Millimeter-wave imaging has recently become a vigorous research area because of its demonstrated ability to see under a variety of adverse environmental conditions, such as fog, clouds, snow, smoke, rain, etc., as well as through walls, w x doors, and most common clothing materials 1᎐4 . Among the civilian applications being developed for imaging in this spectral range are contraband and concealed weapon detection, through-wall imaging, surveillance within buildings, remote forest-fire detection, underground metal detection, lowvisibility autonomous landing of aircrafts, and many more.For short-range applications, both active and passive imaging systems are being perfected. In active imaging, the object is illuminated with a source of millimeter waves, and a large lens or a focusing mirror is used to form an image of the object with the power reflected by it. In passive imaging, the electromagnetic power is thermally emitted by the object, and a focusing element forms an image of it. For longrange applications, mostly passive imaging systems are being developed.Once the image is formed, either actively or passively, there are several methods for acquiring it. Early systems used single detectors at the focal plane, the detector being mechanically scanned across the scene of interest. Due principally to the slow mechanical scan motion, these systems took tens of minutes to take single-frame images. The present goal in millimeter-wave imaging research is to drastically reduce the image acquisition time in order to approach TV frame rates. One of the important approaches being investigated to reach this goal is the use of focal plane solid-state arrays with individualized amplification and detection. The other important approach is the combination of raster motion and a single receiver channel. The raster motion is either of the image in front of a fixed receiver by means of a flapping w x reflector 1, 5 or of the receiver in front of a fixed image w x 3, 6 .Although millimeter-wave imaging may be mostly dominated in the future by focal plane arrays, there are, however, several problems associated with them, like high cost, large Contract grant sponsor: CONACYT Contract grant number: 25789-A size, cryogenic cooling, complexities associated with interw x channel gain stability, and others 1, 3 , so that, as present, the field remains dominated by scanned systems; however, their success awaits the discovery of a compact and efficient w x scanner capable of achieving video rates 3 .In this work, we propose a new scheme for raster-scanned image acquisition in which neither the image nor the single channel receiver has to be scanned, and whose maximum frame rate will be determined ultimately by the speed and sensitivity of the single-channel receiver, and not by mechanical-motion limitations. The two principal components in this new scheme are a Nipkow disk and an integrating sphere. The Nipkow disk, which is utilized for scanning, is provided with a number of spirally distributed sampling apertures. Historically, it was ...