Lunar Reconnaissance Orbiter Wide-Angle Camera (LROC WAC)
The Lunar Reconnaissance Orbiter Camera's Wide-Angle Camera is a small instrument, weighing only 900 grams. It is a pushframe imager with five visible channels and two ultraviolet channels. It maps the whole Moon every month. At an altitude of 50 kilometers, it achieves 74.9 meters per pixel in visible wavelengths and 383.5 meters per pixel int he ultraviolet. Monochrome visible images are 1024 pixels wide (104.6 kilometers from a 50-kilometer altitude). Color images are 704 pixels wide (59.6 kilometers from a 50-kilometer altitude).
LROC WAC has two optical paths, one for ultraviolet and one for visible. Light passing through the optics is focused on a single detector. Color filters are bonded directly to the detector. One image frame is an exposure of the entire array. The frame consists of seven framelets, each one corresponding to a different filter wavelength. The design of the LROC WAC color filter array is very similar to that of Mars Reconnaissance Orbiter MARCI, except for slightly different choices of wavelengths.