The Uses of Lenses in Optical Devices Simple MicroscopeA magnifying glass is the simplest microscope. It consists of a single convex lens with short focal length. When the magnifying glass is held near to the eye and the object is placed inside its focal length (u < f), a virtual, magnified and upright image is produced. A sharper and larger image is seen at … [Read more...] about The Uses of Lenses in Optical Devices