Photo alignment technology improves lcd display
1 min read
Sharp Microelectronics Europe has introduced a newly developed UV2A technology which it says will result in superior picture performance of lcds.
The technology has been designed for an ultraviolet-induced multi domain vertical alignment of liquid crystal molecules and is based on combining proprietary materials with UV exposure equipment and processing technologies.
The UV2A technology resembles a complex structure on the panel glass, provoking the alignment of the lc molecules. The micro structure comes from a special polymer film - the alignment layer - the panel glass is coated with. The polymer chains standing out of the film surface are aligned by a photometric method to form micro ribs, whereas the predefined tilt angle of the ribs corresponds with the direction of the uv light inducing the alignment of the polymer chains.
This ribbed microstructure is said to provide a precise control over the alignment of liquid crystal molecules. And, according to Sharp, the tilt angle of liquid crystal molecules, which are around two nanometres in size, can be determined with accuracy in the range of picometers.
Sharp says that the alignment of the liquid crystals by applying the UV2A technology has two effects. Firstly, it almost completely eliminates light leakage from the backlight and raises the static contrast ratio to 5000:1. This makes it possible to display extremely deep blacks.
Secondly, the technology enables higher aperture ratios in the lcd panel, apparently increasing light transmission by around 20%. This enables more efficient use of light from the backlight and saves energy while displaying bright, vivid colours.
