collimator

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collimator

[kol´ĭ-ma″ter]

a diaphragm or system of diaphragms made of an absorbing material, designed to define and restrict the dimensions and direction of a beam of radiation.

col·li·ma·tor

(kol'i-mā'ter),

A device of high absorption coefficient material used in collimation.

collimator

[kol′imā′tər]

Etymology: L, collinare, to bring into alignment

a device for limiting the size and shape of a radiation beam. It is used to reduce scatter radiation, thereby decreasing the patient dose needed and increasing radiographic quality.

col·li·ma·tor

(kol'i-mā-tŏr)

A device with blocks or jaws that restrict a beam of emitted radiation to a given area; composed of a high-absorption coefficient material such as lead or tungsten.

collimator

1. A shield, shutter or cone, usually of lead, attached to an X-ray tube to limit the width of the beam.

2. A thick perforated lead plate designed to allow passage only of parallel radiation, as in a GAMMA CAMERA.

collimator

An optical apparatus for producing parallel rays of light. It usually consists of a positive achromatic lens, with an illuminated object (a slit, a graticule, a scale, etc.) placed at one of its focal points, so that light from any point on the object emerges from the collimator parallel.

col·li·ma·tor

(kol'i-mā-tŏr)

A device of high absorption coefficient material used in collimation.

collimator

a device, sometimes a diaphragm, or series of diaphragms, which control the direction and the dimensions of the x-ray beam.

References in periodicals archive ?

A laser collimator doesn't need crosshairs, so you just need to drill the holes for your laser mounting screws.

Contemplating collimators: make high-precision tools from plastic piping and underwear

All exposures with both universal and enhanced collimator devices were made using an intraoral Planmeca Prostyle x-ray unit (Intra, Planmeca USA, Roselle, Ill).

Technical performance of universal and enhanced intraoral imaging rectangular collimators

239]Pu preparation was measured using low-voltage semiconductor detectors with collimators [10].

Synchronous changes of the shape of histograms constructed from the results of measurements of [sup.90]Sr [beta]-Decay and [sup.239]Pu [alpha]-decay observed in more than 3000 km distant laboratories

Other parameters, including number of projections, time per projection, and number and distribution of pinholes on the collimator, were maintained constant for each target organ.

Performance assessment of the single photon emission microscope: high spatial resolution SPECT imaging of small animal organs

While the gantry is moving into position, each collimator leaf is positioned according to the treatment plan.

Motors take on cancer

After adding the metal rod to the film holder, the assistant adds the collimator ring to the metal rod, using both the rod and the film holder as fixed references for properly orienting the collimator ring.

Assembly and clinical use of the XCP dental x-ray film holder orientation devices in dentistry

The neutron flux density after the collimator will be one order of magnitude less ([[PHI].

Project of neutron beta-decay A-asymmetry measurement with relative accuracy of (1-2) X [10.sup.-3]

De Neve W, De Gersem W, Derycke S, et al, Clinical delivery of intensity modulated conformal radiotherapy for relapsed or second-primary head and neck cancer using a multileaf collimator with dynamic control.

Recent advances in radiotherapy for head and neck cancers

The first patent - number 6,246,812 B1 - covers Alliance's V-groove dual fibre collimator technology, which incorporates a proprietary tunable collimator element in the assembly of DWDM filter components to enhance DWDM thin film filter manufacturing.

Alliance Fiber Optic Products receives US patents for optical technologies

The system is available in two models: the XUL with a fixed collimator and the XULM with micro-focus tube and four motor-set collimators.

Thickness measurement

FDA 510(k) clearance was granted to Varian's Millennium MLC-120 multileaf collimator (MLC), a device used with its medical linear accelerators for increasing the cancer-killing energy directed at tumors, while minimizing the radiation dose to surrounding healthy tissue.