Question

Whats the difference between mirror nd lens?

Answer 1

lens have 2 Focal points 1 on either side of the length of concave mirror convert to a Focal Point .4 lenses light converges to a point for a convex lens convex mirror diverges light as does a concave lens .
is the one which refracrt light and mirror reflect light .in order to impose the picture over a specified screen in proper aspect ratio with minimised chromatic aberration lenses are used .what Mirrors are used in viewfinder reflect the image from lens to viewfinder