The optical designs of three CCD cameras for the Keck Observatory spectrometers are described and illustrated with drawings and diagrams. The 8-element camera for the Low-Resolution Imaging Spectrometer (LRIS) has focal length 12.0 inches, entrance aperture 8.9 inches, and flat FOV diameter 2.93 inches; the camera is color corrected without refocusing over the spectral range 390-1000 nm. For the High-Resolution Echelle Spectrometer (HIRES), a larger and a smaller version of a 30-inch-focal-length camera have been designed. Each camera is color corrected at 310-1100 nm and comprises a single-element corrector, a concave mirror, a contact triplet field-flattening element, and a flat vacuum window. The smaller design, with 28.7-inch entrance aperture and flat FOV diameter 3.15 inches, has been selected for construction.
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