4" diameter silicon wafer containing 2048 x 4096 CCD Imager (15um pixel) for the Keck telescope, and prototype imagers for SNAP (1294 x 4186, 12um pixel and 1478 x 4784, 10.5um pixel). A charge-coupled device (CCD) is a device for the movement of electrical charge, usually from within the device to an area where the charge can be manipulated, for example conversion into a digital value. The CCD is a major piece of technology in digital imaging. In a CCD image sensor, pixels are represented by p-doped MOS capacitors. Although CCDs are not the only technology to allow for light detection, CCD image sensors are widely used in professional, medical, and scientific applications where high-quality image data is required. The W. M. Keck Observatory is a two-telescope astronomical observatory at an elevation of 13,600 feet near the summit of Mauna Kea in Hawaii. Both telescopes feature 33 foot primary mirrors, currently among the largest astronomical telescopes in use. The combination of an excellent site, large optics and innovative instruments has created the two most scientifically productive telescopes on Earth.