The market for thin-glass touch panels in cell phones is particularly promising in China. Due to the large number of Chinese characters, it takes a lot of effort to write a text message using conventional keypads with just 12 keys.
Touch panels are better suited since the messages can be entered using a pen backed by character recognition software. SCHOTT borosilicate thin glass, such as D 263 T or AF 45 (alkali-free), is ideal for such applications. D 263 T can be manufactured in thicknesses of 0.03 to 1.1 mm and AF 45 in thicknesses of 0.05 to 0.5 mm.
Both types are produced using the down-draw process and feature a high luminous transmittance, as well as excellent chemical, thermal, and surface properties. Thanks to their flatness, both glass types can easily be further processed or cut to size using laser or diamond tools. Robust touch panels using D 263 T are already on the market in car navigation systems. As opposed to film type touch panels, these products meet the high demands of the automotive industry with regard to both temperature and humidity resistance a well as life expectancy.
D 263 T is also proven as a cover glass for opto-couplers in laser diodes, as found in CD players, and for temperature and humidity sensors in air conditioning. Both glass types play a major role in the expanding market for camera phones: D 263 T and AF 45 are used for packaging CCD (charge coupled device) and CMOS (complementary metal oxide semiconductor) image sensors, while AF 45 is used in the WLCSP (wafer level chip size packaging) process. This technology enables image sensors to be packaged in miniature format (5 x 5 mm) and thus their use in cell phones.
This is one of the smallest possible packaging formats currently available on the mass market for camera phones. A further application for D 263 T is as IR-cut filters, one of the components in the camera modules found in mobile phones. "SCHOTT markets both of these thin glass product ranges via its sales offices all around the world, including SCHOTT Taiwan," explains Maida Claassen, Product Manager at the Group subsidiary SCHOTT Spezialglas AG, located in Grünenplan, Germany. “We've been exporting our thin glass products to Asia for the past 15 years – which is now our main market,” Claassen continues. “In addition to producing extremely thin glass, we can also cut it to our customers’ desired format. We are focusing on glass thickness of 0.55 mm and less, for which there is an ever-increasing demand.”