The Ar-ion lasers was traditionally used as light source in many applications related to printing and reprographics processes. Over the last decade, the gas lasers have generally been replaced by solid-state alternatives, in the RGB colours, in the UV or in the IR. RGB lasers, mainly at relatively low powers, are being used in laser recorders for digital photofinishing, where digitally stored images are printed on photo paper and in laser scanners for transfer of analogue film images to digital format. 473 nm and 532 nm are typically used wavelengths for the blue and green colours. Ultra-high power stability and low noise are important requirements on the lasers. Some advanced photofinishing applications require also higher power levels.

Ever since the advent of visible lasers they have been considered as highly attractive light sources for RGB projection display applications. The spectral purity, high brightness and unmatched beam confinement of laser devices result in better colour saturation, better contrast, larger screen sizes and improved power efficiency than what can be achieved with CRTs, LEDs or arc lamps.

Several modulation and scanning technologies have been proposed and used for laser-based projection displays; progressive scan, line-scan using an array of diffraction elements or 2D scan using micro display devices such as DMD or LCoS chips.

Laser displays may soon provide a competitive alternative in the markets for large screen HDTVs and Digital Cinema. Lasers are also attractive for us in ultra-compact hand-held projector devices, so called picobeamers.

Cobolt’s DPSS lasers in the blue and green have proven to be very suitable for use in several types of laser display devices. Cobolt has also developed a unique microbench technology for ultra cost-efficient, compact and alignment free assembly of high power DPSSL arrays.