From spotlights to downlights, strip lighting to different sized bulbs, not to mention fairy lights for the Christmas tree; LED bulbs have fast become the preferred choice of many homeowners, traders, builders and commercial developers. Currently the most energy-efficient lighting technology available for use in commercial and business purposes, and it is only natural that it is also one of the most rapidly-developing technologies. They’re both decorative and practical, making them suitable for a range of rooms and buildings. By definition, the light-emitting diode (LED) is an electric component that emits light when connected to direct current. They have characteristically low energy consumption, small size, longer lifetime and faster switching than incandescence lamps and because of that, they have a wide palette of applicability. Like many other areas of technology, LED lights have evolved as time has progressed. LED bulbs use very little energy and have the longest lifespan of any bulb on the market, thus making them a more environmentally viable option. British experimenter in Marconi labs, Henry Joseph Round, in 1907, noticed for the first time that when a potential of 10volts is applied to carborundum (silicon carbide) crystal, it emits yellowish light. However, first to investigate it and to propose a working theory was Oleg Vladimirovich Losev from Russia. In 1927, Oleg published a paper “Luminous carborundum detector and detection effect and oscillations with crystals“. This is according to Historyoflighting.net According to shine retrofits, Robert Biard and Gary Pittman, in 1961, invented an infra-red LED while they were working for Texas Instruments. However, this light did not have any practical use because it was invisible to human beings. This was an accidental invention because Biard and Pittman were actually working on a laser diode. Although red and green LEDs had been around for many years, blue LEDs, invented in 1993 were a long-standing challenge for scientists in both academia and industry. Without them, the three colours could not be mixed to produce the white light we now see in LED-based computer and TV screens. Also, the high-energy blue light could be used to excite phosphorus and directly produce white light – the basis of the next generation of light bulb. Today, blue LEDs are found in people’s pockets around the world, inside the lights and screens of smartphones. The development of LED technology has caused their efficiency and light output to rise exponentially, with a doubling occurring approximately every 36 months since the 1960s, in a way similar to Moore’s law. editor@newtimesrwanda.com
