Rachel Thibout

Bio: Rachel Thibout is an academic researcher. The author has contributed to research in topics: Interferometry. The author has an hindex of 1, co-authored 1 publications receiving 3 citations.

Absolute distance measurements by laser interferometry

Abstract: A double-channel Michelson type interferometer is presented which allows absolute distance measurement up to 3 m with an uncertainty of 0.1 um. It used the principle of synthetic wavelength and can be used under vacuum or in any gaseous medium with the help of a new type of source called an air-wavelength standard. The CNES is interested in an absolute measurement both in space vacuum and on the ground, in air to characterize optical instruments.

Evolution of the MOUSE II fine longitudinal sensor towards a qualification model for PEGASE mission

Abstract: In the context of formation flying projects, one of the major points is the required precision on the intersatellites distance and/or relative displacement. According to the mission, these needs are more or less restrictive, leading to the use of fine laser metrology. Thus, for the needs of PEGASE mission – a possible DARWIN in flight demonstration- SAGEIS-CSO has been asked by CNES to design a fine longitudinal sensor able to work at 120 K while performing displacement measurements at a working distance range of 25 to 250 m. Its required performances are a resolution and a precision of 25 nm. This activity succeeds to the MOUSE II system development, which has demonstrated the ability to obtain the required laser metrology using a frequency stabilised laser, a compact and totally passive Michelson type sensor head plus a detection unit for data processing. Optical signals are routed using fibres, allowing the sensor head to be alone in a cryogenic environment. Now, the goal is to obtain a validated prototype at a MQ level by the end of 2007. For that, the laser source will be an update of the flight models made for IASI, using a more powerful DFB diode, pin-to-pin compatible with the previous design, and then giving minor changes. The current regulation was optimized in order not to degrade the narrow diode spectral width. The opto-thermo-mechanical design of the sensor head, in collaboration with AAS, is also under progress, and constitutes the major evolution of the MOUSE II.

Laser metrology: new generation of MOUSE sensors extends distance and displacement

Abstract: In the frame of the CNES R and T activity related to laser metrology, SAGEIS-CSO is actually developing a new smart interferometric sensor, last to arrive in the “MOUSE” family. In this article, we give at first a brief oversight of the MOUSE interferometric concept as well as its performances for two kinds of applications. Secondly, some interesting other set-ups for space applications are mentioned and finally we present modifications that the system will undergo in order to be compliant with long distance measurements. These different developments point out the ability of the MOUSE/IASI interferometric system to be a powerful metrological instrument for space environment.