In 1921 de Forest ended most of his radio research in order to concentrate on developing an optical "sound-on-film process called "Phonofilm. In 1919 he filed the first patent for the new system, which improved upon earlier work by Finnish inventor "Eric Tigerstedt and the German partnership "Tri-Ergon. Phonofilm recorded the electrical waveforms produced by a microphone photographically onto film, using parallel lines of variable shades of gray, an approach known as "variable density", in contrast to "variable area" systems used by processes such as "RCA Photophone. When the movie film was projected, the recorded information was converted back into sound, in synchronization with the picture.
From October 1921 to September 1922, de Forest lived in "Berlin, Germany, meeting the Tri-Ergon developers (German inventors Josef Engl (1893–1942), Hans Vogt (1890–1979), and Joseph Massolle (1889–1957)) and investigating other European sound film systems. In April 1922 he announced that he would soon have a workable sound-on-film system. On March 12, 1923 he demonstrated Phonofilm to the press; this was followed on April 12, 1923 by a private demonstration to electrical engineers at the Engineering Society Building's Auditorium at 33 West 39th Street in New York City.
In November 1922, de Forest established the De Forest Phonofilm Company, located at 314 East 48th Street in New York City. But none of the "Hollywood movie studios expressed interest in his invention, and because at this time these studios controlled all the major theater chains, this meant de Forest was limited to showing his films in independent theaters. (The Phonofilm Company would file for bankruptcy in September 1926.)
After recording stage performances (such as in vaudeville), speeches, and musical acts, on April 15, 1923 de Forest premiered 18 Phonofilm short films at the independent Rivoli Theater in New York City. Starting in May 1924, "Max and "Dave Fleischer used the Phonofilm process for their "Song Car-Tune series of cartoons—featuring the ""Follow the Bouncing Ball" gimmick. However, de Forest's choice of primarily filming short "vaudeville acts, instead of full-length features, limited the appeal of Phonofilm to Hollywood studios.
De Forest also worked with "Freeman Harrison Owens and "Theodore Case, using their work to perfect the Phonofilm system. However, de Forest had a falling out with both men. Due to de Forest's continuing misuse of Theodore Case's inventions and failure to publicly acknowledge Case's contributions, the Case Research Laboratory proceeded to build its own camera. That camera was used by Case and his colleague Earl Sponable to record President Coolidge on August 11, 1924, which was one of the films shown by de Forest and claimed by him to be the product of "his" inventions.
Believing that de Forest was more concerned with his own fame and recognition than he was with actually creating a workable system of sound film, and because of his continuing attempts to downplay the contributions of the Case Research Laboratory in the creation of Phonofilm, Case severed his ties with de Forest in the fall of 1925. Case successfully negotiated an agreement to use his patents with studio head "William Fox, owner of "Fox Film Corporation, who marketed the innovation as "Fox Movietone. Hollywood introduced a competing method for sound film, the "Vitaphone "sound-on-disc process developed by "Warner Brothers, with the August 6, 1926 release of the "John Barrymore film "Don Juan.
In 1927 and 1928, Hollywood expanded its use of sound-on-film systems, including Fox Movietone and RCA Photophone. Meanwhile, theater chain owner Isadore Schlesinger purchased the "UK rights to Phonofilm and released short films of British "music hall performers from September 1926 to May 1929. Almost 200 Phonofilm shorts were made, and many are preserved in the collections of the "Library of Congress and the "British Film Institute.
Later years and death
In April 1923, the De Forest Radio Telephone & Telegraph Company, which manufactured de Forest's Audions for commercial use, was sold to a group headed by Edward Jewett of Jewett-Paige Motors, which expanded the company's factory to cope with rising demand for radios. The sale also bought the services of de Forest, who was focusing his attention on newer innovations. De Forest's finances were badly hurt by the stock market crash of 1929, and research in mechanical television proved unprofitable. In 1934, he established a small shop to produce "diathermy machines, and, in a 1942 interview, still hoped "to make at least one more great invention".
De Forest was a vocal critic of many of the developments in the entertainment side of the radio industry. In 1940 he sent an open letter to the "National Association of Broadcasters in which he demanded: "What have you done with my child, the radio broadcast? You have debased this child, dressed him in rags of ragtime, tatters of jive and boogie-woogie." That same year, de Forest and early TV engineer "Ulises Armand Sanabria presented the concept of a primitive "unmanned combat air vehicle using a "television camera and a jam-resistant radio control in a "Popular Mechanics issue. In 1950 his autobiography, Father of Radio, was published, although it sold poorly.
