Optical glasses tailor-made

Glass development and process technology

Glass production in the automated screening plant.
© Fraunhofer ISC

Glass production in the automated screening plant.

Glass in various shapes: Frit, semolina and powder.
© Fraunhofer ISC

Glass in various shapes: Frit, semolina and powder.

Polished glass rods produced by the shaft casting process.
© Fraunhofer ISC

Polished glass rods produced by the shaft casting process.

The development and manufacture of glasses and glass ceramics, in particular for optical applications, is one of the core competencies of the Glass Department of Fraunhofer ISC. Since transparent glasses with intense red tones, such as ruby or bordeaux red, cannot be produced by conventional ion staining, the glass group of the Fraunhofer ISC offers - especially for special glasses - the development and production of the desired shade of red by colloidal staining.

In addition to the red coloration, further colorations or absorption bands can be made possible by colloid and ion coloration. Furthermore, the coloration of glasses can also be achieved using colored bodies. Glasses to be used in optical applications usually have to be of high purity in order to prevent undesired absorption bands. If required, the manufacturing process can be adapted to customer-specific production systems.
 

Optical glass development

  • Lead-free glasses
  • Adaptable optical properties
  • Glass development by melt screening
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Melting technology

  • Platinum, Quartz, Iridium
  • Maximum temperature up to > 1800 °C)
  • Shape: block, bar, plate
  • Small-lot production
  •  

Optical characterization

  • Refractive index, dispersion, transmission
  • Homogeneity, stress optics, color coordinates
     

Subsequent processing

  • Redrawing to microoptical components
  • Core-shell fibers
  • Grinding, sawing, polishing
  • Non-planar geometries via cooperation partners
  • Optical joining technology
  • Low temperature joining