Liquid crystal display device
View Patent ↗A high-definition and high-contrast liquid crystal display device having a high aperture ratio without light leakage around a columnar spacer is provided. The liquid crystal display device of a horizontal electric field type includes a TFT substrate with a pixel electrode and a common electrode, a color filter substrate with a color filter, a columnar spacer interposed between the substrates, and a liquid crystal layer arranged between the substrates. A liquid crystal alignment film formed between the substrates is a photo-alignment film. The columnar spacer, formed on the color filter substrate or the TFT substrate, has a wall-like shape and an inclined surface extending in a direction parallel to or perpendicular to a direction in which the liquid crystal is initially aligned.
1. A liquid crystal display device of a horizontal electric field type, comprising:
a TFT substrate having a pixel electrode, and a common electrode facing the pixel electrode through an insulating film, a first photo aligned alignment film covering the surface of the TFT substrate;
an opposing substrate facing the TFT substrate and having a second photo aligned alignment film covering a surface of the opposing substrate;
a spacer arranged on the opposing substrate; and
a liquid crystal layer arranged between the first photo aligned alignment film and the second photo aligned alignment film,
wherein a liquid crystal of the liquid crystal layer is initially aligned at an inclined angle by a predetermined bias angle with respect to a direction in which the pixel electrode extends, in a plan view,
wherein a top surface of the spacer having an one side which is arranged along a direction parallel to or perpendicular to a direction of the predetermined bias angle, in a plan view,
wherein a side surface of the spacer corresponding to the one side is arranged along a direction parallel to or perpendicular to a direction of the predetermined bias angle,
wherein the side surface is inclined with respect to the opposing substrate in a range of 60 to 80 degrees,
wherein the first photo aligned alignment film and the second photo aligned alignment film are alignment-processed by the irradiation with a polarized light, and
wherein the side surface reflects the polarized light.
2. The liquid crystal display device according to claim 1 , wherein
in a plan view, the spacer has a quadrangular-column shape with a substantially quadrilateral top surface, and
each of four end sides of the substantially quadrilateral top portion of the spacer extend in a direction nearly parallel to or nearly perpendicular to the direction in which the liquid crystal is initially aligned.
3. The liquid crystal display device according to claim 1 , further comprising:
a first black matrix portion extending in a first direction and a second black matrix portion extending in a second direction,
wherein the spacer is arranged at an intersection of the first black matrix portion and the second black matrix portion.
4. The liquid crystal display device according to claim 1 , wherein
a viewing angle is compensated for by different pixels,
a first black matrix portion extending in a first direction and a second black matrix portion extending in a second direction,
the top surface of the spacer has curved corners at four corners, in a plan view, and
one of the curved corners is arranged at an intersection of the first black matrix portion and the second black matrix portion.
5. The liquid crystal display device according to claim 1 , wherein
a viewing angle is compensated for by adjacent two pixels,
a first black matrix portion extending in a first direction and a second black matrix portion extending in a second direction,
the top surface of the spacer has curved corners at four corners, in a plan view, and
one of the curved corners is arranged at an intersection of the first black matrix portion and the second black matrix portion.
6. The liquid crystal display device according to claim 1 , wherein
the top surface of the spacer has curved corners at four corners, in a plan view,
a first black matrix portion and a second black matrix portion extending in a first direction and a third black matrix portion extending in a second direction,
one of the curved corners is arranged at an intersection of the first black matrix portion and the third black matrix portion,
another of the curved corners is arranged at an intersection of the second black matrix portion and the third black matrix portion.
7. The liquid crystal display device according to claim 3 , wherein
the spacer has a quadrangular-column shape with a substantially quadrilateral top surface, in a plan view, and
the spacer extends in a direction different from the first direction and the second direction.
8. The liquid crystal display device according to claim 1 , further comprising:
a plurality of drain lines,
the plurality of drain lines are not parallel to or perpendicular to the one side or the direction in which the liquid crystal is initially aligned.
9. The liquid crystal display device according to claim 1 , wherein
the direction in which the liquid crystal is initially aligned is parallel to the TFT substrate and the opposing substrate.
10. The liquid crystal display device according to claim 1 , wherein
the side surface of the spacer is formed along a direction in which a polarized light doesn't change its polarization axis when reflected at the side surface.
11. The liquid crystal display device according to claim 1 , wherein
the spacer is arranged along a direction parallel to or perpendicular to a polarization direction of a polarized light.
12. A liquid crystal display device of a horizontal electric field type, comprising:
a TFT substrate having a first photo aligned alignment film covering the surface of the TFT substrate;
an opposing substrate facing the TFT substrate and having a first black matrix portion and a second black matrix portion extending in a first direction, a third black matrix portion extending in a second direction cross the first direction, and a second photo aligned alignment film covering a surface of the opposing substrate;
a spacer arranged on the opposing substrate; and
a liquid crystal layer arranged between the TFT substrate and the opposing substrate,
wherein the first photo aligned alignment film and the second photo aligned alignment film are alignment-processed by the irradiation with a polarized light,
the spacer is arranged on the first black matrix portion, the second black matrix portion, and the third black matrix portion,
a top surface of the spacer has four corners, in a plan view,
two corners of the four corners are arranged at an intersection of the first black matrix portion and the third black matrix portion,
another two corners of the four corners are arranged at an intersection of the second black matrix portion and the third black matrix portion, and
the top surface of the spacer has two long sides extending parallel to the third black matrix portion.
13. The liquid crystal display device according to claim 12 , wherein
the spacer has two side surfaces corresponding to the two long sides, and
the two side surfaces are inclined with respect to the opposing substrate in a range of 60 to 80 degrees.
14. The liquid crystal display device according to claim 13 , wherein
the two side surfaces reflect the polarized light.
15. The liquid crystal display device according to claim 14 , wherein
the two side surfaces are formed so as not to change a polarization axis of the polarized light when the polarized light is reflected at the two side surfaces.