Optical Surfaces Reports CFHT First Solar Light

Optical Surfaces Ltd. has reported first solar light result achievement by the SPIRou spectrograph, which is installed at the Canada-France-Hawaii Telescope (CFHT) near the summit of Mauna Kea mountain on Hawaii's Big Island.

Optical Surfaces fabricated and delivered several key optical components of the SPIRou spectrograph for the twin ZnSe prisms and the Infrasil prism, making the SPIRou triple-prism-train cross-disperser. The large Infrasil prism and the twin ZnSe prisms were manufactured to demanding specifications for transmission, wavefront error and scattered light.

The SPIRou spectrograph comprises an NIR spectropolarimeter and high-precision velocimeter optimized for both the detection of habitable Earth twins orbiting around nearby dwarf stars and the study of forming sun-like stars and their planets. SPIRou is a heritage instrument developed from the knowledge gained from previous successful spectropolarimeters (ESPaDOnS and NARVAL) and high-precision velocimeters (HARPS), consisting of a high-resolution cryogenic Echelle spectrograph fire-fed from a Cassegrainian achromatic polarimeter and calibration system. This project is managed in the framework of an international consortium led by France and involving, in addition to the CFHT, Canada, Switzerland, Brazil, Taiwan and Portugal.

"Having supplied similar optics for the successful ESPaDOnS and FEROS projects, we have a proven record in manufacturing, mounting and testing precision optics for astrophysics projects,” said Aris Kouris at Optical Surfaces. "Our congratulations go out to the SPIRou team for collecting its first nonlaboratory photons on November 15 and 16 by staring at the sun for a couple of hours. This specific experiment allowed researchers to demonstrate that SPIRou reaches a spectral resolving power of 70,000 and can measure polarimetric signatures down to sensitivities of 10 ppm. Such outstanding performance can only be achieved utilizing optical components of the highest quality.”

Optical Surfaces has provided optical components and systems for astrophysics research groups for more than 50 years. The company’s ISO 9001-2015-approved manufacturing workshops and test facilities are deep underground in a series of tunnels excavated in solid chalk where temperature remains constant and vibration is practically non-existent. With such stable conditions, testing becomes quantifiable and reliable.