Imaging of materials

• US 20080237480A1
• Filed: 03/28/2008
• Published: 10/02/2008
• Est. Priority Date: 03/29/2007
• Status: Active Grant

• Current Assignee: Kromek Limited (Kromek Group PLC)
• Original Assignee: Durham Scientific Crystals Limited
• Inventors: Robinson, Max
• Granted Patent: US 7,656,995 B2
• Time in Patent Office: Days
• US Class Current: 250/370.09
• CPC Class Codes: G01V 5/228 using stereoscopic means

Abstract

An apparatus and method for obtaining an image of an object. The apparatus comprises a radiation source and a series of two to five linear detectors spaced therefrom to define a scanning zone; means to cause an object to move relative to and through the scanning zone; a direct image generation apparatus to generate an image from the output of a linear detector; an intermediate image generation apparatus configured to generate at least one intermediate image from an adjacent pair of linear detectors, by processing the output of the pair of detectors and generating an image representative of an output intermediate between the two said detector outputs; the image apparatus adapted such that at least five and preferably at least six images are generated in total; an image display adapted successively to display such images and thus display the monocular movement parallax between the images.

Claims

1. An apparatus for generating and displaying an image of an object comprising:

a radiation source and a series of at least two and no more than five linear radiation detectors spaced therefrom to define a scanning zone therebetween;

means to cause an object to move relative to and through the scanning zone in use;

a direct image generation apparatus to generate an image from the output of at least one linear detector;

an intermediate image generation apparatus configured to generate at least one intermediate image from at least one adjacent pair of linear detectors, by processing the output of said pair of detectors and generating an image representative of an output intermediate between the two said detector outputs;

the image generation apparatus adapted such that at least five images are generated in total;

an image display adapted successively to display such images and thus display the monocular movement parallax between the images.

2. An apparatus in accordance with claim 1 wherein the linear detectors making up the laterally spaced series are arranged such that the distance between them changes in order to maintain a constant angular separation between each array.

3. An apparatus in accordance with claim 2 further comprising alignment means to allow for alignment of each linear detector.

4. An apparatus in accordance with claim 1 the apparatus comprises a collimator adapted to allow a user to select two to five beams from a single radiation source.

5. An apparatus in accordance with claim 1 comprising a laterally spaced series of at least three but no more than five linear detectors and an image generation apparatus adapted to generate a series of at least six images for successive display.

6. An apparatus in accordance with claim 1 wherein the image display is a monocular display adapted successively to display images as individual two-dimensional images.

7. An apparatus in accordance with claim 6 wherein the image display is a two dimensional video display screen.

8. An apparatus in accordance with claim 1 wherein the intermediate image generator is configured to generate two or more intermediate images from at least one adjacent pair of detectors which show a gradual transition between the images produced by the adjacent pair of detectors by processing the output of the pair of detectors and generating image representatives of a transition between the two said detected outputs.

9. An apparatus in accordance with claim 1 further comprising control means to enable a user to display successive images at variable speeds in order to enable a smooth transition for the human observer between each image and/or in a forward and reverse order.

10. An apparatus in accordance with claim 1 wherein each linear detector in the laterally spaced series comprises a linear array of photodiode cells.

11. An apparatus in accordance with claim 1 wherein at least some of the linear detectors comprise dual energy detectors.

12. An apparatus in accordance with claim 1 wherein at least some of the linear detectors comprise detectors that can generate spectroscopic information about the transmitted radiation, in that the detector exhibits a spectroscopically variable response across at least a substantial part of the source spectrum allowing spectroscopic information to be retrieved.

13. An apparatus in accordance with claim 12 including image processing means adapted to represent spectroscopic resolution of the source spectrum in the generated image.

14. An apparatus in accordance with claim 13 wherein the image processing means is adapted to process the spectroscopically resolved data into a plurality of bands and apply different colours to represent each such band in the generated image.

15. An apparatus in accordance with claim 1 wherein the linear detector exhibits a direct spectroscopic response in that it is fabricated from a material selected to exhibit inherently as a direct material property a direct variable electrical and for example photoelectric response to different parts of the source spectrum.

16. An apparatus in accordance with claim 15 wherein the detector comprises a material or materials selected from cadmium telluride, cadmium zinc telluride (CZT), cadmium manganese telluride (CMT), germanium, lanthanum bromide, thorium bromide.

17. An apparatus in accordance with claim 1 wherein the means to cause an object to move relative to and through the scanning zone comprises an object conveyance means in the form of a planar conveyor to convey an object through a scanning zone defined by a static source and detector array.

18. An apparatus in accordance with claim 1 comprising an X-ray source and at least two and no more than five linear radiation detectors spaced therefrom.

19. An apparatus in accordance with claim 18 comprising a tungsten X-ray source.

28. A method in accordance with claim 20 further comprising the steps of:

in a first mode of operation, generating a plurality of images from a laterally spaced series of linear arrays of detectors in the manner of any preceding claim; and

further in a second mode of operation, generating a single collimated primary curtain beam, directed at a particular linear detector within the series of detectors,

using the other detectors to detect diffracted secondary beams,

processing this information from the other detectors to give additional information concerning scattered radiation.

29. A method in accordance with claim 28 wherein both modes of operation are applied sequentially or closely successively or effectively simultaneously.

20. A method of obtaining an image of an object comprising the steps of:

providing a radiation source and a series of at least two and no more than five linear radiation detectors spaced therefrom to define a scanning zone therebetween;

causing an object to move relative to and through the scanning zone;

generating a direct image from the output of at least one linear detector;

generating at least one intermediate image from at least one adjacent pair of linear detectors, by processing the output of said pair of detectors and generating an image representative of an output intermediate between the two said detector outputs;

such that at least five images are generated in total;

displaying such images successively and thus displaying the monocular movement parallax between the images.

21. A method in accordance with claim 20 wherein the images are displayed successively as individual two-dimensional images.

22. A method in accordance with claim 20 wherein a laterally spaced series of at least three but no more than five linear detectors is provided to generate a series of at least six images for successive display.

23. A method in accordance with claim 20 wherein the method comprises generating at least two intermediate images from at least one adjacent pair, and where applicable generating at least one intermediate image from a plurality and for example each adjacent pair, of linear detectors, by processing the output of the or each said pair of detectors and generating an image representative of an output intermediate between the two said detected outputs.

24. A method in accordance with claim 20 wherein the successive images are displayed at custom definable refresh rates and directions under observer control to facilitate interpretation.

25. A method in accordance with claim 20 wherein images generated by at least some of the linear detectors are resolved into two energy bands.

26. A method in accordance with claim 20 wherein images generated by at least some of the linear detectors are resolved spectroscopically across at least a substantial part of the source spectrum, and spectroscopic resolution of transmitted radiation obtained from the output of each such linear detector is represented in the displayed image.

27. A method in accordance with claim 26 wherein a banded mapping is used to represent spectroscopic resolution in the generated image in that the source spectrum is divided into a plurality of bands and different colours are used to represent each such band in the displayed image.

30. A method of in accordance with claim 20 comprising providing an X-ray radiation source and a series of at least two and no more than five linear X-ray detectors.