Limo develops glass wafer micro optics production

Tiny, large and unique worldwide – the hallmark features of the process LIMO uses to manufacture micro-optics from glass wafers. The Dortmund-based company has recently begun fabricating square wafers with a 350 mm edge length.

Dortmund-based LIMO Lissotschenko Mikrooptik GmbH has long been taking a very versatile approach to micro-optics production. The manufacturing process, which the company says is the only one of its kind in the world, is remarkable particularly because the individual optics can be as large as the entire wafer or, after they have been separated, less than 1.0 mm in size, with the individual cylindrical lenses shaped as required. This allows for a wide range of possible shapes, from aspheres right through to Fresnel lenses. Optical glass, crystals, ceramics, metals and semi-conductors (including CaF2, fused silica, ZnSe) can all serve as the raw material.

“We have been able to machine wafers up to 350 x 350 mm² since June 2014 – and to do so with utter precision”, notes Dr. Thomas Mitra, Director Development Micro Optics at LIMO. “To ensure the quality of the surfaces we use Taylor Hobson’s Form Talysurf PGI1240 surface measurement instrument, and ours is the first in the world equipped with a 300 mm feed unit.”

Especially when using telecentric masking illumination this innovation means that we can achieve very long laser lines, combine multiple laser sources into a single homogeneous illumination and equip satellites, for example, with micro-optic sensor arrays.

The new manufacturing process also enables:

  • Industrial-scale mass production of micro-optics, e.g. for laser projectors
  • Linear imaging arrays for rapid scanners used in industry (image recognition) and medical  engineering
  • Line-scanning cameras / microscopes
  • Line lamps and line illumination
  • Planar, linear wide-angle lenses
  • High-precision mechanical solutions (e.g. master plates, standard components, mechanical, abrasion-resistant spool-less deflection units, positioning units).