Abbe, Ernst

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Abbe, Ernst (1840-1905) was a professor of optics who worked with Schott, the glassmaker, and Zeiss, the lensmaker, in Jena. 

It was learned very early that the angular aperture of the substage condenser controls specimen contrast. Decreasing that aperture, usually with a continuously adjustable iris diaphram, greatly increases contrast. It was not, however, appreciated fully until Ernst Abbe s classic contributions (7,8) in the period ca 1880—1889 that decreasing the aperture to increase contrast also decreases the resolving power of the microscope. 

Theory The initial understanding of the refraction of light dates back to Maxwell s study of electromagnetic radiation. Ernst Abbe invented the first commercial refractometer in 1889 and many refractometers still use essentially the same design. 

Three major advancements in resolution have occurred since Hookes s discovery of the optical microscope in 1665 [46]. In 1873, Ernst Abbe established fundamental criteria for the resolution limit in optical microscopy [47], which did not exceed the range of a couple of 100 nanometers even after the introduction of the confocal optical microscope [43,48]. The invention of the transmission electron microscope by Ernst Ruska in 1933 extended the resolution of microscopes to the nanometer scale [49]. Finally, scanning tunnelling microscopy introduced, by Binnig and Rohrer in 1981, made a breakthrough when atomic... 

These three factors can be combined into a single equation (Ernst Abbe 1840-1905) ... 

The factor 1.22 in Eq. 2.1 was empirically derived by Rayleigh. It may be derived from the radius of the circle, known as the Airy disk, from the optical transfer function. In 1873, the German physicist Ernst Karl Abbe (1840-1905) showed that the numerical... 

Chapter 1 is concerned with the fundamental principles of image formation by a lens. These principles were first formulated by Ernst Abbe in 1873 and are basic to the chapters that follow. According to the Abbe theory, the image of an illuminated object is the result of a twofold diffraction process. First, the Fraunhofer diffraction pattern of the object is formed in the back focal plane of the lens. Second, the light waves travel... 

Figure 3.28 Ernst Abbe, who developed the Abbe sine condition—a design specification derived from wave theory for ensuring good image quality in microscopes. He also transformed the Zeiss optical company into the Carl Zeiss Foundation in 1889. The greatness of this company was not only in the quality of its optical products, but equally in the care it took of its workers at a time when exploitation and oppressive poverty were the rule. (Courtesy of the Carl Zeiss Archives.)...

The roots of immersion lithography date back to the invention of immersion microscopy by Ernst Abbe (1840 1905) in 1878, since he sought ways to increase the resolving power of optical... 

Otto Schott (1851-1935), Ernst Abbe (1840-1905), Carl Zeiss, and Roderick Zeiss established the Glastechnisches Laboratorium Schott und Genossen, which later became the Jenaer Glaswerk Schott und Gen and in 1952 the Schott Glaswerke. This company is now the leading European glass company. 

B.R. Masters, Ernst Abbe and the foundations of scientific microscopes. Opt. Photonics. 

In 1873, Ernst Abbe established the resolution limit of optical microscopes The minimum distance, d, between two structural elements to be imaged as two objects instead of one is given by d = A/(2 NA), where X is the wavelength of light and NA the numerieal aperture of the objective lens. The physical root for resolution limit is related to optical diffraction and loss of evanescent waves in far-field the evaneseent waves carry high-frequency subwavelength spatial information of an object and decay exponentially with distance from the objeet. With white lights, optical microscope resolution is limited at about 200-250 nm. For about one hundred years, the Abbe criterion was considered the fundamental limit of optical microscope resolution. 

Glaswerk Wertheim, Ernst-Abbe-Strasse 1, D-6980 Wertheim/Main, FRG. The Max-Planck-Institut fur Strahlenchemie will pass on tube material at cost. 

One of the most important fundamental interactions between a specimen and the imaging radiation is that of diffraction, a phenomenon that results from the wave nature of the imaging agent. Diffraction occurs whenever a wave motion encounters an object, but its effects assume particular importance in microscopy, where the dimensions of features being imaged may be close to the wavelength. The role of diffraction as the limiting factor in the performance of the microscope was first elucidated by Ernst Abbe in 1873. 

In the late nineteenth century. Dr Ernst Abbe and Dr Carl Zeiss worked together to create one of the world s foremost precision optics companies. The Abbe principle resulted in observations about measurement errors. 

Diffraction is crucially important in optics, since light cannot be focused to a smaller size than the diffraction limit, first defined by the German physicist Ernst Abbe as ... 

The investment of resources by Schott and its employees to produce the Schott Series is, as already stated, necessary for the interdisciplinary dialogue and collaboration that are traditional at Schott. A model we still find exemplary today of a fruitful dialogue between fundamental research, glass research, and glass manufacture was achieved in the collaboration of Ernst Abbe, Otto Schott, and Carl Zeiss. It resulted in the manufacture of optical microscopes that realized in practice the maximum theoretically achievable resolution. It was especially such experiences that shaped the formulation of the founding statute of the Carl Zeiss Foundation, and the initiative for the Schott Series is in accord with the commitment expressed in the founding statute to promote methodical scientific studies . 

The classical meftiod to measure ftie index of refraction of transparent materials is based on total internal refraction. The instrument based on this method is the Abbe refractometer designed by Ernst Abbe in the early 1900s. This typically yields index accuracy of two units in the fourth decimal place, but it works only for materials where the refractive index is smaller than the glass prism (about n = 1.89). To measure anisotropic fluids with the Abbe refractometer, the material has to be uniformly (usually homeotropically) aligned between the prisms. Ordinary and extraordinary rays can be selected by using polarization filters polarized perpendicular and along the optic axis, respectively. 

The next set of nmnbers in the examples, 0.25 and 0.65, respectively, is the nmnerical aperture (NA), a measure of the light-gathering capabihty of the objective and, therefore, its resolution. Since the purpose of a microscope is not solely to magnify an object but rather to resolve fine defails of the object, a higher NA objective is preferable to a low-NA objective. The NA was stated by Ernst Abbe to be related to Snell s law as follows ... 

Werner Schneider Ernst-Abbe-StraBe 3 D-93426 Roding, Germany m +49 9461 954-160 +49 9461 954-180 werner. schneider rkt. de www.rkt.de... 

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