what is the difference between concave and convex lenses?

Answer 1

concave is hollowed out like a shallow bowl, convex bulges outward. As an example, magnifying glasses are double convex.


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Answer 2

A lens is a device that causes light to either converge and concentrate or to diverge, usually formed from a piece of shaped glass. Analogous devices used with other types of electromagnetic radiation are also called lenses: for instance, a microwave lens can be made from paraffin wax.

Types of lenses
Lenses are classified by the curvature of the two optical surfaces. A lens is biconvex (or just convex) if both surfaces are convex, likewise, a lens with two concave surfaces is biconcave (or just concave). If one of the surfaces is flat, the lens is plano-convex or plano-concave depending on the curvature of the other surface. A lens with one convex and one concave side is convex-concave, and in this case if both curvatures are equal it is a meniscus lens. (Sometimes, meniscus lens can refer to any lens of the convex-concave type).

If the lens is biconvex or plano-convex, a collimated or parallel beam of light travelling parallel to the lens axis and passing through the lens will be converged (or focused) to a spot on the axis, at a certain distance behind the lens (known as the focal length). In this case, the lens is called a positive or converging lens.

If the lens is biconcave or plano-concave, a collimated beam of light passing through the lens is diverged (spread); the lens is thus called a negative or diverging lens. The beam after passing through the lens appears to be emanating from a particular point on the axis in front of the lens; the distance from this point to the lens is also known as the focal length, although it is negative with respect to the focal length of a converging lens.

If the lens is convex-concave, whether it is converging or diverging depends on the relative curvatures of the two surfaces. If the curvatures are equal (a meniscus lens), then the beam is neither converged nor diverged.

You could get more information from the link below...

Answer 3

Concave lenses bend inwards like so : ( Convex bend outwards like so: ) Reflections in concave (like on a spoon) turn the incorrect way up. Reflections in convex do not (it would be any opposite direction around, get a spoon and look in it)

Answer 4

Concave curves inward, convex curves outward. The effects of light passing through these and other types: biconvex, plano-convex, biconcave, plano-concave, etc. can be found at -

http://en.wikipedia.org/wiki/Lens_%28optics%29#Types_of_lenses

Answer 5

Convex lenses are curved outward and they cause light that goes trough it to converge or concentrate on one spot. Think of a magnifying glass that is used to burn something. The light that goes through it concentrates or diverges so you can burn things. :-)


Concave lenses are are curved inward and when light goes through it it diverges or spreads out. Think of a flashlight. The light comes from a smal bulb goes through and spreads out to a bigger beam on the other side.

Click on the image link on this page...

http://www.tiscali.co.uk/reference/encyclopaedia/hutchinson/m0031043.html

Answer 6

a concave lens in thin in the center and thick at the edges used for people who are nearsighted or Myopic, a convex lens is thick in the center thin at the edge and used for people who are farsighted or hyperopic.
Hope I helped :o)

Answer 7

the way they curve is the only difference... concave I believe curves in i.e.: from the side it would look like )( or )| while convex looks like () or (|

I may have those backwards though...