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Nick Holonyak Jr. (/ h ʌ l ɒ n j æ k / huh-LON-yak; November 3, 1928 – September 18, 2022) was an American engineer and educator.He is noted particularly for his 1962 invention and first demonstration of a semiconductor laser diode that emitted visible light.
Celebrating 50 years since the advent of LED technology, Nick Holonyak compares his first visible LED invention to GE Lighting's latest 27-watt LED available in 2013, replacing the 100-watt ...
Visible-light spectroscopy is an important tool in astronomy (as is spectroscopy at other wavelengths), where scientists use it to analyze the properties of distant objects. Chemical elements and small molecules can be detected in astronomical objects by observing emission lines and absorption lines.
The device used the semiconducting alloy gallium phosphide arsenide (GaAsP). It was the first semiconductor laser to emit visible light, albeit at low temperatures. At room temperature it still functioned as a red light-emitting diode. GaAsP was the basis for the first wave of commercial LEDs emitting visible light.
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. [18] 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.
Light, visible light, or visible radiation is electromagnetic radiation that can be perceived by the human eye. [1] Visible light spans the visible spectrum and is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequencies of 750–420 terahertz .
Cooling is not required and visible and infrared light appear in a single image. Its frequency range is 1550-nm infrared to visible 550-nm light. Because, traditionally, night-vision systems capture side-by-side views from each spectrum, they can't produce identical images unlike films applied to ordinary glasses.
The laser was invented because spectroscopists took the concept of its predecessor, the maser, and applied it to the visible and infrared ranges of light. [87] The maser was invented by Charles Townes and other spectroscopists to stimulate matter to determine the radiative frequencies that specific atoms and molecules emitted. [87]