What is the optical axis?

1 Answer
A08
Feb 26, 2017

Optical axis of a lens is an imaginary straight line which passes through the geometrical center of a lens joining the two centers of curvature of surfaces of lens. It is also called principal axis of the lens.

met.reading.ac.uk

As shown in the figure above, #R_1 and R_2# are centers of curvature of of two surfaces. Straight line joining these two is the optical axis.

A ray of light traveling along this axis is perpendicular to the surfaces and, therefore, its path remains un-deviated.

The optical axis of a curved mirror is the line passing through its geometric center and center of curvature.

Related questions
See all questions in Thin Lenses
Impact of this question
10983 views around the world
You can reuse this answer
Creative Commons License