Friedrich Otto Schott (1851–1935) was a German chemist and expert in glassmaking. He invented borosilicate glass, a type of glass known for its strength and heat resistance. Schott carefully studied how the chemical makeup of glass affects its properties. Through his research, he solved important challenges in glassmaking, discovering compositions that achieve optical qualities close to the best possible limits. His discoveries greatly improved the quality of lenses used in microscopes and telescopes. His work is considered an important turning point in the history of glass development.

Early life and education

Schott was the son of Simon Schott, a window glass maker, and his mother was Karoline Schott. From 1870 to 1873, he studied chemical technology at the technical college in Aachen, as well as at the University of Würzburg and the University of Leipzig. He earned a doctorate in chemistry from Friedrich Schiller University of Jena, focusing on glass science. His doctoral thesis was titled “Contributions to the Theory and Practice of Glass Fabrication” (1875).

Scientific contributions

In 1879, Schott created a new type of glass that used lithium and had special optical qualities. He shared this discovery with Ernst Abbe, a physics professor at Jena University. Abbe had previously discussed problems with glass, which inspired Schott to study the subject further.

After finishing his university education, Schott learned that Abbe had described the weaknesses of the glass available at the time. These weaknesses were especially important for scientific tools like telescopes and microscopes, where the quality of glass in lenses was critical. As lenses became more powerful, they caused a problem called chromatic aberration. This problem made the quality of images depend on the color of light, which limited the usefulness of the tools.

Encouraged by Abbe’s ideas, Schott began carefully studying how glass properties changed based on its chemical makeup. He replaced some elements in the glass, such as using borate and phosphate instead of some silica, and fluoride instead of oxygen.

Schott’s 1879 letter to Abbe marked the start of a long partnership between the two scientists. At the time, Abbe was working with Carl Zeiss, an instrument maker, to create glass for microscopes. Zeiss helped test new glass compositions in real tools like telescopes. In 1882, Schott moved to Jena to work more closely with Abbe and Zeiss.

Together, they studied glass made from silica, soda, potash, lime, lead oxide, and 28 other elements. Without a clear theory to guide their work, they relied on careful observation and measurement. Adding elements that did not directly affect optical qualities could help fix other issues, like surface staining when glass was exposed to air.

By 1886, Schott had thoroughly studied how the structure of glass related to its properties. He found that the refractive index of glass (a measure of how light bends through it) could be separated from chromatic aberration. This discovery allowed him to create a lithium-based glass that performed nearly as well as possible in scientific tools, greatly improving instruments like microscopes and telescopes.

Schott mastered a process called small-scale melt-stirring, which helped him make a uniform glass with precise refractive index and dispersion measurements. Using this method, he developed many different types of glass. Based on his experiments, Schott worked with A. Winkelmann to create the first model for calculating glass properties.

Schott organized the chemical compositions of many glass types. Examples of these compositions are shown in the table.

Business interests

In 1884, Otto, along with Ernst Abbe and Carl Zeiss, started the Glastechnische Laboratorium Schott & Genossen (Schott & Associates Glass Technology Laboratory) in Jena. Between 1887 and 1893, Schott created borosilicate glass. This type of glass is known for its ability to handle high heat and sudden temperature changes without breaking. It also resists damage from harsh chemicals. This glass was first sold under the name Duran. Schott’s company also made special lenses with very little color distortion, based on his research into glass composition and properties.

Schott used borosilicate glass to make laboratory tools, medical supplies, and items like thermometers, medicine bottles, and tubes for pharmaceuticals. He also produced household glassware under the name "Jenaer Glas." Additionally, he made heat-resistant glass tubes for gas lamps. Carl Auer’s incandescent gas lamps were first sold in 1894 and became a major source of income for Schott’s business. In the late 1890s, Schott helped Jena’s industry switch to electricity. From its start until the beginning of World War I, Schott’s company had almost complete control over the global market for optical glass.

In 1919, Schott & Associates became fully owned by the Carl Zeiss Foundation. Today, the company is known as Schott AG. The Schott brand is recognized for producing high-quality and specialized optical products.

Personal life

In 1917, Otto Schott's oldest son, Rolf Schott, died during World War I. A short time later, Otto's son Erich Schott began working at Schott & Gen. In 1926, Otto Schott retired from his job at Schott & Gen. Soon after, Erich Schott took over the responsibilities of managing the company.

Awards and legacy

In 1909, Schott was awarded the Liebig Medal by the Association of German Chemists. In Jena, Germany, the street where Schott lived was renamed Otto-Schott-Straße in his honor. The Schott Glass Museum is located on the same property. Both the museum and the street can be visited. The Schott Glass Museum shows how glass science developed, starting with Otto Schott's early inventions.

Since 1991, the Otto Schott Research Award has been given every two years to scientists who make important contributions to glass science and ceramics science. The award is managed and supported by the Abbe Fund of the Carl Zeiss Foundation.