Using single-mode fibers to monitor fast Strehl ratio fluctuations

Faucherre, M.; Hubin, N.; Gitton, Philippe B.

doi:10.1051/aas:2000351

Cited by 43 publications

(23 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…First, the beams from the three telescopes are filtered by single-mode fibers to convert phase fluctuations of the corrugated wavefronts into intensity fluctuations that are monitored. The fraction of light entering the fiber is called the coupling coefficient (Shaklan & Roddier 1988) and it depends on the Strehl ratio (Coudé du Foresto et al 2000). At this point, a pair of conjugated cylindrical mirrors compresses, by a factor of about 12, the individual beams exiting from fibers into one dimensional elongated beams to be injected in the entrance slit of the spectrograph.…”

Section: Image Formationmentioning

confidence: 99%

Interferometric data reduction with AMBER/VLTI. Principle, estimators, and illustration

Tatulli

Millour

Chelli

et al. 2007

A&A

216

177

View full text Add to dashboard Cite

Aims. In this paper, we present an innovative data reduction method for single-mode interferometry. It has been specifically developed for the AMBER instrument, the three-beam combiner of the Very Large Telescope Interferometer, but it can be derived for any single-mode interferometer. Methods. The algorithm is based on a direct modelling of the fringes in the detector plane. As such, it requires a preliminary calibration of the instrument in order to obtain the calibration matrix that builds the linear relationship between the interferogram and the interferometric observable, which is the complex visibility. Once the calibration procedure has been performed, the signal processing appears to be a classical least-square determination of a linear inverse problem. From the estimated complex visibility, we derive the squared visibility, the closure phase, and the spectral differential phase. Results. The data reduction procedures have been gathered into the so-called amdlib software, now available for the community, and are presented in this paper. Furthermore, each step in this original algorithm is illustrated and discussed from various on-sky observations conducted with the VLTI, with a focus on the control of the data quality and the effective execution of the data reduction procedures. We point out the present limited performances of the instrument due to VLTI instrumental vibrations which are difficult to calibrate.

show abstract

Section: Image Formationmentioning

confidence: 99%

Interferometric data reduction with AMBER/VLTI. Principle, estimators, and illustration

Tatulli

Millour

Chelli

et al. 2007

A&A

216

177

View full text Add to dashboard Cite

show abstract

“…The coupling loss between the airy pattern at a telescope focus, and the fibre fundamental mode (Coudé du Foresto et al 2000) can be overcome. An off-axis telescope, without central obscuration, can already increase the coupling efficiency to 78%.…”

Section: Modal Transportmentioning

confidence: 99%

AGILIS: Agile Guided Interferometer for Longbaseline Imaging Synthesis

Woillez

Lai

Perrin

et al. 2017

A&A

View full text Add to dashboard Cite

Context. In comparison to the radio and sub-millimetric domains, imaging with optical interferometry is still in its infancy. Due to the limited number of telescopes in existing arrays, image generation is a demanding process that relies on time-consuming reconfiguration of the interferometer array and super-synthesis. Aims. Using single mode optical fibres for the coherent transport of light from the collecting telescopes to the focal plane, a new generation of interferometers optimized for imaging can be designed. Methods. To support this claim, we report on the successful completion of the 'OHANA Iki project: an end-to-end, on-sky demonstration of a two-telescope interferometer, built around near-infrared single mode fibres, carried out as part of the 'OHANA project. Results. Having demonstrated that coherent transport by single-mode fibres is feasible, we explore the concepts, performances, and limitations of a new imaging facility with single mode fibres at its heart: Agile Guided Interferometer for Longbaseline Imaging Synthesis (AGILIS). Conclusions. AGILIS has the potential of becoming a next generation facility or a precursor to a much larger project like the Planet Formation Imager (PFI).

show abstract

“…Mainstream astronomy has generally avoided single-mode fibers because of the difficulty of coupling light into these efficiently. Even the best performing adaptive optics systems, which attempt to deliver a diffraction-limited beam, are unable to couple light efficiently into the Gaussian-like mode of single-mode fibers below 2500 nm [3,28,29]. Consequently, astronomers have been unable to exploit numerous technological advances in photonics over the past three decades, as these have almost entirely been based on single-mode telecommunications fiber.…”

Section: Astronomy and Spectroscopymentioning

confidence: 99%

Photonic lanterns

2013

View full text Add to dashboard Cite

Multimode optical fibers have been primarily (and almost solely) used as "light pipes" in short distance telecommunications and in remote and astronomical spectroscopy. The modal properties of the multimode waveguides are rarely exploited and mostly discussed in the context of guiding light. Until recently, most photonic applications in the applied sciences have arisen from developments in telecommunications. However, the photonic lantern is one of several devices that arose to solve problems in astrophotonics and space photonics. Interestingly, these devices are now being explored for use in telecommunications and are likely to find commercial use in the next few years, particularly in the development of compact spectrographs. Photonic lanterns allow for a low-loss transformation of a multimode waveguide into a discrete number of single-mode waveguides and vice versa, thus enabling the use of single-mode photonic technologies in multimode systems. In this review, we will discuss the theory and function of the photonic lantern, along with several different variants of the technology. We will also discuss some of its applications in more detail. Furthermore, we foreshadow future applications of this technology to the field of nanophotonics.

show abstract

Using single-mode fibers to monitor fast Strehl ratio fluctuations

Cited by 43 publications

References 3 publications

Interferometric data reduction with AMBER/VLTI. Principle, estimators, and illustration

Interferometric data reduction with AMBER/VLTI. Principle, estimators, and illustration

AGILIS: Agile Guided Interferometer for Longbaseline Imaging Synthesis

Photonic lanterns

Contact Info

Product

Resources

About