title: Digital holography for coherent fiber beam combining with a co-propagative scheme.
abstract: We present a technique for passive coherent fiber beam combining based on digital holography. In this method, the phase errors between the fibers are compensated by the diffracted phase-conjugated -1 order of a digital hologram. Unlike previous digital holography technique, the probe beams measuring the phase errors between the fibers are co-propagating with the phase-locked signal beams. This architecture is compatible with the use of multi-stage isolated amplifying fibers. It does not require any phase calculation algorithm and its correction is collective. This concept is experimentally demonstrated with three fibers at 1.55 μm. A residual phase error of λ/20 is measured.
authors.forename: Marie
authors.initials: M
authors.lastname: Antier
authors.forename: Christian
authors.initials: C
authors.lastname: Larat
authors.forename: Eric
authors.initials: E
authors.lastname: Lallier
authors.forename: Jérôme
authors.initials: J
authors.lastname: Bourderionnet
authors.forename: Jérôme
authors.initials: J
authors.lastname: Primot
authors.forename: Arnaud
authors.initials: A
authors.lastname: Brignon
mesh_terms: D000465:Algorithms; D004867:Equipment Design; D006696:Holography / Q000295:instrumentation*; D007089:Image Enhancement; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D012815:Signal Processing, Computer-Assisted