Patent US587493A successfully refreshed from Google Patents.
Patent EP0259875A2 successfully refreshed from Google Patents.
EP0259875A2
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EP
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Active matrix display devices
Assignee: Fujitsu Ltd
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Filing: 1987-09-10
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Granted: —
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Expires: 2007-09-10
Abstract
Abstract An active matrix display device comprising: first and second substrates (10, 9), spaced apart, forming an enclosure with a plurality of display elements (5) arranged in matrix; the first substrate (10) having data bus lines (7) formed on the inside surface thereof, each data bus line (7) having a strip pattern and providing a series of first display electrodes for the display elements; the second substrate (9) having scan bus lines (6), transverse to the data bus lines (7), switch elements (1), and second display electrodes (8) for the display elements, formed on the inside surface thereof; each switch element (1) having a control electrode (2) and two controlled electrodes (3, 4), the control electrode (2) being connected to one scan bus line (6), the first controlled electrode (3) being connected to a second display electrode (8), and the second controlled electrode (4) connected to a scan bus line (6) adjacent the said one scan bus line. An address pulse (e.g. Vg2) applied to a scan bus line (6) has a stepped pulse waveform, which has a first voltage level Vgoff, provided during a period when the scan bus line is not addressed, a second voltage level Vgc, applied in temporal correspondence with addressing of a last precedingly addressed scan bus line, and a third voltage level Vgon for addressing the present scan bus line, wherein the voltage difference between the voltages Vgc and Vgoff is greater than the value of a peak to peak data voltage impressed to said data bus line less switch element threshold voltage.
Inventors
- 👤 Ken-Ichi C/O Fujitsu Limited Pat. Dpt. Oki
- 👤 Satoru C/O Fujitsu Limited Pat. Dpt. Kawai
- 👤 Ken-Ichi C/O Fujitsu Limited Pat. Dpt. Yanai
- 👤 Kazuhiro C/O Fujitsu Limited Pat. Dpt. Takahara
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 13:25
CPC Classifications
G; G09; G09G; G09G3/00; G09G3/20; G09G3/34; G09G3/36; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/136; G02F1/1362; G02F1/1368; G09G3/3611; G09G3/3648; G09G3/3659; G02F2201/00; G02F2201/12; G02F2201/122; G09G2300/00; G09G2300/08; G09G2300/0809; G09G2330/00; G09G2330/08
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
136 words
An active matrix display device comprising: first and second substrates, spaced apart, forming an enclosure with a plurality of display elements arranged in matrix; the first substrate having data bus lines formed on the inside surface thereof, each data bus line having a strip pattern and providing a series of first display electrodes for the display elements; the second substrate having scan bus lines, transverse to the data bus lines, switch elements, and second display electrodes for the display elements, formed on the inside surface thereof; each switch element having a control electrode and two controlled electrodes, the control electrode being connected to one scan bus line, the first controlled electrode being connected to a second display electrode, and the second controlled electrode connected to a scan bus line adjacent the said one scan bus line.
Claim 2
Dependent Claim
136 words
An active matrix display device comprising: first and second substrates, spaced apart, forming an enclosure with a plurality of display elements arranged in matrix; the first substrate having data bus lines formed on the inside surface thereof, each data bus line having a strip pattern and providing a series of first display electrodes for the display elements; the second substrate having scan bus lines, transverse to the data bus lines, switch elements, and second display electrodes for the display elements, formed on the inside surface thereof; each switch element having a control electrode and two controlled electrodes, the control electrode being connected to one scan bus line, the first controlled electrode being connected to a second display electrode, and the second controlled electrode connected to a scan bus line adjacent the said one scan bus line.
Claim 3
Dependent Claim
13 words
A device as claimed in claim 1, wherein the enclosure includes liquid crystal.
Claim 4
Dependent Claim
42 words
A device as claimed in claim 1 or 2, wherein the second substrate further has additional bus lines formed thereon, each parallel and adjacent to a scan bus line, each additional bus line being connected to the relevant adjacent scan bus line.
Claim 5
Dependent Claim
39 words
A device as claimed in claim 3, wherein an insulating layer, for example of silicon oxide or silicon nitride, is formed on each additional bus line and the relevant adjacent scan bus line is formed on the insulating layer.
Claim 6
Dependent Claim
28 words
A device as claimed in claim 4, wherein the additional bus line is connected to the relevant adjacent scan bus line on a peripheral region of the substrate.
Claim 7
Dependent Claim
35 words
A device as claimed in claim 3 or 4, wherein each additional bus line has at least one connection to the relevant adjacent scan bus line for each display element along that scan bus line.
Claim 8
Independent Claim
42 words
A device as claimed in any preceding claim, wherein the connection of the second controlled electrode of each switch element to a scan bus line is by way of a film resistor, made of high sheet resistivity material, for example tin oxide.
Claim 9
Dependent Claim
28 words
A device as claimed in claim 7, wherein each film resistor has a resistance more than ten times that of the total length of a scan bus line.
Claim 10
Independent Claim
42 words
A device as claimed in any preceding claim, wherein the switch elements are thin film transistors, each having a gate electrode as the control electrode, a source electrode as the first controlled electrode, and a drain electrode as the second controlled electrode.
Claim 11
Independent Claim
53 words
A device as claimed in any preceding claim, wherein the first and second display electrodes of the display elements, and connecting lines between first controlled electrodes and second display electrode and between second controlled electrodes and scan bus lines, are thin films of transparent and electrically conductive material, for example indium tin oxide.
Claim 12
Independent Claim
21 words
A device as claimed in any preceding claim, wherein the scan bus lines are of metal layer, for example aluminum layer.
Claim 13
Independent Claim
50 words
A device as claimed in any preceding claim, wherein a pair of switch elements are provided in respect of each display element, on the second substrate, the control electrodes of the pair of switch elements being connected in common to the relevant said one scan bus line through a resistor.
Claim 14
Independent Claim
114 words
A method of driving a device as claimed in any preceding claim, comprising applying an address pulse to a scan bus line, the address pulse having a stepped pulse waveform, which has a first voltage level Vgoff, provided during a period when the scan bus line is not addressed, a second voltage level Vgc, applied in temporal correspondence with addressing of a last precedingly addressed scan bus line, and a third voltage level Vgon for addressing the present scan bus line, wherein the voltage difference between the voltages Vgc and Vgoff is greater than the value of a peak to peak data voltage impressed to said data bus line less switch element threshold voltage.
Claim 15
Dependent Claim
32 words
A method as claimed in claim 13, further comprising application of data voltage pulses which maintain the same polarity during each frame period, with polarity reversed from one frame to the next.
Claim 16
Dependent Claim
42 words
A method as claimed in claim 13, comprising an application of data voltage pulses, which reverse polarity for each successively addressed scan bus line in a frame, and reverse polarity, as applied to the same scan bus line, from frame to frame.
Claim 17
Dependent Claim
50 words
A method as claimed in claim 13, 14 or 15, wherein the second voltage level Vgc of an address pulse which is selected as an intermediate voltage value between respective voltage levels at which an addressed display is driven to a display saturation level and to a display threshold level.
References Cited (Backward Citations)
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