December 8, 2006 7:35am CST
how often you look at the mirror
8 Dec 06
A mirror is a device whose surface has good specular reflection; that is, it is smooth enough to form an image. The most familiar type of mirror is the plane mirror, which has a flat surface. Curved mirrors are also used, to produce magnified or demagnified images. The most common use of mirrors is in the home for personal grooming, but mirrors are also used in scientific apparatus such as telescopes and lasers, and in industrial machinery. Most mirrors are designed for visible light, however, mirrors designed for other wavelengths of electromagnetic radiation are also used, especially in optical instruments.