Question

How fringes are formed?

Answer 1

1. Fringes, which are created by the diffraction or interference of radiation with a quantifiable wavelength, are regions of contrastive brightness or blackness.
2. Depending on whether two light beams are in phase or out of phase, interference fringes can be brilliant or dark.
3. Different-shaped interference fringes When two mirrors are parallel to one another, as they are when the observation point is on a line perpendicular to the line connecting the two sources of light:

3.1. Produces circular fringes, and

3.2. Produces straight or conic fringes when the mirrors are tilted at an angle.

As a result of the interference phenomena, a screen positioned on the opposite side records a pattern of alternating bright and dark bands known as fringes.