periskoopi

Periskoopi is a Finnish word that translates to "periscope" in English. A periscope is an optical instrument that allows observation of an area that is not within the direct line of sight. It typically consists of a tube with mirrors or prisms at each end, arranged parallel to each other at a 45-degree angle. Light from the object being observed enters the top of the periscope, reflects off the top mirror or prism, travels down the tube, reflects off the bottom mirror or prism, and then reaches the observer's eye.

The primary function of a periscope is to enable viewing over, around, or through an obstacle. This makes them invaluable in various applications. The most well-known use is in submarines, where they are crucial for surfacing and observing the surrounding environment without fully exposing the vessel. They are also employed in tanks and armored vehicles for the crew to see outside their protected compartments. Additionally, periscopes can be found in observation posts, trenches, and even in some civilian applications like surveying or for children's toys to see over fences. The design of a periscope can vary, from simple handheld devices to complex, integrated systems with magnification and remote control capabilities.