Ray 3 starts at the top of the object, passes through the focal point on the near side of the lens, is refracted by the lens, and continues parallel
to the axis on the far side of the lens.
The image created by the lens is shown in the diagram below, where all three rays are combined together. The point at which the rays
converge indicates the location of the top of the image. The image is inverted, smaller than the object and real.
This example provides a model for a typical camera lens, which creates an inverted real image on the film or digital recording device on the far
side of the lens.
Ray 3:
Passes through near focal point, then
parallel to axisImage
Inverted, smaller, real
33.3 - Diverging lens: ray-tracing diagram
Like a convex mirror, a single diverging lens produces only one kind of image. The image is always upright, smaller than the object, and virtual.
We use three rays to analyze the image.
Ray 1 starts parallel to the principal axis. With a diverging lens, it refracts away from the principal axis. To have the ray pass through a focal
point, we must extend it backward using a virtual ray as shown in the diagram.
Rays for a diverging lens
What type of image will be produced?
Ray 1
Parallel to axis, virtual ray passes
through near focal point