Question

Differentiate between fringes of equal inclination and fringes of equal thickness

Answer 1

layer on which the light rays are incident at the same angle φ—hence the term “fringes of equal inclination.” Such fringes are often included among the effects of the optics of thin films, although they also arise in plates of comparatively large thickness.

Answer 2

FRINGES  OF EQUAL INCLINATION

•      when a transparent layer of constant thickness is illuminated with a diverging or converging beam of monochromatic light or with a nonparallel beam of rays of a more complex structure, a pattern of alternating light and dark bands observed
• These fringes are seen when light from an extended source falls on a thin film made of an optically denser medium.
• Fringes of equal inclination is also called Haidinger fringes.

FRINGES OF EQUAL THICKNESS:

•  It is observed when light is reflected from a plano-convex lens of a long focal length placed in contact with a plane glass plate.
• Fringes of equal thickness is also called Newton rings.