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following factors: The nature of the medium. The colour or wavelength of the
incident light.

Refraction of Light through a Glass Slab

When a ray light is passing from air to glass, that is, from a rarer medium to a
denser medium, the refracted ray bends towards the normal drawn at the point of
incidence. In this case angle of i > angle of r. But when the ray of light is passing
from glass to air, that is, from a denser medium to a rarer medium the refracted ray
bends away from the normal. In this case angle of r > angle of i. The emergent ray,
O1E which is nothing but the refracted ray emerging out of the glass slab is
parallel to the incident ray. This means that the refracted ray (emergent ray) has
been displaced from its original path by a distance XY. This displacement is
referred to as lateral displacement.

Lenses

A lens is a portion of a transparent refracting medium bounded by two generally
spherical or cylindrical surfaces, or one curved and one plane surface. Convex
lenses and converging lenses are the two types of lenses.

Convex Lens

A convex lens is one that is thicker in the center and thinner at the edges. A convex
lens has at least one surface that bulges out in the middle. Convex lenses are
classified as bi-convex or double-convex, Plano - convex lens and concavo -
convex lens based on their shape.

Concave Lens

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