Schott N-BK 7®


Because of visible spectrum it is one of the most common glasses used to produce high-quality optics. The relatively hard borosilicate crown glass consists of purest raw materials with very few inclusions and almost completely free of bubbles.

Optical Properties

  • Excellent optical quality
  • Great Uniform transmission in the visible
  • Almost completely free of bubbles and inclusions
  • Practically colorless and clear appearance
  • High refractive index homogeneity
  • Extremely High purity of raw materials


SCHOTT® N-BK 7® is perfect for demanding optical applications and as a base material for precision optics, windows, lenses, and prisms. It provides fantastic substrates for mirror and filter coatings, measurement and sensor-technology use as well as optical lenses and dispersion prims.

Manufacture Reports and Reference

N-BK 7® Overview
N-BK 7® Data Sheet