Hitachi Develops 4096-color Electronic Paper Display
Hitachi, Ltd. has developed a 4096-color electronic paper display. An "RGBW type" color filter that includes W (white) in addition to the three colors of RGB was used to enable color reproduction. The display size and the pixel count are 13.1 inches and 512 x 384, respectively. In May 2006, the company launched "Albirey," a general purpose display using an electronic paper. It was a 13.1-inch monochrome display with the pixel count of 1024 x 768. The latest development has enabled the color representation while maintaining the display size. The use of the color filter reduced the pixel count by half in both vertical and horizontal directions.
As with the previous product, the latest electronic paper was manufactured by Bridgestone Corp. Bridgestone showcased a 4096-color electronic paper using a color filter at "SID 2006" held in June 2006. It was, however, an 8.1-inch display with the pixel count of 480 x 384. Hitachi explains that the electronic paper employed in the newly developed display boasts a larger size and a greater number of pixels. In addition, a Hitachi spokesperson claimed that "the contrast ratio and reflectivity have further improved compared to the product demonstrated at the SID event." Specific values of the contrast ratio and reflectivity are not to be disclosed.
Along with its monochrome display already on the market, Hitachi intends to launch the color display within 2007. "With further improvement in reflectivity for brighter display, this product will meet the display performance requirements for commercialization," said the spokesperson.