Liquid crystal projector

• US 7,209,103 B2
• Filed: 02/19/2003
• Issued: 04/24/2007
• Est. Priority Date: 02/19/2002
• Status: Expired due to Fees

• Current Assignee: Panasonic Liquid Crystal Display Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Hitachi Device Engineering Co., Ltd. (Hitachi, Ltd.), Hitachi, Ltd.
• Inventors: Nakagawa, Hideki, Maeda, Toshio, Watanabe, Akihiro, Maruoka, Yoshio, Misonou, Toshiki
• Primary Examiner(s): Awad; Amr A.
• Assistant Examiner(s): HOLTON, STEVEN E
• Application Number:
  US10/367,698
• Publication Number:
  US 20030156086A1
• Time in Patent Office: 1,525 Days
• Field of Search: 345204-206, 345/698, 345 87- 92, 345/96, 345/98
• US Class Current: 345/87
• CPC Class Codes: G06F 3/14 Digital output to display device ; Cooperation and interconnection of the display device with other functional units
• CPC Class Codes: G09G 2300/0876 Supplementary capacities in pixels having special driving circuits and electrodes instead of being connected to common electrode or ground; Use of additional capacitively coupled compensation electrodes
• CPC Class Codes: G09G 2320/0285 using tables for spatial correction of display data
• CPC Class Codes: G09G 2320/0606 Manual adjustment
• CPC Class Codes: G09G 2320/0626 for control of overall brightness
• CPC Class Codes: G09G 2320/066 for control of contrast
• CPC Class Codes: G09G 2320/0673 for control of gamma adjustment, e.g. selecting another gamma curve
• CPC Class Codes: G09G 2330/06 Handling electromagnetic interferences [EMI], covering emitted as well as received electromagnetic radiation
• CPC Class Codes: G09G 2340/04 Changes in size, position or resolution of an image
• CPC Class Codes: G09G 3/3611 Control of matrices with row and column drivers
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: G09G 5/006 Details of the interface to the display terminal specific for a display terminal using a CRT G09G1/167; using a flat panel G09G3/2096; circuits for interfacing with colour displays G09G5/04
• CPC Class Codes: H04N 9/3105 for displaying all colours simultaneously, e.g. by using two or more electronic spatial light modulators simultaneous projection in colour photography G03B33/10; beam splitting or combining systems per se G02B27/10

Abstract

A projector includes a liquid crystal display device has a liquid crystal display panel and a display control device coupled to the liquid crystal display panel. The display control device is composed of a first section for receiving an externally supplied video signal, and a second section succeeding the first section and coupled to the liquid crystal display panel. The second section is formed of a circuit for amplifying and converting the video signal into an ac signal supplied from the first section, and a drive pulse circuit for outputting drive pulses for driving the liquid crystal display panel. The first section and the second section are fabricated on first and second substrates separate from each other, respectively. The second section is disposed proximately to the liquid crystal display panel, and the first section and the second section are coupled via a flexible cable.

Claims

1. A liquid crystal projector comprising:

a liquid crystal display device having three liquid crystal display panels and a display control device coupled to said three liquid crystal display panels; and

an optical system which projects an image of said liquid crystal display device therefrom;

wherein said display control device comprises a first section for receiving an externally supplied video signal, and a second section succeeding said first section and coupled to said three liquid crystal display panels;

wherein said first section comprises a circuit which preprocesses said externally supplied video signal and outputs the preprocessed video signal;

wherein said second section comprises three circuit systems, and each of said three circuit systems amplifies and converts said preprocessed video signal supplied from said first section into an ac signal, increasing a data rate of said video signal by a factor of two or more and outputs drive pulses for driving a corresponding one of said three liquid crystal display panels;

wherein said first section is fabricated on a first substrate, said three circuit systems of said second section are fabricated on three second substrates, respectively, and said first and three second substrates are separated from each other;

wherein each of said three second substrates is disposed proximately to a corresponding one of said three liquid crystal display panels; and

wherein each of said three second substrates is electrically coupled to said first substrate via a corresponding one of three flexible cables.

2. A liquid crystal projector as claimed in claim 1,

wherein said second section includes at least one of

a circuit for performing data rate conversion of said video signal,

a circuit for performing gamma correction of said video signal,

a circuit for performing display resolution conversion of said video signal,

a digital-to-analog converter for converting said video signal in digital form to an analog signal,

a sample-and-hold circuit for sampling and holding said video signal, and

a circuit for phase-expanding said video signal.

3. A projector as claimed in claim 2, wherein the flexible cables are ribbon-like cables.

4. A projector as claimed in claim 2, wherein the flexible cables are foldable ribbon-like cables.

5. A liquid crystal projector as claimed in claim 1,

wherein said video signal is supplied to said second section from said first section in differential-amplitude-mode.

6. A projector as claimed in claim 5, wherein the flexible cables are ribbon-like cables.

7. A projector as claimed in claim 5, wherein the flexible cables are foldable ribbon-like cables.

wherein said video signal is supplied to said second section from said first section in differential-amplitude-mode.

8. A liquid crystal projector as claimed in claim 1,

wherein each of said three second substrates is one of a pair of substrates sandwiching a liquid crystal layer of a corresponding one of said three liquid crystal display panels.

9. A projector as claimed in claim 8, wherein the flexible cables are ribbon-like cables.

10. A projector as claimed in claim 8, wherein the flexible cables are foldable ribbon-like cables.

11. A liquid crystal projector as claimed in claim 1

wherein each of said three second substrates is attached on an outer surface of one of a pair of substrates sandwiching a liquid crystal layer of a corresponding one of said three liquid crystal display panels.

12. A projector as claimed in claim 11, wherein the flexible cables are ribbon-like cables.

13. A projector as claimed in claim 11, wherein the flexible cables are foldable ribbon-like cables.

14. A liquid crystal projector as claimed in claim 1

wherein said first section is fabricated on a first substrate, each of said three circuit systems of said second section is fabricated on an outer surface of a first one of a pair of substrates sandwiching a liquid crystal layer of a corresponding one of said three liquid crystal display panels, and said first substrate and the first ones of the substrates are separated from each other.

15. A projector as claimed in claim 14, wherein the flexible cables are ribbon-like cables.

16. A projector as claimed in claim 14, wherein the flexible cables are foldable ribbon-like cables.

17. A projector as claimed in claim 1, wherein the flexible cables are ribbon-like cables.

18. A projector as claimed in claim 1, wherein the flexible cables are foldable ribbon-like cables.