STP257: Measurement with Phase and Interference Microscopes

    Richards, Oscar W.
    Chief Biologist, American Optical Co., Southbridge, Mass.

    Pages: 13    Published: Jan 1959


    Errors of measurement in visual microscopy are mentioned briefly. The phase microscope can measure the size of transparent specimens, is useful for counting and a good null method for the measurement of refractive index. Precautions necessary with absorbing specimens are discussed. The interference microscope can measure optical path in transparent and nearly transparent specimens and, from the path differences and refractive index, thickness and mass of reasonably homogeneous specimens may be calculated. The precision of the AO-Baker interference microscope is described, and errors of the instrument and the observer are discussed. An appendix summarizes the precision of thickness measurements of microscopical specimens, and a nomogram is included to aid computations.

    Paper ID: STP46948S

    Committee/Subcommittee: E42.15

    DOI: 10.1520/STP46948S

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