In 2008, LEDs made up 25 percent of the total $18.7 billion optoelectronics industry, making it the second largest product market behind image sensors. These products are simple semiconductor components that emit a visible colored light when an electric current is applied in the forward direction of the device. LEDs are referred to as “solid-state devices” meaning that they produce light from a single solid component, rather than the traditional tubes or vacuums of other light bulbs.
LEDs have several advantages over other light emitting electronics including overall improved efficiency that allow them to produce more light per watt than incandescent bulbs. They also have a slower failure rate, meaning that they gradually dim over long periods rather than simply burn out. Also, along with longer lifetimes, lower toxicity, they are very small which allow them to be easily populated onto printed circuit boards to backlight LCDs or illuminate a keyboard button.
Besides lighting, interesting new applications for UV-LEDs include water sterilization and as lights to stimulate plant growth. With the addition of blue LEDs, full color scanners and high resolution displays are also being introduced to the market.
The real trend in application penetration however, is primarily for HB-LEDs which are on their way to replace the incandescent bulbs that are everywhere today. Already there has been significant momentum in the usage of HB-LEDs, which are already showing up in televisions, mobile phones, cars and trucks.
In 2008, 61 billion LED units were shipped, due to a reduction in costs this number is predicted to continue to grow strongly at 23 percent annually on average until it reaches 175 billion units in five years. This will cause the entire LED market to account for over $10 billion in total worldwide revenue by 2013.