Page 95 - Fundamentals of Light Microscopy and Electronic Imaging

78 DIFFRACTION AND INTERFERENCE IN IMAGE FORMATION

Figure 5-13
Ernst Abbe, 1840–1905. Principles of microscope and objective lens design, the theory of
image formation in the microscope, and standardized lens manufacturing procedures all
trace their beginnings to the work of Ernst Abbe and his collaborations with Carl Zeiss in
Jena, Germany, in the 1860s. Until then, lens making was an art and a craft, but the new
industrial philosophy demanded technical perfection, lens designs based on theory and
research, and improvements in raw materials. At Abbe’s initiative, lens curvatures were
examined using an interference test with Newton’s rings, and lens designs were based on
Abbe’s sine-squared condition to remove aberrations. He created the first planachromatic
lens, and after much research, the apochromatic lens, which was commercially sold in 1886.
After many false starts over a 20-year period, the research-theory-testing approach for
manufacturing lenses proved to be successful. These improvements and new photographic
lens designs required new types of glass with values of refractive index and color dispersion
that were not then available. Abbe and Zeiss won grants and developed new glasses in
collaborations with the industrialist, Otto Schott, owner of the Jena Glassworks. Other