Ucl Business Plc

Alessandro Olivo

Robert Speller

Fabio Alessio Vittoria

Konstantin Ignatyev

Marco Endrizzi

Peter Munro

Paul Diemoz

Thomas Millard

Charlotte Hagen

Robert D Speller

Fabio Vittoria

A computed tomography method seeking higher resolutions without imposing a dose increase is described. A mask () forms a plurality of X-ray beam lets () which are passed through a subject (), and images are captured on X-ray detector (). The subject () is moved with respect to the X-ray detector and mask, including a rotation around a y axis, and a computed tomography image is reconstructed from the plurality of measured datapoints. The beam lets () are of small size. FIGS.-are blurred, FIGS.andcontain too small letters/numbers.

Computed tomography imaging

A method of X-ray imaging includes passing an X-ray beam through a pre-sample maskwith a plurality of apertures, through a sample, and then through a detector maskwith aligned apertures. The beams are detected. The detector maskand pre-sample maskare moved with respect to one another to identify the position of maximum intensity and then moved to two further positions on equal and opposite spacings on either side of the maximum. Images are acquired and a transmission image, refraction image and scattering image calculated.

Coded-aperture X-ray imaging

A method of aligning masks for phase imaging or phase contrast imaging in X-ray apparatus using a pixel-type X-ray detector makes use of non-idealities of all real detectors. A mask may be provided before the sample to generate beams, adjacent to the pixels of the detector or both. The method includes moving the mask into a plurality of translational position increments and identifying the increment for which the intensity has a maximum or minimum. The identified value of the increment may vary over the pixels of the detector. Alignment positions are selected in which steps in a plot of the increment over the area of the detector are minimized and/or aligned with the rows and columns of pixels.

X-ray imaging

A method of phase imaging uses X-ray beams having edges overlapping with pixels. A phase image may be obtained from first and second images using one or more X-ray beam, the first image being measured with the first edge but not the second edge of each X-ray beam overlapping the corresponding pixel(s) and the second image being measured with the second edge but not the first edge overlapping the corresponding pixel(s). The gradient of the X-ray absorption function may be calculated and a proportional term included in the image processing to calculate a quantitative phase image.

Phase imaging

Phase contrast imaging is achieved using a sample maskand a detector mask (). X-rays emitted from x-ray source () are formed into individual beams () by sample mask which pass through sample () and arrive at individual pixels () of the detector () through detector mask (). The individual x-ray beams are arranged to hit the pixel edge () of individual rows of pixels, individual columns of pixels or individual pixels. Small deviations &#x3b8; in the individual beams () cause a significant increase or decrease in the signal hitting the exposed area () of the pixel resulting in a significant phase contrast signal.

Growing community of inventors

London, United Kingdom

Alessandro Olivo