The Canada-France-Hawaii Telescope at dusk (courtesy: CFHT)

Benefiting from a unique facility, where temperatures remain constant year-round and vibration is practically non-existent, Optical Surfaces Ltd is able to routinely produce and test demanding telescope spectrograph optics (aspheres, flats, lenses, mirrors and prisms) that stretch the limits of conventional optical fabrication techniques.

Using a spectrograph, researchers are able to study the chemical and physical conditions that exist through a cross-section of space. Combined with a land or space-based telescope a spectrograph can reveal valuable information about the spectral distribution of light from a distant astronomical object.

Results from the SPIRou spectrograph at the Canada-France-Hawaii Telescope (courtesy: CFHT)

Benefitting from its highly experienced team of optical designers, engineers, and skilled production staff and its uniquely stable manufacturing facility – Optical Surfaces Ltd. has been chosen as a preferred supplier by many renowned international astronomy research groups. Notable projects completed by Optical Surfaces include SPIRou and ESPaDOnS spectrographs at the Canada-France-Hawaii telescope (CFHT), the Narval stellar spectropolarimeter on the 2m Bernard Lyot Telescope in the French Pyrenees, the High Resolution Optical Spectrograph (HROS) based on the 8m Gemini Telescope in Chile and the Fibre-fed Extended Range Optical Spectrograph (FEROS) at the European Southern Observatory (ESO).

As a leading international supplier of high precision optics for astronomical telescopes – Optical Surfaces maintains a range of interferometers that allows one-to-one testing of even the largest diameter spectrograph optics. Topographic and fringe analysis provides precise testing of surface roughness and confirms the wave front of various surface forms. Operating a rolling program for calibration of test optics where possible to national standards and production approval to ISO 9001-2015 ensures that the quality of telescope spectrograph optics from Optical Surfaces Ltd. is second to none.

For further information on high precision telescope spectrograph optics please contact Optical Surfaces Ltd. on telephone on +44-208-668-6126 / A selection of astronomical customer stories from around the world may be reviewed at