Periscope and Reflection of Light

A periscope is a device that allows an observer to see objects that are not in their direct line of sight by using reflection of light. It consists of two mirrors or prisms arranged at an angle to each other, which reflects light and redirects it towards the observer's eye. The phenomenon of reflection of light is the basis on which a simple periscope works.

Reflection of Light

Reflection is the change in direction of a wavefront at an interface between two different media so that the wavefront returns into the medium from which it originated. When light strikes a surface, it can be reflected, absorbed, or transmitted. In the case of a periscope, reflection occurs when light rays strike the mirrors or prisms.

Working of a Periscope

1. Light enters the periscope through an aperture or a small opening.
2. The first mirror or prism situated at the lower end of the periscope reflects the light rays at an angle of 45 degrees.
3. The light rays then strike the second mirror or prism located at the upper end of the periscope.
4. The second mirror reflects the light rays again, redirecting them towards the observer's eye.
5. As a result, the observer can see the object or scene that is located above the periscope, even though it is not in their direct line of sight.

Advantages of Reflection in a Periscope

1. Reflection allows the light rays to change direction without changing their speed or medium.
2. It enables the periscope to provide an upright image to the observer, unlike the inverted image formed by refraction in lenses.

Conclusion

In conclusion, a simple periscope works based on the principle of reflection of light. It utilizes mirrors or prisms to reflect and redirect light rays towards the observer's eye, allowing them to see objects or scenes that are not in their direct line of sight. The phenomenon of reflection of light plays a crucial role in the functioning of periscopes and enables them to provide an upright image to the observer.