Quarles & Brady
Whole-body dual-energy bone densitometry using a narrow angle fan beam to cover the entire body in successive scans
 A scanning radiographic densitometer constructs a broad area, two dimensional projection image from a combination of a set of smaller fan beam scans by tilting the axis of each such smaller scan to construct an effective larger fan beam to reduce artifacts caused by height dependant overlap of the multiple fan beams. The data is projected to a non-planar image surface to eliminate local area distortion such as may cause error in density measurements and to permit some overlap without height sensitive effects. 
Lunar Corporation
Joseph P. Richard B. Jixing
Bisek Mazess Chen