LIQUID CRYSTAL DISPLAY DEVICE

• Main Authors: TASHIRO KUNIHIRO, HAYANO TAKAYUKI, NISHIWAKI SHOGO
• Format: Patent
• Language: English
• Published: 09.02.2012
• Subjects: DEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH ISMODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THEDEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY,COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g.SWITCHING, GATING, MODULATING OR DEMODULATING; FREQUENCY-CHANGING; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL LOGIC ELEMENTS; OPTICS; PHYSICS; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF

In a liquid crystal display device using pixel electrodes having a fishbone structure as well as using the PSA technology, the occurrence of an azimuthal angle shift in the vicinity of the pixel edge is suppressed. A liquid crystal display device according to the present invention is a liquid crystal display device comprising a plurality of pixels and a pair of polarizing plates located in crossed Nicols and providing display in a normally black mode. Each of the plurality of pixels includes a liquid crystal layer containing liquid crystal molecules having a negative dielectric anisotropy; a pixel electrode and a counter electrode facing each other with the liquid crystal layer interposed therebetween; a pair of vertical alignment films respectively provided between the pixel electrode and the liquid crystal layer and between the counter electrode and the liquid crystal layer; and a pair of alignment sustaining layers respectively provided on surfaces of the pair of vertical alignment films on the liquid crystal layer side and formed of a photopolymerizable material. The pixel electrode includes a cross-shaped trunk portion located so as to overlap polarization axes of the pair of polarizing plates, a plurality of branch portions extending from the trunk portion in a direction having an angle of about 45° with respect thereto, and a plurality of slits formed between the plurality of branch portions. The pixel electrode has an overall shape which is a generally parallelogram shape with four right angles, each of four sides of which has an angle of about 45° with respect to the polarization axes of the pair of polarizing plates. The plurality of branch portions are located generally symmetrically with respect to the trunk portion.