| Dictionary, Encyclopedia and Thesaurus - The Free Dictionary 1,763,186,624 visitors served. |
|
Dictionary/ thesaurus | Medical dictionary | Legal dictionary | Financial dictionary | Acronyms | Idioms | Encyclopedia | Wikipedia encyclopedia | ? |
aperture |
Also found in: Dictionary/thesaurus, Medical, Legal, Wikipedia, Hutchinson | 0.03 sec. |
apertureAn orifice. It often refers to an opening in which light is allowed to pass in optical systems such as cameras and lasers. See f-stop and numerical aperture. aperture Physics a. a usually circular and often variable opening in an optical instrument or device that controls the quantity of radiation entering or leaving it b. the diameter of such an opening aperture [′ap·ə‚chər] (electronics) An opening through which electrons, light, radio waves, or other radiation can pass. (graphic arts) A rectangular cutout on an aperture card. (optics) The diameter of the objective of a telescope or other optical instrument, usually expressed in inches, but sometimes as the angle between lines from the principal focus to opposite ends of a diameter of the objective. How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content. |
|
| ? Mentioned in | ? References in periodicals archive | ||
|---|---|---|---|
| A plain x-ray demonstrated an extremely wide nasal aperture (figure 2). This was then closed and lateralized, providing a much more adequate nasal aperture (figure 4). |
| Encyclopedia |
| Free Tools: |
For surfers:
Free toolbar & extensions |
Word of the Day |
Help
For webmasters: Free content | Linking | Lookup box | Double-click lookup | Partner with us |
|---|