Question

What are the mirrors used in astronomical telescopes​

Answer 1

Reflectors use a concave mirror as its primary objective to focus the incoming light (same optical focusing effect as a convex lens). The mirror is coated on the surface of the glass, called a First Surface Mirror; the coating is usually molecules-thick coating of Aluminum or Silver.

Answer 2

Answer:

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Reflectors use a concave mirror as its primary objective to focus the incoming light (same optical focusing effect as a convex lens). The mirror is coated on the surface of the glass, called a First Surface Mirror; the coating is usually molecules-thick coating of Aluminum or Silver.