Spatial phase information transmission through an optical fiber by coherence function synthesis

Transmission of one-dimensional spatial phase information by low-coherence light through a single-mode optical fiber is experimentally demonstrated by use of space–time conversion at a 4-f Fourier coherence function shaper and time–space conversion with spectral holography. The dispersion during the fiber propagation can be automatically compensated for with spectral holography. However, space–time coupling caused by the transmitter limits the capacity of information transmittable with one coherence function shaping. A significant advantage in the space–time–space conversion with low-coherence light is that an infinite number of signal channels can be multiplexed with a newly invented delay-time division scheme, which can extend this analog transmission to two-dimensional spatial phase patterns.