Ben Potsaid Hot Topics presentation: MEMs tunable VCSEL technology for ultrahigh-speed OCT

In "MEMs tunable VCSEL technology for ultrahigh-speed OCT," Ben Potsaid (Massachusetts Institute of Technology) notes that optical coherence tomography (OCT) is a powerful optical technique for volumetric scanning through material like living tissue and mapping the layers of cells within that tissue. However, in order to produce an image, the laser source needs to be swept across the sample in 2D fashion and the data must be gathered at high enough speed to create an image in a reasonable time.

Potsaid discusses a swept-source technique using a MEMs tunable VCSEL (vertical cavity surface-emitting laser) which improves curent speed by a factor of 50. The MEMS element is modulated at 600kHz over a range of only 1 micron, but that is enough to sweep the wavelength of the source which provides improved sensitivity and rate of scan. Multiple scans, of areas such as a human eye retina, can now be made between heartbeats. With Doppler techniques, the flow of blood can be mapped and used for disease diagnostics.

Ben Potsaid is a Research Scientist at Thorlabs, Inc. and a Visiting Scientist at the Research Laboratory of Electronics at MIT. His research interests are in the combination of optics, motion control, and image/data processing for developing high performance systems and instrumentation for industrial, research, and biomedical applications.