Humanities › History & Culture Television History - Paul Nipkow Paul Nipkow proposed and patented the first electromechanical television system Share Flipboard Email Print Eckhard Etzold / Wikimedia Common / Creative Commons History & Culture Inventions Famous Inventions Famous Inventors Patents & Trademarks Invention Timelines Computers & The Internet American History African American History African History Ancient History and Culture Asian History European History Genealogy Latin American History Medieval & Renaissance History Military History The 20th Century Women's History View More By Mary Bellis Inventions Expert Mary Bellis covered inventions and inventors for ThoughtCo for 18 years. She is known for her independent films and documentaries, including one about Alexander Graham Bell. our editorial process Mary Bellis Updated April 06, 2017 German engineering student, Paul Nipkow proposed and patented the world's first mechanical television system in 1884. Paul Nipkow devised the notion of dissecting the image and transmitting it sequentially. To do this he designed the first television scanning device. Paul Nipkow was the first person to discover television's scanning principle, in which the light intensities of small portions of an image are successively analyzed and transmitted. In 1873, the photoconductive properties of the element selenium were discovered, the fact that selenium's electrical conduction varied with the amount of illumination it received. Paul Nipkow created a rotating scanning disk camera called the Nipkow disk, a device for picture analyzation that consisted of a rapidly rotating disk placed between a scene and a light sensitive selenium element. The image had only 18 lines of resolution. Nipkow Disk According to R. J. Reiman author of Who Invented Television: The Nipkow disk was a rotating disk with holes arranged in a spiral around its edge. Light passing through the holes as the disk rotated produced a rectangular scanning pattern or raster which could be used to either generate an electrical signal from the scene for transmitting or to produce an image from the signal at the receiver. As the disk rotated, the image was scanned by the perforations in the disk, and light from different portions of it passed to a selenium photocell. The number of scanned lines was equal to the number of perforations and each rotation of the disk produced a television frame. In the receiver, the brightness of the light source would be varied by the signal voltage. Again, the light passed through a synchronously rotating perforated disk and formed a raster on the projection screen. Mechanical viewers had the serious limitation of resolution and brightness. No one is sure if Paul Nipkow actually built a working prototype of his television system. It would take the development of the amplification tube in 1907 before the Nipkow Disk could become practical. All mechanical television systems were outmoded in 1934 by electronic television systems.