De Forest was the guest celebrity on the May 22, 1957, episode of the television show "This Is Your Life, where he was introduced as "the father of radio and the grandfather of television". He suffered a severe heart attack in 1958, after which he remained mostly bedridden. He died in Hollywood on June 30, 1961, aged 87, and was interred in "San Fernando Mission Cemetery in Los Angeles, California. De Forest died relatively poor, with just $1,250 in his bank account.
The grid Audion, which de Forest called "my greatest invention", and the vacuum tubes developed from it, dominated the field of "electronics for forty years, making possible long-distance telephone service, "radio broadcasting, television, and many other applications. It could also be used as an electronic switching element, and was later used in early digital electronics, including the first electronic computers, although the 1948 invention of the "transistor would lead to microchips that eventually supplanted vacuum-tube technology. For this reason de Forest has been called one of the founders of the "electronic age".
De Forest's archives were donated by his widow to the Perham Electronic Foundation, which in 1973 opened the Foothills Electronics Museum at "Foothill College in Los Altos, California. In 1991 the college closed the museum, breaking its contract. The foundation won a lawsuit and was awarded $775,000. The holdings were placed in storage for twelve years, before being acquired in 2003 by History San José and put on display as The Perham Collection of Early Electronics.
Awards and recognition
- Charter member, in 1912, of the "Institute of Radio Engineers (IRE).
- Received the 1922 IRE "Medal of Honor, in "recognition for his invention of the three-electrode amplifier and his other contributions to radio".
- Awarded the 1923 "Franklin Institute "Elliott Cresson Medal for "inventions embodied in the Audion".
- Received the 1946 "American Institute of Electrical Engineers "Edison Medal, "For the profound technical and social consequences of the grid-controlled vacuum tube which he had introduced".
- "Honorary Academy Award "Oscar presented by the "Academy of Motion Picture Arts and Sciences in 1960, in recognition of "his pioneering inventions which brought sound to the motion picture".
- Honored February 8, 1960 with a star on the "Hollywood Walk of Fame.
- "DeVry University was originally named the De Forest Training School by its founder Dr. Herman A. De Vry, who was a friend and colleague of de Forest.
De Forest was married four times, with the first three marriages ending in divorce:
- Lucille Sheardown in February 1906. Divorced before the end of the year.
- "Nora Stanton Blatch Barney (1883–1971) on February 14, 1908. They had a daughter, Harriet, but were divorced by 1911.
- Mary Mayo (1892–1957) in December 1912. According to census records, in 1920 they were living with their infant daughter, Deena (born ca. 1919); divorced October 5, 1930 (per Los Angeles Times). Mayo died December 30, 1957 in a fire in Los Angeles (Los Angeles Times, December 31, 1957)
- "Marie Mosquini (1899–1983) on October 10, 1930; Mosquini was a silent film actress, and they remained married until his death in 1961.
De Forest was a conservative Republican and fervent anti-communist and anti-fascist. In 1932, in the midst of the Great Depression, he voted for Franklin Roosevelt, but later came to resent him, calling Roosevelt America's "first Fascist president". In 1949, he "sent letters to all members of Congress urging them to vote against "socialized medicine, federally subsidized housing, and an excess profits tax". In 1952, he wrote to newly elected Vice President "Richard Nixon, urging him to "prosecute with renewed vigor your valiant fight to put out Communism from every branch of our government". In December 1953, he cancelled his subscription to "The Nation, accusing it of being "lousy with Treason, crawling with Communism."
Although raised in a strongly religious Protestant household, de Forest later became an agnostic. In his autobiography, he wrote that in the summer of 1894 there was an important shift in his beliefs: "Through that Freshman vacation at Yale I became more of a philosopher than I have ever since. And thus, one by one, were my childhood's firm religious beliefs altered or reluctantly discarded."
De Forest was given to expansive predictions, many of which were not borne out, but he also made many correct predictions, including microwave communication and cooking.
- "I discovered an Invisible Empire of the Air, intangible, yet solid as granite."
