Optics
Rayleigh Criterion
The minimum angular separation at which two point sources can be resolved by a circular aperture.
Variables
θminrad
Minimum resolvable angle
λm
Wavelength
Allowed values: greater than 0
Dm
Aperture diameter
Allowed values: greater than 0
Your notes
0/5000
Check value
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- λ = 2 m (Wavelength)
- D = 3 m (Aperture diameter)
Result: θmin = 0.81333333 rad
Other optics formulas with the same quantities
- Double-Slit Interference (Wave Optics) shares Wavelength
- Fringe Spacing (Wave Optics) shares Wavelength
- Diffraction Grating (Wave Optics) shares Wavelength
- Resolving Power of Grating (Wave Optics) shares Wavelength
- F-Number (f-stop) (Optical Instruments) shares Aperture diameter
- Constructive Interference Condition (Wave Optics) shares Wavelength
Where this formula is listed
- Optics formulas, under Resolution.
- In the optics list it comes after Malus's Law and before Magnifying Glass Magnification.
- Optics formula sheet, one of 34 formulas printed with symbol keys and SI units.
- The full formula index, grouped by category and topic.
Common questions
What is the Rayleigh Criterion formula?
Rayleigh Criterion is written θ_min = 1.22(λ/D). The minimum angular separation at which two point sources can be resolved by a circular aperture. It belongs to Optics, under Resolution.
What are the units in θ_min = 1.22(λ/D)?
In SI units, θ_min is minimum resolvable angle, measured in rad; λ is wavelength, measured in m; D is aperture diameter, measured in m.