Microscope
When we see through the eyepiece, we see an enlarged image of the
object placed on the clear glass surface. There is a convex lens fitted between
the eyepiece and the glass (picture-2). A mirror is placed below the glass
which can reflect the light of a torch which is shone towards it
(picture-3).This helps us to see thin materials while thick materials can be
seen well by shining the torch through the gap over the glass surface.