Related Experiment Video
Updated: Jul 25, 2025

Shaping the Amplitude and Phase of Laser Beams by Using a Phase-only Spatial Light Modulator
Published on: January 28, 2019
Topological spatial differentiation via complex amplitude filtering in Fourier space
Abstract:
Various approaches to implementing optical analog differentiation have been studied extensively and applied in edge-based image processing. Here, we report a topological optical differentiation scheme based on complex amplitude filtering, i.e., amplitude and spiral phase modulation in Fourier space. The isotropic and anisotropic multiple-order differentiation operations are demonstrated both theoretically and experimentally. Meanwhile, we also achieve multiline edge detection corresponding to the differential order for the amplitude and phase objects. This proof-of-principle work could open up new avenues for engineering a nanophotonic differentiator and realizing a more compact image-processing system.
Related Concept Videos
Properties of Fourier Transform II
The Frequency Shifting property of Fourier Transforms highlights that a shift in the frequency domain corresponds to a phase shift in the time domain. Mathematically, if x(t) has...
Properties of Fourier Transform I
In radio broadcasting, multiple audio signals often need to be transmitted simultaneously. The Fourier...
Continuous -time Fourier Transform
Properties of DTFT II
The frequency differentiation property is illustrated by considering a DTFT pair and differentiating both sides with respect to ω.
Aliasing
If the sampling frequency is below the Nyquist rate, these replicas overlap, preventing the original...
Basic signals of Fourier Transform
The sinc function, defined as sinc(x) = sin(πx)/(πx), is particularly notable for its symmetry and behavior at...

