| Date | Text | |
|---|---|---|
23 Jan 1840
Ernst Abbe |
birth Ernst Abbe Born 23 Jan 1840; died 14 Jan 1905 at age 64. German physicist who established a technical and theoretical foundation for the design of optical instruments. The Abbe sine condition enabled designing lenses without spherical aberation's image distortion. He invented the apochromatic lens system (1868), and added the Abbe condenser lens to improve illumination for the microscope (1870). He used homogenous immersion of specimen and microscope objective in cedar oil with matching refractive index to give higher magnification. He invented the Abbe refractometer to measure a refractive index. From 1866, he collaborated with Carl Zeiss to produce high quality optical instruments. He became sole owner of the Zeiss optical works in 1888. From 1878, he also was director of the University of Jena astronomical and meteorological observatories. |
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