From Radio Receivers to LED Flashlights: An LED Odyssey

FROM RADIO RECEIVERS TO LED FLASHLIGHTS: 2007 AN LED ODYSSEY Cutting out the Competition: The U.S. joins a growing wave of nations pledging to phase out inefficient incandescent light bulbs by 2014. LEDS 1993 How the light-emitting diode evolved from a technology nobody cared about into the hottest innovation in energy-efficient lighting An LED Revolution: 1980's become a top contender to take their place. The first high-brightness blue LED is created, making white Also aboard the phase-out train: Brazil, Venezuela, European Union, Switzerland, Australia, Argentina, Russia, Canada, Malaysia Rising LED light possible. LEDS evolve from lowly indicator lights to a viable source of illumination. Star: 1968 Starting at the Bottom: The semiconductor materials used in LEDS are further refined, allowing scientists to create red, yellow, orange and green LEDS 10x brighter than previous versions. These developments launch 1962 LEDS into their new status as the dominant 1907 Now mass-produced, LEDS make A Bulb is Born: lighting solution for a variety of applications. their commercial debut as indicator lights in Hewlett Packard calculators. Refusing to be pigeonholed, they also start appearing in digital displays on TVs, radios, telephones, calculators and watches. $90,000 Look into the Crystal: The first LED bright enough for use - red - is created by Nick Holonyak Jr. of General Electric. Holonyak later becomes known as the "father of the LED." The amount Santa Monica, Calif., saves on annual power costs after converting 3,590 traffic signals to LEDS in 2001. Scientists notice that the crystals used in radio receivers emit light when electricity is passed through them. (They eventually give it a fancy name: electroluminescence.) Many of the LEDS made in the 1970s and $.05 1980s are still in service today. $200 The cost of a single LED in the 1970s, thanks to new processing techniques that are still used today. 2001 The cost of a single 1989 LED before 1968. Since the 1960s, LEDS LED Goes Portable: Stopping Traffic: have doubled in brightness about every three years. | 1972 The first LED flashlight is designed, offering more power and longer running times than incandescent models. Inventor Raymond Deese creates the first LED traffic light. Once again, no one cares - until years later, when the energy crisis hits. (By the turn of the century, New York City and many other U.S. cities will begin converting to LED traffic signals.) 1927 | 1963 Going Needs More Proud Green: Duct Tape: Father: Scientist M. George Craford creates green and yellow LEDS by using a different type of crystal semiconductor. (Without a viable blue LED, however, white light is not yet possible. A Russian inventor puts MacGyver to shame by building the first light-emitting diode using a thin wire and a crystal semiconductor. But the light is too dim for practical use; his invention meets radio silence. In the Feb. issue of Reader's Digest, Holonyak predicts his brainchild will someday replace Edison's incandescent light bulb.