TRANSFLECTIVE LCD UNIT

• US 20090122211A1
• Filed: 11/10/2008
• Published: 05/14/2009
• Est. Priority Date: 11/08/2007
• Status: Active Grant

• Current Assignee: NLT Technologies, Ltd. (Tianma Microelectronics Company Limited)
• Original Assignee: NEC LCD Technologies Limited (Tianma Microelectronics Company Limited)
• Inventors: SAKAMOTO, Michiaki, MORI, Kenichi, NAGAI, Hiroshi
• Granted Patent: US 8,508,699 B2
• Time in Patent Office: Days
• US Class Current: 349/42
• 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 1/134318 having a patterned common electrode
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]

Abstract

A transflective LCD unit includes a liquid crystal (LC) layer: first and second substrates sandwiching therebetween the LC layer to define an array of pixels each including a reflective area and a transmissive area; an electrode assembly for driving the LC layer such that the LC layer in the reflective area is driven in a longitudinal-electric-field mode and the LC layer in the transmissive area is driven in a lateral-electric-field mode; and a reverse-tilt control member for controlling a reverse tilt area in which a reverse tilt of LC molecules occurs near the boundary between the reflective area and the transmissive area.

Claims

1. A transflective liquid crystal display (LCD) unit comprising:

a liquid crystal (LC) layer;

first and second substrates sandwiching therebetween said LC layer to define an array of pixels in said LC layer, said pixels each including a reflective area and a transmissive area;

an electrode assembly for driving said LC layer such that said LC layer in said reflective area is driven in a longitudinal-electric-field mode and said LC layer in said transmissive area is driven in a lateral-electric-field mode; and

a reverse-tilt control member disposed in a vicinity of a boundary between said reflective area and said transmissive area for controlling a reverse tilt area in which a reverse tilt of LC molecules occurs in said LC layer.

2. The transflective LCD unit according to claim 1, wherein said reverse-tilt control member restricts said reverse tilt area within an area of said LC layer that is driven in a lateral-electric-field mode.

3. The transflective LCD unit according to claim 2, wherein said electrode assembly includes a reflective-area pixel electrode, a transmissive-area pixel electrode and a transmissive-area common electrode formed on said first substrate, and a reflective-area common electrode formed on said second substrate, and said reflective-area common electrode having an extension protruding toward said transmissive area across said boundary.

4. The transflective LCD unit according to claim 1, wherein said electrode assembly includes a reflective-area pixel electrode, a transmissive-area pixel electrode and a transmissive-area common electrode formed on said first substrate, and a reflective-area common 5 electrode formed on said second substrate, and said reverse-tilt control member restricts said reverse tilt area within a vicinity of said second substrate.

5. The transflective LCD unit according to claim 4, wherein said electrode assembly further comprises a subsidiary electrode formed on said second substrate and applied with a signal applied to said reflective-area common electrode.

6. The transflective LCD unit according to claim 4, wherein said reflective area includes a reflection film formed on said first substrate and applied with a signal applied to said reflective-area common electrode, and said reflection film has an extension protruding beyond said reflective-area common electrode toward said transmissive area.

7. The transflective LCD unit according to claim 4, further comprising a switching member for providing a data signal to said pixel reflective-area and transmissive-area pixel electrodes, and a scanning line formed on said first substrate to apply a gate signal to said switching member, wherein said scanning line extends on said boundary and has a width protruding toward said transmissive area in an amount larger than an amount of protruding toward said reflective area.

8. The transflective LCD unit according to claim 4, wherein said electrode assembly further comprises a subsidiary electrode formed on said first substrate in a vicinity of said boundary and applied with a gate signal that is applied to a gate of a switching member for applying a data signal to at least one of said reflective-area pixel and transmissive-area pixel electrodes.

9. The transflective LCD unit according to claim 1, wherein said reflective-area common electrode and said transmissive-area common electrode are applied with different signals.

10. A terminal device including the transflective LCD unit according to claim 1.