A LiFi bulb is a type of light bulb used in a rear-projection television set, to project the image onto the screen. These bulbs are much longer-lasting than their predecessors, with some claiming that they last so long, they may never need replacement. This technology was first available in 2007. The LiFi bulb also offers other advantages in addition to lasting longer, that are linked to its comparatively small size.
Most older television sets, which used a type of technology called a cathode ray tube (CRT) to project images, were made in such a way that the inner components were not meant to be replaced. Unplanned repairs might need to be made, of course, but that was the extent of it. CRT televisions are one type of rear-projection set, meaning that the image is projected onto a screen from behind. There are also newer rear-projection sets that do not utilize a CRT technology, but rather one that makes the set less bulky than comparable CRT sets, especially in larger sizes.
These later models utilized a type of specialized light bulb that projected images from a small liquid crystal display (LCD) screen onto the television screen. This meant a higher-quality picture than older CRT models, and lower cost than those with a flat screen. The one major disadvantage to the newer rear-projection models is that the light bulb responsible for image projection had a lifespan of only three to five years, with a replacement costing almost as much as the television itself.
The LiFi bulb was introduced in the year 2007 as an alternative to the light bulbs in rear-projection LCD televisions. This type of bulb was created by modifying another type known as a high-intensity discharge lamp. A LiFi bulb removes the main disadvantage inherent in rear-projection television sets, with a lifespan of 20,000 hours of use, as estimated by the manufacturer.
Not only is a LiFi bulb much longer-lasting than its older counterpart, it is also smaller, meaning that the time between turning the set on and seeing an image displayed on the screen is reduced. It also maintains its brightness as long as it is operational; in other words, its light will not get dimmer over time. The LiFi bulb is not the first technology to extend the amount of time between bulb replacement. Light-emitting diodes (LEDs) have also been used with the same effect, but these tended to significantly increase the retail price of televisions made this way.