kokonaisheijastuksella

Kokonaisheijastus is a Finnish term that translates to total internal reflection in English. This optical phenomenon occurs when a light ray travels from a denser medium to a less dense medium at an angle of incidence greater than or equal to the critical angle. When this condition is met, the light ray does not refract into the less dense medium but is instead completely reflected back into the denser medium.

The critical angle is dependent on the refractive indices of the two media involved. Specifically, it is the angle of incidence for which the angle of refraction is 90 degrees. If the angle of incidence exceeds this value, total internal reflection takes place. This principle is fundamental to the operation of various optical devices.

Fiberscopes and optical fibers, for instance, rely on total internal reflection to transmit light signals over long distances with minimal loss. Light entering the fiber at an appropriate angle undergoes repeated total internal reflections along its length, effectively guiding the light. Prism binoculars also utilize total internal reflection to redirect light paths and magnify images. This phenomenon has practical applications in telecommunications, medical imaging, and scientific instrumentation.