Introduction
The previous chapter dealt with the refraction of light by lenses and also about the formation of various types of images by a lens for different positions of the object. In this chapter let us find out how lenses are used in optical instruments like microscopes and telescopes to obtain magnified image of an object.
Microscopes
A microscope is an optical device which produces a highly magnified image of very small object such as micro-organisms. Based on the design, there are two types of microscopes. They are, simple microscope and compound microscopes.
Simple Microscope
A simple microscope is nothing but a single biconvex lens. It is referred to as magnifying glass.
Compound Microscope
A compound microscope is an optical instrument which is used to magnify very small objects like blood cells, bacteria which otherwise cannot be seen with the naked eye.
Telescopes
Telescope is an optical instrument which is used for viewing heavenly bodies and distant objects.
Astronomical Telescope
This type of telescope is used to view heavenly bodies like stars, planets and satellites.
Summary
Microscope is an optical device which produces a highly magnified image of a very small object.