- "I foresee great refinements in the field of short-pulse microwave signaling, whereby several simultaneous programs may occupy the same channel, in sequence, with incredibly swift electronic communication. [...] Short waves will be generally used in the kitchen for roasting and baking, almost instantaneously." – 1952 
- "So I repeat that while theoretically and technically television may be feasible, yet commercially and financially, I consider it an impossibility; a development of which we need not waste little time in dreaming." – 1926
- "To place a man in a multi-stage rocket and project him into the controlling gravitational field of the moon where the passengers can make scientific observations, perhaps land alive, and then return to earth—all that constitutes a wild dream worthy of "Jules Verne. I am bold enough to say that such a man-made voyage will never occur regardless of all future advances." – 1957
- "I do not foresee 'spaceships' to the moon or Mars. Mortals must live and die on Earth or within its atmosphere!" – 1952
- "As a growing competitor to the tube amplifier comes now the Bell Laboratories’ transistor, a three-electrode germanium crystal of amazing amplification power, of wheat-grain size and low cost. Yet its frequency limitations, a few hundred "kilocycles, and its strict power limitations will never permit its general replacement of the Audion amplifier." – 1952
- "I came, I saw, I invented—it's that simple—no need to sit and think—it's all in your imagination."["citation needed]
Patent images in "TIFF format
- U.S. Patent 748,597 "Wireless Signaling Device" (directional antenna), filed December 1902, issued January 1904;
- U.S. Patent 824,637 "Oscillation Responsive Device" (vacuum tube detector diode), filed January 1906, issued June 1906;
- U.S. Patent 827,523 "Wireless Telegraph System" (separate transmitting and receiving antennas), filed December 1905, issued July 1906;
- U.S. Patent 827,524 "Wireless Telegraph System," filed January 1906 issued July 1906;
- U.S. Patent 836,070 "Oscillation Responsive Device" (vacuum tube detector – no grid), filed May 1906, issued November 1906;
- U.S. Patent 841,386 "Wireless Telegraphy" (tunable vacuum tube detector – no grid), filed August 1906, issued January 1907;
- U.S. Patent 841,387 "Device for Amplifying Feeble Electrical Currents" (...), filed August 1906, issued January 1907;
- U.S. Patent 876,165 "Wireless Telegraph Transmitting System" (antenna coupler), filed May 1904, issued January 1908;
- U.S. Patent 879,532 "Space Telegraphy" (increased sensitivity detector – clearly shows grid), filed January 1907, issued February 18, 1908;
- U.S. Patent 926,933 "Wireless Telegraphy";
- U.S. Patent 926,934 "Wireless Telegraph Tuning Device";
- U.S. Patent 926,935 "Wireless Telegraph Transmitter," filed February 1906, issued July 1909;
- U.S. Patent 926,936 "Space Telegraphy";
- U.S. Patent 926,937 "Space Telephony";
- U.S. Patent 979,275 "Oscillation Responsive Device" (parallel plates in "Bunsen flame) filed February 1905, issued December 1910;
- U.S. Patent 1,025,908 "Transmission of Music by Electromagnetic Waves";
- U.S. Patent 1,101,533 "Wireless Telegraphy" (directional antenna/direction finder), filed June 1906, issued June 1914;
- U.S. Patent 1,214,283 "Wireless Telegraphy."
- Lee De Forest in the "1900 US Census in "Milwaukee, Wisconsin
- Lee De Forest in the "1920 US Census in the "Bronx, New York
- Father of Radio: The Autobiography of Lee de Forest, 1950.
- The two Institutes merged in 1940 to become the "Illinois Institute of Technology "physics department.
- "Wireless Telegraphy That Sends No Messages Except By Wire", New York Herald, October 28, 1901, page 4.
- De Forest, page 126.
- "Cuss Words in the Wireless", New York Sun, August 27, 1903, page 1.
- A Modern Campaign: War and Wireless in the Far East by David Fraser, 1905.
- Inventing American Broadcasting: 1899-1922 by Susan J. Douglas, 1987, page 97.
- Wireless Communication in the United States: The Early Development of American Radio Operating Companies by Thorn L. Mayes, 1989, page 44.
- "Reporting Yacht Races by Wireless Telephony", Electrical World, August 10, 1907, pages 293–294.
- History of Communications-Electronics in the United States Navy by Captain L. S. Howeth, USN (Retired), 1963, "The Radio Telephone Failure", pages 169–172.
