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Diffraction-Limited MTF Calculator

Calculate and plot the diffraction-limited Modulation Transfer Function for optical systems.  Greivenkamp, Field Guide to Geometrical Optics, p. 88

Formulas
Diffraction-Limited MTF: $$\text{MTF}(\xi) = \frac{2}{\pi} \left[ \arccos(\xi) - \xi \sqrt{1 - \xi^2} \right], \quad \xi = \frac{f}{f_\text{cutoff}}$$
Cutoff frequency: $f_\text{cutoff} = \dfrac{1}{\lambda \cdot f/\#_W}$  (lp/mm)    Working F/#: $f/\#_W = (1-m)\,f/\#\,$ (Greivenkamp p. 29)
Frequency conversion: $\text{lp/mm} = \dfrac{\text{cyc/deg}}{\text{EFL} \times \pi/180}$   F/#: $f/\# = \text{EFL}/D$
nm
mm
mm
(0 = ∞ obj)

MTF at specific frequency

cyc/deg
— → MTF = —