Airy Disk and Sensor Sampling Calculator
Compare ideal circular-aperture diffraction diameter, pixel pitch and incoherent optical cutoff.
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Result
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Calculation steps
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How to calculate
Use the first-dark-ring Airy diameter approximation for an ideal circular pupil, then compare physical diameter and frequency limits with sensor sampling.
Airy diameter≈2.44λN; incoherent cutoff=1/(λN); sensor Nyquist=1/(2×pixel pitch)
Worked example
At wavelength 550 nm and working f/8, the Airy diameter is 10.736 µm. At 4 µm pixel pitch this is 2.684 pixel pitches.
Assumptions and input details
Ideal unobstructed circular pupil, monochromatic light, image space in air and paraxial working f-number. The factor 2.44 is rounded. Optical cutoff refers to incoherent imaging; coherent imaging differs. No aberration, demosaicing, sharpening, aliasing or perceptual resolution model. Enter working aperture for finite-conjugate macro imaging.
References: Edmund Optics: Airy disk diameter and limits
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NIST measurement tables · Japanese traditional units · Mainland China and Hong Kong unit distinctions
Using this calculator
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