An imaging system's ability can be limited by either aberration or diffraction.
Which one dominates, is interpreted as the Point Spread Function.
If the PSF is dominated by diffraction (the narrower the aperture of the lens), the angular resolution can be determined by the Rayleigh criterion.
two point sources are regarded as just resolved when the principal diffraction maximum of one image coincides with the first minimum of the other.1 If the distance is greater, the two points are well resolved and if it is smaller, they are regarded as not resolved. Rayleigh defended this criteria on sources of equal strength.
The answer to your question is that the Rayleigh criterion can be used with coherent and incoherent light sources too.
In a coherent imaging system, the amplitudes of signals from different parts of the image add, and the result is then squared to form the intensity image, while in an incoherent system the intensities add directly. Consequently, the use of the simple definition of resolution based on the half-power width is not always adequate. It is, therefore, common to employ the Rayleigh criterion, which states that two closely space illuminated points are distinguishable from each other if the maximum response to point A is located at the zero of the response to the point B.
You can see the image intensity for two mutually coherent point sources, and for two incoherent point sources.