FACTOID # 27: If you're itching to live in a trailer park, hitch up your home and head to South Carolina, where a whopping 18% of residences are mobile homes.
 
 Home   Encyclopedia   Statistics   States A-Z   Flags   Maps   FAQ   About 
   
 
WHAT'S NEW
RELATED ARTICLES
People who viewed "Collimator" also viewed:
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > Collimator
How a lead collimator filters a stream of rays. Top: without a collimator. Bottom: with a collimator.
How a lead collimator filters a stream of rays. Top: without a collimator. Bottom: with a collimator.

A collimator is a device used to filter a stream of rays (such as X-rays) so that only those travelling parallel to each other in a certain direction are allowed through. The picture shows a lead collimator used in X-ray machines. The image will be recorded on the plate at the left of the picture. Without a collimator (top picture) rays from all directions will be recorded; for example, a ray that has passed through the top of the specimen but happens to be travelling in a downwards direction may be recorded at the bottom of the plate. This will not produce a readable image. Basic diagram of how a lead collimator works. ... In the NATO phonetic alphabet, X-ray represents the letter X. An X-ray picture (radiograph) taken by Röntgen An X-ray is a form of electromagnetic radiation with a wavelength approximately in the range of 5 pm to 10 nanometers (corresponding to frequencies in the range 30 PHz...


In the bottom picture a lead collimator has been added. Effectively, this is a thick sheet of lead with many tiny holes bored through it. Only rays travelling at 90° will pass through - any others will be absorbed by hitting the side of a passage. This ensures that rays are recorded in their proper place on the plate, producing a clear image.


Collimators may be used with laser diodes. A laser diode is a laser where the active medium is a semiconductor p-n junction similar to that found in a light-emitting diode. ...


Collimating lenses may also be used in optical systems to make rays of light parallel (see also Collimating lens). A collimating lens is a lens used to gather together a parallel beam of light. ...


Collimators are also used with radiation detectors in nuclear power stations for monitoring sources of radioactivity.


  Results from FactBites:
 
Collimated light - Wikipedia, the free encyclopedia (267 words)
Collimated light is light whose rays are parallel and thus has a plane wavefront.
Light can be collimated by a number of processes, the easiest being to shine it on a parabolic concave mirror with the source at the focus.
Laser light is often collimated due to being formed in a chamber between two such mirrors, in addition to being coherent.
Collimated - definition of Collimated in Encyclopedia (215 words)
Collimated light is light whose rays are parallel.
Light can be collimated by a number of processes, the easiest being to shine it on a concave mirror with the source at the focus.
The light from stars, including the sun, can be considered collimated (for almost any purpose) because they are so far away.
  More results at FactBites »

 
 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:

 


Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m