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The reflection of Mount Hood in Mirror Lake.
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. Common examples include the reflection of light, sound and water waves. The law of reflection says that for specular reflection the angle at which the wave is incident on the surface equals the angle at which it is reflected. Mirrors exhibit specular reflection.
In acoustics, reflection causes echoes and is used in sonar. In geology, it is important in the study of seismic waves. Reflection is observed with surface waves in bodies of water. Reflection is observed with many types of electromagnetic wave, besides visible light. Reflection of VHF and higher frequencies is important for radio transmission and for radar. Even hard X-rays and gamma rays can be reflected at shallow angles with special "grazing" mirrors.
Contents [hide]
1 Reflection of light
1.1 Laws of reflection
1.1.1 Mechanism
1.2 Diffuse reflection
1.3 Retroreflection
1.4 Multiple reflections
1.5 Complex conjugate reflection
2 Other types of reflection
2.1 Neutron reflection
2.2 Sound reflection
2.3 Seismic reflection
3 See also
4 References
5 External links
Reflection of light[edit]
Double reflection: The sun is reflected in the water, which is reflected in the paddle.
Reflection of light is either specular (mirror-like) or diffuse (retaining the energy, but losing the image) depending on the nature of the interface. Furthermore, if the interface is between a dielectric and a conductor, the phase of the reflected wave is retained, otherwise if the interface is between two dielectrics, the phase may be retained or inverted, depending on the indices of refraction.[citation needed]
A mirror provides the most common model for specular light reflection, and typically consists of a glass sheet with a
References: Jump up ^ M. Iona (1982). "Virtual mirrors". Physics Teacher 20: 278. Bibcode:1982PhTea..20..278G. doi:10.1119/1.2341067. Jump up ^ I. Moreno (2010). "Output irradiance of tapered lightpipes". JOSA A 27 (9): 1985. Bibcode:2010JOSAA..27.1985M. doi:10.1364/JOSAA.27.001985.