focusing mirrors | concave mirrors

Focusing mirrors (concave mirrors) are characterized by one concave surface with a high reflection coating. The reflective coating allows focusing of the light beam. Most common coating materials include Al, Au or Ag.

Applications of focusing mirrors – examples

Mirrors are found most useful when refractive optics (e.g. lenses) cannot be used due to too high energy of a light beam in lasers. Another example requirement for a concave mirror is when no chromatic aberration is allowed in a broad spectral range. Yet another common use case is tightness optimization of the optical system.

Concave mirrors can be used similarly to focusing lenses. Type of image created by a focusing mirror depends on radius of the concave surface as well as on the distance from an object to the mirror. Hence, concave mirrors can create:
-imaginary or real images,
-reversible or simple images,
-images magnified, minimized or equal in dimensions compated to the object size.