1400x400_Anwendungsbereiche The gob is used for casting, or glass pressing. The moulding techniques are the dominating technology in the field of commercial lenses. For this reason, moulded lenses are built into almost any optical device, be it a CD drive, a digital or analogue camera or a headlight. Moulding glass (glass pressing) An overview of the steps of the manufacturing procedure for moulded lenses:

  1. Heat the glass in the oven
  2. The finished lens is removed from the forming tool
  3. The lenses are cooled outside of the forming tool

For glass pressing, a heated glass blank is pressed into a lens at high pressure between two moulding components (master). After the pressing procedure, the lens is cooled and can then be coated and fitted directly, i.e. without any further processing steps. The surface after the glass pressing process is similar to a polished lens, both in terms of sub-surface damage and surface finish. The blank is heated to beyond TG (glass transition temperature: temperature at which the glass becomes soft, i.e. is malleable), moulded under high pressure and pressed into its final form. External cooling allows higher cycle rates and, therefore, lower production costs. The master moulds for the glass pressing are made from very rigid materials such as silicide carbide, due to the required pressures. This occurs with the classic lens processing techniques of grinding and polishing. The glass pressing procedure is considerably less laborious than manufacturing the same optical elements from a glass block or glass rod. Another advantage of glass pressing is the diversity of shapes which a pressed optical part can take (e.g. notches, openings, edgings). These are often impossible or difficult to achieve with conventional manufacturing technology.

These lenses are used in the following fields:

  • Aspherical lenses
  • Plano-convex lenses
  • Biconvex lenses
  • Projection lenses for the automobile industry
  • LED optics Plano-convex lenses
    • Secondary lenses
    • Fresnel lens
      • Street lightin
      • Footpath lighting
      • Carpark lighting
      • Projection lenses