Physics A-Level
Collimator
What Collimator means in Physics A-Level, as defined for AQA, OCR.
Definitions of Collimator
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Reference: AQA
A thick lead block pierced by many narrow parallel channels that absorbs oblique gamma photons so only near-parallel photons reach the crystal.
A lead block with parallel holes that admits only near-parallel gamma rays, so each point on the detector maps to a known direction.
Topics that use Collimator
- Gamma camera (A-level only) (AQA A-Level)
- Diagnostic methods in medicine (OCR A-Level)
Related terms
- Annihilation
- Clinical diagnosis from count maps
- Coincidence detection
- Computer
- Dynodes
- Fluorine–18
- Functional medical imaging
- Medical tracer
Using Collimator in the exam
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