Otto Schott

Last updated
Otto Schott
Friedrich Otto Schott.jpg
Born(1851-12-17)17 December 1851
Died27 August 1935(1935-08-27) (aged 83)
Nationality German
Alma mater Friedrich Schiller University Jena
Known forSystematic investigation of glass composition and properties
Invention of borosilicate glass
Awards Liebig Medal (1909)
Scientific career
FieldsGlass science
InstitutionsFriedrich Schiller University Jena
Schott AG

Friedrich Otto Schott (1851 - 1935) was a German chemist, glass technologist, and the inventor of borosilicate glass. Schott systematically investigated the relationship between the chemical composition of the glass and its properties. In this way, he solved fundamental problems in glass properties, identifying compositions with optical properties that approach the theoretical limit. Schott's findings were a major advance in the optics for microscopy and optical astronomy. [1] His work has been described as "a watershed in the history of glass composition". [2]


Early life and education

Schott was the son of a window glass maker, Simon Schott. His mother was Karoline Schott. [3] From 1870 to 1873 Schott studied chemical technology at the technical college in Aachen and at the University of Würzburg and at the University of Leipzig. He earned a doctorate in chemistry at Friedrich Schiller University of Jena, specializing in glass science. His doctoral thesis was entitled “Contributions to the Theory and Practice of Glass Fabrication” (1875). [4] [5] [6]

Scientific contributions

In 1879, Schott developed a new lithium-based glass that possessed novel optical properties. Schott shared this discovery with Dr Ernst Abbe, a professor of physics at Jena University whose comments on glass had stimulated Schott's interest in the subject. [2] [7]

“I recently produced a glass, in which a considerable amount of lithium was introduced, and the specific gravity of which was relatively low. I suspect that such a glass will exhibit excellent optical properties, and I therefore wanted to inquire whether you or one of your colleagues might be willing to test it for refractive index and dispersion to determine whether my above supposition is correct.” Translation of letter dated May 27, 1879. [7]

Not long after Schott had completed his formal university training, he had become aware that Abbe had articulated the deficiencies in glass that was available at the time. The deficiencies were particularly acute in scientific instruments for which optical performance of the glass in lenses such as for telescopes and microscopes. Scientifically, as the magnification power of the lenses were increased, chromatic aberration became large. Chromatic aberration causes the optical quality of the visual image to become dependent on the color of the light, resulting in a significant limitation of the scientific instrument. [1] [8]

In response to Abbe's scientific provocation, Schott began a systematic investigation of the properties of glass as the properties varied with the chemical composition. Schott substituted one element for another, such as borate and phosphate for a portion of the silica in the glass and substituting fluoride for oxygen. [2]

Schott's 1879 letter to Abbe was the beginning of a long collaboration between the two scientists. [2] Abbe was already working with Carl Zeiss, an instrument-maker, on the making of glass for microscopes. Zeiss participated in the three-way collaboration by testing improved glass compositions that Schott and Abbe identified in actual optical instruments, such as telescopes. [2] In 1882, Schott moved to Jena, where he could work more closely with Abbe and Zeiss. [2]

They created types of glass and examined their properties using silica, soda, potash, lime, lead oxide and 28 other elements. Lacking a theoretical basis for the work, they relied on careful and systematic observation and measurement. The addition of elements that had no direct effect on optical properties might help to correct other properties of a glass such as the occurrence of surface staining when exposed to air. [2]

By 1886, Schott had completed thorough investigations of structure-property relationships in glass compositions. Through these investigations, Schott discovered that the refractive index of a glass (important to its ability to function as a magnifying lens) could be disconnected from its chromatic aberration. In this way, Schott settled on a lithium-containing glass that could perform close to its theoretical limit in scientific instruments, which was a significance advance in optical instrumentation such as for microscopy and astronomy. [1]

By mastering the process of small-scale melt-stirring, Schott was able to create a homogeneous product, whose refractive index and dispersion could be exactly measured and characterized. Through systematic experiment, he applied this to the creation of an array of different glass types. Based on his experiments, Schott worked with A. Winkelmann to develop the first composition-property model for the calculation of glass properties. [2]

Glass compositions

Schott systematized the chemical composition of a significant range of glass compositions. Representative examples are summarized in the table.

