CHAPTER 19 - Spherical Mirrors

Abstract

Publisher Summary This chapter discusses various properties of spherical mirrors. Spherical mirrors are those types of mirrors whose reflecting surfaces form a part of the surface of a sphere. In the convex type, the reflection takes place on the outside surface of the sphere while in the concave type reflection is from the inside surface. The path of a ray of light is always reversible. Thus, an incident ray passing through the principal focus of a concave mirror is reflected parallel to the principal axis. The fundamental property of a convex, or diverging, mirror is to make incident divergent beams more divergent. Use of spherometer is a nonoptical method suitable for both types of mirror. Concave mirrors are used as magnifiers as in shaving mirrors, dentists' inspection mirrors, etc., in which cases the object must be closer to the mirror than the principal focus. Convex mirrors find less application than concave mirrors. They are used as driving mirrors because they give a wide field of view, that is, the diminished image formed is of a large area of the surroundings. They are also used as ornamental mirrors in homes and find occasional use in telescopes and other optical instruments.