The History of Infrared Photography (contd.)
In the following years, experiments on the subject were
conducted by Joseph von Fraunhofer (1787-1826), a German
scientist and Sir John Herschel, son of Sir William.
It was Sir William Abney, president of The Royal Astronomical
Society and of The Physical Society of London, who devised
the earliest method of direct photography far into the infrared
region. Abney published a chart of the infrared region of the
solar spectrum, and is credited with first using the term
"infra-red," in 1880.
After years of further experiments, in 1904, Ben Homelike, an
Austrian chemist, discovered the first practical sensitizer for
all visible red, pinacyanol. Immediately after the invention of
pinacyanol came dicyanide, the first infrared sensitizer.