There are mainly two types of focus placement in monocular design: one where the focus wheel is attached to the top of the body and the other where a collar is built into the body.

A simple way to fracture white light into a rainbow is by creating a prism with a glass of water. From Sciencing, here's how. What you'll need: • A drinking glass • Flashlight • ...

Porro-prism binoculars have zigzagged barrels, while those with roof prisms have sleek, straight barrels. Features Recently, I toured the universe using Celestron’s Nature DX ED 10×50 Binoculars.

In other words, a prism seems only to bend (refract) light, leaving it otherwise unaltered. But it does so to different degrees (that is, at different angles) for different colors.