Staining increases contrast. Light microscope contains single whereas compound microscope uses two lenses, ocular and objective lenses. Immersion oil increases the microscope's resolving power by replacing the air and replacing the air gap between the immersion objective lens and cover glass with a high refractive index medium. Another type of microscope Is called fluorescence microscope. The reflected light passes through the objective, focusing onto the fluorescent specimen. It is more reliable and widely used to observe the localization of molecules within cells and cells within tissues. Electron microscope- a kind of microscope that produces higher resolution images than a standard microscope. It is used to examine the whole cell and the subcellular structure.