Bulb, Laser, or LED?
When trying to determine what type of projector to use, the first thing you need to look at is the projector’s Lumens. The standard for determining a projector’s brightness is called ANSI Lumens. An ANSI Lumen rating uses an average of several brightness measurements taken across the face of the light source. So how many Lumens are right for your application? A good rule of thumb is if it’s too bright you can turn it down, but you can’t turn it up if it’s not bright enough, at least not without sacrificing image size.
Today’s projectors produce light in three different ways – lamps, lasers, and LED. In this article, we’re going to take you through the advantages and disadvantages of each technology as well as help you understand which light source could better complement the environment that the projector is going to be installed.
Lamp Based Light Sources
The original projector light source that is still in use today, is the lamp. Metal halide and UHP (Ultra High Performance) are the two types of lamps most commonly used. Metal halide lamps use a combination of rare earth metal salts and mercury vapor to deliver light. Mercury lamps produced a really bright light but have a significant downside. Because of the mercury, there is a high cost of operation and there can be disposal issues.
The downside with most lamp based light sources is their effective brightness degrades from day one and they generate a lot of heat thus require cooling, which requires more space, increasing the projector’s size and the amount of noise. Lamps have the shortest life span of all the lighting solutions available today and the simple act of turning the projector on and off diminishes the lamp’s operating life.
So why would you recommend a lamp as a light source? It comes down to cost and light quality. Lamp-based systems are less expensive but also have the shortest life. Lamps could be the choice if the projector is not being heavily used. For example, where the projector is only being used for an hour or two each day, the lamp’s reduced initial hardware costs can make it a better value.
There are several benefits shared by all projectors that use lasers as a light source. First, laser-based light engines turn on within seconds of pressing the power button. They are also incredibly reliable, lasting anywhere from 20k to 30k hours, and are mostly maintenance-free. Laser light engines are incredibly bright compared to lamps and most LED-based light systems, so they would typically be the best option for projecting on large surfaces.
A couple options for laser projectors include the Sony VW915
LED light engines use inorganic LED light-sources in place of a consumable lamp. Like laser light sources, LED light engines are also highly reliable and can offer up to 20,000 hours of use with no maintenance needed resulting in lower-cost operations. LED light sources are mercury-free and can power off and on quickly, even compared to laser light engines.
Using LED as a light source has been growing in popularity, mainly due to their small size, low heat, and affordability. Traditionally LED light engines are found in smaller, more portable projectors like a PICO projector.
Business and education installations will value the performance and color accuracy of RGB LED-based light engines. These projectors are perfect for classroom and conference room type environments able to produce laser competitive colors, reliability, and, with the exception of brightness, do it at a lower price.
An example of an LED projector would be the Panasonic PT-LRZ35U
Learn More about Light Sources