Compound microscopes have a combination of lenses that enhance magnification and resolution.
The sample or object to be examined is usually mounted on a clear glass slide and placed on the sample stage between the condenser and objective.
The visible beam from the bottom is focused onto the sample by a condenser.
The objective lens picks up the light transmitted by the specimen and creates a magnified image of the specimen within the lens tube, called the master image. The image is again magnified by the eyepiece or eyepiece.
When higher magnification is required, rotate the nosepiece after focusing at low power to align the higher power objective (usually 45X) with the illuminated portion of the slide.
Sometimes very high magnification is required (for example, to view bacterial cells). In this case, an oil immersion objective (usually 100X) will be used.
Ordinary optical microscopes are also called brightfield microscopes because the images are produced in a bright field of illumination. The image appears darker because the specimen or object is denser and somewhat opaque than its surroundings. Part of the light passing through or object is absorbed.
