PhD Candidate
California Institute of Technology
Biophotonics Laboratory

roarke (at) caltech (dot) edu

Short Biography

I am currently a graduate student in Caltech’s Electrical Engineering department. I mostly work with optics and algorithms. Please check out some of my papers in the "Research" section linked above.

Prior to coming to Caltech I was a graduate student at MIT, where I was mainly interested in 3D display technology. I also had a bit of time to help create a job recommendation algorithm, Beansprock. Please check out some press about their recent launch here and here. If you're on the lookout for a job, definitely sign up to get some great, customized suggestions.

I recently finished three papers!

The first paper in the list below is an improved algorithm to reconstruct ptychographic images (that is, compute gigapixel-scale microscope images). The second two papers are about some tricks we use to control the behavior of light, deep within tissue, to image very small things (like cells).

Solving ptychography with a convex relaxation
R. Horstmeyer, R. Y. Chen, X. Ou, B. Ames, J. A. Tropp and C. Yang, New Journal of Physics 15, 053044 (2015).

Translation correlations in anisotropically scattering media
B. Judkewitz*, R. Horstmeyer*, I. M. Vellekoop and C. Yang, Nature Physics (2015) (*shared 1st authorship, and its the cover article!)
Related news: Nature news and views

Guidestar-assisted wavefront shaping methods for focusing light into biological tissue
R. Horstmeyer, H. Ruan and C. Yang, Nature Photonics (2015)

Videos of my research

If you're more into watching clips (instead of reading academic papers), then you might like to learn more about my research through some videos.

First, I recently had the honor of giving an Everhart Lecture at Caltech. In this talk, I summarize my lab's work creating microscopes that capture gigapixel-scale images. You can find more information about this lecture here, or watch it for free at iTunes U at the link below:

Computational microscopy: turning megapixels into gigapixels

Second, I was lucky enough to feature some of my research on cryptography on the Science Channel show, Through the Wormhole, with Morgan Freeman. Check out my explanation of how one-time pads and physical unclonable functions work!

The third video you might like is a great educational tutorial on how a camera works, created by Stephanie Li Xian Seo and her team for young and curious students at If anyone else would like to animate any other optics-related subjects, please let me know!