NCERT · Class 10 · Science · Light – Reflection and RefractionDefine lateral displacement of a light ray passing through a glass slab.

Lateral displacement of a light ray passing through a rectangular glass slab is defined as the perpendicular distance measured between the original path of the incident light ray and the emergent light ray coming out of the opposite parallel face of the glass slab. This lateral shift occurs because the extent of bending at the first air-glass interface is exactly equal and opposite to the bending at the second glass-air interface, resulting in parallel displacement of the emergent ray without altering its final directional angle.