Transparency (optics)

Transparency (optics)

In optics, transparency (also called pellucidity) is the material property of allowing light to pass through. In mineralogy, another term for this property is diaphaneity. The opposite property is opacity. Transparent materials are clear: they can be seen through. Translucent materials allow light to pass through them only diffusely: they cannot be seen through. Translucency does not include see-through colored objects such as (for instance) emerald in its cut state (which is transparent) but does include things such as frosted glass which allow light to come through but no distinct images.

Transparency

Though transparency usually refers to visible light in common usage, it may correctly be used to refer to any type of radiation. For example, flesh is transparent to X-rays, while bone is not, making X-ray imaging useful for medicine.

Examples of transparent materials are air and some other gases, liquid such as water, most glasses, and plastics such as Perspex. Where the degree of transparency varies according to the wavelength of the light, the image seen through the material is tinted. This may be due to certain metallic oxide molecules in glass, or larger colored particles, as in a thin smoke. If many such particles are present the material may become opaque, as in thick smoke.

From electrodynamics it results that only a vacuum is really transparent in the strict meaning, any matter has a certain absorption for electromagnetic waves.

There are transparent glass walls that can be made opaque by the application of an electric charge, a technology known as electrochromics.

Certain crystals are transparent because there are straight lines through the crystal structure. Light passes unobstructed along these lines.

There is a theory which predicts the absorption of photons by a material. See absorption (optics) and absorption spectroscopy.

ee also

*Transmittance
*Electromagnetically induced transparency
*Transparent alumina
*Transparent aluminum
*List of optical topics
*birefringence


Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать реферат

Look at other dictionaries:

  • Transparency — may refer to:*Transparency (optics), the physical property of allowing the transmission of light through a materialLiteral uses: *Electromagnetically induced transparency, an effect in which a medium that is normally opaque at a particular… …   Wikipedia

  • Transparency and translucency — Diaphanes redirects here. For the genus of firefly, see Diaphanes (beetle). Translucence redirects here. For other uses, see Translucence (disambiguation). Translucent redirects here. For the Japanese manga series, see Translucent (manga).… …   Wikipedia

  • optics — /op tiks/, n. (used with a sing. v.) the branch of physical science that deals with the properties and phenomena of both visible and invisible light and with vision. [1605 15; < ML optica < Gk optiká, n. use of neut. pl. of OPTIKÓS; see OPTIC,… …   Universalium

  • Index of optics articles — Optics is the branch of physics which involves the behavior and properties of light, including its interactions with matter and the construction of instruments that use or detect it.[1] Optics usually describes the behavior of visible,… …   Wikipedia

  • Electromagnetically induced transparency — The effect of EIT on a typical absorption line. A weak probe normally experiences absorption shown in blue. A second coupling beam induces EIT and creates a window in the absorption region (red). This plot is a computer simulation of EIT in an… …   Wikipedia

  • Fourier optics — is the study of classical optics using techniques involving Fourier transforms and can be seen as an extension of the Huygens Fresnel principle. The underlying theorem that light waves can be described as made up of sinusoidal waves, in a manner… …   Wikipedia

  • Rendering (computer graphics) — Not to be confused with 3D rendering. A variety of rendering techniques applied to a single 3D scene …   Wikipedia

  • List of optical topics — Probably some Wikipedia articles on topics in optics are not yet listed on this page. If you cannot find the topic you are interested in on this page, the article may nonetheless exist; you can try to find it using the Search box, or look in and… …   Wikipedia

  • Optical fiber — A bundle of optical fibers A TOSLINK fiber optic audio c …   Wikipedia

  • eye, human — ▪ anatomy Introduction  specialized sense organ capable of receiving visual images, which are then carried to the brain. Anatomy of the visual apparatus Structures auxiliary to the eye The orbit       The eye is protected from mechanical injury… …   Universalium

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”