Three optical instruments are cameras, microscopes and telescopes.
Cameras-
Cameras are optical devices which focus light on a piece of film to record and allow user to record an image of an object, either on photo paper or digitally.
Microscope-
A microscope is an optical instrument which allows people to see enlarged images of objects that are very small such as mineral samples or animal or plant cells, typically magnified several hundred times.
Telescope-
A telescope is an optical instrument which allows people to see objects that are far away and aids in the observation of remote objects by collecting electromagnetic radiation.