Projector Light Source Technology
Projector light source technology has seen many changes in the past few years. From improvements to the traditional projector lamp to the introduction of lasers, the newest projector light sources are more efficient, environmentally-friendly and longer lasting than their predecessors.
Here is a breakdown of the most common projector light sources on the market today and a preview of what to expect in the future.
The majority of today's projectors use lamps as a light source. Compared to newer technology, the future of the lamp is dim. (Pun intended.)
Metal halide and UHP (Ultra High Performance) are the most common types of projector lamps.
Metal halide lamps, invented in the late 1960s, use a combination of rare earth metal salts and mercury vapor to deliver light. They last about 3,000 hours.
The UHP lamp was developed by Philips in 1995 as a more efficient alternative to the metal halide. It provides similar brightness with less energy and also lasts about 3,000 hours.
The newest lamp on the scene is Epson's E-TORL, which features a redesigned housing and lamp shape. The improvements minimize light diffraction and leakage, and focus as much brightness as possible onto the display. The E-TORL lamp lasts about 4,000 hours.
To get the most out of your lamp, check out our guide to extending your projector's lamp life.
Warning: The mercury in projector lamps can leak into the groundwater if disposed of improperly. The latest advancements in light source technology are mercury-free. While we wait for these to become the new standard, you can use this site to find a recyle location near you to help you dispose of your used lamps in an environmentally-safe way: www.recyclerfinder.com
Used in most pico projectors, LEDs (light-emitting diodes) are essentially tiny light bulbs.
But unlike the light bulb in your desk lamp, LEDs fit directly into an electrical circuit and are illuminated by the flow of electrons. LEDs do not have a filament, like regular bulbs, and therefore last much, much longer. The lack of filament also allows the LEDs to operate more efficiently than traditional bulbs. They do not get as hot and require far less electric power.
LED light sources are mercury-free and can power off and on instantly. They do not require a fan to control their operating temperature, and therefore allow for quieter and smaller projectors. LED projectors are typically not as bright as those powered by other light sources.
Hybrid Light Source
Casio was the first full-size projector manufacturer to do away completely with lamps. Their Hybrid Light Source capitalizes on the best of laser, fluorescent and LED technologies to produce an image just as bright as mercury lamps, but also longer lasting, more eco-friendly and far less power consuming. We're expecting this technology to spread quickly throughout the projector world.
At 2,000-3,000 lumens, this hybrid projector far outshines its LED-only predecessors. The Hybrid Light Source uses a red LED and a blue laser. A fluorescent element converts blue laser light into green light.
While the performance of conventional projector mercury lamps falls off visibly with increasing age, the Hybrid Light Source maintains consistent brightness and superior color.
The Hybrid Light Source lasts up to 20,000 hours. It reaches its maximum brightness in a mere eight seconds and requires no cooling down period. Old mercury lamps can be damaged if unplugged before the cooling down period ends.
On the Horizon . . . Lasers!
In early 2010, Sony announced the development of a highly-efficient RGB laser light source with a lifespan of 10,000 hours.
The light source uses high-power red, green and blue lasers with a combined output of 21 watts, equivalent to 5,000 lumens. With energy consumption at just 110 watts, Sony has achieved an 18% energy conversion ratio, a very respectable feat for this technology. Lower energy consumption equals lower power bills.
Also respectable is the lasers' considerably higher brightness, better contrast and wider color gamut compared to traditional projector lamps.
It's unknown when these new laser light sources will hit the market.