Finance has come from the venture capital arms of both conglomerates, and the venture will build on quantum dot laser research carried out by Fujitsu and the University of Tokyo. It will have starting capital of just over $300 million.

The companies say they will invest in the venture in incremens, with Fujitsu initially taking a 61 percent stake in the venture and Mitsui holding 39 percent through their respective venture funds.

Quantum dots are semiconductor particles that are a single nanometer (one billionth of a meter) in size.

Quantum dot lasers produce a more stable output than conventional semiconductor lasers because they are much less affected by temperature variations. As a result, they produce fewer errors when used for data communications or in optical disk drives.

This guaranteed stability enables them to squeeze more bandwidth out of existing optical fibre lines, or to store more data on optical disk drives. The lasers also waste less energy, and have lower power consumption.

Next-generation blue laser technology, such as that employed in the Blu-ray optical disk used in Sony's forthcoming PlayStation 3 games console, is based on early quantum dot research.

The devices are also expected to play a key role as light sources for future optical communications equipment.