Mirror
The mirror is a smooth, reflective surface to form an image. The mirror is known as a kind that can reflect light or shadow. The initial mirror consists of sheets or polished metal sheets, usually silver or brass metal when the resurfaced image is to be seen but also from other metals when only the required light concentration converges. Most modern mirrors consist of a thin layer of aluminum coated on glass sheets. It is a rear posture, where the bounce surface is seen through glass sheets; this makes the mirror stand, but reduces the quality of the mirror due to the addition of the front glass surface refinements. This mirror reverses about 80% of the light. The "rear" mirror is often painted completely black to protect the metal from corrosion. Other telescopes and other equipments use front silvered front windshield, where the surface bounces on the front of the glass, which provides better image quality.