| (19) |
 |
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(11) |
EP 0 447 919 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
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08.01.1992 Bulletin 1992/02 |
| (43) |
Date of publication A2: |
|
25.09.1991 Bulletin 1991/39 |
| (22) |
Date of filing: 12.03.1991 |
|
| (51) |
International Patent Classification (IPC)5: G09G 3/36 |
|
| (84) |
Designated Contracting States: |
|
DE FR GB IT NL |
| (30) |
Priority: |
13.03.1990 JP 61934/90
|
| (71) |
Applicant: Stanley Electric Co., Ltd. |
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Meguro-ku
Tokyo 153 (JP) |
|
| (72) |
Inventor: |
|
- Clerc, Jean-Frederic
Yokohama-shi,
Kanagawa-ken (JP)
|
| (74) |
Representative: Geyer, Ulrich F., Dr. Dipl.-Phys. et al |
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WAGNER & GEYER,
Patentanwälte,
Gewürzmühlstrasse 5
80538 München
80538 München (DE) |
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| |
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| (54) |
Drive circuit for dot matrix display |
(57) A drive circuit for a dot matrix liquid crystal display which receives polarity changing
drive voltages in different fields, comprising segment drivers for supplying low voltage
picture signals and common drivers for supplying a first voltage having a large voltage
difference from the picture signal during a selected time and a second voltage having
a small voltage difference from the picture signal during non-selected time.