| Collimator |
Shopping Collimator |
Information AboutCollimator |
| CATEGORIES ABOUT COLLIMATOR | |
| neutron instrumentation | |
| synchrotron instrumentation | |
| x-ray instrumentation | |
| radiology | |
| particle accelerators | |
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Collimators are used in X- and gamma-ray imaging because it is not yet possible to focus such short wavelengths into an image with lenses as at optical or near-optical wavelengths. In the bottom of the illustration to the left, a collimator has been added. This is a sheet of lead or other material opaque to the incoming radiation with many tiny holes bored through it. Only rays travelling nearly parallel to the holes will pass through them - any others will be absorbed by hitting the plate surface or the side of a hole. This ensures that rays are recorded in their proper place on the plate, producing a clear image. Although collimators improve the resolution, they also reduce the Intensity of the signal--most lead collimators let less than 1% of incident Photon s through. For this reason, attempts have been made to replace collimators with electronic analysis. Collimators are also used with radiation detectors in Nuclear Power Station s for monitoring sources of Radioactivity . In optics, a Collimating Lens is one that produces parallel rays of light. Collimators may be used with Laser Diode s. Proper collimation of a laser source with long enough Coherence Length can be verified with a Shearing Interferometer . |
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