Bertin Winlight contributes to the development of a number of instruments for large telescopes (VLT, ELT, Keck, Gemini, Subaru, etc.)

The increasing development of large telescopes – from a diameter of 8 meters for the Very Large Telescope (VLT) to 39 meters for the Extremely Large Telescope (ELT) – implies larger focal planes and therefore a fast-growing treasure trove of scientific information. We have come a long way from the time when astronomers observed the heavens through small, hand-held telescopes. Today’s instruments capture light and “dissect” it to analyze the characteristics of these emitted rays, providing invaluable feedback on the chemical composition of these far-off images.

For instance, we can now identify gases and other compounds making up distant stars and even galaxies. Other instruments measure speeds (of the Universe’s expansion, or of stars), allowing us to find new exoplanets. Still other experiments use spectrographs to scan the cosmos and help astrophysicists refine their models concerning dark energy and matter. For the last 20 years, Bertin Winlight has teamed up with top scientific experts to develop instruments for the world’s leading astronomy projects.

Image slicers


Bertin Winlight is the world’s leading producer of image slicers, based on a proprietary technology that was jointly developed with the French National Scientific Research Center’s Astrophysics Laboratory in Marseille (CNRS – LAM). Using this technology, we can make image slicers quickly and cost effectively, while still guaranteeing surface quality and optimized edges.

Our credentials include:

  • The Neil Gehrels Swift Observatory (SWIFT), a space telescope in service in low-Earth orbit;
  • The Keck Cosmic Web Imager (KCWI) for the M. Keck Observatory (Hawaii, U.S.)
  • The Multi Unit Spectroscopic Explorer (MUSE) for the European Southern Observatory’s (ESO) Very Large Telescope (VLT). 24 image slicers (Chile)
  • The near-infrared spectropolarimeter (SPIRou), for the Canada-France-Hawaii Telescope (Hawaii, U.S.)
  • The high-resolution solar physics network, SOLARNET


Bertin Winlight supplies complete spectrographs, as well as collimators and lenses. Applying customer specifications or operating within a consortium as partner, we bring to the table our proven expertise to design and build complete spectrograph systems (except science detectors and associated cryostats). These instruments are assembled and checked across the instrument’s entire field of view and bandwidth to ensure PSF quality and spectral dispersion characteristics.

Production spectrographs


Drawing on our long experience, we know how to produce spectrographs in volume and under tight deadlines, while also ensuring flawless quality. Our latest achievements include multi-spectrograph instruments already built or under construction for MUSE (Multi Unit Spectroscopic Explorer – 24 spectrographs), PFS (Prime Focus Spectrograph – with four spectrographs), and DESI (Dark Energy Spectroscopic Instrument10 spectrographs).

Our optical and opto-mechanical engineers contribute to the process as early as possible to guide the design for reduced cost and risks.

CollimatOrs, LENSEs, dErotatOrs

Our product line:

  • Collimators
  • Lenses (cameras)
  • Atmospheric distorsion correctors (ADC)
  • Derotators (internal reflection or with mirrors)
  • Prisms
  • Folding mirrors
  • Transport doublets
  • Field separators
  • Fore optics
    …Supplied as simple components, subsystems, or completely assembled and adjusted.
Collimators, lenses, derotators