Enter the wavelength (um) and the numerical aperture into the Calculator. The calculator will evaluate the Resolving Power. 

Resolving Power Formula

e = .61 * L/NA


  • e is the Resolving Power (um)
  • L is the wavelength (um)
  • NA is the numerical aperture

To calculate Resolving Power, divide the wavelength by the numerical aperture, then multiply by .61.

How to Calculate Resolving Power?

The following steps outline how to calculate the Resolving Power.

  1. First, determine the wavelength (um). 
  2. Next, determine the numerical aperture. 
  3. Next, gather the formula from above = e = .61 * L/NA.
  4. Finally, calculate the Resolving Power.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

wavelength (um) = 0.55

numerical aperture = 0.9