Table showing examples of glass compositions identified by Otto Schott: [2]
1:1:6 soda-lime-silica glass
(reference composition, not first identified by Schott,
contains other oxides)
Jena Standard Glass67.2%2.0%14.0%7.0%0%2.5%
Schott Thermometer Glass72.0%12.0%11.0%0%0%5.0%
Schott Utensil Glass73.7%6.2%6.6%0%5.5%3.3%
Schott Welsbach Chimney Glass75.8%15.2%4.0%0%0%0%

Business interests

Schott Duran glass logo Schott duran logo.svg
Schott Duran glass logo

In 1884, in association with Dr. Ernst Abbe and Carl Zeiss, Otto founded Glastechnische Laboratorium Schott & Genossen (Schott & Associates Glass Technology Laboratory) in Jena. It was here, during the period 1887 through to 1893, that Schott developed borosilicate glass. Borosilicate glass is distinguished for its high tolerance to heat and a substantial resistance to thermal shock resulting from sudden temperature changes and resistance to degradation when exposed to corrosive chemicals. This type of glass initially became known under the brand name Duran. Their business enterprise also commercialized apochromatic lenses that had low chromatic aberration and was based on Schott's systematic investigations of the composition and properties of glass. [1] [9] [10]

Schott used borosilicate glass to make laboratory and medical supplies, including thermometers, glassware for laboratory use, medicine vials and pharmaceutical tubing. Schott produced domestic glassware under the brandname "Jenaer Glas". He also produced heat resistant lamp cylinders for use in gas lighting. Carl Auer's incandescent gas lamps were first sold in 1894 and became a lucrative source of income for Schott's glassworks. [11] In late 1890s he was also involved in the electrification of the industry in Jena. [12] Schott's business enterprise held a near monopoly on global optical glass from its inception until the start of World War I. [2]

In 1919, Schott & Associates became wholly owned by the Carl Zeiss Foundation, although Schott & Associates is known in the early 21st century as Schott AG. [13] The Schott Company's brand became associated with high quality and specialty optics. [3]

As of 2020, vials made of glass from Schott AG were being used in vaccination efforts against COVID-19 disease. [14]

Personal life

German postage stamp commemorating Otto Schott (1984) Stamps of Germany (DDR) 1984, MiNr 2848.jpg
German postage stamp commemorating Otto Schott (1984)

In 1917, Otto Schott's eldest son, Rolf Schott, was killed in World War I. Shortly thereafter, Otto's son Erich Schott joined Schott & Gen. [15] In 1926, Otto Schott retired from active work at Schott & Gen. Shortly thereafter, Erich Schott took over Otto Schott's responsibilities in managing the company. [16]

Awards and legacy

In 1909, Schott received the Liebig Medal from the Association of German Chemists. [17] Otto-Schott-Straße in Jena, Germany, the location of Schott's home, was renamed in Schott's honor. The Schott Glass Museum is on the same premises. Both can be visited. The Schott Glass Museum displays developments in glass science beginning with the innovations of Otto Schott. [18]

Since 1991, the Otto Schott Research Award has been presented every two years to meritorious researchers in the field of glass science and ceramics science. The award is organized and funded by the Abbe Fund of the Carl Zeiss Foundation. [19]

Related Research Articles

Abbe number material dispersion property

In optics and lens design, the Abbe number, also known as the V-number or constringence of a transparent material, is an approximate measure of the material's dispersion, with high values of V indicating low dispersion. It is named after Ernst Abbe (1840–1905), the German physicist who defined it. The term V-number should not be confused with the normalized frequency in fibers.

Optical aberration Deviation from perfect paraxial optical behavior

In optics, aberration is a property of optical systems, such as lenses, that causes light to be spread out over some region of space rather than focused to a point. Aberrations cause the image formed by a lens to be blurred or distorted, with the nature of the distortion depending on the type of aberration. Aberration can be defined as a departure of the performance of an optical system from the predictions of paraxial optics. In an imaging system, it occurs when light from one point of an object does not converge into a single point after transmission through the system. Aberrations occur because the simple paraxial theory is not a completely accurate model of the effect of an optical system on light, rather than due to flaws in the optical elements.

Chromatic aberration Failure of a lens to focus all colors on the same point

In optics, chromatic aberration (CA), also called chromatic distortion and spherochromatism, is a failure of a lens to focus all colors to the same point. It is caused by dispersion: the refractive index of the lens elements varies with the wavelength of light. The refractive index of most transparent materials decreases with increasing wavelength. Since the focal length of a lens depends on the refractive index, this variation in refractive index affects focusing. Chromatic aberration manifests itself as "fringes" of color along boundaries that separate dark and bright parts of the image.

