Diffraction Resolution
Calculate diffraction-limited angular resolution and ground spot size for circular apertures.
Angular resolution
1.38 arcsec
6.71 microrad Rayleigh angle
Resolvable separation
3.36 m
at 500.0 km target range
Airy disk diameter
6.71 m
first dark ring across the target plane
Calculation breakdown
Rayleigh diffraction limit
Aperture diameter narrows the diffraction cone; wavelength and range turn that angle into target-plane separation.
theta = 6.71 microrad
Wavelength
550 nm
longer wavelengths broaden the cone
Aperture
100 mm
D / lambda = 181,818
Linear resolution
3.36 m
Rayleigh separation at 500 km
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