The light microscope, so called because it employs visible light to detect small objects, is probably the most well-known and well-used research tool in biology. Light from an incandescent source is aimed toward a lens beneath the stage called the condenser, through the specimen, through an objective lens, and to the eye through a second magnifying lens, the ocular or eyepiece. We see objects in the light path because natural pigmentation or stains absorb light differentially, or because they are thick enough to absorb a significant amount of light despite being colorless.
Standard Light Microscopy Design
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| H&E stain of the rat esophagus | Normal and stenotic rat iliac artery stained with Verhoeff Van Geison for elastin |