10 Examples of Total Internal Reflection
Total internal reflection is a phenomenon that occurs when light rays traveling from a denser medium to a less dense medium are reflected back into the denser medium. This happens when the angle of incidence of the light rays is greater than the critical angle.
Examples of total internal reflection include colorful rainbows, glittering diamonds, and moonlight on the lake.
Examples of Total Internal Reflection
Here are 10 examples of total internal reflection in everyday life.
1. Fiber Optic Cables
A very common example of internal reflection is fiber optics. Fiber optic cables use total internal reflection to transmit information over long distances. The high refractive index of the glass core causes repeated total reflection down the length of the cable.
2. Binoculars and Telescopes
We use binoculars and telescopes in our daily life and school labs. Prisms inside binoculars and telescopes rely on total internal reflection to deviate the path of light and increase the optical tube length in a compact form factor.
3. Diamond Sparkle
When light enters a diamond, it totally reflects internally off the rear facets before exiting the top. This scattering gives diamonds their trademark brilliance.
A periscope is an optical instrument that is used to see around obstacles. It consists of two mirrors that are placed at 90 degrees to each other. Total internal reflection occurs at the surfaces of the mirrors, allowing the periscope to see around corners.
5. Vehicle Reflectors
Glass reflectors on cars and bicycles reflect headlight beams back using total internal reflection to improve visibility at night.
6. Pool Illumination
Swimming pool perimeter lighting submerged in the water uses total internal reflection to channel light through the waterline walls.
7. Sapphire Glass
The durable glass used in watches and smartphones is made of sapphire, which has a high index of refraction for total internal reflection.
8. TIR Switches
Optical switches use total internal reflection at a glass-air interface to switch light paths on and off electronically.
9. Fisheye Lens
A fisheye lens is a camera lens that produces a wide-angle image. The lens is curved so that the light rays that enter the lens are totally internally reflected. This allows the lens to capture a wider field of view.
A fiberscope is a medical instrument that is used to look inside the body. It consists of a long, thin fiber optic cable that is inserted into the body. Total internal reflection occurs along the length of the cable, allowing the doctor to see the inside of the body.
These are just a few examples of total internal reflection in everyday life.