Abstract: An X-ray inspection system in which a thin X-ray absorber is placed upstream of an object under investigation so as to remove low energy X-rays, typically below 0.5 MeV. The absorber may be a sheet of lead 10 mm thick. Where the X-ray inspection system which incorporates a detector which relies on the electromagnetic cascade effect produced in suitable materials when bombarded with X-rays so that energy is transferred into the material at different depths depending on the energy of incident X-rays, and the first component on which the X-rays impinge comprises a relatively thin crystal this unwanted background may be reduced by placing a vessel containing a fluid whose density is less than that of air, in front of the detector crystal array. Typically the fluid is helium at atmospheric or slightly greater than atmospheric pressure. The background can be reduced by applying a magnetic field in the region in front of the detector crystal array so as to sweep away electrons from that region.

Abstract: A fibre optic epi-fluorescence imaging system in which the optical fibres are rearranged so that the system can be used for measuring luminescence samples. The system comprises at least two optical fibres (32, 46) or bundles of fibres which lead to a CCD camera (74), the fibres or bundles of fibres from all samples being arranged in two sets, a first set which are formed from a non-fluorescing material and a second set which are formed from a material which may fluoresce but enables the fibres formed therefrom to have a higher numerical aperature than those of the first set.

Abstract: An X-ray scanning system for high speed imaging of an object using an X-ray source for generating a fan shaped X-ray beam (12) for traversing a linear section or slice of the object, and a linear array of detectors (14) on the opposite side of the object (10) from the source which generate light depending on the X-ray image incident thereon, wherein optical fibers (16) link the detectors to the input of an image intensified CCD camera (18), the fiber ends forming a planar array having an aspect ratio which is different from that of the linear array of detectors and which matches the aspect ratio of the camera, the detector array having an addressable array of N.times.

Abstract: Apparatus wherein an image intensifier (16) is interposed between a plurality of emission sites (10) from which emanate photons and a photo-detector (20) coupled to the output of the image intensifier to produce separate electrical signals processed by computer (24) to enable the respective signals to be correlated to the sites of the original emission source.