  FIRST, the Fibered Imager foR a Single Telescope, is a spectro-imager using
single-mode fibers for pupil remapping, allowing measurements beyond the
telescope diffraction limit. Integrated on the Subaru Coronagraphic Extreme
Adaptive Optics instrument at the Subaru Telescope, it benefits from a very
stable visible light wavefront allowing to acquire long exposure and operate on
significantly fainter sources than previously possible. On-sky results
demonstrated the ability of the instrument to detect stellar companions
separated 43mas in the case of the Capella binary system. A similar approach on
an extremely large telescope would offer unique scientific opportunities for
companion detection and characterization at very high angular resolution.
