how to compare and contrast the interference pattern with coherently illuminated single slit

In the interference pattern, all the bright fringes are of the same intensity. In diffraction pattern, all the fringes are not of the same intensity. The central fringe is the brightest and the intensity keeps decreasing for successive fringes.

In interference, the intensity of the minimum is generally zero or very small, and there is a good contrast between bright and dark fringes. In diffraction, the intensity of minima is never zero and there is poor contrast between bright and dark fringes.

The width of interference fringes may or may not be equal. But the width of diffraction fringes is always unequal.

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