Laser Illumination Sources for Projectors
Projector manufacturers have long sought to develop products that provide the best possible picture on a screen or surface. Lamps – whether large Xenon short-arc lamps or small mercury halide bulbs — have served well and provided the best solution for many years. But they have drawbacks, including: handling safety hazards, high-temperatures, relatively-short lifetimes and difficulty of transportation and disposal.
Theoretically, lasers are superior illumination sources to lamps and bulbs, due to several factors, including:
- Brighter pictures
- Lower power consumption
- Longer life and less-frequent changes
- Lower total cost of ownership
- Fewer heavy metals
- Expanded color gamut
- More flexible systems
Harnessing these advantages, and bringing them to market, has taken time as solid-state laser development is constantly advancing. Since 2000, (and possibly earlier, depending how its defined) lasers, and the necessary optics, have been steadily-developing specifically for projection applications. Now, products are rapidly coming to many markets for all projector sizes.
For most projectors, there is no outer change in the size or shape of a laser-illuminated versus a lamp-illuminated projector. As illustrated below, it is an internal-only ramification and can have no effect on the outer casing of the projector.
Projector designers basically create a new optical engine, powered by lasers, rather than a bulb. The engine is also different in the makeup of the optics and lenses which homogenize the laser light into a broad light field covering a full-spectrum of colors. The microdisplay – which could be a DMD, LCOS or LCD* – and final projection lenses are virtually identical in both style projectors.
RGB Laser Projector
Blue Laser Projector
*DMD® = Digital Micro Display
LCOS = liquid crystal on semiconductor
LCD = liquid crystal display