Question 28
Lenses and Optical InstrumentsIn a ray diagram for a thin converging lens, a ray that is not parallel to the optic axis but passes through the optic centre will
- A.pass through undeviated
- B.pass through the centre of curvature after refraction
- C.emerge parallel to the principal axis
- D.pass through the principal focus after refraction.
Show the answer and explanation
Answer: A (pass through undeviated)
Explanation
Near its centre a thin lens is like a thin parallel-sided slab, so a ray through the optical centre goes straight on.