All optical space-to-time mapping using modal dispersion of multimode fiber

- We propose a novel method that using modal dispersion to do all optical space-to-time mapping.
- Modal dispersion of large core high numerical aperture step-index multimode fiber is investigated.
- Simulation is done to discuss the effects of mode coupling on the all optical space-to-time mapping system.
- We do experiment to demonstrate this method.

We experimentally demonstrate an all optical space-to-time mapping process using modal dispersion of large core high numerical aperture step-index multimode fiber in this paper. We use light beam with different input angle to excite various modes in a span of multimode fiber. The input optical pulses are stretched in time by modal dispersion and received by a large area, high speed photodiode. Through this process, the spatial information is directly mapped into device's temporal response. It has high speed, broad bandwidth and low system latency. Comparing with the widely used spectral imaging technology, this device is weak dependent of the input signal wavelength and optical carrier bandwidth.