arXiv subjects

Shachar Resisi

Publications and source records attributed to Shachar Resisi.

4 recordsLinked to original sources

arXiv2024

Tutorial: How to build and control an all-fiber wavefront modulator using mechanical perturbations

Multimode optical fibers support the dense, low-loss transmission of many spatial modes, making them attractive for technologies such as communications and imaging. However, information propagating through multimode fibers is scrambled, due to modal dispersion and mode mixing. This is usually rectified using wavefront shaping techniques with devices such as spatial light modulators. Recently, we demonstrated an all-fiber system for controlling light propagation inside multimode fibers using mechanical perturbations, called the fiber piano. In this tutorial we explain the design considerations and experimental methods needed to build a fiber piano, and review applications where fiber pianos have been used.

physics.optics↗

arXiv2022

Spectral Shaping in a Multimode Fiber by All-fiber Modulation

In the past few years, there is a renewed interest in using multimode fibers for a wide range of technologies such as communication, imaging and spectroscopy. Practical implementations of multimode fiber in such applications, however, are held back, due to the challenges in dealing with modal dispersion, mode coupling and the fiber's sensitivity to mechanical perturbations. Here, we utilize these features of multimode fibers to generate all-fiber reconfigurable spectral filters. By applying computer-controlled mechanical deformations to the fiber, along with an optimization algorithm, we manipulate the light propagation in the fiber and control its output field. Using this approach we demonstrate tunable bandpass filters and dual-band filters, with spectral resolutions as low as 5pm.

physics.optics↗

arXiv2022

Image transmission through a flexible multimode fiber by deep learning

When multimode optical fibers are perturbed, the data that is transmitted through them is scrambled. This presents a major difficulty for many possible applications, such as multimode fiber-based telecommunication and endoscopy. To overcome this challenge, a deep learning approach that generalizes over mechanical perturbations is presented. Using this approach, successful reconstruction of the input images from intensity-only measurements of speckle patterns at the output of a 1.5 meter-long randomly perturbed multimode fiber is demonstrated. The model's success is explained by hidden correlations in the speckle of random fiber conformations.

eess.IV↗

arXiv2019

Wavefront shaping in multimode fibers by transmission matrix engineering

One of the greatest challenges in utilizing multimode optical fibers is mode-mixing and inter-modal interference, which scramble the information delivered by the fiber. A common approach for canceling these effects is to tailor the optical field at the input of the fiber to obtain a desired field at its output. In this work, we present a new approach which relies on modulating the transmission matrix of the fiber rather than the incident light. We apply computer-controlled mechanical perturbations to the fiber to obtain a desired intensity pattern at its output. Using an all-fiber apparatus, we demonstrate focusing light at the distal end of the fiber and conversion between fiber modes. Since in this approach the number of degrees of control can be larger than the number of fiber modes, it allows simultaneous control over multiple inputs and multiple wavelengths.

physics.optics↗