Eric Tigerstedt

Eric Magnus Campbell Tigerstedt (August 14, 1887 – April 20, 1925) was a Finnish inventor best known as one of the most significant inventors in Finland at the beginning of the 20th century and has been called the "Thomas Edison of Finland". He was a pioneer of sound-on-film technology and made significant improvements to the amplification capacity of the vacuum valve. Having seen a showing of the Lumière brothers' new motion picture technology as a nine-year-old boy in Helsinki in 1896, he was inspired to bring sound to silent pictures.

Many years later, in 1914, his demonstration film Word and Picture was presented to a gathering of scientific dignitaries in Berlin, but his invention was never commercialized. In addition to improving the triode vacuum valve, he developed directional loudspeakers. Tigerstedt also predicted such future inventions as television and he invented the mobile phone, for which he in 1917 successfully filed a patent. The patent was granted to Tigerstedt for what he described as a "pocket-size folding telephone with a very thin carbon microphone". Tigerstedt was awarded a total of 71 patents in several countries between the years 1912 and 1924.