Achromatic lens

An achromatic lens or achromat is a lens that is designed to limit the effects of chromatic and spherical aberration. Achromatic lenses are corrected to bring two wavelengths into focus on the same plane.

Flint glass

Flint glass is optical glass that has relatively high refractive index and low Abbe number. Flint glasses are arbitrarily defined as having an Abbe number of 50 to 55 or less. The currently known flint glasses have refractive indices ranging between 1.45 and 2.00. A concave lens of flint glass is commonly combined with a convex lens of crown glass to produce an achromatic doublet lens because of their compensating optical properties, which reduces chromatic aberration.

Carl Zeiss German optician and optical instrument maker

Carl Zeiss was a German scientific instrument maker, optician and businessman who founded the workshop of Carl Zeiss in 1846, which is still in business today as Carl Zeiss AG. Zeiss gathered a group of gifted practical and theoretical opticians and glass makers to reshape most aspects of optical instrument production. His collaboration with Ernst Abbe revolutionized optical theory and practical design of microscopes. Their quest to extend these advances brought Otto Schott into the enterprises to revolutionize optical glass manufacture. The firm of Carl Zeiss grew to one of the largest and most respected optical firms in the world.

Carl Zeiss AG German optics company

Carl Zeiss AG, branded as ZEISS, is a German manufacturer of optical systems and optoelectronics, founded in Jena, Germany in 1846 by optician Carl Zeiss. Together with Ernst Abbe and Otto Schott he laid the foundation for today's multi-national company. The current company emerged from a reunification of Carl Zeiss companies in East and West Germany with a consolidation phase in the 1990s. ZEISS is active in four business segments with approximately equal revenue, Industrial Quality and Research, Medical Technology, Consumer Markets and Semiconductor Manufacturing Technology in almost 50 countries, has 30 production sites and around 25 development sites worldwide.

Refracting telescope

A refracting telescope is a type of optical telescope that uses a lens as its objective to form an image. The refracting telescope design was originally used in spy glasses and astronomical telescopes but is also used for long focus camera lenses. Although large refracting telescopes were very popular in the second half of the 19th century, for most research purposes, the refracting telescope has been superseded by the reflecting telescope, which allows larger apertures. A refractor's magnification is calculated by dividing the focal length of the objective lens by that of the eyepiece.

Optics is the branch of physics which involves the behavior and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behavior of visible, ultraviolet, and infrared light. Because light is an electromagnetic wave, other forms of electromagnetic radiation such as X-rays, microwaves, and radio waves exhibit similar properties.

Ernst Abbe German physicist

Ernst Karl Abbe HonFRMS was a German physicist, optical scientist, entrepreneur, and social reformer. Together with Otto Schott and Carl Zeiss, he developed numerous optical instruments. He was also a co-owner of Carl Zeiss AG, a German manufacturer of scientific microscopes, astronomical telescopes, planetariums, and other advanced optical systems.

Borosilicate glass Glass made of silica and boron trioxide

Borosilicate glass is a type of glass with silica and boron trioxide as the main glass-forming constituents. Borosilicate glasses are known for having very low coefficients of thermal expansion, making them more resistant to thermal shock than any other common glass. Such glass is subjected to less thermal stress and can withstand temperature differentials without fracturing of about 165 °C (297 °F). It is commonly used for the construction of reagent bottles and flasks as well as lighting, electronics and cookware.

Schott AG German glass company

Schott AG is a German multinational glass company specializing in the manufacture of glass and glass-ceramics. Headquartered in Mainz, Germany, it is owned by the Carl Zeiss Foundation. The company's founder and namesake, Otto Schott, is credited with the invention of borosilicate glass.

Optical Museum Jena

The Deutsches Optisches Museum Jena is a science and technology museum displaying optical instruments from eight centuries. It gives a technical and cultural-historical survey of the development of optical instruments. The development of the city Jena to the centre of the optical industries since the mid-19th-century is integrated in the exhibition, connected with the lifeworks of Ernst Abbe, Carl Zeiss and Otto Schott.

Crown glass (optics) Type of glass

Crown glass is a type of optical glass used in lenses and other optical components. It has relatively low refractive index (≈1.52) and low dispersion. Crown glass is produced from alkali-lime silicates containing approximately 10% potassium oxide and is one of the earliest low dispersion glasses.

Heinrich Erfle was a German optician who spent most of his career at Carl Zeiss. In 1917 he invented the first wide-field eyepieces for telescopes and binoculars. During his short life he developed a number of new designs for telescopes and eyepieces.

