Periscopes and Prisms

There have two method to make periscope. First by using mirror, second by using prisms. Which method is batter? Why?
- Anonymous
SMK Air Itam, Malaysia

It depends on what you want for the properties of the periscope. Mirrors almost certainly will weigh less than the chunks of glass needed for the prism solution. Prisms might be more durable and give sharper images (for example, they won’t warp when they heat up and cool down, and they probably won’t get dented when dropped, but perhaps could break). Mirrors also may oxidize over time, while a prism will last practically forever without changing.

Tom

(published on 10/22/2007)