Use the slider to increase or decrease the distance between the two prisms. Click on the 'Start' button to start an animation of the path of light rays in the periscope.
| Periscopes consist of two 90°/45°/45° prisms arranged as
shown. Because the critical angle for a glass/air boundary is approximately 42°, light is
totally internally refracted when it strikes the longest side (the hypotenuse) of the
prism, because the angle of incidence is 45°.
Use the slider to increase or decrease the distance between the two prisms. Click on the 'Start' button to start an animation of the path of light rays in the periscope. |