Reflective liquid crystal display of twisted nematic mode with high reflectance ratio

摘要

A reflective liquid crystal display device includes: first and second substrates spaced apart and facing each other; a twisted nematic liquid crystal layer sandwiched between the two substrates, the liquid crystal layer having a twist angle and birefringence property &Dgr;n and having a thickness d; a retardation film disposed on the first substrate and opposite to the liquid crystal layer, the film converting a first linearly polarized light from above to a first circularly polarized light and converting a second circularly polarized light reflected from below to a second linearly polarized light; a linear polarizer disposed on the retardation film and opposite to the liquid crystal layer and converting the incident light to the first linearly polarized light; and a reflector disposed between the liquid crystal layer and the second substrate and reflecting light passed through the liquid crystal layer. A most desirable range for the twist angle is between above 65° and 75° or 75° and 85° and a most desirable range of a product d&Dgr;n is between about 0.20 &mgr;m and 0.28 &mgr;m or 0.18 &mgr;m and 0.26 &mgr;m. By the invention, light reflectance, contrast ratio and yield can be enhanced.