Rayleigh criterion
What Rayleigh criterion means in Physics A-Level, as defined for AQA.
Definitions of Rayleigh criterion
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Reference: AQA
Gives the minimum angular resolution θ of a telescope as θ ≈ λ ÷ D, where λ is the wavelength and D is the diameter of the objective aperture.
Two stars are just resolved when the centre of one diffraction pattern falls on the first dark ring of the other.
Topics that use Rayleigh criterion
- Advantages of large diameter telescopes (A-level only) (AQA A-Level)
Related terms
- Astronomical calculations
- Collecting power
- Quantum efficiency
- Radian
- Resolution
- Airy pattern
- Angular measure
- Angular resolution
Using Rayleigh criterion in the exam
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