Array of grating-fiber couplers.
Along a single-mode fiber a number M of grating-fiber couplers are fabricated at equal spacings L(0). The fiber is coiled so that the couplers lie side by side, forming a planar optical antenna array. With varying optical frequency the resulting radiation lobes sweep slowly along the meridional direction but fast along the orthogonal azimuthal direction. In a spectrometer-type setup with M = 3 and L(0) = 300 mm a frequency resolution of 230 MHz is demonstrated.
Zürn
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Ulrich
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