- "Barnard Girls Test Wireless 'Phones", New York Times, February 26, 1909, page 7.
- "Today in History, Jan 13". Retrieved 2008-06-24.
- The MetOpera Database (archives)
- "Radio Telephone Experiments", Modern Electrics, May, 1910, page 63.
- Father of Radio: The Autobiography of Lee de Forest, 1950, page 114. The notebook recordings of the 1900 experiments, including the determination that the flickering was due to sound only, are reproduced on this page.
- US 841387, De Forest, Lee, "Device for Amplifying Feeble Electrical Currents", issued 15 January 1907
- "What Everyone Should Know About Radio History: Part II" by J. H. Morecroft, Radio Broadcast, August, 1922, page 299: "[De Forest] took out a patent in 1905 on a bulb having two hot filaments connected in a peculiar manner, the intended functioning of which is not at all apparent to one comprehending the radio art."
- "The Audion: A New Receiver for Wireless Telegraphy" by Lee de Forest, Scientific American Supplement: No. 1665, November 30, 1907, pages 348–350 and No. 1666, December 7, 1907, pages 354–356.
- An alternate explanation was given by early associate Frank Butler, who stated that de Forest coined the term because the control electrode looked "just like a roaster grid". ("How the Term 'Grid' Originated", Communications magazine, December, 1930, page 41.)
- DeForest, page 322.
- "The Audion; A Third Form of the Gas Detector" by John L. Hogan, Jr., Modern Electrics, October, 1908, page 233.
- The Continuous Wave: Technology and American Radio, 1900-1932 by Hugh G. J. Aitken, 1985, pages 235–244.
- DeForest, page 327.
- Tyne, Gerald E. J. (1977). The Saga of the Vacuum Tube. Indianapolis, IN: Howard W. Sams & Company. pp. 119 and 162. "ISBN "0-672-21471-7.
- DeForest, page 340.
- Armstrong, Edwin H. "Edwin Armstrong: Pioneer of the Airwaves". Living Legacies. Columbia University. Retrieved 2015-10-30.
- Empire of the Air by Tom Lewis, 1991, pages 77, 87.
- Ibid., page 192.
- Ibid., pages 193–198, 203.
- Armstrong, Edwin H. "Biography". Encyclopædia Britannica. Encyclopædia Britannica. Retrieved 2015-10-30.
- Lewis, Tom (1991). Empire of the Air (first ed.). Harper Collins. pp. 218–219. "ISBN "0-06-018215-6.
- "Special Land Stations", Radio Service Bulletin, July, 1915, page 3. The "2" in 2XG's callsign indicated that the station was located in the 2nd Radio Inspection district, while the "X" signified that it held an Experimental license.
- De Forest, page 243. He noted that he had been "totally unaware of the fact that in the little audion tube, which I was then using only as a radio detector, lay dormant the principle of oscillation which, had I but realized it, would have caused me to unceremoniously dump into the ash can all of the fine arc mechanisms which I had ever constructed..."
- "Columbia Used to Demonstrate Wireless Telephone", The Music Trade Review, November 4, 1916, page 52.
- De Forest, page 337.
- Ibid., pages 337-338.
- "Election Returns Flashed by Radio to 7,000 Amateurs", The Electrical Experimenter, January, 1917, page 650.
- De Forest, page 350.
- "'Broadcasting' News by Radiotelephone" (letter from Lee de Forest), Electrical World, April 23, 1921, page 936.
- The initial advertisements for Radio News & Music, Inc., appeared on page 20 of the March 13, 1920 The Fourth Estate, and page 202 of the March 18, 1920 Printers' Ink.
- Lee de Forest and Phonofilm at Virtual Broadway website
- Randy Alfred, Wired magazine (March 12, 2008)
- ASCE website entry
- "Auto Interests Buy DeForest Radio Co.," The New York Times, April 6, 1923, page 19.
- "'Magnificent Failure'" by Samuel Lubell, Saturday Evening Post, January 31, 1942, page 49).
- "Robot Television Bomber" Popular Mechanics June 1940
- Highlights of this episode, as well as a film clip of his 1940 NAB letter, are included in the 1992 "Ken Burns PBS documentary "Empire of the Air: The Men Who Made Radio.
- Empire of the Air: The Men Who Made Radio. PBS: 1992.
