ABSTRACT
A microscope is an instrument used to see objects that are too small for the naked eye. The most common is the optical microscope, which uses light to image the sample. Dark field microscopy is used to enhance the contrast in unstained and transparent specimens. Magnifying glasses enlarge images by small degrees, blurring the image around the edges as lens magnification increases. Microscopes combine two lenses, requiring adjustments in depth of field and magnification to observe small objects clearly. A confocal configuration can provide, among other several benefits in optical microscopy, the possibility of recovering three-dimensional images of thick samples, such as biological tissue. One of the main advantages of adapting a confocal configuration in a microscopy system can be exemplified when discussing microscopy by fluorescence. The image formation of a confocal microscope can be approximated by using Fresnel integrals.
