Production

Development and design

Sill Optics manufactures transmitting, rotationally symmetric glass lenses. Small batches and medium-sized series as well as prototypes are produced. In addition to a large catalog portfolio the in-house development and design department also enables customized special designs. The optical and mechanical design is constructed with the help of Zemax OpticStudio® and SolidWorks®.

Manufacturing process

The manufacturing process starts with the raw material which is supplied in the form of preforms or round disks. Various optical glasses and fused silica can be processed. The lens radii are applied during pre-grinding or milling with the help of diamond crown tools with an oversize for further manufacturing steps.  During fine grinding the lens radii are archived with a higher degree of accuracy. The lens gets transparent during polishing and finally receives its final radii which are checked with an interferometer. During centering the diameter and alignment to the optical axis are adjusted.

There are special milling tools for aspherical lenses. The MRF technology (“magneto rheological finishing”) is good for polishing aspherical lenses. This process enables a selective correction of finest deviations.

About 4 % of the light is reflected during the transition from air to glass or glass to air normally. Coatings are able to increase the transmission for certain wavelengths up to more than 99 %. In order to archive a good performance of the lens especially with high‑power lasers our special low‑absorption coatings are applied.

When all production steps have been completed the individual lenses are checked for cleanliness in the final inspection and dust‑free assembled.  A modern machine park is available for the production of the mechanical parts. The optical behavior of the finished lenses is finally tested in our laboratory before shipment. Various test facilities are available for that:

  • Interferometer
  • Wavefront sensor
  • Goniometer
  • Autocollimators
  • 3D measuring machine
  • Laser (1064 nm; 980 nm; 635 nm; 532 nm; 515 nm; 405 nm; 355 nm)

Manufacturing standards

Our lenses are specified according to the optics standard DIN EN ISO 10110. The quality standards comply with the DIN EN ISO 9001:2015.