Laser Sources for Projection Markets
Unfortunately, with regard to projector lighting there are always issues with scaling due to the low wattage required to power the lamp. Normally, projectors use around 200W of power for projecting, but there is an alternative source called xenon lamps. They provide around 6,000-7,000W of power for projection; but this has also increased the cost of projection units due to power and lamp replacements. In the industry, this calls for a new priority with regard to projection systems, namely longer lifetimes, low etendue (the spread of light in area and angle), and wider color gamuts. The solution to this problem is a laser-based light source that can be stable, as well as providing constant power over a narrow wavelength. This in turn allows for faster warm-up time, low noise, and thermal performance. These lasers would also assist in 3D movie projection due to the fact that they offer a 60% power advantage over lamp-based systems.
It was recently reported that a laser-based white light source could be used for projectors using red edge-emitting lasers at 640nm and green and blue Necsel arrays of 24 emitters each operating at 532 and 465nm, respectively. “Twenty-seven fiber-coupled 3W RGB lasers (nine per color) were used to produce over 81W of RGB power, equivalent to about 20,000 lumens at the source.” This allows for reduced cost and higher efficiency for the lamps, allowing for scalable, dependable, and easily-to-create products. Finally, the viewing experience is to be enhanced due to the laser projection. According to the review, “The much broader color spectrum, better contrast, lower noise, and improved 3D rendering will impress audiences and provide new impetus for content creators to generate videos that can take advantage of these features.”
[via SPIE]
