Liquid crystal display device
View Patent ↗A new type of liquid crystal display (LCD) device with improved high transmittance and wide-view-angle characteristics while without gray-level inversion at an inclined viewing angle is provided. The LCD device includes a first substrate with common electrodes, a second substrate with at least one pixel unit, a liquid crystal (LC) layer disposed between the first substrate and the second substrate, a first polarizer, and a second polarizer. The pixel unit has a pixel electrode, which is formed by at least one dense electrode area and at least one sparse electrode area. The LC molecules of the LC layer form a continuous-domain alignment after being driven by a voltage.
1. A liquid crystal display (LCD) device, at least having a display area, comprising:
a first substrate with a common electrode;
a second substrate with at least one pixel unit, wherein the pixel unit has a pixel electrode, wherein the pixel electrode comprises a plurality of trunk electrodes, a plurality of branch electrodes and a plurality of sub-branch electrodes, parts of the branch electrodes are connected to one of the trunk electrodes, and parts of the sub-branch electrodes are connected to one of the branch electrodes;
a liquid crystal (LC) layer, disposed between the first substrate and the second substrate, wherein after being driven by a voltage, the LC molecules of the LC layer form a continuous-domain alignment;
a first polarizer, disposed above the first substrate; and
a second polarizer, disposed below the second substrate and having a polarization axis perpendicular to a polarization axis of the first polarizer,
wherein the LC layer is doped with chiral dopants and selects optimal Δnd and d/p parameters, so that as α is at any angle, the transmittance T is always greater than a minimal transmittance T min , where Δn is a birefringence of the LC material, d is a thickness of the LC layer, p is a pitch of the chiral dopants, α is defined to be an angle included between an alignment direction of LC molecules in the middle LC layer and a polarization axis of one polarizer.
2. The LCD device according to claim 1 , wherein the LC layer adopts a vertically aligned n-type LC material doped with chiral dopants or a vertically aligned negative dielectric anisotropy LC material.
3. The LCD device according to claim 1 , wherein the electrode gap widths between the branch electrodes are different from the electrode gap widths of the sub-branch electrodes.
4. The LCD device according to claim 3 , wherein the electrode widths or the electrode gap widths of the branch electrodes have equal intervals.
5. The LCD device according to claim 3 , wherein the electrode width of each branch electrodes is between 1 μm and 5 μm.
6. The LCD device according to claim 3 , wherein the branch electrodes are branched from the trunk electrodes at any angle, and the sub-branch electrodes are branched form the branch electrodes at any angle.
7. The LCD device according to claim 6 , wherein the angles between the trunk electrodes and the branch electrodes are different from the angles between the branch electrodes and the sub-branch electrodes.
8. The LCD device according to claim 1 , wherein the sub-branch electrodes surround an outer periphery of the trunk electrodes.
9. The LCD device according to claim 1 , wherein the sub-branch electrodes surround an outer periphery of the branch electrodes.