Calculation of glass properties

The calculation of glass properties is used to predict glass properties of interest or glass behavior under certain conditions without experimental investigation, based on past data and experience, with the intention to save time, material, financial, and environmental resources, or to gain scientific insight. It was first practised at the end of the 19th century by A. Winkelmann and O. Schott. The combination of several glass models together with other relevant functions can be used for optimization and six sigma procedures. In the form of statistical analysis glass modeling can aid with accreditation of new data, experimental procedures, and measurement institutions.

The design of photographic lenses for use in still or cine cameras is intended to produce a lens that yields the most acceptable rendition of the subject being photographed within a range of constraints that include cost, weight and materials. For many other optical devices such as telescopes, microscopes and theodolites where the visual image is observed but often not recorded the design can often be significantly simpler than is the case in a camera where every image is captured on film or image sensor and can be subject to detailed scrutiny at a later stage. Photographic lenses also include those used in enlargers and projectors.

Low-dispersion glass is a type of glass with low dispersion. Crown glass is an example of a relatively inexpensive low-dispersion glass.

Condenser (optics) type of optical lens

A condenser is an optical lens which renders a divergent beam from a point source into a parallel or converging beam to illuminate an object.

Jena glass is a shock- and heat-resistant glass used in scientific and technological applications, especially in chemistry.


  1. 1 2 3 4 Sella, Andrea. "Schott's glass". Royal Society of Chemistry. Retrieved 20 December 2020.
  2. 1 2 3 4 5 6 7 8 9 10 Kurkjian, Charles R.; Prindle, William R. (1998). "Perspectives on the History of Glass Composition". Journal of the American Ceramics Society. 81 (4): 795–813. doi:10.1111/j.1151-2916.1998.tb02415.x.
  3. 1 2 "Founding Fathers of the Zeiss Foundation and Modern Microscopy" (PDF). Harvard University Center for Biological Imaging. Retrieved 29 December 2020.
  4. Ramirez, Ainissa (April 7, 2020). The Alchemy of Us: How Humans and Matter Transformed One Another. MIT Press. pp. 168–171. ISBN   9780262043809 . Retrieved 30 December 2020.
  5. Schott, Otto. “Contributions to the Theory and Practice of Glass Fabrication”
  6. Vogel, Werner (Dec 6, 2012). Glass Chemistry. Springer Science & Business Media. pp. 2–. ISBN   9783642787232 . Retrieved 31 December 2020.
  7. 1 2 Pfaender, H.G. (December 6, 2012). Schott Guide to Glass. Springer Science & Business Media. ISBN   9789401105170 . Retrieved 31 December 2020.
  8. Fischer, B.; Gerth, K. (1994). "Platinum for Glass Making at Jena A Reputation for Excellence was built upon early research by Döbereiner, Schott and Abbe". Platinum Metals Review. 38 (2): 74–82. Retrieved 30 December 2020.
  9. Espahangizi, Kijan (2015). "From topos to oikos: The standardization of glass containers as epistemic boundaries in modern laboratory research (1850-1900)" (PDF). Science in Context. 28 (3): 397–425. doi:10.3929/ethz-b-000103657. PMID   26256505 . Retrieved 30 December 2020.
  10. Steiner, Jürgen (1993). "Otto Schott and the Invention of Borosilicate Glass". Glastechnische Berichte. 66 (6–7): 165–173.
  11. Davidson, Michael W. "Otto Schott (1851-1935)". Molecular Expressions. The Florida State University. Retrieved 30 December 2020.
  12. Walter, Rolf (1996). Carl Zeiss: Zeiss 1905-1945 (in German). Böhlau Verlag. p. 25. ISBN   978-3-412-11096-3.
  13. Singer, Penny (August 20, 1989). "A Foundation in the Corporate Arena". New York Times.
  14. Fitzpatrick, Michelle. "German Vials in Spotlight as COVID-19 Vaccine Nears". Medical Xpress. Retrieved 2 January 2021.
  15. Cheves, Allen E.; Walker, A. Stewart (September 5, 2020). "Schott at the Sharp Edge Precision glass-ceramics influence signal strength". Lidar Magazine. Retrieved 30 December 2020.
  16. "Erich Schott (1891-1989)". Schott AG. Retrieved 29 December 2020.
  17. "Liebig-Denkmünze". (in German). 14 December 2012. Retrieved 15 September 2020.
  18. "Schott Glass Museum and Schott Villa". Magazin Retrieved 29 December 2020.
  19. "Otto Schott Research Award". Carl Zeiss Foundation. Retrieved 29 December 2020.