All Problems

Diffraction of Light

Problem 5.149

There is a microscope whose objective's numerical aperture is \(\sin \alpha=0.24,\) where \(\alpha\) is the half-angle subtended by the objec tive's rim. Find the minimum separation resolved by this microscope when an object is illuminated by light with wavelength \(\lambda=0.55 \mu \mathrm{m}\).

Reveal Answer
dmin=0.61λ/sinα=1.4μmd_{\min }=0.61 \lambda / \sin \alpha=1.4 \mu \mathrm{m}