Philips Electronics NV is trying to squeeze the size of a CD drive and fit it into portable devices such as mobile phones, PDAs (personal digital assistants) and digital still cameras. Using blue laser technology, the company has managed to miniaturize a drive for a 3-centimeter-in-diameter optical disc that can store up to a gigabyte of data, it said Tuesday.

The Amsterdam-based company demonstrated what it claims to be the world's first fully functional prototype 5.6 centimeter by 3.4 centimeter by 0.75 centimeter optical drive by replaying audio data on a 3 centimeter optical disc, according to Philips.

The data capacity of the disc is 1.5 times more than that offered by current CD-ROMs, said Koen Joosse, a Philips spokesman. It was made possible using a blue laser, which has a shorter wavelength than red laser technology used in the current optical disc technology. A shorter wavelength means that the laser beam can create smaller dots on optical discs, which means more data can fit on them.

By comparison with flash storage media, which are used for conventional mobile devices such as digital still cameras, mobile phones and PDAs, CDs currently cost less. Therefore, Philips hopes the small discs will be widely distributed as portable prerecording and rewritable media, at lower cost than flash media, Joosse said.

However, "There is a number of challenges to get optical discs into small devices," said Wolfgang Schlichting, a research manager of removal storage at IDC.

The three main points that need to be dealt with are:

-- Optical drives are still costly to install in handheld devices.

-- The physical size of the optical drives, which have to be larger than the discs themselves, is inconvenient in comparison with flash memory cards.

-- As optical discs are rotating media, they consume more power than flash media.

"The technology is still at an early stage and we cannot determine when this will be commercialized," Philips' Joosse said. The company hopes to shrink the 0.75-centimeter height of the drive, while the three-centimeter-diameter for an optical disc is now small enough for mobile devices, he said.