File:Flying spot scanner television studio 1931.png
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Summary
| Description |
English: Drawing of an early television studio in the 1930s using mechanical flying spot scanner television cameras, owned by the Jenkins Television Co. During the 1920s and 30s, before modern electronic-scanning television systems debuted around 1940, dozens of experimental stations broadcast television programs using mechanical scanning technology. Instead of a television camera that recorded an image, a powerful light source called a "flying spot scanner" (bottom) projects a moving spot of intense light onto the subject (top) in the darkened studio. A spinning disk in the scanner pierced with small holes, called a Nipkow disk, scans the light beam across the subject in a raster pattern. The light reflected off the subject by the spot is picked up by banks of photo cells near the subject. The photo cells produce a varying signal proportional to the brightness of the spot on the subject where the beam strikes. This becomes the video signal broadcast by the transmitter (left). To the left is also visible a television movie projection camera, used for broadcasting movies from film. Alterations to image: Added label "NIPKOW DISK" to flying spot scanner, and "PHOTO CELLS" to second bank of photocells that weren't labelled. |
| Date | |
| Source | Retrieved March 20, 2014 from Delbert E. Replogle, "The Jenkins New York Studio" in Television News magazine, Popular Book Corp., New York, Vol. 1, No. 3, July-August 1931, p. 170 on AmericanRadioHistory.com website. |
| Author | Delbert E. Replogle |
| Permission (Reusing this file) |
This 1931 issue of Television News magazine would have the copyright renewed in 1959. Online page scans of the Catalog of Copyright Entries, published by the US Copyright Office can be found here. [1] Search of the Renewals for Periodicals for 1958, 1959, and 1960 show no renewal entries for Television News. Therefore the magazine's copyright was not renewed and it is in the public domain. |
Licensing
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This work is in the public domain because it was published in the United States between 1929 and 1963, and although there may or may not have been a copyright notice, the copyright was not renewed. For further explanation, see Commons:Hirtle chart and the copyright renewal logs. Note that it may still be copyrighted in jurisdictions that do not apply the rule of the shorter term for US works (depending on the date of the author's death), such as Canada (70 years p.m.a.), Mainland China (50 years p.m.a., not Hong Kong or Macao), Germany (70 years p.m.a.), Mexico (100 years p.m.a.), Switzerland (70 years p.m.a.), and other countries with individual treaties.
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| Date/Time | Thumbnail | Dimensions | User | Comment | |
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| current | 20:34, 12 August 2014 | | 1,104 × 788 (182 KB) | Chetvorno | User created page with UploadWizard |
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