Limitations to the spatial resolution of current digital x-ray systems are bounded by the physical characteristics of the xray
detector. However, the need to image smaller structures provides motivation to develop high-resolution x-ray
detector systems for use with computed radiographic, and tomographic x-ray systems. We report the implementation of
a tilted detector technique (TDT) to attain near isotropic resolution enhancement by combining two orthogonal image
views, acquired with existing detector hardware tilted at a fixed angle.
Images were acquired using a ceiling-mounted x-ray unit (Proteus XR/a, GE Medical Systems, 50kVp, 250mAs).
Images were digitized using a Fujifilm Capsula X CR system, from a 35×43cm detector cassette placed on an angulated
stand, featuring a 3520×4280 image matrix with an in-plane pixel spacing of 0.1mm. Three images were acquired: two
for use with our TDT; and one for comparison, with no detector tilt. Performance was determined by using two line-pair
phantoms (Models 07-521 and 07-533, Nuclear Associates) placed orthogonally to each other in the field of view.
Custom software corrected for perspective distortion, co-registered and combined the tilted-detector images into a single
Following unwarping and co-registration, the limiting spatial resolution of an image obtained via the weighted
combination of the two orthogonal views (8 lp/mm) is found to be superior to that of a single view acquired with no
detector tilt (5 lp/mm).
This novel technique shows significant improvement in the spatial resolution of x-ray image acquisitions, using existing
x-ray components and detector hardware.