1. Field of the Invention
The present invention relates to a segment display-type liquid crystal display apparatus.
2. Description of the Background Art
A liquid crystal display apparatus is broadly used as an information display unit in various electronic devices for consumer or automobile use. In General, a liquid crystal display apparatus is configured by disposing a liquid crystal layer made of a liquid crystal material between two substrates that are placed opposite each other with a gap of roughly several micrometers. To obtain favorable viewing angle dependency even when voltage is applied in such a liquid crystal display apparatus, it is effective to use a multi-domain orientation which ensures that the orientation direction of the liquid crystal molecules will be separated into a plurality of directions in a single pixel.
With regard to multi-domain orientation techniques, Japanese Patent No. 4107978 (Patent Document 1), for example, discloses a technique for realizing a multi-domain orientation that comprises two orientation directions by generating two diagonal electric fields in directions that differ from each other by 180° inside the liquid crystal layer by providing a plurality of openings to the electrodes, and orientating the liquid crystal molecules along such electric field directions. Further, for example, Japanese Patent No. 4846402 (Patent Document 2) and Japanese Patent No. 4884176 (Patent Document 3) disclose techniques for realizing a multi-domain orientation that comprises four orientation directions by refining the shapes of a plurality of openings provided to the electrodes. Furthermore, for example, Chinese Unexamined Patent Application Publication No. 101477280 (Patent Document 4) and Japanese Unexamined Patent Application Publication No. 2012-63711 (Patent Document 5) also disclose orientation control techniques for orientating liquid crystal molecules in all directions without limiting the orientation directions to a distinct plurality of directions by refining the shapes of a plurality of openings. In each of these orientation control techniques, the plurality of openings provided to the electrodes in order to control the electrical field directions serves as a critical technical element.
However, in a liquid crystal display apparatus that executes a display (a so-called reverse display) which facilitates visual recognition of a pattern section by changing the transmittance in the vicinity of the pattern displayed, due to the complexity of the pattern, there are locations where the width of a section that separates sections (outline patterns) in which the electrodes are open in accordance with the pattern becomes narrow. For example, such a location may occur in a case where characters that make up a complex kanjis (Chinese characters used in Japanese writing) serve as the pattern. If such a plurality of openings as described above is provided to electrodes having such a plurality of outline patterns, an opening may cut across a section that separates outline patterns, thereby causing disconnection in the electrode and, as a result, display flaws. While, in response, the longitudinal-direction length of the respective openings may conceivably be set smaller than the width of the section that separates the outline patterns, in a case where the difference between the longitudinal-direction length and the width of the section that separates the outline patterns is not significantly large, the same inconvenience occurs due to the formation precision of etching and the like.
On the other hand, while the problem may also be conceivably resolved by dividing the outline patterns between one electrode and the other electrode in a well-balanced manner, in such a case, high accuracy is required in the positioning of the electrodes to ensure that the pattern displayed is not destroyed, making it difficult for such a technique to serve as a realistic solution in consideration of manufacturing yield and the like.
USPTO Backgrounds
USPTO Backgrounds