Physics A-Level
Aperture stop
What Aperture stop means in Physics A-Level, as defined for AQA.
Definition of Aperture stop
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Reference: AQA
Reduces spherical aberration, which arises when a spherical mirror brings marginal rays to a different focus from paraxial rays.
Topics that use Aperture stop
- Reflecting telescopes (A-level only) (AQA A-Level)
Related terms
- Chromatic aberration
- Convex secondary mirror
- Folded optical path
- Formation of a real intermediate image
- Optical ray construction and labelling
- Parabolic mirror
- Reflection at curved and plane surfaces
- Central obstruction
Using Aperture stop in the exam
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