LIQUID CRYSTAL DEVICE AND ELECTRONIC APPARATUS

• US 20100045903A1
• Filed: 08/06/2009
• Published: 02/25/2010
• Est. Priority Date: 08/22/2008
• Status: Abandoned Application

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: KOMA, Norio, ARUGA, Shuji
• Application Number:
  US12/536,833
• Publication Number:
  US 20100045903A1
• Time in Patent Office: Days
• US Class Current: 349/96
• CPC Class Codes: G02F 1/133371 Cells with varying thickness of the liquid crystal layer
• CPC Class Codes: G02F 1/133555 Transflectors
• CPC Class Codes: G02F 1/133707 Structures for producing distorted electric fields, e.g. bumps, protrusions, recesses, slits in pixel electrodes
• CPC Class Codes: G02F 1/133784 by rubbing
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
• CPC Class Codes: G02F 1/134381 Hybrid switching mode, i.e. for applying an electric field with components parallel and orthogonal to the substrates
• CPC Class Codes: G02F 1/13712 the liquid crystal having negative dielectric anisotropy

Abstract

A liquid crystal device includes a plurality of pixels. Each of the plurality of pixels includes a liquid crystal layer interposed between first and second substrates facing each other and having liquid crystal molecules to be driven by an applied electric field, a first electrode formed on a side of the first substrate facing the second substrate, and a second electrode formed on a side of the first substrate facing the second substrate and interposing an insulating layer together with the first electrode. A reflective display area for reflective display and a transmissive display area for transmissive display are formed within each of the pixels. The liquid crystal molecules have a negative dielectric anisotropy.

Claims

1. A liquid crystal device comprising:

a plurality of pixels,

wherein each of the plurality of pixels includes a liquid crystal layer interposed between first and second substrates facing each other and having liquid crystal molecules to be driven by an applied electric field, a first electrode formed on a side of the first substrate facing the second substrate, and a second electrode formed on a side of the first substrate facing the second substrate and interposing an insulating layer together with the first electrode,

wherein a reflective display area for reflective display and a transmissive display area for transmissive display are formed within each of the pixels, and

wherein the liquid crystal molecules have a negative dielectric anisotropy.

2. The liquid crystal device according to claim 1, further comprising:

a first polarizing plate which has a transmission axis oriented in a first direction and is formed on a side of the first substrate opposite to the second substrate;

a second polarizing plate which has a transmission axis oriented in a direction perpendicular to the first direction and is formed on a side of the second substrate opposite to the first substrate; and

alignment films which are respectively formed on the sides of the first and second substrates facing the liquid crystal layer and subjected to a rubbing process in the first direction or the direction perpendicular to the first direction,

wherein one of the first and second electrodes on the side of the liquid crystal layer has (i) a first slit extending in a direction forming 45°

with respect to the first direction in the reflective display area and (ii) a second slit extending in a direction substantially perpendicular to a rubbing direction in the transmissive display area, and

wherein retardation of the liquid crystal layer in the reflective display area is a ¼

wavelength and retardation of the liquid crystal layer in the transmissive display area is a ½

wavelength.

3. The liquid crystal device according to claim 1, further comprising:

a first polarizing plate which has a transmission axis oriented in a first direction and is formed on a side of the first substrate opposite to the second substrate;

a second polarizing plate which has a transmission axis oriented in a direction perpendicular to the first direction and is formed on a side of the second substrate opposite to the first substrate; and

alignment films which are respectively formed on the sides of the first and second substrates facing the liquid crystal layer and subjected to a rubbing process in the first direction,

wherein one of the first and second electrodes on the side of the liquid crystal layer has (i) a first slit extending in a direction forming 45°

with respect to the first direction in the reflective display area and (ii) a second slit extending in the direction forming 45°

with respect to the first direction in the transmissive display area, and

wherein retardation of the liquid crystal layer in the reflective display area is a ¼

wavelength and retardation of the liquid crystal layer in the transmissive display area is a ½

wavelength.

4. The liquid crystal device according to claim 2,

wherein the second electrode includes a second electrode for reflective display of the reflective display area and a second electrode for transmissive display of the transmissive display area, and

wherein the liquid crystal device further comprises a voltage applying circuit which applies a voltage to the first electrode so that a polarity of a voltage applied to the second electrode for reflective display and a polarity of a voltage applied to the second electrode for transmissive display are opposite to each other.

5. The liquid crystal device according to claim 4, wherein the first electrode is a pixel electrode and the second electrode is a common electrode.

6. An electronic apparatus comprising the liquid crystal device according to claim 1.