A light-emitting diode is an electronic semiconductor device which is used in digital displays and lamps. In general lighting, incandescent light bulbs are still the most widely used electric lights today. However, many countries, including the United States, have begun to phase out incandescent lamps in favor of more energy-efficient light sources such as light-emitting diodes and organic light-emitting diodes. Residential LED products are expected to use at least 75 percent less energy and last up to 25 times longer than the traditional incandescent lamps. Unlike incandescent bulbs which lose most of their energy as heat, LEDs can more efficiently use energy. The widespread use of LED lighting can greatly reduce electricity consumption.
In 2020, LEDs are estimated to achieve a 61 percent penetration of the global lighting market. As Asian countries are likely to increase their share in global sapphire production, thus eroding the price of semiconductors, the cost of LED lamps is expected to decrease rapidly. Currently, LED lighting is predominantly used as a backlight technology for television and mobile phone screens. As of 2015, the lighting segment dominated the overall LED market worldwide. LEDs are applicable to many different uses due to its compact size, resistance to breakage, and ability to focus light in one direction. Its ability to focus in one direction reduces the need for reflectors and other diffusers that trap light, making it useful for various purposes such as task lighting.