Company profile

Reosc is a world leader in the design, production and integration of high-performance optics for both civil and defense applications, including astronomy, space, high-energy lasers and the semiconductor industry. Founded in 1937 by Henri Chrétien, Reosc has developed unrivaled expertise in optics for ground-based astronomy.

Products and services by Reosc meet the most demanding requirements of a number of major research institutes and international scientific programs. Reosc designs and develops innovative astronomical instruments and develops all types of optical components (lenses, aspherical mirrors, etc.) and subassemblies, based on either customer specifications or drawings.

From concept and design to manufacture and integration, Reosc offers a complete range of high-performance optics and high-precision opto-mechanical equipment.


  • Opto-mechanical and thin-film engineering
  • Machining and lightening of glass or vitroceramic substrates
  • Precision polishing of plane, spherical, aspherical or free-form components, with a significant differentiating factor for large-size products
  • Optical metrology for surface shape and structure; accuracy to within a nanometer
  • Deposition of thin-film optical coatings adapted to high-energy laser, space, astronomy, defense and semiconductor applications
  • Assembly of high-quality opto-mechanical equipment in clean rooms


  • Large monolithic mirrors up to 8 meters in diameter
  • Segmented optics for giant telescopes
  • Thin glass sheets for adaptive optics systems
  • Active mirror assemblies, controlled by support actuators
  • Lightened structures and mirrors made of ceramic glass, silicon carbide or metal
  • High quality lenses and components
  • Customized optical thin-film coating service
  • Diffraction limited dioptric optics
  • Turnkey delivery of astronomy telescopes

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Contact us


CEO: Thierry Batut
VP Sales & Marketing: Roland Geyl

Tel: +33 (0) 1 69 89 72 00
Fax: +33 (0) 1 69 89 72 20
Address: Avenue de la Tour Maury - 91280 Saint-Pierre-du-Perray - France