On September 30, 1901, exactly 125 years ago, Indian physicist Jagadish Chandra Bose filed a patent application in the United States for a "Detector for Electrical Disturbances." Granted on March 29, 1904, as US Patent No. 755,840, it is widely described as the first US patent awarded to an Indian, and it covered one of the earliest semiconductor devices ever made.
What Bose Invented
Bose, then a professor of physics at Presidency College in Calcutta, had been studying radio waves at very short wavelengths. His patent described a detector for "electrical disturbances, Hertzian waves, light-waves, and other radiations" that used galena, a crystal of lead sulphide, as its sensitive material. By touching the crystal with a fine metal point, the device could detect incoming radio signals.
The Computer History Museum in California describes the patent as covering a point-contact semiconductor rectifier for detecting radio signals, a forerunner of the "cat's whisker" crystal detectors that powered early radio sets before vacuum tubes took over.
The Reluctant Patent-Holder
Bose was famously opposed to patenting scientific discoveries, believing knowledge should be freely available. He filed the application only after being persuaded by his American friend Sara Chapman Bull, who was assigned a half share in the patent. Years later, when he founded the Bose Institute in Kolkata in 1917, he reportedly ensured its founding documents barred members from seeking patents.
A Legacy Still Being Recognised
Beyond his detector, Bose built millimetre-wave transmitters, waveguides and horn antennas, designs that remain in use in modern forms today. He later turned to plant physiology, pioneering instruments that measured how plants respond to stimuli. Historians and engineers increasingly regard him as one of the founding figures of radio science.
Sources
US Patent 755,840 (via Wikisource); Computer History Museum; IEEE India Council; EDN.