Portrayed is a ray from an object which heads toward and then into a lens. Suppose if the ray is a principal ray where does it go from there?

Ans:

This is the simple principal ray. It is the merely principal ray that is the same for both a converging lens and a diverging lens. It is the principal ray which leaves the object and heads straight toward the centre of the lens that is straight toward the point at which the plane of the lens and the principal axis of the lens intersect. That principal ray stays on going straight through the lens.