Range estimation from focus using a non-frontal imaging camera

This paper is concerned with active sensing of range information from focus. It describes a new type of camera whose sensor plane is not perpendicular to the optical axis as is standard. This special imaging geometry eliminates sensor plane movement usually necessary for focusing. Camera panning, required for panoramic viewing anyway, in addition enables focusing and range estimation. Thus panning integrates the two standard mechanical actions of focusing and panning, implying range estimation is done at the speed of panning. An implementation of the proposed Non-frontal Imaging Camera (NICAM) design is described. Experiments on range estimation are also presented.The support of the National Science Foundation and Defense Advanced Research Projects Agency under grant IRI-89-02728 and U.S. Army Advance Construction Technology Center under grant DAAL 03-87-K-0006 is gratefully acknowledged.