claim
19 words
The improved electronic shelf label system of claim 14 wherein the third circuit means includes an EX OR circuit.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-11-03 | 1996-05-04 | 1996-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-11-03 | 2000-05-04 | 2000-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-11-03 | 2004-05-04 | 2004-11-03 | $7700.00 | Window Closed / Lapsed |