Applications for Glass

Biotechnology, Data Storage, AR/VR, Imprint Lithography, Glass Materials


Stains, or organic residue, are discolorations on the surface due to film residue or the cleaning process.

Residual Stress

Residual or internal stress is caused by tension or index variation formed within glass during production. This can lead to striations, internal defects, and changes in the surface topography.


Particles on the surface of glass can be caused by many factors, usually during the cleaning or packaging phase. Lumina's systems are able to detect particles down to 150 nm on glass surfaces.

Inclusions and Particles

Inclusions are the result of contaminants incorporated within the glass during the melting phase.

There are two methods to detect inclusions:

  • Reflectivity: Detecting the residual stress pattern made by the inclusion
  • Dark Field: Detecting the double scattering event produced by the direct incident beam (a) and the secondary scattering event (b) due to the beam which reflects from the bottom surface of the glass

Click here for a visual representation of the method to detect inclusions


These defects can be caused either during the manufacturing phase, cleaning phase, or due to rough handling of the glass. When layers are stacked, internal scratches may occur.