To magnify and observe things that are too small for the naked eye to see, scientists use the microscope. There is a wide range of microscopes that exist in biology and medicine that are specific to produce images of individual molecules and also the entire living organisms. The Fluorescent microscope provides students, teachers, scientists, and researchers the means to observe and evaluate the intracellular distribution of specific molecules. A biological tissue is composed of cells. The cells are well organized and compartmentalized. An entire cell is very small measuring less than 1/10th the diameter of a human hair. Without the aid of fluorescent microscopes, it is impossible to observe these cell structures. A lot can be studied about the role of molecules from their cellular location, and from their association with other molecules with known functions. A fluorescent microscope could show a fluorescence image of a cell that has been marked with a probe that fluoresces different colors for different parts.

The image from a fluorescent microscope is different from the images seen in other microscopes since it has a black background. The explanation is that the fluorescent microscope is designed to light up the cells with a color of light that stimulates the fluorescence, and to expose only the colors of the fluorescence itself. One example is when blue light is being absorbed by a molecule and then stimulates red fluorescence. Sometimes, colored optical filters are utilized to lead blue light onto the cells but only allow the red fluorescence to pass. The observer will not see any of the illuminating light only the fluorescence.

Confocal microscopes, a new type of fluorescent microscope, have been newly developed. What it does is scan over a sample using laser beams to collect very clear 3D images of cells. It makes use of a laser which excites fluorescent molecules present in cells or molecules attached inside cells. Using the fluorescent microscope, fluorescent image is magnified and then measured by a “detector”. A pinhole is placed in front of the detector. It only permits light from the focal point of the lens to pass. The word “confocal” microscope was derived because the pinhole is in “conjugate” to the focal point. What this means is all the light that arrives at the detector is in focus. In conventional microscope, when the light is out of focus it results to a blurred image. The laser beam is scanned across the specimen by mirrors to produce an image. The image must first be assembled in a computer or else it does not exist. Images from different layers of a thick specimen can be generated by moving the level of the pinhole vertically. The final image can be then be recreated in 3-D by a computer.

Confocal microscopy has altered biological imaging of thick structures. In the past, scientists and researchers have to cut these structures into slices and manually reconstruct the images from these slices into 3D. The confocal microscope can now do all this for them via computer. Living organisms can also be used as samples. These advantages have made it a necessary tool for biomedical research.