Edison_effect_bulb_1.jpg
Summary
Description Edison effect bulb 1.jpg |
English:
One of the bulbs
Thomas Alva Edison
used to discover
thermionic emission
(the Edison Effect) in 1884. It consists of an Edison incandescent lamp - an evacuated glass bulb with a hairpin shaped bamboo carbon
filament
- with an additional platinum foil electrode
(center, inside the filament)
connected to wire terminals. A current is applied to the filament, heating it. Edison found when he connected an ammeter between the filament and the auxiliary electrode, a current would flow, passing through the evacuated space of the bulb from filament to electrode. This current was later found to consist of
electrons
. This effect is the basis of
vacuum tube
technology, which dominated electronics for 50 years, until the 1970s.
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Date |
before 1922
date QS:P,+1922-00-00T00:00:00Z/7,P1326,+1922-00-00T00:00:00Z/9
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Source | Downloaded August 17, 2013 from Clayton H. Sharp (January 1922) The Edison Effect and its Modern Applications , Journal of the AIEE, Vol. 41, No. 1, American Institute of Electrical Engineers, New York, p. 69, fig. 2, 10-c on Google Books |
Author | Clayton H. Sharp |
Licensing
Public domain Public domain false false |
This media file is in the
public domain
in the
United States
. This applies to U.S. works where the copyright has expired, often because its first
publication
occurred prior to January 1, 1929, and if not then due to lack of notice or renewal. See
this page
for further explanation.
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This image might not be in the public domain outside of the United States; this especially applies in the countries and areas that do not apply the
rule of the shorter term
for US works, such as Canada, Mainland China (not Hong Kong or Macao), Germany, Mexico, and Switzerland. The creator and year of publication are essential information and must be provided. See
Wikipedia:Public domain
and
Wikipedia:Copyrights
for more details.
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