The first recorded attempt at building a digital camera was in 1975 by Steven Sasson, an engineer at Eastman Kodak.[1][2] It used the then-new solid-state CCD image sensor chips developed by Fairchild Semiconductor in 1973.[3] The camera weighed 8 pounds (3.6 kg), recorded black and white images to a cassette tape, had a resolution of 0.01 megapixels (10,000 pixels), and took 23 seconds to capture its first image in December 1975. The prototype camera was a technical exercise, not intended for production.
The first true digital camera that recorded images as a computerized file was likely the Fuji DS-1P of 1988, which recorded to a 16 MB internal memory card that used a battery to keep the data in memory. This camera was never marketed in the United States, and has not been confirmed to have shipped even in Japan.
The first commercially available digital camera was the 1990 Dycam Model 1; it also sold as the Logitech Fotoman. It used a CCD image sensor, stored pictures digitally, and connected directly to a computer for download.[4][5][6]
The first flyby spacecraft image of Mars was taken from Mariner 4 on July 15, 1965 with a camera system designed by NASA/JPL. It used a video camera followed by a digitizer, rather than a mosaic of sensor elements, so it was not what we usually define as a digital camera, but it produced a digital image that was stored on tape for later slow transmission back to earth.[7][8]
[edit]Sensors and storage
Image sensors read the intensity of light, and digital memory devices store the digital image information as RGB color space or as raw data.
The two main types of sensors are charge-coupled devices, in which the photocharge is shifted to a central charge-to-voltage converter, and CMOS or active pixel sensors.
Nearly all digital cameras use built-in and/or removable solid state flash memory. Digital tapeless camcorders that double as a digital still cameras use flash memory, discs and internal hard drives. Certain 20th century digital cameras such as the Sony Mavica range used floppy disks and mini-CDs.
[edit]Multifunctionality and connectivity
Except for some linear array type of cameras at the highest-end and simple web cams at the lowest-end, a digital memory device (usually a memory card; floppy disks and CD-RWs are less common) is used for storing images, which may be transferred to a computer later.
Digital cameras can take pictures, and may also record sound and video. Some can be used as webcams, some can use the PictBridge standard to connect to a printer without using a computer, and some can display pictures directly on a television set. Similarly, many camcorders can take still photographs, and store them on videotape or on flash memorycards with the same functionality as digital cameras.
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