Optical Glass

Optical glass plays an essential role in science and industry. They can be fabricated into prisms, lenses and other optical parts to redirect or modify light beams. Glass making has a long history beginning with the traditional single-batch process or day tank method. The improved method is a continuous tank method for high volume manufacture of optical glass. The basic form of glass, an amorphous material, is a melt of silicon dioxide. The melt is cooled down in a way that it solidifies into a solid without forming a crystalline structure. Optical glass acquires its properties via their chemical composition, melting process and finishing methods. In order to obtain specific optical properties, chemical compositions must often be chosen that sometimes lead to products with less than optimum chemical resistance. These optical, chemical, and thermal properties plus others are introduced here with the most widely used optical glass, N-BK7, from SCHOTT North America, Inc. as an example.

Properties:  

• Refractive Index, Abbe Value and Dispersion Formula
• Transmittance
• Temperature Coefficient of Refractive Index (dn/dT) (Source: SCHOTT North America, Inc.)
• Glass Designations
• Thermal Properties
• Chemical properties (Source: SCHOTT North America, Inc.)
• Mechanical Properties (Source: SCHOTT North America, Inc.)
• Abbe Diagram (n_d-v_d) Graphic (Source: SCHOTT North America, Inc.)
• N-BK7 Datasheet (Source: SCHOTT North America, Inc.)