|MadSci Network: Physics|
The types of lenses and mirrors are named concave and convex.
The convex lens and the concave mirror both focus light. They collect light from an area and focus it to a point. The convex lens is used in binoculars and refractive telescopes. The concave mirror is used in a reflective telescope.
The concave lens and the convex mirror defocus light. Convex mirrors are often used where you want to see what's happening over a large area; for example, many motor vehicle drivers have added convex mirrors to allow them to observe other vehicles behind them. The concave lens is normally used for the eyeglasses to correct nearsidedness. Click on the following link to learn more about The Optics of the Eye.
Use any of the WWW search engines with the keywords concave, convex, mirror, lens and you can find much more information.
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