Measurement of the index field with a pyramidal sensor

Measurement of the index field with a pyramidal sensor

Béatrice Sorrente  Vincent Michau  Bruno Fleury  Jean-Marc Conan  Jean-François Sauvage 

ONERA 29 av. de la Division Leclerc 92320 Châtillon, BP 72, France

Corresponding Author Email:;;
31 December 2017
| Citation



A pyramidal sensor specifically developed at ONERA to measure the refractive index field is presented. This sensor can be considered as a four channel schlieren. It has a robust behavior against vibrations and can realize high resolution measurements thanks to a high level of pupil sampling. Tests have been planned in a wind tunnel to evaluate its performance in presence of a turbulent flow at subsonic Mach number. From the measured phase maps, a method has been performed to determine the optical characteristics required to respect a signal to noise ratio sufficient to ensure the quality of the measured aberrations. Preliminary results and the first reconstructed phases obtained from the tests are presented in this paper. The results are compared with those obtained with a holographic interferometer


pyramidal sensor, aero-optic effects, wavefront sensor

1. Introduction
2. Principe du capteur pyramidal
3. Définition du capteur pyramidal
4. Résultats des essais en soufflerie
5. Conclusion

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