What is understood by lateral displacement of light? Illustrate it with the help of a diagram. List any two factors on which the lateral displacement in a particular substance depends.

Lateral Displacement

When a ray of light passes obliquely through a rectangular glass slab, it undergoes refraction at two parallel surfaces (air-glass interface and glass-air interface). The emergent ray is parallel to the direction of the incident ray but is shifted sideways.

The perpendicular distance between the original path of the incident ray (produced forward) and the emergent ray coming out of the glass slab is called lateral displacement.

Diagram

Factors on which Lateral Displacement Depends (Any Two):

1. Thickness of the medium (glass slab): Lateral displacement is directly proportional to the thickness of the glass slab. A thicker slab produces greater displacement.
2. Refractive index of the medium: It is directly proportional to the refractive index of the glass slab. A medium with a higher refractive index bends light more, increasing the displacement.
3. Angle of incidence: Lateral displacement increases with an increase in the angle of incidence ($i$).