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A Charge Coupled Device (CCD) is a computer chip used to convert light entering a camera into an electronic image. The size is measured diagonally is most often 1/4", 1/3", or 1/2" inches. There are two types, frame transfer and interline transfer. It operates by converting light energy into an electrical charge.
A CCD consists of several hundred thousand individual picture elements (pixels) on a tiny 1/2", 1/3", or 1/4" chip. Each pixel responds to light falling on it by storing a tiny charge of electricity. The pixels are arranged on a precise grid, with vertical and horizontal transfer registers carrying the signals to the camera's video processing circuitry. This transfer of signals occurs sixty times per second. The CCD camera's electronic shutter is not really a moving shutter, but a clever piece of signal processing. Under low light conditions, the CCD is allowed to gather signal for the full 1/60th of a second. Under brighter lighting conditions, the video processing chip automatically responds by reading the CCD and then immediately "early purging" it, resulting in precise control over the video level. Even at a shutter speed of 1/100,000 of a second, the CCD camera is still delivering 60 images per second, but each image is gathered over a much shorter period of time. It doesn't end with the CCD...the image is constantly monitored and optimised by advanced on board signal processing circuitry. The end result is a fantastic picture, with no fiddling, no adjustments, and best of all, unbelievable reliability.