How Can Lenses Act Like Magnifiers?
Magnifying lenses are constructed of convex lenses, typically made of some type of clear glass or plastic. In most cases, images are magnified either by a microscope or by a magnifying glass.
Other People Are Reading
-
Bending Light
-
When the light that is reflected off of an object makes a transition from one medium (air) to the other (a lens), it bends. How much the light bends is determined by the intensity of the curvature of the lens. Magnifying lenses are called convex lenses. Convex lenses are thick in their center and thin on their outsides. They bend light to a central focal point that produces a magnified representation of the image.
Convex vs. Concave Lenses
-
While convex lenses have a thick center and thin edges, concave lenses are simply the opposite. The thin center and thick edges on a concave lens spread out the rays of light that are refracted through them. As opposed to convex lenses, the image formed by a concave lens is a smaller representation of the actual object.
-
Strength
-
The strength of a magnifying lens depends on where it is placed in relation to the viewer and the object. Common magnifying glasses just about double the appearance of the size of the object. Complex combinations of lenses can make objects seem several thousand times larger than they actually are.
Focus
-
In order to focus properly with a magnifying lens, users move the lens slowly back and forth between the eye and the object until they find the correct relative position. When the lens is too close or far from either the eye or the object, the object can appear blurry and not magnified at all.
Lenses and Eyes
-
For most people, lenses magnify an object between one and two times its actual size, but for someone with very poor eyesight the object can appear up to eight times larger. This is due to the fact the poor eyes have a longer focus point, the spot where light rays coming from a point on the object meet, than good eyes. In other words, poor eyes must be further away from an object in order for the object to be clear and not blurry.
-
