Ct scanner comprising a spatially encoded detector array arrangement and method

Abstract

A CT scanner comprising a spatially encoded detector arrangement for providing data values representing variable thickness slices, and a method of efficiently detecting X-rays for variable thickness slices of a CT scanner are disclosed. The spatially encoded detector arrangement includes a plurality of columns of detector elements, with the detector elements of each column being distributed and arranged so that the lengths of at least some of the detector elements of each of the columns vary in accordance with a predetermined sequence code that represents all of the whole integer values in equal increments from 1 to N, wherein N is a whole integer greater than 1, and preferably greater than 3. Preferably, the sequence code is a biquinary code of 5, 2, 2, 1 so that N is at least 10. The detector arrangement is preferably a 2D array having rows of two or more lengths so that beams of various thicknesses each can be projected onto a row or rows of detector elements having a detection area substantially matched to the corresponding beam. The spatial encoding using the sequence code preferably also allows for one or more sets of multiple slices of equal thickness to be simultaneously generated. By spatially encoding the array with the sequence code, the number of detector elements can be reduced from an array made of detector elements of equal length, i.e., the number of detector elements of each column representing the code is less than N, and more efficient X-ray conversion achieved.