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Gamma correction in computers is used, for example, to display a gamma = 1.8 Apple picture correctly on a gamma = 2.2 PC monitor by changing the image gamma. Another usage is equalizing of the individual color-channel gammas to correct for monitor discrepancies.
Scintigraphy (from Latin scintilla, "spark"), also known as a gamma scan, is a diagnostic test in nuclear medicine, where radioisotopes attached to drugs that travel to a specific organ or tissue (radiopharmaceuticals) are taken internally and the emitted gamma radiation is captured by gamma cameras, which are external detectors that form two-dimensional images [1] in a process similar to the ...
Single-photon emission computed tomography (SPECT, or less commonly, SPET) is a nuclear medicine tomographic imaging technique using gamma rays. [1] It is very similar to conventional nuclear medicine planar imaging using a gamma camera (that is, scintigraphy ), [ 2 ] but is able to provide true 3D information.
For example, a volume may be viewed by extracting isosurfaces (surfaces of equal values) from the volume and rendering them as polygonal meshes or by rendering the volume directly as a block of data. The marching cubes algorithm is a common technique for extracting an isosurface from volume data. Direct volume rendering is a computationally ...
Schematic of a basic rectilinear scanning system. Cassen's original rectilinear scanner used calcium tungstate (CaWo 4) crystal as the radiation detector. Later systems used a Sodium iodide (NaI) scintillator, as in a gamma camera. [7] The detector must be connected by mechanical or electronic means to an output system.
A gamma camera (γ-camera), also called a scintillation camera or Anger camera, is a device used to image gamma radiation emitting radioisotopes, a technique known as scintigraphy. The applications of scintigraphy include early drug development and nuclear medical imaging to view and analyse images of the human body or the distribution of ...
For example, sodium in glass is of great importance but can be hard to measure non destructively: X-ray fluorescence (XRF) and particle-induced X-ray emission (PIXE) are both sensitive only to the surface few microns of the sample because of the low energy (and consequent high absorption coefficient) of the Na K X-rays (1.05 keV).
Some backscatter X-ray scanners can scan much larger objects, such as trucks and containers. This scan is much faster than a physical search and could potentially allow a larger percentage of shipping to be checked for smuggled items, weapons, drugs, or people. There are also gamma-ray-based systems coming to market. [10]