OPTICAL MICROSCOPY Davidson and Abramowitz OPTICAL MICROSCOPY Michael W. Davidson1 and Mortimer Abramowitz2 1 National High Magnetic Field Laboratory, The Florida State University, 1800 E. Paul Dirac Dr., Tallahassee, Florida 32306,
[email protected], http://microscopy.fsu.edu 2 Olympus America, Inc., 2 Corporate Center Dr., Melville, New York 11747,
[email protected], http://www.olympus.com Keywords: microscopy, phase contrast, differential interference contrast, DIC, polarized light, Hoffman modulation contrast, photomicrography, fluorescence microscopy, numerical aperture, CCD electronic cameras, CMOS active pixel sensors, darkfield microscopy, Rheinberg illumination. Introduction binocular microscopes with image-erecting prisms, and the first stereomicroscope (14). The past decade has witnessed an enormous growth in Early in the twentieth century, microscope the application of optical microscopy for micron and sub- manufacturers began parfocalizing objectives, allowing the micron level investigations in a wide variety of disciplines image to remain in focus when the microscopist exchanged (reviewed in references 1-5). Rapid development of new objectives on the rotating nosepiece. In 1824, Zeiss fluorescent labels has accelerated the expansion of introduced a LeChatelier-style metallograph with infinity- fluorescence microscopy in laboratory applications and corrected optics, but this method of correction would not research (6-8). Advances in digital imaging and analysis see widespread application for another 60 years. have