gen-state-diffraction-at-small-apertures-precisely-and-explain-w-33de

State diffraction at small apertures precisely and explain why it matters in 2-3 sentences.

## Diffraction at Small Apertures **Precise Statement**: When light passes through an aperture comparable to or smaller than its wavelength, it spreads out significantly rather than traveling in straight lines, with the angular width of the central diffraction maximum given by θ ≈ λ/D (where λ is wavelength and D is aperture diameter). **Why It Matters**: This effect fundamentally limits the resolving power of optical instruments like telescopes and microscopes—you cannot simply make things arbitrarily sharp by focusing harder. It also explains why we can hear around corners but not see around them (sound wavelengths ~cm vs light wavelengths ~μm), and sets the ultimate physical limit on how small we can focus light for applications from microscopy to photolithography.