Liquid crystal display comprising first and second alignment films having first and second anchoring strengths respectively and manufacturing method thereof
View Patent ↗According to one embodiment, a liquid crystal display includes a first substrate, a second substrate and a liquid crystal layer. The first substrate includes a first line, a second line, a switching element, a pixel electrode, a common electrode, and a first alignment film. The second substrate includes a second alignment film. The liquid crystal layer includes a liquid crystal molecule kept between the first alignment film and the second alignment film. First anchoring strength is provided on the first alignment film which is a photo-alignment film, second anchoring strength is provided on the second alignment film which is a rubbing alignment film, and the first anchoring strength is substantially equal to or greater than the second anchoring strength.
1. A liquid crystal display comprising:
a first substrate comprising a first line, a second line, a switching element electrically connected to the first line and the second line, a pixel electrode electrically connected to the switching element, a common electrode formed through a plurality of pixels, and a first alignment film provided above the pixel electrode and the common electrode;
a second substrate comprising a second alignment film facing the first alignment film; and
a liquid crystal layer including a liquid crystal molecule kept between the first alignment film and the second alignment film,
wherein first anchoring strength is provided on the first alignment film which is a photo-alignment film, and second anchoring strength is provided on the second alignment film which is a rubbing alignment film, and
the first anchoring strength is substantially equal to or greater than the second anchoring strength, and
equations (1) and (2) below are satisfied if A 1 =a 1 ×10^(−a 2 ), where A 1 is the first anchoring strength provided to the first alignment film,
0< a 2 ≦4 (1)
1≦ a 1 ≦10 (2).
2. The liquid crystal display of claim 1 , wherein
the second substrate further comprises a color filter.
3. The liquid crystal display of claim 1 , wherein
a first alignment treatment direction of the first alignment film and a second alignment treatment direction of the second alignment film are parallel to an arrangement direction of the second line,
the second substrate comprises:
a light shielding layer overlapping with the first line and extending in the arrangement direction; and
a spacer provided in a position overlapping with the light shielding layer,
the first substrate and the second substrate face each other across the spacer, and
the liquid crystal layer is enclosed in a cell gap formed between the first alignment film and the second alignment film by the spacer.
4. The liquid crystal display of claim 3 , wherein
the first substrate further comprises an insulating film arranged between the pixel electrode and the common electrode,
the pixel electrode includes a slit extending along the second line and facing the common electrode, and
dielectric anisotropy of the liquid crystal molecule is negative.
5. The liquid crystal display of claim 1 , wherein
equations (3) and (4) below are satisfied if A 2 =b 1 ×10^(−b 2 ), where A 2 is the second anchoring strength provided to the second alignment film,
0< a 2 ≦b 2 ≦4 (3)
1≦ b 1 <10 (4).
6. A method of manufacturing a liquid crystal display,
the liquid crystal display comprising:
a first substrate comprising a first line, a second line, a switching element electrically connected to the first line and the second line, a pixel electrode electrically connected to the switching element, a common electrode formed through a plurality of pixels, and a first alignment film provided above the pixel electrode and the common electrode;
a second substrate comprising a second alignment film facing the first alignment film; and
a liquid crystal layer including a liquid crystal molecule kept between the first alignment film and the second alignment film,
the method comprising:
providing first anchoring strength to the first alignment film which is a photo-alignment film; and
providing second anchoring strength to the second alignment film which is a rubbing alignment film,
wherein the first anchoring strength is substantially equal to or greater than the second anchoring strength, and
equations (1) and (2) below are satisfied if A 1 =a 1 ×10^(−a 2 ), where A 1 is the first anchoring strength provided to the first alignment film,
0< a 2 ≦4 (1)
1≦ a 1 <10 (2).
7. The method of manufacturing a liquid crystal display of claim 6 , wherein
equations (3) and (4) below are satisfied if A 2 =b 1 ×10^(−b 2 ), where A 2 is the second anchoring strength provided to the second alignment film,
0< a 2 ≦b 2 ≦4 (3)
1≦ b 1 <10 (4).