An optical microscope or a light microscope magnifies objects which are far too small to be seen by the naked eye. In an optical microscope, light must gathered from a small area of a well illuminated thin specimen in close distance. As a result, an optical microscope employs small and spherical objective lenses. This allows for a much shorter focal length and hence a much shorter distance is needed within the tube of the microscope to bring the image of the object into focus. A second lens normally referred to as the eyepiece or an ocular lens is used to magnify the image as the image is brought to the eye.