Liquid crystal device and electronic apparatus

• US 8,599,337 B2
• Filed: 11/26/2007
• Issued: 12/03/2013
• Est. Priority Date: 03/12/2007
• Status: Active Grant

• Current Assignee: Japan Display West Incorporated (Japan Display Incorporated)
• Original Assignee: Japan Display West Incorporated (Japan Display Incorporated)
• Inventors: Higa, Masakatsu
• Primary Examiner(s): NGO, HUYEN LE
• Application Number:
  US11/984,971
• Publication Number:
  US 20080225209A1
• Time in Patent Office: 2,199 Days
• Field of Search: 349/114, 349/106, 349/110, 349/117, 349155-157, 349/141
• US Class Current: 349/114
• 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 1/133565 inside the LC elements, i.e. between the cell substrates
• CPC Class Codes: G02F 1/13363 Birefringent elements, e.g. for optical compensation
• CPC Class Codes: G02F 1/13394 spacers regularly patterned on the cell subtrate, e.g. walls, pillars G02F1/133377 takes precedence
• 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 1/134372 for fringe field switching [FFS] where the common electrode is not patterned

Abstract

A liquid crystal device in which a horizontal electric field is applied to a liquid crystal layer of a transflective type. Spacers are disposed to set a distance between substrates and to prevent deterioration of display quality by eliminating thickness non-uniformity of an alignment layer due to the presence of a retardation layer. Slits are provided in the retardation layer regions to prevent deterioration of display quality by preventing dissolution and flow of an ingredient of the retardation layer to the liquid crystal layer side through the alignment layers.

Claims

1. A liquid crystal device, wherein

the liquid crystal device includes a pair of first and second substrates which sandwich a liquid crystal layer,

the first substrate includes a first electrode, a second electrode for generating an electric field between with the first electrode, and a reflection layer extending in a predetermined direction, and the second substrate includes a plurality of coloring layers and a retardation layer that gives a retardation of ½

wavelength,

a transmissive display area for performing transmissive display by transmitting the light introduced into the liquid crystal layer from the first substrate side to the second substrate side and a reflective display area for performing reflective display by reflecting the light introduced into the liquid crystal layer form the second substrate side to the second substrate side by the reflection layer are provided in a sub pixel area corresponding to the area in which the first electrode of the first substrate and the second substrate are overlapped with each other,

a thickness of the liquid crystal layer in the transmissive display area is set at least larger than a thickness of the liquid crystal layer in the reflective display area,

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

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

wavelength,

a first polarizer having a first optical axis is provided on the first substrate at the side opposite to the liquid crystal layer side and a second polarizer having a second optical axis perpendicular to the first optical axis is provided on the second substrate at the side opposite to the liquid crystal layer side,

any one of the first optical axis of the first polarizer and the second optical axis of the second polarizer is set in parallel to an alignment axis of liquid crystal molecules of the liquid crystal layer,

the retardation layer is provided between the liquid crystal layer and the second polarizer and at a position at least corresponding to the reflective display area, the retardation layer extending in a predetermined direction corresponding to the predetermined direction of the reflection layer,

a spacer for setting a distance between the first substrate and the second substrate is provided at any one of the first substrate and the second substrate side and in the area not overlapping with the retardation layer in plan view,

a light shielding layer is provided at the second substrate side and at least between the sub pixel areas adjacent each other in a row direction, and

the spacer is provided at a position overlapping with the light shielding layer in plan view and the light shielding layer does not extend into a region over the retardation layer, and

wherein a slit is located on the second substrate in the retardation layer at a position corresponding to between the reflective display area provided in any of the sub pixel area and the other reflective display area provided in the other sub pixel area adjacent each other in a predetermined direction with respect to the any of the sub pixel area.

2. The liquid crystal device according to claim 1, wherein the spacer is provided at the second substrate side.

3. The liquid crystal device according to claim 1, wherein the spacer is provided in an area in which the thickness of the liquid crystal layer is larger than the thickness of the liquid crystal layer in the reflective display area.

4. The liquid crystal device according to claim 1, wherein, the slit is provided between some of the sub pixel areas adjacent each other in the predetermined direction and the slit is provided between some of the sub pixel areas adjacent each other in the predetermined direction in the retardation layer.

5. The liquid crystal device according to claim 1, wherein the spacer is provided at the position most apart from the slit in any of the sub pixel area.

6. The liquid crystal device according to claim 5, wherein the spacer is not positioned on an extended line of the slit in the extending direction of the slit.

7. The liquid crystal device according to claim 1, wherein the slit is extended into the retardation layer in the predetermined direction of the retardation layer.

9. An electronic apparatus comprising the liquid crystal device according to claim 1 as a display unit.

8. A liquid crystal device, wherein

the liquid crystal device includes a pair of first and second substrates which sandwich a liquid crystal layer,

the first substrate includes a first electrode, a second electrode for generating an electric field between with the first electrode, and a reflection layer, and the second substrate includes a plurality of coloring layers and a retardation layer that gives a retardation of ½

wavelength,

a transmissive display area for performing transmissive display by transmitting the light introduced into the liquid crystal layer from the first substrate side to the second substrate side and a reflective display area for performing reflective display by reflecting the light introduced into the liquid crystal layer form the second substrate side to the second substrate side by the reflection layer are provided in a sub pixel area corresponding to the area in which the first electrode of the first substrate and the second substrate are overlapped with each other,

a thickness of the liquid crystal layer in the transmissive display area is set at least larger than a thickness of the liquid crystal layer in the reflective display area,

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

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

wavelength,

a first polarizer having a first optical axis is provided on the first substrate at the side opposite to the liquid crystal layer side and a second polarizer having a second optical axis perpendicular to the first optical axis is provided on the second substrate at the side opposite to the liquid crystal layer side,

any one of the first optical axis of the first polarizer and the second optical axis of the second polarizer is set in parallel to an alignment axis of liquid crystal molecules of the liquid crystal layer,

wherein the retardation layer is provided between the liquid crystal layer and the second polarizer and at a position at least corresponding to the reflective display area,

a light shielding layer is provided at the second substrate side and at least between the sub pixel areas adjacent each other in a row direction, and

the spacer is provided at a position overlapping with the light shielding layer in plan view and the light shielding layer does not extend into a region over the retardation layer, and

the retardation layer includes a slit located on the second substrate at a position corresponding to between the reflective display area provided in any of the sub pixel area and the other reflective display area provided in the other sub pixel area adjacent each other in a predetermined direction with respect to the any of the sub pixel area.