Active matrix type of a liquid crystal display apparatus which can keep a desirable aperture ratio, drive a liquid crystal at a low voltage, and improve a responsive speed and further protect a coloration from an oblique field

• US 20010043304A1
• Filed: 05/21/2001
• Published: 11/22/2001
• Est. Priority Date: 05/19/2000
• Status: Active Grant

• Current Assignee: NLT Technologies, Ltd. (Tianma Microelectronics Company Limited)
• Original Assignee: NEC Corporation
• Inventors: Matsumoto, Kimikazu
• Granted Patent: US 6,624,866 B2
• Time in Patent Office: Days
• US Class Current: 349/141
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]

Abstract

An active matrix type of a liquid crystal display apparatus, includes a pair of substrates, a liquid crystal layer and a pixel electrode and a common electrode and a transparent auxiliary electrode. The liquid crystal layer is provided between the pair of substrates. The pixel electrode and the common electrode are provided on at least one side of the pair of substrates. The pixel electrode and the common electrode are provided at established intervals to be shaped like teeth of a comb to generate an electric field substantially parallel to the pair of substrates in the liquid crystal layer. The transparent auxiliary electrode is provided through an insulating film above the common electrode. The same voltage as that of the common electrode is applied to the transparent auxiliary electrode such that the electric field applied to the liquid crystal layer is strengthened.

Claims

1. An active matrix type of a liquid crystal display apparatus, comprising:

a pair of substrates;

a liquid crystal layer provided between said pair of substrates;

a pixel electrode and a common electrode provided on at least one side of said pair of substrates, wherein said pixel electrode and said common electrode are provided at established intervals to be shaped like teeth of a comb to generate an electric field substantially parallel to said pair of substrates in said liquid crystal layer; and

a transparent auxiliary electrode provided through an insulating film above said common electrode, wherein a same voltage as that of said common electrode is applied to said transparent auxiliary electrode such that said electric field applied to said liquid crystal layer is strengthened.

8. The active matrix type of the liquid crystal display apparatus according to any one of

claims 1

to

5

, wherein said pixel electrode and said common electrode and said transparent auxiliary electrode are shaped like teeth of said comb to generate said electric field, and

wherein each of said pixel electrode and said common electrode and said transparent auxiliary electrode is shaped like a straight line.

9. The active matrix type of the liquid crystal display apparatus according to any one of

claims 1

to

5

, wherein said pixel electrode and said common electrode and said transparent auxiliary electrode are shaped like teeth of said comb to generate said electric field, and

wherein at least one of said pixel electrode and said common electrode and said transparent auxiliary electrode is shaped like bent.

10. The active matrix type of the liquid crystal display apparatus according to

claim 9

, wherein said at least one of said pixel electrode and said common electrode and said transparent auxiliary electrode is created in a form of a triangular notch.

11. The active matrix type of the liquid crystal display apparatus according to any one of

claims 1

to

7

, wherein said pixel electrode and said common electrode and said transparent auxiliary electrode are shaped like teeth of said comb to generate said electric field, and

wherein a width of said transparent auxiliary electrode is wider than those of said pixel electrode and said common electrode such that a space between said teeth of said comb is lessened.

12. The active matrix type of the liquid crystal display apparatus according to

claim 8

, wherein said pixel electrode and said common electrode and said transparent auxiliary electrode are shaped like teeth of said comb to generate said electric field, and

wherein a width of said transparent auxiliary electrode is wider than those of said pixel electrode and said common electrode such that a space between said teeth of said comb is lessened.

13. The active matrix type of the liquid crystal display apparatus according to

claim 9

, wherein said pixel electrode and said common electrode and said transparent auxiliary electrode are shaped like teeth of said comb to generate said electric field, and

wherein a width of said transparent auxiliary electrode is wider than those of said pixel electrode and said common electrode such that a space between said teeth of said comb is lessened.

