History of infrared science

The discovery of infrared radiation is ascribed to William Herschel, the astronomer, in the early 19th century. Herschel published his results in 1800 before the Royal Society of London. Herschel used a prism to refract light from the sun and detected the infrared, beyond the red part of the spectrum, through an increase in the temperature recorded on a thermometer. He was surprised at the result and called them "Calorific Rays". The term "infrared" did not appear until late 19th century.

Other important dates include:

• 1737: Émilie du Châtelet predicted what is today known as infrared radiation in Dissertation sur la nature et la propagation du feu.
• 1830: Leopoldo Nobili made the first thermopile IR detector.
• 1840: John Herschel produces the first thermal image, called a thermogram.
• 1860: Gustav Kirchhoff formulated the blackbody theorem ${\displaystyle E=J(T,n)}$.
• 1873: Willoughby Smith discovered the photoconductivity of selenium.
• 1878: Samuel Pierpont Langley invents the first bolometer, a device which is able to measure small temperature fluctuations, and thus the power of far infrared sources.
• 1879: Stefan–Boltzmann law formulated empirically that the power radiated by a blackbody is proportional to T4.
• 1880s and 1890s: Lord Rayleigh and Wilhelm Wien solved part of the blackbody equation, but both solutions diverged in parts of the electromagnetic spectrum. This problem was called the "ultraviolet catastrophe and infrared catastrophe".
• 1892: Willem Henri Julius published infrared spectra of 20 organic compounds measured with a bolometer in units of angular displacement.
• 1901: Max Planck published the blackbody equation and theorem. He solved the problem by quantizing the allowable energy transitions.
• 1905: Albert Einstein developed the theory of the photoelectric effect.
• 1905–1908: William Coblentz published infrared spectra in units of wavelength (micrometers) for several chemical compounds in Investigations of Infra-Red Spectra.
• 1917: Theodore Case developed the thallous sulfide detector; British scientist built the first infra-red search and track (IRST) device able to detect aircraft at a range of one mile (1.6 km).
• 1935: Lead salts – early missile guidance in World War II.
• 1938: Yeou Ta predicted that the pyroelectric effect could be used to detect infrared radiation.
• 1945: The Zielgerät 1229 "Vampir" infrared weapon system was introduced as the first portable infrared device for military applications.
• 1952: Heinrich Welker grew synthetic InSb crystals.
• 1950s and 1960s: Nomenclature and radiometric units defined by Fred Nicodemenus, G. J. Zissis and R. Clark; Robert Clark Jones defined D*.
• 1958: W. D. Lawson (Royal Radar Establishment in Malvern) discovered IR detection properties of Mercury cadmium telluride (HgCdTe).
• 1958: Falcon and Sidewinder missiles were developed using infrared technology.
• 1960s: Paul Kruse and his colleagues at Honeywell Research Center demonstrate the use of HgCdTe as an effective compound for infrared detection.
• 1962: J. Cooper demonstrated pyroelectric detection.
• 1964: W. G. Evans discovered infrared thermoreceptors in a pyrophile beetle.
• 1965: First IR handbook; first commercial imagers (Barnes, Agema (now part of FLIR Systems Inc.)); Richard Hudson's landmark text; F4 TRAM FLIR by Hughes; phenomenology pioneered by Fred Simmons and A. T. Stair; U.S. Army's night vision lab formed (now Night Vision and Electronic Sensors Directorate (NVESD)), and Rachets develops detection, recognition and identification modeling there.
• 1970: Willard Boyle and George E. Smith proposed CCD at Bell Labs for picture phone.
• 1973: Common module program started by NVESD.
• 1978: Infrared imaging astronomy came of age, observatories planned, IRTF on Mauna Kea opened; 32 × 32 and 64 × 64 arrays produced using InSb, HgCdTe and other materials.
• 2013: On 14 February, researchers developed a neural implant that gives rats the ability to sense infrared light, which for the first time provides living creatures with new abilities, instead of simply replacing or augmenting existing abilities.