OHANAThe basic feasibility

• Injecting an AO corrected image in a single-mode fiber at H or K ( hSD2)

• Coherent transport in the fiber : attenuation, dispersion, polarization, stability

• Optical path delay :

  • DC delay line : < 300 m stroke, 5-10 cm mirrors, vacuum
  • AC delay line : < 10 m stroke, < 7 cm/s, air

• Metrology & fringe tracking

  • intrinsic telescopes stability
  • atmospheric piston : < 100 um (outer scale ?)
  • classical metrological laser
  • “bright” sources : mK < 15.2 (AO + Keck Interferometer) - 3 ( estim. attenuation) = 12-13
  • “faint” sources : DSP and long blind integration or dual feed

• Beam combination, detection, visibility measurement

  • classical optics
  • integrated optics

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