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1962 Nick Holonyak Jr. develops the first practical visible-spectrum (red) light-emitting diode. 1963 Kurt Schmidt invents the first high pressure sodium-vapor lamp. [17] 1972 M. George Craford invents the first yellow light-emitting diode. 1972 Herbert Paul Maruska and Jacques Pankove create the first violet light-emitting diode.
1878 – Thomas Edison, following work on a "multiplex telegraph" system and the phonograph, invents an improved incandescent light bulb. This was not the first electric light bulb but the first commercially practical incandescent light. In 1879 he produces a high-resistance lamp in a very high vacuum; the lamp lasts hundreds of hours. While ...
The history of street lighting in the United States is closely linked to the urbanization of America. Artificial illumination has stimulated commercial activity at night, and has been tied to the country's economic development, including major innovations in transportation, particularly the growth in automobile use. [ 1 ]
While indirect lighting can create a diffused and shadow free light effect it can be regarded as an uneconomical lighting principle. [12] [13] Front lighting is also quite common, but tends to make the subject look flat as its casts almost no visible shadows. Lighting from the side is the less common, as it tends to produce glare near eye level.
The early writers discussed here treated vision more as a geometrical than as a physical, physiological, or psychological problem. The first known author of a treatise on geometrical optics was the geometer Euclid (c. 325 BC–265 BC).
Engraving of the Cordouan lighthouse, completed in 1611. During the European Middle Ages, many Roman lighthouses fell into disuse. Some did remain functional, such as the Farum Brigantium, now known as the Tower of Hercules, in A Coruña, Spain, and others in the Mediterranean Sea, such as the Lanterna at Genoa.
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Gas light cost up to 75% less than oil lamps or candles, which helped to accelerate its development and deployment. By 1859, gas lighting was to be found all over Britain and about a thousand gas works had sprung up to meet the demand for the new fuel. The brighter lighting which gas provided allowed people to read more easily and for longer.