optical image n.
An image formed by the refraction or reflection of light.
There is neither error nor truth in the optical image: It just exists physically.
A topsy-turvy world; it is even upside down as an optical image.
It is situated, as will be seen at what would be, if the tinfoil were a mirror, the optical image of the ball in the mirror.
And the optical image is a mere vibrating blur to a child—and, indeed, to a passionate adult.
Purely physical considerations account for the refraction of the light which produces an optical image of a bent stick.