Timeline of United States inventions (1946–91) of the United States Geological Survey. 1960 Gas laser A gas laser is a laser in which an electric current is discharged through a gas to produce light. The first gas laser, the Helium-neon, was invented by William R. Bennett, Don Herriott, and Ali Javan in 1960. The first continuous visible gas laser, operating at 632.8 nm in the red, was invented by A. D. White and J. D. Rigden in 1962. 1961 Spreadsheet (electronic) 1961 Wearable computer 1961 Frozen carbonated beverage 1961 Biofeedback 1962 Communications satellite 1962 Chimney starter 1962 Light-emitting diode A light-emitting-diode (LED) is a semiconductor diode
Light-emitting diode city-dwellers led to some controversy. So far high-pressure sodium lamps (HPS) with an orange light spectrum were the most efficient light sources commonly used in street-lighting. Now many modern street lamps are equipped with Indium gallium nitride LEDs (InGaN). These are even more efficient and mostly emit blue-rich light with a higher "correlated color temperature (CCT)". Since light with a high CCT resembles daylight it is thought that this might have an effect on the normal circadian physiology by suppressing melatonin production in the human body. There have been no relevant studies as yet and critics claim exposure levels are