the critical angle of an interface between a dense medium and air is angle of incidence.
the critical angle of an interface between a dense medium and air is angle of incidence.
critical angle of an interface between a dense medium and air?
angle of incidence
a beam of light travelling through a medium of refractive index n incident on an interface with a second medium of refractive index n (with nn) will be partially transmitted through the second medium and partially reflected back through the first medium if the angle of incidence is less than the critical angle. at the critical angle, the incident beam will be refracted tangent to the interface (i.e. it will travel along the boundary between the two media). at an angle greater than the critical angle (when the incident beam is nearly parallel to the interface) the light will be completely reflected within the first medium, a condition known as total internal reflection. in the case of pstm, the first medium is a prism, typically made of glass, and the second medium is the air above the prism.
photon scanning microscopy
fiber-optic cables use total internal reflection to carry information. when light travels from one medium to another it is refracted. if the light is traveling from a less dense medium to a dense medium it is refracted away from the normal. the opposite applies if the light is traveling from a dense medium to a less dense medium. in optic cables, light travels through the dense glass core (high refractive index) by constantly reflecting from the less dense cladding (lower refractive index). this happens because the surface of the core acts like a perfect mirror and the angle of the light is always larger than the critical angle.
fiberscope