Point the lens at a distance object outside the window – for instance a tree or building. The greater the distance, the better. Rays of light from this object are taken to be parallel as the ...

Lenses can either be convex/ converging or concave/ diverging. Convex lenses take parallel light rays from distant objects and bend them to converge at a single point known as the focal point.

Cameras and eyes contain convex lenses. For a distant object that is placed more than twice the focal length from the lens, the image is: between F and 2F on the opposite side of the lens to the ...