Physics Diffraction

Question

The Hubble Space Telescope has a diameter of 2.4 m.

What is the angular limit of resolution due to diffraction when a wavelength of 790 nm is viewed? 

Answer 1

Hi, there! For this problem we have to apply what is known as the Rayleigh criterion. It states

The diffraction limit to resolution states that two images are just resolvable when the center of the diffraction pattern of one is directly over the first minimum of the diffraction pattern of the other

The first minimum happens at the angle

θ = 1.22 λ/D

You are given a monorchromatic light of wavelenght λ = 790 nm and the diameter D = 1.24 m of the aperture of the telescope, so plug those and you are ready to go!