Eagleyard Photonics has released a directly modulated green laser source with an optical output power in excess of 20mW for mobile projection applications.
The result was achieved in close cooperation with companies and institutes all based in Berlin. The Ferdinand-Braun-Institut für Höchstfrequenztechnik (FBH) developed the special semiconductor laser chip, the Fraunhofer Institut für Zuverlässigkeit und Mikrointegration (IZM) was responsible for the assembly of the demonstrator module and Luceo Technologies GmbH developed a dedicated laser driver to supply modulated high currents to the laser diode. The project was initiated by Eagleyard Photonics and the green laser is one key component for projection displays in mobile phones, PDAs and game consoles.
The design is based on a gallium arsenide laser diode, emitting non-visible infrared laser radiation, and a frequency doubling crystal that converts the infrared light directly into visible green. Apart from the laser chip and the doubling crystal, no additional optical elements are required. The key element of the optical engine is the semiconductor chip with its high output power, developed by FBH. The special design allows for direct modulation at video rates, a stable wavelength to match the doubling crystal and high output power for efficient projection brightness.
The Fraunhofer IZM developed and assembled the demonstrator in order to create a usable testbed for the green laser module. On the basis of thermo-mechanical simulations, the packaging concept was designed to maintain sub-micron accuracy during both assembly and operation. Luceo Technologies developed and delivered the high power laser driver, capable of data rates up to 450MBit/s and modulated currents up to 1.5A. Eagleyard was thus able to successfully characterize and optimize the laser source and prove its capability for laser projection applications.