- "Lee De Forest, 87, Radio Pioneer, Dies; Lee De Forest, Inventor, Is Dead at 87". New York Times. July 2, 1961.
"Hollywood, California, July 1, 1961. Dr. Lee De Forest, the inventor known as the father of radio, died last night at his home. He was 87 years old.
- Empire of the Air: The Men Who Made Radio
- Quantum Generations: A History of Physics in the Twentieth Century by Helge Kragh, 2002, page 127: "...De Forest's invention of the triode (or "audion") was the starting point of the electronic age."
- Dawn of the Electronic Age by Frederick Nebeker, 2009, page 15: "The triode vacuum-tube is one of the small number of technical devices... that have radically changed human culture. It defined a new realm of technology, that of electronics..."
- Millard, Max (October 1993). "Lee de Forest, Class of 1893:Father of the Electronics Age". Northfield Mount Hermon Alumni Magazine. Retrieved 2011-01-20.
- "The Perham Collection". History San José. 2011. Archived from the original on April 26, 2015. Retrieved March 22, 2016.
- IEEE Global History Network (2011). "IEEE Medal of Honor". IEEE History Center. Retrieved 7 July 2011.
- The 32nd Academy Awards: Memorable Moments.
- Hollywood Walk of Fame: Lee De Forest.
- James A. Hijya, Lee De Forest and the Fatherhood of Radio (1992), Lehigh University Press, pages 119-120
- Campbell, Richard, Christopher R. Martin, and Bettina Fabos. "Sounds and Images." Media and Culture: An Introduction to Mass Communication. Boston: Bedford/St. Martin's, 2000. 113, additional text.
- "Dawn of the Electronic Age". "Popular Mechanics. January 1952. Retrieved 2007-07-21.
- Gawlinski, Mark (2003). Interactive television production. Focal Press. p. 89. "ISBN "0-240-51679-6.
- De Forest Says Space Travel Is Impossible, Lewiston Morning Tribune via Associated Press, February 25, 1957
- The Continuous Wave: Technology and American Radio, 1900-1932 by Hugh G. J. Aitken, 1985.
- "'Magnificant Failure'" by Samuel Lubell, Saturday Evening Post, three parts: January 17, 1942 (pages 9–11,75–76, 78, 80), January 24, 1942 (pages 20–21, 27–28, 38, and 43), and January 31, 1942 (pages 27, 38, 40-42, 46, 48–49).
- "De Forest and the Triode Detector" by Robert A. Chipman, Scientific American, March, 1965, pages 93–101.
- Saga of the Vacuum Tube by Gerald E. J. Tyne (Indianapolis, IN: Howard W. Sams and Company, 1977). Tyne was a research associate with the "Smithsonian Institution. Details de Forest's activities from the invention of the Audion to 1930.
- Empire of the Air: The Men Who Made Radio by "Ken Burns a PBS Documentary Video 1992. Focuses on three of the individuals who made significant contributions to the early radio industry in the United States: De Forest, "David Sarnoff and "Edwin Armstrong. LINK
- A History of the Regeneration Circuit: From Invention to Patent Litigation by Prof. Sungook Hong, University, Seoul, Korea, 2004 (treatise on the regeneration controversy)
|""||Wikiquote has quotations related to: Lee de Forest|
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- Lee de Forest, American Inventor
- Dr. Lee De Forest internet radio project & forum
- Lee de Forest at the "Internet Movie Database
- Lee De Forest at "IEEE
- Lee De Forest at "National Inventors Hall of Fame
- on "YouTube
- Stephen Greene's Who said Lee de Forest was the "Father of Radio"?
- Eugenii Katz's Lee De Forest
- Cole, A. B., "Practical Pointers on the Audion: Sales Manager – De Forest Radio Tel. & Tel. Co.," QST, March, 1916, pages 41–44:
- Hong, Sungook, "A History of the Regeneration Circuit: From Invention to Patent Litigation" University, Seoul, Korea (PDF)
- "PBS, "Monkeys"; a film on the Audion operation ("QuickTime movie)
- "De Forest, Lee". The Cyclopædia of American Biography. 1918.
- Adams, Mike, Lee de Forest and the Invention of Sound Movies, 1918-1926, "The AWA Review (vol. 26, 2013).
- Historic photograph 1924. "De Forest Phonofilm Co. Inc. on White House grounds."