Question

The limit of resolution of an instrument is

• A. Directly related to its resolving power.
• B. Inversely related to its resolving power.
• C. Not related to its resolving power.
• D. Same as its resolving power.

Answer 1

The correct option is B Inversely related to its resolving power.

The resolution of a microscope is defined as the smallest distance between two points on a specimen that can still be distinguished as two separate entities. Numerical aperture determines the resolving power of an objective but the total resolution of a microscope system is also dependent on the numerical aperture of the substage condenser. Shorter wavelengths are capable of resolving details to a greater extent than the longer wavelengths. There are several equations that have been derived to express the relationship between numerical aperture, wavelength and resolution:
R = Wavelength / (2NA)
R = 0.61 x wavelength / NA
Where, R is the resolution, NA is the numerical aperture
So, we can see, the wavelength is directly proportional to the resolution but indirectly to the resolving power.