Patent ID: 9575364
Date: 2017-02-21
CPC Classifications: G02F

Claim:
1. A liquid crystal display device comprising: a vertical alignment liquid crystal layer; a first substrate and a second substrate which face each other with the liquid crystal layer between them; a first electrode and a second electrode on the first and the second substrates, respectively, to face the liquid crystal layer; two photo-alignment films between the first electrode and the liquid crystal layer and between the second electrode and the liquid crystal layer, respectively; and a plurality of pixel regions in a matrix pattern between the first and the second substrates, wherein each of the plurality of pixel regions includes a first liquid crystal domain, of which a reference alignment direction defined by the two photo-alignment films is a first direction, and a second liquid crystal domain, of which the reference alignment direction is a second direction that is different from the first direction, the first electrode has a slit cut region, through which a slit has been cut substantially parallel to the reference alignment direction defined by the two photo-alignment films, in a part of a region which is allocated to each of the first and the second liquid crystal domains, a width of the slit is set so that when a highest grayscale voltage is applied to the first electrode, an effective voltage applied to the liquid crystal layer over the slit decreases by at least 0.5 V and an alignment direction of liquid crystal molecules in the liquid crystal layer over the slit shifts with respect to the reference alignment direction by less than 45 degrees, each of the plurality of pixel regions further includes a third liquid crystal domain and a fourth liquid crystal domain, of which the reference alignment directions are a third direction and a fourth direction, respectively, the first direction, the second direction, the third direction, and the fourth direction are four directions which are defined so that an angle formed between any two of the four directions is approximately equal to an integral multiple of 90 degrees, the first electrode also includes the slit cut region in a portion of the region which is allocated to each of the third liquid crystal domain and the fourth liquid crystal domain, the first liquid crystal domain, the second liquid crystal domain, the third liquid crystal domain, and the fourth liquid crystal domain are in two columns and two rows in a matrix pattern so that each of the first liquid crystal domain, the second liquid crystal domain, the third liquid crystal domain, and the fourth liquid crystal domain is adjacent to each of others of the first liquid crystal domain, the second liquid crystal domain, the third liquid crystal domain, and the fourth liquid crystal domain, a portion of a plurality of edges of the first electrode located adjacent to the first liquid crystal domain includes no edge portion in which an azimuthal direction that is perpendicular to the portion of the plurality of edges of the first electrode located adjacent to the first liquid crystal domain and that points toward an inside of the first electrode defines an angle greater than 90 degrees with the first direction, a portion of a plurality of edges of the first electrode located adjacent to the second liquid crystal domain includes no edge portion in which an azimthal direction that is perpendicular to the portion of the plurality of the edges of the first electrode located adjacent to the second liquid crystal domain and that points toward the inside of the first electrode defines an angle greater that 90 degrees to the second direction, a portion of a plurality of edges of the first electrode located close to the third liquid crystal domain includes no edge portion in which an azimuthal direction that is perpendicular to the portion of the plurality of the edges of the first electrode located close the third liquid crystal domain and that points toward the inside of the first electrode defines an angle greater than 90 degrees with the third direction, and a portion of a plurality of edges of the first electrode located adjacent to the fourth liquid crystal domain includes no edge portion in which an azimuthal direction that is perpendicular to the portion of the plurality of the edges of the first electrode located adjacent to the fourth liquid crystal domain and that points toward the inside of the first electrode defines an angle greater that 90 degrees with the fourth direction.