Optics Calculators

Interactive first-order optical calculators — F/#, NA, MTF, thin lens, Airy disk, depth of field, and more. Formulas from Greivenkamp, Field Guide to Geometrical Optics (SPIE, 2004).

Calculators

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Optics Conversions

Convert between cone acceptance angle, NA, and F/#. Plot how NA and F/# roll off with field angle (cos φ law). Compute solid angle (steradians) from half-cone angle.

3 tools

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Diffraction-Limited MTF

Plot the OTF/MTF for a diffraction-limited system. Query MTF at any spatial frequency in lp/mm or cyc/deg. Includes working F/# for finite conjugates.

Live plot

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Thin Lens

Solve for image distance, object distance, or focal length. Computes magnification, working F/#, image-space NA, and object-to-image distance L.

3 solve modes

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Airy Disk

Airy disk diameter, ring radii, and encircled energy fractions as a function of wavelength and working F/#. Interactive PSF cross-section plot.

Plot + table

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Depth of Focus & Field

Geometrical depth of focus (image side) and depth of field (object side). Near/far limits, hyperfocal distance. Plots DOF vs focus distance.

Live plot

Reference

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Greivenkamp (2004)

All formulas sourced from Field Guide to Geometrical Optics, SPIE Field Guides Vol. FG01.

Source