Final answer:
The equation expressing the Rayleigh criterion, which describes the resolution limit for two just-resolvable images in terms of their diffraction patterns, is 0 = 1.22 λ/D. None of the listed options a) θ=2λ/D, b) θ=λ/D, c) θ=3λ/2D, or d) θ=λ/2D, correctly reflect this principle.
Step-by-step explanation:
The principle related to resolution that states, "Two images are just resolved when the center of the diffraction pattern of one is directly over the first minimum of the diffraction pattern of the other" is known as the Rayleigh criterion. The equation that expresses this principle is the following:
0 = 1.22 λ/D
Where θ is the angle of separation, λ is the wavelength of light, and D is the diameter of the aperture. Given the information and the provided options, the correct answer is not listed among them, as the correct equation is represented by 0 = 1.22 λ/D.