Cell Phone Transforms With TFT Technology

Today's cellular handsets house an impressive array of features. These features range from voice communication, e-mail, and pager-like text messaging to games and Web-enabled microbrowsers. Generally, these capabilities are adaptations of current software applications. The increasing popularity of integrated digital cameras may mark a departure from this strategy, however. It may even begin to change the way that people think about mobile phones.

Sharp Corp. is actively driving this change in thought process. The company recently combined its extensive knowledge of display technology with its Flash memory, camera, and user-interface technologies. This work spawned a number of impressive camera-enabled mobile phones. The most recent of these phones is the GSM-based, GPRS-supported GX-10 handset (see figure).

Originally, Sharp brought its camera phones to Japan, where they operated on the PDC network. In contrast, the GX-10 mobile phone is the company's first device to operate on the GSM/GPRS networks used extensively throughout Europe, Asia, and North America.

The GX-10 clamshell-style handset boasts a 2-in., high-resolution liquid-crystal display (LCD) of 65,536 colors. Because it incorporates a digital still camera, users can now take, view, and send high-quality images via the Multimedia Messaging Service (MMS). This service sends messages from one handset to another. The messages themselves can include any combination of text, sound, or color image.

As for the design of this multi-featured phone, the camera is placed on the outside of the handset case. It sits behind the main LCD. Aside from being easy to access, the camera claims to be easy to operate. Using the GX-10 phone, the user simply takes a picture with the handset in the same way that one would snap a photo with a conventional camera.

This 110-Kpixel digital camera is equipped with five exposure levels and a two-stage digital zoom. It can store up to 80 digital pictures. Downloading pictures from the GX-10 to a personal computer can be accomplished via an infrared (IR) port or a USB connection.

At the core of the display is Sharp's proprietary LCD Advanced (Transflective) Thin Film Transistor (TFT) technology. With the transflective screen, users can view even the smallest images clearly—regardless of whether they are in bright sunlight or a dark tunnel. To accomplish this feat, the screen maximizes the transmissivity and contrast ratio between the reflective and transmissive modes.

The GX-10 GSM/GPRS mobile camera phone also incorporates technologies from a variety of other companies. For example, TTPCom (www.ttpcom.com) provided the main GSM/GPRS platform for the GX-10. Analog Devices, Inc. (www.analog.com) supplied its signal-processing products. Examples include ADI's SoftFone GSM/GPRS wireless chip set, LCD control, and power-management technologies.

Though this product puts a lot of emphasis on digital imaging, Sharp also recognizes the growing consumer interest in distinctive sounds. As a result, the GX-10 comes equipped with 16-chord polyphonic ringtones. These are multiple tones that are used together instead of as a series of dull single tones. ADI's SoftFone technology provides these ringtones. In the process, it also saves battery life and valuable chip space. These advantages stem from SoftFone's use of software to replace hardware-decoding and mixing chips.

Other features of the GX-10 handset include a Wireless Application Protocol (WAP) microbrowser for Internet surfing and support for Short Message Service (SMS). Additionally, the GX-10 is a Java-enabled handset that allows for the downloading of games and other applications. With predictive T9 text-conversion technology, users can input e-mail quickly and easily. The term "T9" refers to software that predicts commonly used words with just one key press per letter.

The GX-10 mobile camera phone is just one of several handsets to feature Sharp's display technologies. Japan's NTT DoCoMo has recently introduced the Mova SH251iS mobile phone. It supports a Sharp 3D color LCD. Using a transflective TFT display, the Sharp SH251iS comes equipped with a 3D editor function that enables users to convert 2D images into 3D images that are viewable by the naked eye. This 3D effect is created by projecting different images to the right and left eyes. Essentially, it tricks the viewer's brain into perceiving depth in the image.

The Sharp GX-10 measures 27 × 94 × 49 mm when folded. It weighs a mere 100 g. The handset is available now.