Humphrey Lloyd (16.04.1800-17.01.1881) was an Irish physicist and a member of the Royal Irish Academy, its president in 1846—51. He was born in Dublin. He graduated from the University of Dublin (1819), where he worked (professor from 1831, provost from 1867).
His research was in the field of mechanics, optics and terrestrial magnetism. He proposed a method of obtaining an interference pattern from a single mirror, showing that optical interference can be obtained by making the direct light and the light reflected from the mirror interfere (1837). He discovered (1832) conical refraction, which had been predicted by W. Hamilton.
A Fellow of the Royal Society and of the Royal Society of Edinburgh.