At present, projector technology is generally based on LEDs. They save power but have the disadvantage that they do not generate bright images. A green laser developed by a Berlin-based consortium headed by eagleyard Photonics GmbH will take the use of much brighter laser light in the field of mobile microprojectors a good step further. Corning in the USA is also working on a green laser. 

The concept is based on a gallium arsenide laser diode, whose infrared emission is converted into visible green light by a frequency-doubling crystal. A laser chip developed at Ferdinand-Braun-Institut für Höchstfrequenztechnik (FBH), which has a wavelength adjusted precisely to the crystal, enables modulation with data rates of up to 450 Mbps. No more elements are required. eagleyard believes that the concept is suitable for miniaturization and subsequent low-cost production.

The heart of the innovation is a laser chip developed by FBH. The special design allows modulation with video data rates and guarantees a precise wavelength adjusted to the crystal. The laser also provides the very high output needed to achieve efficient projector brightness.

Prototypes of microprojectors based on this innovative concept have been around since 2007. The market launch of mobile devices equipped with this technology, such as cell phones and PDAs, is scheduled for 2009.

A similar approach is being taken in the USA. US company Corning is currently developing miniaturized green laser diodes. According to Corning, these are brighter than the red diodes that have been tried out before. With a projector volume of just one cubic centimeter it is possible to generate ten to 20 lumens and project a picture diagonal of nine to twelve inches with these new diodes.