US3786486A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multiplex driving circuit
Assignee: Olivetti SpA
•
Filing: 1971-08-11
•
Granted: 1974-01-15
•
Expires: 1991-08-11
Abstract
Abstract A multiplex circuit for driving a multicharacter liquid crystal display, each character having a segmented and a common electrode, which selectively applies an actuating voltage to selected segmented electrodes of all the characters in parallel while applying an AC erasing voltage to the common electrodes of all the nonselected characters. The common electrode of the selected character is set to a reference potential.
Inventors
- 👤 V Torresi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:11
CPC Classifications
G; G09; G09G; G09G3/00; G09G3/04; G09G3/16; G09G3/18; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1339; G02F1/13392
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
90 words
A multiplex driving circuit for a multicharacter liquid crystal display, each of said characters including a plurality of individually actuable electrodes and a common electrode comprising: sequential means for sequentially connecting a reference potential to the common electrode of successive ones of said characters and means blockable by said connecting means for applying an AC erasing signal to the common electrodes of said characters, and means synchronized with said sequential means for selectively applying an actuating potential to corresponding ones of said individually energizable electrodes of said characters in parallel.
Claim 2
Dependent Claim
90 words
A multiplex driving circuit for a multicharacter liquid crystal display, each of said characters including a plurality of individually actuable electrodes and a common electrode comprising: sequential means for sequentially connecting a reference potential to the common electrode of successive ones of said characters and means blockable by said connecting means for applying an AC erasing signal to the common electrodes of said characters, and means synchronized with said sequential means for selectively applying an actuating potential to corresponding ones of said individually energizable electrodes of said characters in parallel.
Claim 3
Dependent Claim
39 words
The multiplex circuit of claim 1 wherein said means synchronized with said sequential means further includes means for biasing said individually actuable electrodes of said characters to a potential below the threshold actuation potential of the liquid crystal material.
Claim 4
Dependent Claim
56 words
The multiplex circuit of claim 1 wherein said means for selectively applying an actuation potential includes means for storing an encoded indication of a character to be displayed and means for decoding said indication for applying an actuation potential to selected ones of said individually actuable electrodes for displaying the character corresponding to said encoded indication.
Claim 5
Dependent Claim
46 words
The multiplex circuit of claim 3 further including means for synchronizing the reading by said storage means of the next character to be displayed and the connection by said sequential means of said reference potential to the common electroDe of the next character to be actuated.
Claim 6
Dependent Claim
151 words
A multiplex driving circuit for a multicharacter liquid crystal display, each of said characters including a plurality of individually energizable electrodes and a common electrode, comprising: sequential means connected to the common electrodes of all of said characters including means for connecting a reference potential to the common electrode of successive ones of said characters and means blockable by said connecting means for continuously applying an AC erasing signal to the common electrodes of said characters, and means connected in parallel to the corresponding ones of said plurality of individually energizable electrodes and synchronized with said sequential means for selectively applying an actuating potential to said corresponding ones of said individually energizable electrodes of said characters in parallel for impressing an actuating potential difference between the selected individually energizable electrodes of the character whose common electrode is held at said reference potential by said sequential means and the common electrode thereof.
Claim 7
Dependent Claim
151 words
A multiplex driving circuit for a multicharacter liquid crystal display, each of said characters including a plurality of individually energizable electrodes and a common electrode, comprising: sequential means connected to the common electrodes of all of said characters including means for connecting a reference potential to the common electrode of successive ones of said characters and means blockable by said connecting means for continuously applying an AC erasing signal to the common electrodes of said characters, and means connected in parallel to the corresponding ones of said plurality of individually energizable electrodes and synchronized with said sequential means for selectively applying an actuating potential to said corresponding ones of said individually energizable electrodes of said characters in parallel for impressing an actuating potential difference between the selected individually energizable electrodes of the character whose common electrode is held at said reference potential by said sequential means and the common electrode thereof.
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) | 1977-01-14 | 1977-07-16 | 1978-01-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-14 | 1981-07-16 | 1982-01-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-14 | 1985-07-16 | 1986-01-15 | $7700.00 | Window Closed / Lapsed |