Patent EP0221307A2 successfully refreshed from Google Patents.
← Back to Patent Explorer
EP0221307A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Signal electrode drive apparatus for use in a liquid crystal display

Assignee: Casio Computer Co Ltd
•
Filing: 1986-09-18
•
Granted: —
•
Expires: 2006-09-18
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract In the signal electrode drive apparatus for use in a liquid crystal display, the signal electrode drive circuit (3a) for driving a liquid crystal display panel (LCD) is comprised of a latch circuit (2l) for latching a digitized video signal, a buffer (22), a graduation signal-forming circuit (23), an intensity modulation pulse-generating circuit (25), and an analog multiplexer (24). The latch circuit (2l) holds the video data only once during one horizontal scanning period till the next latch pulse M is generated, thus considerably reducing current dissipation.

Inventors

  • 👤 Masao Patent Dept. Hamura R&D Center Kawamura
  • 👤 Minoru Patent Dept. Hamura R&D Center Usui

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-10 01:52
CPC Classifications
H; H04; H04N; H04N3/00; H04N3/10; H04N3/12; H04N3/127

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 125 words
A signal electrode drive apparatus for use in a liquid crystal display, characterized by comprising: latch circuit means (2l) including m stages of shift registers and m buffer registers (22), one shift register in each stage successively shifting a latch pulse M in synchronism with fundamental clocks, to gen­erate m latch clocks Tl to Tm with different phases, and each of said buffer registers latching in parallel fashion the n-bit video data in synchronism with the latch clocks φTl to φTm output from said shift regis­ters, the buffer registers of each stage being coupled with said video data; and means (23) for generating signal electrode drive signals for a liquid crystal panel, by using the video data latched in the buffer register at each stage.
Claim 2
Dependent Claim 125 words
A signal electrode drive apparatus for use in a liquid crystal display, characterized by comprising: latch circuit means (2l) including m stages of shift registers and m buffer registers (22), one shift register in each stage successively shifting a latch pulse M in synchronism with fundamental clocks, to gen­erate m latch clocks Tl to Tm with different phases, and each of said buffer registers latching in parallel fashion the n-bit video data in synchronism with the latch clocks φTl to φTm output from said shift regis­ters, the buffer registers of each stage being coupled with said video data; and means (23) for generating signal electrode drive signals for a liquid crystal panel, by using the video data latched in the buffer register at each stage.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Maintenance schedule is calculated for granted US utility patents.

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag