What is a Compound Microscope?
A compound microscope is a microscope fitted with two or more convex lenses. The high magnification produced by these lenses together enables a detailed study of micro-organisms, cells and tissues. These types of microscopes are therefore widely used in scientific and medical research. Zacharias Janssen, a Dutch spectacle maker, invented the compound microscope in 1590. Galileo unveiled his version in 1610. Several other scientists and inventors later helped refine the design and working capabilities of this microscope. The basic design of a compound light microscope consists of convex lenses fitted at either end of a hollow tube. This tube is fitted on an adjustable, rotary nosepiece. There is an adjustable stage under the nosepiece; specimen slides are placed or fitted on this stage for observation through the lenses. The stage has a window or hole in it through which a light source can illuminate the specimen under observation. The light source can be a mirror reflecting natural lig
Used mostly in biology, compound microscopes have two or more double convex lenses. They produce a 2-D slice image of an object, yet can attain a high enough magnification to see a hair strand. Unfortunately, they do not have excellent resolution, so the image may be blurred. On the other hand, stereoscopic microscopes, as the name implies, provide a 3-D picture of bisected items, like muscle tissue or an organ. Compound microscopes are the simplest type of microscope and are found in many classrooms. Compound microscopes are operated entirely by hand and use ordinary ambient light from the sun or light bulb. The specimen is mounted between two glass slides, and the microscope system uses a simple series of magnifying lenses and mirrors to bring the image to the eyepiece, much like a telescope.
• Place a prepared slide onto the stage using the stage clips to secure it. If the microscope has a mechanical stage, allow it to come into contact with the slide. • Always start with the nosepiece in the lowest powered objective. • Turn the focus knobs so that the stage and objective are as close together as they will go. • Turn the illuminator to the “on” position. Light should come from the sub-stage illuminator. • Look through the eyepiece and slowly turn the coarse focus knob so that the stage and objective are moving away from each other. • Continue until the image appears. • Once the image is in focus, use the fine focus (if available) to focus the image clearly. • After the image is in focus, switch to a higher power objective. • Adjust the diaphragm to either Disc or Iris to manipulate the amount of light that passes through the image. This will increase the clarity of your image. • 100X Oil Immersion Objective • Follow above steps until ready to switch to the 100X objective (
