Difference between revisions of "Lens"
(Created page with "==Key Stage 3== ===Meaning=== A lens is a shaped piece of glass, or other transparent material, that can be used to focus an image of an object. =...") |
|||
| Line 5: | Line 5: | ||
===About Lenses=== | ===About Lenses=== | ||
: A [[lens]] can be [[Convex Lens|convex]] or [[Concave Lens|concave]]. | : A [[lens]] can be [[Convex Lens|convex]] or [[Concave Lens|concave]]. | ||
| + | : There is a [[lens]] in the [[eye]] that is used to [[focus]] an [[image]] onto the [[retina]]. | ||
| + | : Glass [[lens]]es can be moved relative to a screen until an [[image]] is [[focus]]ed but the [[lens]] in the [[eye]] can change shape to [[focus]] light. | ||
| + | |||
| + | ==Key Stage 4== | ||
| + | ===Meaning=== | ||
| + | A [[lens]] is a shaped piece of [[glass]], or other [[transparent]] [[material]], that can be used to [[focus]] an [[image]] of an [[object]]. | ||
| + | |||
| + | ===About Lenses=== | ||
| + | : A [[lens]] can be [[Convex Lens|convex]], also called a [[Converging Lens|converging lens]] or [[Concave Lens|concave]], also called a [[Diverging Lens|diverging lens]]. | ||
| + | : [[Lens]]es can be used to create a [[Real Image|real image]] by [[focus]]sing light onto a [[screen]], or they can create a [[Virtual Image|virtual image]] by looking through the [[lens]]. | ||
| + | : The shape of the [[lens]] determines its [[Focal Length|focal length]]. For a [[Convex Lens|convex lens]] ([[Converging Lens|converging lens]]) the [[Focal Length|focal length]] can be found by [[focus]]sing the [[image]] of a "distant object" onto a [[screen]]. The distance between the [[screen]] and [[lens]] is the [[Focal Length|focal length]]. | ||
: There is a [[lens]] in the [[eye]] that is used to [[focus]] an [[image]] onto the [[retina]]. | : There is a [[lens]] in the [[eye]] that is used to [[focus]] an [[image]] onto the [[retina]]. | ||
: Glass [[lens]]es can be moved relative to a screen until an [[image]] is [[focus]]ed but the [[lens]] in the [[eye]] can change shape to [[focus]] light. | : Glass [[lens]]es can be moved relative to a screen until an [[image]] is [[focus]]ed but the [[lens]] in the [[eye]] can change shape to [[focus]] light. | ||
Revision as of 09:23, 24 February 2019
Key Stage 3
Meaning
A lens is a shaped piece of glass, or other transparent material, that can be used to focus an image of an object.
About Lenses
- A lens can be convex or concave.
- There is a lens in the eye that is used to focus an image onto the retina.
- Glass lenses can be moved relative to a screen until an image is focused but the lens in the eye can change shape to focus light.
Key Stage 4
Meaning
A lens is a shaped piece of glass, or other transparent material, that can be used to focus an image of an object.
About Lenses
- A lens can be convex, also called a converging lens or concave, also called a diverging lens.
- Lenses can be used to create a real image by focussing light onto a screen, or they can create a virtual image by looking through the lens.
- The shape of the lens determines its focal length. For a convex lens (converging lens) the focal length can be found by focussing the image of a "distant object" onto a screen. The distance between the screen and lens is the focal length.
- There is a lens in the eye that is used to focus an image onto the retina.
- Glass lenses can be moved relative to a screen until an image is focused but the lens in the eye can change shape to focus light.