József Petzvál

Invention: Achromatic portrait lens, Dark room, Projector

József Miksa Petzval was born in Szepesbéla and died in Vienna. He became an engineer at the Institutum Geometricum in Pest and later received a Ph.D. degree in mathematics. He taught mathematics and mechanics at the Universities of Pest and Vienna.

In Petzval's time, two French scientists invented photography. The luminosity of the optical lens was so weak that taking pictures of persons was impossible because it took at least 30 minutes. In 1840 Petzval designed a double lens, that reduced the time of taking a picture to seconds. The first lens was cut by Voigtländer, a German optician, according to the calculations and directions of Petzval. This lens made portrait photography possible and became the basis of the photographic industry.
A large camera factory under the name of Voigtländer is still operating in Germany.

Nobody mentions the name of Petzval. The same thing happened to him as to Ányos Jedlik. Petzval built the first dark room.