Optoelectronic engineers from the universities of Hong Kong and Shanghai have succeeded in creating a special liquid crystal display (LCD) which is paper-thin, flexible, light, durable and very inexpensive at about 5 dollars for a 5-inch screen, or roughly 12.7 centimeters. With this futuristic electronic “sheet”, a daily newspaper could be uploaded and updated in real time several times during the day, and allows for many other possible applications.
The researchers demonstrated the results of their work in the scientific journal Applied Physics Letters. As with conventional displays, the new LCD is also structured like a “sandwich” of two very thin plates which are filled with liquid crystals. The difference from conventional displays lies, however, in the absence of electrical circuits. In the new rewritable LCD, the external walls guarantee light polarization through complex physical processes, and therefore reduce its bulk, eliminate the need for electrodes and an electrical source connection, except for the initial powering on.
Another significant difference between the new ultrathin display and prior LCDs is the presence of a series of mesh spacers which allow the two “sandwiched” layers to be kept separated even when the sheet is bent, keeping the liquid crystal contents from moving excessively.
Finally, the Chinese scientists were able to insert a special type of liquid crystal which reflects the primary colors of red, blue and green into the ultra-thin LCD. This is in contrast to other, less advanced, rewritable LCDs which are able to simultaneously display only two colors. A long time will be necessary, however, for ultra-thin “full color” screens, since the researchers assert they would need to use pixels which are too small for the human eye to see.