14. The active matrix type of the liquid crystal display apparatus according to

claim 10

, wherein said pixel electrode and said common electrode and said transparent auxiliary electrode are shaped like teeth of said comb to generate said electric field, and

wherein a width of said transparent auxiliary electrode is wider than those of said pixel electrode and said common electrode such that a space between said teeth of said comb is lessened.

15. The active matrix type of the liquid crystal display apparatus according to

claim 11

, wherein a center line of a width of said transparent auxiliary electrode is a same as that of one of said pixel electrode and said common electrode.

16. The active matrix type of the liquid crystal display apparatus according to

claim 12

, wherein a center line of a width of said transparent auxiliary electrode is a same as that of one of said pixel electrode and said common electrode.

17. The active matrix type of the liquid crystal display apparatus according to

claim 13

, wherein a center line of a width of said transparent auxiliary electrode is a same as that of one of said pixel electrode and said common electrode.

18. The active matrix type of the liquid crystal display apparatus according to

claim 14

, wherein a center line of a width of said transparent auxiliary electrode is a same as that of one of said pixel electrode and said common electrode.

19. The active matrix type of the liquid crystal display apparatus according to any one of

claims 1

to

7

, wherein a material of said transparent auxiliary electrode is an ITO.

20. The active matrix type of the liquid crystal display apparatus according to

claim 8

, wherein a material of said transparent auxiliary electrode is an ITO.

2. An active matrix type of a liquid crystal display apparatus, comprising:

a pair of substrates;

a liquid crystal layer provided between said pair of substrates;

a pixel electrode and a common electrode provided on at least one side of said pair of substrates, wherein said pixel electrode and said common electrode are provided at established intervals to be shaped like teeth of a comb to generate an electric field substantially parallel to said pair of substrates in said liquid crystal layer;

a first transparent auxiliary electrode provided above said pixel electrode; and

a second transparent auxiliary electrode provided above said common electrode through a contact hole electrically connected to said first transparent auxiliary electrode, and

wherein said first transparent auxiliary electrode is formed on a same layer as that on which said second transparent auxiliary electrode is formed.

5. The active matrix type of the liquid crystal display apparatus according to

claim 2

, wherein said liquid crystal display apparatus includes a plurality of said contact holes per a display pixel of said liquid crystal display apparatus.

3. An active matrix type of a liquid crystal display apparatus, comprising:

a pair of substrates;

a liquid crystal layer provided between said pair of substrates;

a pixel electrode and a common electrode provided on at least one side of said pair of substrates, wherein said pixel electrode and said common electrode are provided at established intervals to be shaped like teeth of a comb to generate an electric field substantially parallel to said pair of substrates in said liquid crystal layer;

a first transparent auxiliary electrode provided above said pixel electrode; and

a second transparent auxiliary electrode provided above said common electrode through a contact hole electrically connected to said first transparent auxiliary electrode, and

wherein said first transparent auxiliary electrode is formed on a first layer and said second transparent auxiliary electrode is formed through an insulating film on a second layer different from said first layer.

6. The active matrix type of the liquid crystal display apparatus according to

claim 3

, wherein said liquid crystal display apparatus includes a plurality of said contact holes per a display pixel of said liquid crystal display apparatus.

4. An active matrix type of a liquid crystal display apparatus, comprising:

a pair of substrates;

a liquid crystal layer provided between said pair of substrates;

a pixel electrode and a common electrode provided on at least one side of said pair of substrates, wherein said pixel electrode and said common electrode are provided at established intervals to be shaped like teeth of a comb to generate an electric field substantially parallel to said pair of substrates in said liquid crystal layer; and

a transparent auxiliary electrode provided through an insulating film above a single one of said pixel electrode and said common electrode, wherein said transparent auxiliary electrode is electrically connected to said single one through a contact hole.

7. The active matrix type of the liquid crystal display apparatus according to

claim 4

, wherein said liquid crystal display apparatus includes a plurality of said contact holes per a display pixel of said liquid crystal display apparatus.