Reflection type liquid crystal display device and method of manufacturing the same

• US 5,699,135 A
• Filed: 12/10/1996
• Issued: 12/16/1997
• Est. Priority Date: 10/18/1994
• Status: Expired due to Term

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Hisatake, Yuzo, Watanabe, Ryoichi, Murayama, Akio, Hatoh, Hitoshi, Sato, Makiko
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): TON, MINH TOAN T
• Application Number:
  US08/763,084
• Time in Patent Office: 371 Days
• Field of Search: 349/84, 349/106, 349/111, 349/113, 349/112, 349/165
• US Class Current: 349/113
• CPC Class Codes: G02F 1/133504 Diffusing, scattering, diffracting elements associated to illuminating devices G02F1/133606
• CPC Class Codes: G02F 1/133512 Light shielding layers, e.g. black matrix G02F1/136209 takes precedence
• CPC Class Codes: G02F 1/133526 Lenses, e.g. microlenses or Fresnel lenses
• CPC Class Codes: G02F 1/133553 Reflecting elements associated to illuminating devices G02F1/133605
• CPC Class Codes: G02F 1/13725 based on guest-host interaction G02F1/13762, G02F1/13737, take precedence
• CPC Class Codes: G02F 2203/02 reflective

Abstract

A reflecting type liquid crystal display device having, a first substrate provided on one main surface thereof with a first electrode comprising a plurality of pixel electrodes arrayed in a matrix form and a wiring interposed between these pixel electrodes, the first substrate being disposed on an observation side, a second substrate provided on one main surface thereof with a second electrode and disposed to face the first substrate in such a manner that the surface bearing the second electrode faces to the surface bearing the first electrode, a liquid crystal composition layer interposed between the first substrate and the second substrate, and a white reflecting layer formed on a region of the surface of the first substrate where the first electrode is not formed.

Claims

1. A reflecting type liquid crystal display device comprising;

a first substrate provided on one main surface thereof with a first electrode and disposed on an observation side;

a second substrate provided on one main surface thereof with a second electrode and disposed to face said first substrate in such a manner that said one main surface bearing said second electrode faces to said one main surface bearing said first electrode;

a liquid crystal composition layer interposed between said first substrate and said second substrate;

a modulation region which corresponds to a region of said first electrode and is capable of modulating the intensity of reflection of incident light in accordance with a response of said liquid crystal composition to a voltage applied to between said first substrate and said second substrate;

a non-modulation region occupying a region other than said modulation region; and

a white reflecting layer formed on at least a portion of said non-modulation region of any one of surfaces of said first substrate.

2. The reflecting type liquid crystal display device according to claim 1, wherein said white reflecting layer is mounted on the surface of the first substrate where the first electrode is formed.

3. The reflecting type liquid crystal display device according to claim 1, wherein said white reflecting layer is formed of a resist material having a white pigment dispersed therein.

4. The reflecting type liquid crystal display device according to claim 3, wherein said white pigment comprises as a main component TiO₂.

5. The reflecting type liquid crystal display device according to claim 1, wherein at least one of the first and the second substrate is provided with a color filter, and said white reflecting layer is formed on a surface of the substrate where said electrode is formed and at a portion of the surface where said color filter is not formed.

6. The reflecting type liquid crystal display device according to claim 1, wherein said liquid crystal composition contains a dichroic dye.

7. The reflecting type liquid crystal display device according to claim 1, wherein said liquid crystal composition is a nematic liquid crystal containing a black dye and exhibiting a positive dielectric anisotropy, molecules thereof being homogeneously oriented between the first and the second substrates, and a quarter wavelength plate and a second reflecting plate are mounted on the second substrate.

8. The reflecting type liquid crystal display device according to claim 1 wherein said white reflecting layer functions as an intersubstrate spacer for controlling the space between the first and the second substrates.

9. A reflecting type liquid crystal display device comprising;

a first substrate provided on one main surface thereof with a first electrode comprising a plurality of pixel electrodes arrayed in a matrix form and a wiring interposed between these pixel electrodes, said first substrate being disposed on an observation side;

a second substrate provided on one main surface thereof with a second electrode and disposed to face said first substrate in such a manner that said one main surface bearing said second electrode faces to said one main surface bearing said first electrode;

a liquid crystal composition layer interposed between said first substrate and said second substrate; and

a white reflecting layer formed on a region of said one main surface of said first substrate where said first electrode is not formed.

10. The reflecting type liquid crystal display device according to claim 9, wherein said white reflecting layer is formed of a resist material having a white pigment dispersed therein.

11. The reflecting type liquid crystal display device according to claim 10, wherein said white pigment comprises as a main component TiO₂.

12. The reflecting type liquid crystal display device according to claim 9, wherein said liquid crystal composition contains a dichroic dye.

13. The reflecting type liquid crystal display device according to claim 9, wherein said liquid crystal composition is a nematic liquid crystal containing a black dye and exhibiting a positive dielectric anisotropy, molecules thereof being homogeneously oriented between the first and the second substrates, and a quarter wavelength plate and a second reflecting plate are mounted on the second substrate.

14. The reflecting type liquid crystal display device according to claim 9, wherein said white reflecting layer functions as an intersubstrate spacer for controlling the space between the first and the second substrates.

15. A method of manufacturing a reflecting type liquid crystal display device comprising the steps of;

forming a transparent conductive layer on one surface of a first substrate;

forming a resist pattern on said transparent conductive layer;

forming an electrode pattern by etching said transparent conductive layer with said resist pattern being used as a mask;

forming a white layer on a surface of said first substrate on which said electrode pattern and resist pattern are disposed; and

forming a white reflecting layer on a region other than where said electrode pattern is formed by removing said resist pattern together with said white layer formed over said resist pattern.

16. A method of manufacturing a reflecting type liquid crystal display device comprising the steps of;

forming a color layer on one main surface of a first substrate;

forming a resist pattern on said transparent conductive layer;

forming a color filter pattern comprising said color layer by etching said color layer with said resist pattern being used as a mask;

forming a white layer on a surface of said first substrate on which said color filter pattern and resist pattern are disposed; and

forming a white reflecting layer on a region other than where said color layer is formed by removing said resist pattern together with said white layer formed over said resist pattern.