Gustaf Dalen (1869-1937), Swedish engineer and inventor. Dalen was awarded the 1912 Nobel Prize in Physics for inventing automated flashing beacons for lighthouses. He developed the use of dissolved acetylene for light, making it brighter and safer to store and use. He also invented the sun-valve, which automatically turned the light on at dusk and off again at dawn. In 1909 he became president of AGA, who sold his beacons. In 1912 Dalen was blinded by an explosion at the factory. He never regained his sight but remained an active head of AGA until his death. During that time he invented the AGA cooker. Dalen had almost 100 patents pending during his lifetime.