George R. Carey
Encyclopedia
George R. Carey was an American inventor born in 1851. He was among the first to propose the telectroscope
using the photo-electric properties of selenium
as a means for transmitting images - a precursor to modern television
.
George R. Carey was a professional surveyor
employed by the City of Boston
.
In 1873, Willoughby Smith
had discovered that the amount of electrical current that selenium conducted depended on the amount of light that struck it. (This property of certain conducting materials is called photoconductivity
.)
George R. Carey learned of this discovery and used it to devise a crude system for transmitting images - an early attempt at television.
In the May 17, 1878 issue of Scientific American
, the editors alluded to their earlier article about the 'telectroscope invented by M. Senlecq
of Ardres.' This was followed by the news that they had before them 'some very ingenious and curious applications of selenium, in which its peculiar property of changing its electrical conductivity when exposed to light varying in intensity is utilized. The several devices are the invention of Mr. George R. Carey, of Boston, Mass.' A more detailed article was published in the June 5, 1880 Scientific American.
The Scientific American article described two different inventions.
The first used an array of selenium photocells and wires to transmit an image to an array of light, which were then used to expose a piece of photographic paper. The photograph could then be developed to create a single image.
The second invention used a large array of photocells and wires to transmit the signal to a visual display made of many individual lights. Although this approach should work in theory, each individual pixel requires its own photocell and wired circuit, making this system cumbersome and expensive for producing even a modest size image.
Carey was sometimes credited with making his invention as early as in 1875. However, he himself wrote that he only had an idea for his invention a year later. Neither does it seem probable that his invention was the inspiration for the supposedly fake
"Electroscope" described in the March 29, 1877 issue of the New York Sun
.
Telectroscope
thumb|200px|right|Telectroscope technical illustration in [[Scientific American]] Supplement No. 275, April 9, 1881The telectroscope was the first non-working prototype of a television or videophone system...
using the photo-electric properties of selenium
Selenium
Selenium is a chemical element with atomic number 34, chemical symbol Se, and an atomic mass of 78.96. It is a nonmetal, whose properties are intermediate between those of adjacent chalcogen elements sulfur and tellurium...
as a means for transmitting images - a precursor to modern television
Television
Television is a telecommunication medium for transmitting and receiving moving images that can be monochrome or colored, with accompanying sound...
.
George R. Carey was a professional surveyor
Surveying
See Also: Public Land Survey SystemSurveying or land surveying is the technique, profession, and science of accurately determining the terrestrial or three-dimensional position of points and the distances and angles between them...
employed by the City of Boston
Boston
Boston is the capital of and largest city in Massachusetts, and is one of the oldest cities in the United States. The largest city in New England, Boston is regarded as the unofficial "Capital of New England" for its economic and cultural impact on the entire New England region. The city proper had...
.
In 1873, Willoughby Smith
Willoughby Smith
Willoughby Smith was an English electrical engineer who discovered the photoconductivity of the element selenium...
had discovered that the amount of electrical current that selenium conducted depended on the amount of light that struck it. (This property of certain conducting materials is called photoconductivity
Photoconductivity
Photoconductivity is an optical and electrical phenomenon in which a material becomes more electrically conductive due to the absorption of electromagnetic radiation such as visible light, ultraviolet light, infrared light, or gamma radiation....
.)
George R. Carey learned of this discovery and used it to devise a crude system for transmitting images - an early attempt at television.
In the May 17, 1878 issue of Scientific American
Scientific American
Scientific American is a popular science magazine. It is notable for its long history of presenting science monthly to an educated but not necessarily scientific public, through its careful attention to the clarity of its text as well as the quality of its specially commissioned color graphics...
, the editors alluded to their earlier article about the 'telectroscope invented by M. Senlecq
Constantin Senlecq
Constantin Senlecq was a French scientist and inventor who is credited with the invention of telectroscope. He worked independently of the American inventor George R. Carey , who came up with a similar idea at approximately the same time .Telectroscope was the first prototype television...
of Ardres.' This was followed by the news that they had before them 'some very ingenious and curious applications of selenium, in which its peculiar property of changing its electrical conductivity when exposed to light varying in intensity is utilized. The several devices are the invention of Mr. George R. Carey, of Boston, Mass.' A more detailed article was published in the June 5, 1880 Scientific American.
The Scientific American article described two different inventions.
The first used an array of selenium photocells and wires to transmit an image to an array of light, which were then used to expose a piece of photographic paper. The photograph could then be developed to create a single image.
The second invention used a large array of photocells and wires to transmit the signal to a visual display made of many individual lights. Although this approach should work in theory, each individual pixel requires its own photocell and wired circuit, making this system cumbersome and expensive for producing even a modest size image.
Carey was sometimes credited with making his invention as early as in 1875. However, he himself wrote that he only had an idea for his invention a year later. Neither does it seem probable that his invention was the inspiration for the supposedly fake
Telectroscope
thumb|200px|right|Telectroscope technical illustration in [[Scientific American]] Supplement No. 275, April 9, 1881The telectroscope was the first non-working prototype of a television or videophone system...
"Electroscope" described in the March 29, 1877 issue of the New York Sun
New York Sun
The New York Sun was a weekday daily newspaper published in New York City from 2002 to 2008. When it debuted on April 16, 2002, adopting the name, motto, and masthead of an otherwise unrelated earlier New York paper, The Sun , it became the first general-interest broadsheet newspaper to be started...
.