Sir Chandrasekhara Venkata Raman, (7 November 1888 – 21 November 1970) was an Indian physicist, born in the former Madras Province, discovered that, when light traverses a transparent material, some of the deflected light changes in wavelength called Raman Effect earned him the 1930 Nobel Prize for Physics. In 1954, he was honoured with the highest civilian award in India, the Bharat Ratna.
Raman employed monochromatic light from a mercury arc lamp which penetrated transparent material and was allowed to fall on a spectrograph to record its spectrum. He detected lines in the spectrum which he later called Raman lines. He presented his theory at a meeting of scientists in Bangalore on 16 March 1928, and won the Nobel Prize in Physics in 1930.
Raman Effect: fingerprinting the universe
Raman's discovery has finally become a breakthrough technology. Hand-held scanners called Raman scanners, weighing just one-third of a kilo, are being used by US narcotics squads and airports to detect drugs.
Security experts think that Raman scanners may be the best devices to detect explosives carried by terrorists.
Safety inspectors are using Raman scanners to detect hazardous chemicals and gases.
Police forces are using Raman scanners for forensic work.
Researchers at UCLA and Intel have incorporated the Raman Effect on silicon. Because of its crystalline structure, the Raman Effect is 10,000 times stronger in silicon than glass. Researchers at JPL and Caltech have found other ways to increase laser efficiency. This has driven down size and costs.
Researchers at Stanford University are experimenting with Raman scanners to diagnose cancers in various organs. River Diagnostics in Rotterdam is marketing a bacteria analyzer that hospitals can use to instantly detect deadly pathogens. One day, Raman scanners may make blood tests obsolete: a scan may suffice to tell you the content of glucose, cholesterol, uric acid and other elements in blood.
Every molecule has a different Raman pattern. This is why Raman scanning has been called the fingerprinting of the universe: it can identify substances as surely as fingerprints can identify humans.
Identifying the chemical composition of a substance typically requires chemical and physical tests that take time, maybe days. They typically require a sample to be extracted and destroyed while testing. But Raman scanning can take just 20 seconds. It does not require cutting, extracting or destroying a substance. Scanners have a laser, spectroscope and an electronic heart that can recognize Raman patterns. This yields almost instant recognition of target substances.
For instance, narcotics squads in the US are using Raman scanners programmed to detect up to 100 drugs. At the scene of a crime, or during airport security checks, the scanner can tell whether a substance is heroin, crack cocaine, amphetamine, or plain chalk. Security experts can programme scanners to detect different sorts of explosives such as RDX or nitroglycerine.
FRIENDS-Join Hands to SHOWER Tributes to the man behind Raman Effect, Nobel Laureate & Bharat Ratna Sir CV Raman on his 127th birth anniversary.Scientists aim ultimately to create a database of Raman patterns of every substance for easy identification. This is similar to Nandan Nilekani creating a national database for fingerprints and irises to identify every Indian. Databases have already been created for narcotics, pollutants and explosives, which is why scanners have already become practical tools. Every time they are used to catch a drug smuggler or terrorist, or to detect a cancer or pollutant, we can give thanks to CV Raman. Science teachers can now teach students why exactly the Raman Effect is so important: it fingerprints the universe.
https://en.wikipedia.org/wiki/C._V._Raman
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