Transflective liquid crystal display using separate transmissive and reflective liquid crystal cells and materials with single cell gap
View Patent ↗A transflective liquid crystal display (TLCD) using separate transmissive (T) and reflective (R) cells in which two liquid crystal materials with different birefringence changes are used. The birefringence change of the R region is half of the birefringence change of the T region. In this case, a single cell gap is possible and identical transmittance and reflectance for R and T is obtained. It is applicable to various reflective LC modes, and the fabrication methods are simple.
1. A method of improving a transflective liquid crystal display (TLCD) comprising the steps of:
providing a liquid crystal area structure having a transmissive portion and a reflective portion in the liquid crystal area of the transflective LCD comprising the steps of:
fabricating a serpentine wall on a transparent substrate;
sealing the serpentine wall to the substrate to form independent transmissive and reflective regions having an equal cell gap;
filling the transmissive portion with a first liquid crystal material;
filling the reflective portion with a second liquid crystal material, a birefringence of the second liquid crystal material being one-half a birefringence of the first liquid crystal material in the transmissive portion; and
passing backlight and ambient light through the TLCD to achieve identical transmittance and reflectance displaying high quality images.
2. The TLCD of claim 1 , further including:
a single quarter-wave (λ/4) film and a top polarizer layer and a bottom polarizer layer.
3. The TLCD of claim 1 , further including;
a quarter-wave (λ/4) film adjacent to a top polarizer layer and a quarter-wave (λ/4) film adjacent to a bottom polarizer layer.
4. The method of claim 1 , wherein the first and second liquid crystal materials are a mixed-mode twisted nematic (MIN) cell.
5. The method of claim 1 , wherein the first and second liquid crystal materials are a homogeneous liquid crystal with quarter wave phase (λ/4) retardation.
6. The method of claim 1 , wherein the first and second liquid crystal materials are a vertically aligned liquid crystal with quarter wave (λ/4) phase retardation.