A reflecting telescope.
Concave means bulging inward - reflecting telescopes use this sort of mirror. The first telescope designed to use one was invented by Isaac Newton and they are therefore called "Newtonian" telescopes.
a concave mirror
It uses a concave mirror in order for the light to be concentrated to point forward.
Some practical uses for concave and convex mirrors are in medical instruments, car mirrors, and telescopes.
A reflecting telescope is different from a refracting telescope because a reflecting telescope uses a concave lens, a plane mirror, and a convex lens. While a refracting telescope uses two lens.
Magnifying mirrors, make-up mirrors, telescopes
concave mirror shows the image real and magnified........when a dentist uses a concave mirror, he/she places the mirror such that the teeth falls on the focus of the mirror due to which the wound can be easily detected and can be treated as per its treatment
Reflecting Telescopes -uses a single or combination of curved mirrors to bring light to a focus and make an image.
all telescopes use a mirror.
A film artist typically uses a concave mirror when applying make-up. The reason for this is that a concave mirror produces an erect, virtual and highly magnified image.
Your question makes no sense
I think to focus light on the specimen slide.