I was a postdoc in the Nonlinear Photonics group at Princeton, led by Prof. Jason Fleischer. The lab works on fundamental problems in nonlinear dynamics, as well as applications in imaging. Here are a few of the projects that I have worked on:

Research

A technique inspired by Transport of Intensity (TIE) imaging, we obtain phase from a single color image using partially coherent illumination, by quantifying the color dispersion through the imaging system.

Phase from chromatic aberrations

We use TIE imaging techniques to obtain phase information from a single captured image in a Volume Holographic Microscope (VHM).

 

Quantitative phase imaging in a

Volume Holographic Microscope

We monitor 2D changes in water content of a Proton Exchange Membrane (PEM) fuel cell system in-situ in order to enable more efficient fuel cell technologies.

Two-angle phase tomography of fuel cell water content

By phase-shifting Mach-Zehnder interferometry with a rotation stage, we obtain 3D phase and amplitude distributions of complex objects and study the errors.

Complex-field tomography

We propose a method for extending the TIE technique to longer distances and multiple images by measuring and correcting for higher order nonlinearities.

Transport of Intensity imaging with

higher order derivatives

We apply a Complex Extended Kalman Filter to the problem of solving for amplitude and phase from a very noisy set of through-focus intensity images.

Complex-field imaging from noisy intensity measurements using a Kalman filter

A simple method for collecting phase-space spectrograms allows us to measure 4D distributions of both position and momentum (frequency, direction) of partially coherent (statistical) light beams, and also to create such dynamics with a spatial light modulator.

Phase-space imaging and coherence synthesis

Nonlinear dynamics has some fascinating consequences. With a nonlinear crystal to couple signal and noise beams, one can use the energy from the noise to feed the signal. I am working on computational methods for inverting the process quantitatively.

Nonlinear amplification of weak intensity signals

I did my PhD in the 3D Optical Systems Group at MIT, led by Prof. George Barbastathis, where I studied complex-field (phase and amplitude) imaging and tomography, digital holography and 3D imaging. I was a Singapore-MIT Alliance for Research and Technology (SMART) student. Here are a few of the projects that I worked on in grad school: