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Land Cameras are instant cameras with self-developing film named after their inventor, Edwin Land, while working for Research Row in Boston, Massachusetts〔 ("Trillion Dollar Mile of Brain." ) ''Popular Mechanics'', July 1952, pp. 129-133/222〕 and manufactured by Polaroid between the years of 1947 and 1983.〔(Why are they named Land cameras--the Landlist.org )〕 Though Polaroid continued producing instant cameras after 1983, the name 'Land' was dropped from the camera name since Edwin Land retired in 1982.〔(A Polaroid history timeline )〕 The first commercially available model was the ''Polaroid Land Camera Model 95'',〔(Polaroid cameras and photography )〕 which produced prints in about 1 minute,〔(Talktalk article on "Polaroid Camera" )〕and was first sold to the public in November, 1948.〔(Edwin Land - Polaroid Photography - Instant Photography )〕 ==Film== The process, invented by Polaroid founder Edwin Land, was to employ diffusion transfer to move the dyes from the negative to the positive via a reagent. A negative sheet was exposed inside the camera, then lined up with a positive sheet and squeezed through a set of rollers which spread a reagent between the two layers, creating a developing film sandwich. The negative developed quickly, after which some of the unexposed silver halide grains (and the latent image it contained) were solubilized by the reagent and transferred by diffusion from the negative to the positive. After a minute, the back of the camera was opened and the negative peeled away to reveal the print. In 1963, Land introduced ''Polacolor'' pack film, which made instant color photographs possible. This process involved pulling two tabs from the camera, the second which pulled the film sandwich through the rollers to develop out of the camera. The instant colour process is much more complex, involving a negative which contains three layers of emulsion sensitive to blue, green, and red. Underneath each layer are dye developing molecules in their complementary colours of yellow, magenta, and cyan. When light strikes an emulsion layer, it blocks the complementary dye below it. For instance, when blue strikes the blue sensitive emulsion layer, it blocks the yellow dye, but allows the magenta and cyan dyes to transfer to the positive, which combine to create blue. When green and red (yellow) strikes their respective layers, it blocks the complementary dyes of magenta and cyan below them, allowing only yellow dye to transfer to the positive. In 1972, integral film was introduced which did not require the user to time the development or peel apart the negative from the positive. This process was similar to polacolor film with added timing and receiving layers. The film itself integrates all the layers to expose, develop, and fix the photo into a plastic envelope commonly associated with a Polaroid photo. The Polaroid SX-70 camera was the first to utilize this film. Improvements in SX-70 film led to the higher speed 600 series film, then to different formats such as 500 series (captiva), and spectra. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Land Camera」の詳細全文を読む スポンサード リンク
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