Liquid crystal display device
View Patent ↗According to one embodiment, a liquid crystal display device includes a first substrate unit, a second substrate unit, and a liquid crystal layer. The first substrate unit includes a first pixel electrode and a second pixel electrode. The second pixel electrode is adjacent to the first pixel electrode in the first direction. The second pixel electrode is light-reflective. The second substrate unit includes a counter electrode. The counter electrode is light-transmissive. The liquid crystal layer is provided between the first substrate unit and the second substrate unit. The first pixel electrode includes a first electrode portion and a second electrode portion. The first electrode portion is light-reflective. At least a portion of the second electrode portion is provided between the first electrode portion and the second pixel electrode. A light reflectance of the second electrode portion is lower than a light reflectance of the first electrode portion.
1. A liquid crystal display device, comprising:
a first substrate unit having a first major surface, the first substrate unit including
a first pixel electrode disposed in the first major surface, and
a second pixel electrode disposed in the first major surface and arranged with the first pixel electrode to be adjacent to the first pixel electrode in the first direction, the second pixel electrode being light-reflective;
a second substrate unit having a second major surface opposing the first major surface, the second substrate unit including a counter electrode provided in the second major surface, the counter electrode being light-transmissive; and
a liquid crystal layer provided between the first major surface and the second major surface,
the first pixel electrode including:
a first electrode portion, the first electrode portion being light-reflective; and
a second electrode portion, at least a portion of the second electrode portion being provided between the first electrode portion and the second pixel electrode,
a light reflectance of the second electrode portion being lower than a light reflectance of the first electrode portion,
the second pixel electrode being light-reflective and not having any portion that is light-transmissive,
a light transmittance of the second electrode portion being higher than the light reflectance of the second electrode portion and higher than a light absorptance of the second electrode portion,
wherein the second electrode portion includes a region not overlapping the first electrode portion in a direction from the first substrate unit toward the second substrate unit,
a length of the region in the first direction is shorter than a length of the first electrode portion in the first direction and is shorter than a length of the second pixel electrode in the first direction,
the first substrate unit includes a first switching element and a second switching element, the first switching element is electrically connected to the first pixel electrode, the second switching element is electrically connected to the second pixel electrode,
the first pixel electrode is set to a potential having a first polarity having the counter electrode as a reference, and
the second pixel electrode is set to a potential having a second polarity having the counter electrode as the reference, the second polarity being different from the first polarity.
2. The device according to claim 1 , wherein
the first electrode portion has, when projected onto the first major surface,
a first side, and
a second side separated from the first side and provided between the first side and the second pixel electrode, and
the second electrode portion includes a first portion contacting the second side when projected onto the first major surface.
3. The device according to claim 2 , wherein the second electrode portion further includes a second portion covering at least the first side of the first electrode portion.
4. The device according to claim 2 , wherein the second electrode portion further includes a third portion interposed between the first major surface and the first electrode portion.
5. The device according to claim 1 , wherein
the first substrate unit further includes:
a first substrate, the first substrate being light-transmissive;
a first interconnect electrically connected to the first switching element, and
at least a portion of the first interconnect is positioned between the first electrode portion and the first substrate.
6. The device according to claim 1 , wherein
the liquid crystal layer includes:
a first liquid crystal portion;
a second liquid crystal portion provided between the first liquid crystal portion and the second major surface; and
a third liquid crystal portion provided between the first liquid crystal portion and the second liquid crystal portion,
a long-axis direction of the liquid crystal of the first liquid crystal portion is a first alignment direction, and
the first alignment direction intersects a second direction, the second direction being parallel to the first major surface and perpendicular to the first direction.
7. The device according to claim 6 , wherein a component of the first alignment direction parallel to the first direction is larger than a component of the first alignment direction parallel to the second direction.
8. The device according to claim 6 , wherein an angle between the first alignment direction and the first direction is not less than 140 degrees and not more than 180 degrees.
9. The device according to claim 6 , wherein
a long-axis direction of the liquid crystal layer of the second liquid crystal portion is a second alignment direction, and
an angle between the first alignment direction and the second alignment direction is not less than 60 degrees and not more than 80 degrees.
10. The device according to claim 1 , further comprising an optical layer,
the second substrate unit being provided between the liquid crystal layer and the optical layer,
an intensity of scattered light of the optical layer for light incident on the optical layer from a first incident direction is different from an intensity of scattered light of the optical layer for light incident on the optical layer from a second incident direction,
an alignment of a direction component of the first incident direction in a plane parallel to the first major surface is different from a direction component of the second incident direction in the plane.
11. The device according to claim 10 , wherein
the optical layer includes a plurality of first optical units and a second optical unit, the first optical units being light-transmissive and disposed in the plane, the second optical unit being light-transmissive and provided between two of the first optical units, a refractive index of the second optical unit being different from a refractive index of the first optical units, and
a boundary between the first optical unit and the second optical unit is tilted with respect to the plane.
12. The device according to claim 1 , wherein the first electrode portion and the second pixel electrode are specular.