Reflective type liquid crystal display device

• US 6,784,956 B2
• Filed: 07/20/2001
• Issued: 08/31/2004
• Est. Priority Date: 07/21/2000
• Status: Expired due to Term

• Current Assignee: Panasonic Liquid Crystal Display Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Hitachi, Ltd., Hitachi Device Engineering Co., Ltd. (Japan Display Incorporated)
• Inventors: Nakagawa, Hideki, Ohashi, Takeshi, Nakamura, Shigeo, Matsumoto, Katsumi, Kitajima, Kenji, Takemoto, Iwao, Iguchi, Atsumu, Sakai, Kouki, Ito, Eiichiro, Furihata, Masatoshi
• Primary Examiner(s): Jackson, Jerome
• Assistant Examiner(s): Díaz, José R.
• Application Number:
  US09/908,856
• Publication Number:
  US 20020008800A1
• Time in Patent Office: 1,138 Days
• Field of Search: 349/110, 349/155, 349/156, 349/44, 349/113
• US Class Current: 349/110
• CPC Class Codes: G02F 1/136209 Light shielding layers, e.g. black matrix, incorporated in the active matrix substrate, e.g. structurally associated with the switching element
• CPC Class Codes: G02F 1/136277 formed on a semiconductor substrate, e.g. of silicon

Abstract

A liquid crystal display device includes a first substrate, a second substrate, a liquid crystal layer sandwiched between the first and second substrate, plural reflective electrodes arranged on a surface of the first substrate on a liquid crystal layer side thereof, each of the reflective electrodes being adapted to be supplied with a video signal; and plural light-blocking conductive films disposed below the reflective electrodes with an insulating layer interposed between the light-blocking films and the reflective electrodes. Each of the light-blocking films is electrically connected to a corresponding one of the reflective electrodes, and is disposed to cover at least a portion of spacings between the corresponding one of the reflective electrodes and ones of the reflective electrodes adjacent thereto.

Claims

1. A liquid crystal display device comprising:

a first substrate;

a second substrate;

a liquid crystal layer sandwiched between said first substrate and said second substrate;

a plurality of reflective electrodes arranged on a surface of said first substrate on a liquid crystal layer side thereof,

each of said plurality of reflective electrodes being adapted to be supplied with a video signal;

a counter electrode disposed on a surface of said second substrate on a liquid crystal layer side thereof;

a plurality of second light-blocking conductive films disposed below said plurality of reflective electrodes with an insulating layer interposed between said plurality of second light-blocking films and said plurality of reflective electrodes; and

a first light-blocking film disposed below said plurality of second light-blocking conductive films and formed to cover spacing between said plurality of second light-blocking conductive films;

each of said plurality of second light-blocking films being electrically connected to a corresponding one of said plurality of reflective electrodes,

each of said plurality of second light-blocking films being disposed to cover at least a portion of spacings between said corresponding one of said plurality of reflective electrodes and ones of said plurality of reflective electrodes adjacent to said corresponding one of said plurality of reflective electrodes.

wherein each of said plurality of second light-blocking films forms a capacitance with said first light-blocking film, and a polarity of a voltage supplied to each of said plurality of second light-blocking conductive films is inverted with respect to a voltage applied on said counter electrode at specified time intervals.

2. A liquid crystal display device comprising:

a driving-circuit substrate;

a transparent substrate;

a liquid crystal layer sandwiched between said driving-circuit substrate and said transparent substrate;

a plurality of reflective electrodes arranged on a surface of said driving-circuit substrate on a liquid crystal layer side thereof;

a counter electrode disposed on a surface of said transparent substrate on a liquid crystal layer side thereof;

a plurality of semiconductor switching elements disposed below said plurality of reflective electrodes, each of said plurality of semiconductor switching elements being configured to supply a video signal to a corresponding one of said plurality of reflective electrodes;

a first light-blocking film for covering said plurality of semiconductor switching elements; and

a plurality of second light-blocking films each disposed to cover at least a portion of spacings between adjacent ones of said plurality of reflective electrodes,

each of said plurality of second light-blocking films being electrically connected to a corresponding one of said plurality of reflective electrodes,

wherein each of said plurality of second light-blocking films forms a capacitance with said first light-blocking film, and a polarity of said video signal supplied to each of said plurality of reflective electrodes is inverter with respect to a voltage applied on said counter electrode by varying a voltage supplied to said first light-blocking film.

3. A liquid crystal display device comprising:

a first substrate;

a second substrate;

spacers made of resin for establishing a spacing between said first substrate and said second substrate;

a peripheral frame made of said resin and interposed between said first substrate and said second substrate;

a liquid crystal component filled in a space enclosed by said first substrate, said second substrate and said peripheral frame;

a plurality of reflective electrodes arranged on a surface of said first substrate on a liquid crystal layer side thereof;

a counter electrode disposed on a surface of said second substrate on a liquid crystal layer side thereof;

a plurality of dummy electrodes disposed between said plurality of reflective electrodes and said peripheral frame, each of said plurality of dummy electrodes being supplied with a dummy-electrode signal;

a plurality of semiconductor switching elements disposed below said plurality of reflective electrodes, each of said plurality of semiconductor switching elements being configured to supply a video signal to a corresponding one of said plurality of reflective electrodes;

a first light-blocking film for covering said plurality of semiconductor switching elements; and

a plurality of second light-blocking conductive films each disposed to cover at least a portion of spacings between adjacent ones of said plurality of reflective electrodes.

wherein each of said plurality of second light-blocking films forms a capacitance with said first light-blocking film, and a polarity of said video signal supplied to each of said plurality of second light-blocking conductive films is inverted with respect to a voltage applied on said counter electrode at specified time intervals.

4. A liquid crystal display device according to claim 3, wherein said dummy-electrode signal is such that said dummy electrodes, disposed between said plurality of reflective electrodes and said peripheral frame, provide a black display.

5. A liquid crystal display device according to claim 3, wherein a polarity of said dummy-electrode signal applied to one of said plurality of dummy electrodes is reversed in synchronism with a said video signal applied to one of said plurality of reflective electrodes adjacent to said one of said plurality of dummy electrodes.