Necessity is often the mother of invention. But the key technology behind the digital camera and the camcorder was developed for a completely different application, and its inventors weren't even sure what to make of their creation.

It was early October 1969. Dr. Willard Boyle and Dr. George Smith, physicists in the Semiconductor Components Division at Bell Labs were researching new memory chip concepts for data storage. One of these methods was the hot technology prospect of the day, Magnetic Bubbles, which could capture and transmit digital information by moving bubbles of magnetism around on various surfaces. Not only were they hoping for a breakthrough, they needed a breakthrough or funding for their work would be funneled to other projects.

In a brain-storming session, Smith, who also was working on Bell's PicturePhone technology, and Boyle, decided to ask each other a series of "what if" questions and jotted the varying approaches on a blackboard. After many sketches and erases, the pair ended up designing a silicon circuit device that stored information represented by discrete packets of electric charges in columns of closely spaced semiconductor capacitors, which stored the appropriate electric charge. With multiple columns side by side, their device could transform light into electrical information, record that information and then reconstruct and reproduce the information by shifting the stored charges down the columns, one position at a time. By the time lunch rolled around, the pair had created the device's basic structure, principles of operation and possible applications. Smith realized that the thingamajig could be used not only for data storage but could improve the video camera in the PicturePhone. But what to call it?

Because the device moved an electrical charge around by coupling potential wells, Boyle suggested "charge coupled device," or CCD. In short order, the pair wrote up their invention in a paper, published in the Bell System Technical Journal on January 29, 1970. They later presented the CCD at a conference in New York on the future of integrated circuits and completely changed the course of image capture and reproduction.

Smith and Boyle built the first solid state digital video recorder in their labs in 1970, but the pair were not product developers. And their CCD was monochrome only. Several companies including Texas Instruments, RCA and Fairchild began developing color image sensors. In 1975, Kodak researcher Kenneth A. Parulski led the successful development of a color CCD, which added red, green and blue filters to the monochrome CCD during the last phase of fabrication.

Some digital cameras don't use CCDs but an imaging technology based on CMOS (complementary metal-oxide-semiconductor) circuits, invented in 1963 by Frank Wanlass at Fairchild Semiconductor and made by RCA in 1968 by a group led by Albert Medwin.