Joseph Hasner, Ritter von Artha (August 13, 1819 – February 2, 1892) was an Austrian ophthalmologist born in Prague. His brother, Leopold Hasner von Artha (1818–1891), was an influential Austrian politician.He studied medicine at the University of Prague, and subsequently worked at the local general hospital (1842). In 1843 he was an assistant at Johann Fischer's eye clinic. In 1848 he gained his habilitation, and in 1852 he became an associate professor.