US3877017A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of driving liquid crystal display device for numeric display
Assignee: Hitachi Ltd
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Filing: 1974-02-11
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Granted: 1975-04-08
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Expires: 1994-02-11
Abstract
Abstract A method of driving in time division fashion a liquid crystal display device for numeric display having a plurality of sets of segment electrodes for one digit and a plurality of separated light electrodes disposed opposite to the plurality of segment electrode sets respectively, the corresponding segment electrodes of the respective digits being commonly interconnected, wherein the highest voltage V.sub.0 applied to the segment and digit electrodes is divided into three voltage levels V.sub.0, V.sub.1 and V.sub.2 (V.sub.0 > V.sub.1 > V.sub.2 > 0), and these voltages are suitably combined to apply to a desired display point a voltage of .+-. V.sub.0 in its selected state and a voltage of about .+-. 1/3 V.sub.0 in its half-selected and its non-selected state so that the device can be driven in time division fashion by a low voltage.
Inventors
- 👤 Hideaki Kawakami
- 👤 Yutaka Yoneda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:00
CPC Classifications
G; G04; G04G; G04G9/00; G04G9/08; G04G9/12; G04G9/122; G04G9/0023; G04G9/0029; G04G9/0047; G09; G09G; G09G3/00; G09G3/04; G09G3/16; G09G3/18
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
124 words
A method of driving in time division fashion a liquid crystal display device for numeric display having a plurality of sets of segment electrodes for one digit and a plurality of separated digit electrodes disposed opposite to the plurality of segment electrode sets respectively, the corresponding segment electrodes of the respective digits being commonly interconnected, comprising the steps of dividing the highest voltage V.sub.0 applied to said segment and digit electrodes into three voltage levels V.sub.0, V.sub.1 and V.sub.2 (V.sub.0 > V.sub.1 > V.sub.2 > 0), and suitably combining the divided voltages to apply to a desired display point a voltage of .+-. V.sub.0 in its selected state and a voltage of about .+-. 1/3 V.sub.0 in its halfselected state and its non-selected state.
Claim 2
Independent Claim
124 words
A method of driving in time division fashion a liquid crystal display device for numeric display having a plurality of sets of segment electrodes for one digit and a plurality of separated digit electrodes disposed opposite to the plurality of segment electrode sets respectively, the corresponding segment electrodes of the respective digits being commonly interconnected, comprising the steps of dividing the highest voltage V.sub.0 applied to said segment and digit electrodes into three voltage levels V.sub.0, V.sub.1 and V.sub.2 (V.sub.0 > V.sub.1 > V.sub.2 > 0), and suitably combining the divided voltages to apply to a desired display point a voltage of .+-. V.sub.0 in its selected state and a voltage of about .+-. 1/3 V.sub.0 in its halfselected state and its non-selected state.
Claim 3
Dependent Claim
79 words
A method as claimed in claim 1, wherein the voltage V.sub.0 and then ground potential is applied to the segment electrode in the selected state, and the voltage V.sub.2 and then voltage V.sub.1 is applied to the segment electrode in the non-selected state, while the ground potential and then voltage V.sub.0 is applied to the digit electrode in the selected state, and the voltage V.sub.1 and then voltage V.sub.2 is applied to the digit electrode in the non-selected state.
Claim 4
Dependent Claim
109 words
A method as claimed in claim 1, wherein a first display period includes application of the voltages V.sub.0 and V.sub.2 to the segment electrode in the selected state and non-selected state respectively and application of the ground potential and voltage V.sub.1 to the digit electrode in the selected state and non-selected state respectively, and a second display period includes application of the ground potential and voltage V.sub.1 to the segment electrode in the selected state and non-selected state respectively and application of the voltages V.sub.0 and V.sub.2 to the digit electrode in the selected state and non-selected state respectively, said first and second display periods being then sequentially repeated.
Claim 5
Dependent Claim
66 words
A method as claimed in claim 1, wherein the liquid crystal display device includes three switching means for dividing the voltage V.sub.0 and logic means for selectively turning on and off said switching means, and wherein the combination of an address signal and clock signal applied to the logic means is utilized to selectively turn on and off the switching means for obtaining a desired voltage.
Claim 6
Dependent Claim
34 words
A method as claimed in claim 4, wherein two clock signals of opposite phase are applied to the logic means to obtain the respective voltages applied to the segment electrode and the digit electrode.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-07 | 1978-10-07 | 1979-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-07 | 1982-10-07 | 1983-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-07 | 1986-10-07 | 1987-04-08 | $7700.00 | Window Closed / Lapsed |