Lee De Forest
Lee de Forest (born August 26, 1873 in Council Bluffs , Iowa , † June 30, 1961 in Hollywood , California ; actually Lee DeForest ) was an American inventor . Over 300 patents have been issued in his name.
De Forest invented the gas-filled Audion tube, the forerunner of the high vacuum triode , a 3-electrode tube that could be used to amplify weak electrical signals, and applied for a patent on October 25, 1906. He is known as one of the fathers of the electronic age, as audion contributed significantly to the spread of electronic devices.
De Forest was involved in several patent disputes and used the fortune he had made with his inventions for legal costs. He was married four times, failed multiple companies, was defrauded by some of his business associates, and was once charged with stock fraud. He was later acquitted of this charge.
Early years
De Forest was born in Iowa to the parish minister Henry Swift DeForest; his mother was Anna Margaret DeForest, née Robbins. Lee had an older sister and a younger brother.
His father hoped Lee would continue to serve as a priest. 1879 his father took the office of university presidents at Talladega College , a school for blacks in Talladega ( Alabama on). It was there that Lee spent most of his young life. Most of the white community stumbled upon his father's teaching blacks. Lee had some friends among the town's black boys.
De Forest enrolled in the Sheffield School of Science at Yale University in 1893 . As a curious student, he caused a complete blackout on the school grounds one evening when he tried to tap into the university's electrical system. He was then suspended from school. Some time later, he was allowed to finish his studies. He earned part of his school fees with inventions, and received his bachelor's degree in 1896. He received his doctorate from Yale in 1899, his doctoral thesis on radio waves .
De Forest was interested in wireless telegraphy , which led to the invention of the Audion tube in 1906, and he developed a wireless telegraph receiver. He filed a patent for a "two-electrode component" for the detection of electromagnetic waves . With the Audion tube, a gas-filled tube, it was possible to amplify speech during radio reception. De Forest said he didn't know why it worked, it just did. Robert von Lieben writes about the Audion tube: "... has the obvious disadvantage that due to the valve effect of the glowing cathode only half waves can pass between the cathode and the other electrodes".
He was a founding member of the Institute of Radio Engineers , one of the two predecessors of the IEEE .
Middle years
In 1906, de Forest invented the audion as an improvement on the tube diode used at that time and registered his invention as a patent. This tube was later also called the De Forest valve and is now known as the triode . De Forest's innovation was the insertion of a third electrode, the grid , between the cathode and the anode in the diode invented by John Ambrose Fleming . He was then accused of imitation by Fleming.
The resulting triode or three-electrode tube could be used as an amplifier for audio signals and - just as important - as a (for this time) fast switching element. In 1907, de Forest went on air for the first time as a test , with a conversation about the women's rights movement that he had with his mother-in-law Harriot Eaton Stanton Blatch , a well-known suffragette .
The United States District Attorney and three of his business associates sued de Forest in 1913 for stock fraud; de Forest alone was acquitted of this charge.
In 1916, de Forest filed a patent that sparked a controversial process with the prolific inventor Edwin Armstrong , who had received a patent on the regenerative circuit in 1914 . The process lasted twelve years and went through appeals to the Supreme Court . There it was decided in favor of de Forest; however, most historians hold this judgment wrong.
In 1916, de Forest aired the first radio commercials (for his own products) on his news network and he was the first to broadcast a presidential election report. Although he aired the first music program (with recordings by Enrico Caruso , 1910) and brought many other events to the radio, he received little support.
It is reported that he in the early twenties his classmates Theodore Willard Case Yale the idea of sound film steel. In 1922 de Forest improved the work of German inventors and developed the Phonofilm . In the phonofilm, the sound was recorded directly on the film with parallel lines. The sound was converted into electrical impulses by a microphone and then recorded photographically as lines. When played back, these lines were then converted back into sound. With the Phonofilm system, which recorded the sound in sync with the picture, stage performances, speeches and music performances could be recorded.
De Forest founded De Forest Phonofilm Corporation , which produced films such as Songs of Yesterday (1922), Noble Sissle and Eubie Blake Sing Snappy Songs , A Few Moments with Eddie Cantor (1923), and Ben Bernie and All the Lads (1925). But at that time he couldn't interest anyone in Hollywood in his invention. A few years later, Hollywood decided on a different recording system, but later came back to the technique developed by de Forest.
Shortly after the Audion was patented in 1907, De Forest married his assistant, the civil engineer Nora Stanton Blatch Barney , with whom he had a daughter.
Late years
In 1931 Lee de Forest sold one of his companies to RCA . In 1934 the Supreme Court ruled in favor of de Forests in the patent dispute with Armstrong. Although he won the process, he lost public reputation. He was not seen in public opinion as a serious inventor and no longer trusted him as a colleague. In 1946 he received the IEEE Edison Medal for his pioneering work in radio technology and the invention of the triode.
His sound recording method, initially rejected, was later introduced into film. In 1959/1960 he received an Oscar for "his groundbreaking invention that brought sound to moving images" and a star on the Hollywood Walk of Fame .
Lee de Forest died in Hollywood in 1961 and was buried in the San Fernando Mission Cemetery in Los Angeles, California.
In 1970 a moon crater was named after him.
Important patents
- Patent US841387 : Device For Amplifying Feeble Electrical Currents. Registered on October 25, 1906 , inventor: Lee de Forest (The de Forest trio).
- Patent US879532 : Space Telegraphy. Registered on January 29, 1907 , inventor: Lee de Forest (audion with triode).
literature
- Tom Lewis: Empire of the Air: The Men Who Made Radio . Harpercollins 1991. ISBN 0-06-018215-6
Web links
- IEEE History Center (Engl.) ( Memento of 24 June 2006 at the Internet Archive ) IEEE-page biographical information
- Lee de Forest in the Hall of Fame (Engl.) ( Memento of 5 October 2013 Internet Archive ) The pantheon of inventors
- The Perham Collection of History San Jose (Engl.) Lee de Forest
- Film about the Audion Public Broadcasting Service film in Quicktime
Individual evidence
- ↑ de Forest, Patent US841387 of October 25, 1906, an evacuated vessel inclosing a sensitive gaseous medium
- ↑ a b Patent US841387 : Device For Amplifying Feeble Electrical Currents. Registered on October 25, 1906 , inventor: Lee de Forest (The de Forest trio).
- ^ Von Lieben, Reisz, Strauss, DRP249142 of December 20, 1910
- ↑ Bill Jaker; Frank Sulek: The Airwaves of New York, Mcfarland & Co Inc, New York 2006, p. 1
- ^ Margaret E. Layne: Women in Engineering: Pioneers and Trailblazers, American Society of Civil Engineers, 2009
- ^ The winners of the IEEE Edison Medal, p.6 (PDF; 151 kB)
- ↑ De Forest in the Gazetteer of Planetary Nomenclature of the IAU (WGPSN) / USGS
| personal data | |
|---|---|
| SURNAME | De Forest, Lee |
| ALTERNATIVE NAMES | DeForest, Lee (real name) |
| BRIEF DESCRIPTION | American engineer and inventor |
| DATE OF BIRTH | August 26, 1873 |
| PLACE OF BIRTH | Council Bluffs , Iowa |
| DATE OF DEATH | June 30, 1961 |
| Place of death | Hollywood , California |