Most astronomical telescope mirror assemblies are made of glass because of its low thermal expansion coefficient with borosilicate glass. This makes very accurate optical surfaces that may vary very little with temperature, and the matching glass mirror components "track" changes in temperature and preserve the characteristics of the optical system.
The most common optical glass lens-making tool used is a Schott shoal - 7 (or equivalent from other manufacturer) and a very fine borosilicate glass crown. It is also designated as refractive index 1.517 and Abbe number 64.2 after 517642 glass. Other more expensive borosilicate glasses, such as the Schott B270 or equivalent, can be used to make "crown glass" spectacle lenses, the cost of ordinary low borosilicate glass, which is used to make kitchen utensils and even reflective telescope mirrors, not It is used to cope with the low-grade high-quality lens of this glass type by the stripe and the inclusion.
Borosilicate is also a material of choice for vacuum tube solar thermal utilization technology due to its high strength and heat resistance.
Borosilicate glass is also known as a micromechanical device known as a microelectromechanical system, and is being developed as part of the etched wafer stack for bonded borosilicate glass in the semiconductor industry.
The insulating tiles on the space shuttle are coated with borosilicate glass, and lighting equipment manufacturers use their borosilicate glass for refraction.
Its main performance indicators have reached the international ISO standards, with the United States Corning Corporation's 7740 materials, the German SCHOTT company's 50 material is the same kind of materiality. Compared with general glass, it has no toxic and side effects, its mechanical properties, thermal stability, water resistance, alkali resistance, acid resistance and other properties are greatly improved. It can be widely used in chemical, aerospace, military, family, hospitals and other fields, can be made Into a variety of products such as lamps, dishes, dials, telescopes, washing machine observation holes, microwave ovens, solar water heaters and other products, has a good promotion of value and social benefits, the emergence of this kind of glass in our country is a new revolution in the basic materials industry.
Solar water heaters, the main material of the vacuum collector tube, mainly use its good light transmission, good mechanical properties and good impact resistance. Some manufacturers use low-iron glass, the above performance is lacking, and the weight and appearance are different from the high borosilicate. (Dark, light. Generally small manufacturers use more)