The magnifying glass is the simplest optical observation instrument. It is also called a magnifying glass.
A magnifying glass consists of a converging lens with focal length in the order of centimeters, able to combine a virtual image, direct and larger than the object.
However, this instrument is effective only when the observed object is placed between the main object focus and the optical center.
When a magnifying glass is attached to a holder it is called simple microscope.