Abbe Theory

Abbe's Theory explains how the resolution of an optical system, like a microscope, is limited by the wavelength of light and the system's ability to collect light waves. It states that two objects are just distinguishable when their images are separated by a distance equal to half the wavelength divided by the numerical aperture (a measure of how much light the lens gathers). Essentially, it defines the smallest detail that can be observed, showing that increasing light collection or using shorter wavelengths improves resolution, allowing more detailed images at microscopic levels.