ABSTRACT
The spatial resolution is defined by the radius of the Airy disk. Depending on the exact resolution criterion, factors slightly different than 0.61 may be used in Equation 12.1, but these variations do not alter the result significantly. From Equation 12.1, an objective lens with NA = 0.3 and a light wavelength λ = 532 nm provides a resolution of ∼1 µm. Hence, optical microscopy measurements are generally useful for observing feature sizes that are a micron or larger. Two methods that offer improved resolution are electron microscopy (Sections 12.3 through 12.6) and scanning probe microscopy (Section 12.7).
