A periscope is an

2. A periscope is an OPTICAL DEVICE • that is used for being able to see around and over objects. • Periscopes are generally made two different ways. • With mirrors • With prisms To the right are diagrams of the two most commonly used periscopes. MIRROR PRISM

3. This is my drawing of a periscope 

4. Periscopes that use mirrors are very simple and were explained on the previous slide. • Periscopes using prisms instead of mirrors are more complex, but more efficient. • When prisms are used, there must be a lens or multiple lenses to magnify or adjust the image • The light goes through one side of the prism, reflects off the hypotenuse, and out through the third side.

5. You might be asking, why does the light just reflect off the hypotenuse and not refract?

6. Periscopes are used in many submarines to see above water from a shallow depth. • Periscope’s main uses are for military and naval purposes. • The military use of periscopes started in World War I when armies used them on rifles to see over top of trenches. • Periscopes have also been used in tanks since world war two, allowing the drivers to see ahead of the tank without leaving the safety of the tank.

7. Johann Gutenberg invented the periscope in the 1430s to help people see over the crowd at the vigintennial religious festival. • Optical designer Sir Howard Grubb is credited with the perfection of the periscope in World war 1. • Mechanical engineer Simon Lake is credited with the naval invention of the periscope in 1902.

8. Photonics masts have been used by the US navy since 2004. • Similar to a periscope, but does not need a periscope tube, and lowers the risk of water leakage. • They are electronic/digital. • Displays an image on a screen in the control center of the submarine similar to that of a digital camera. • The photonics mast has every advantage over a normal periscope. • Allows for a larger line of sight and less constraints. • Less danger • Looks cooler

9. Even cats use periscopes!