Optical Imaging  


Current Research Directions:
Previous Research Directions:

We develop novel biophotonic tomographic technologies for early-cancer detection and functional imaging, using non-ionizing electromagnetic and ultrasonic waves. Unlike ionizing x-ray radiation, non-ionizing electromagnetic waves, such as optical and radio waves, pose no health hazard and at the same time reveal rich contrast mechanisms. Unfortunately, electromagnetic waves in the non-ionizing spectral region do not penetrate biological tissue in straight paths as x-rays do. Consequently, high-resolution tomography that is based on non-ionizing electromagnetic waves alone, as demonstrated by confocal microscopy, two-photon microscopy as well as optical coherence tomography, is limited to superficial imaging within about one optical transport mean free path (~1 mm) of the surface of biological tissue. Ultrasonic imaging, by comparison, provides fine image resolution but has strong speckle artifacts and has no molecular contrast. We have developed ultrasound-mediated imaging modalities by combining electromagnetic and ultrasonic waves synergistically to overcome the above problems. The hybrid modalities yield speckle-free images with high electromagnetic contrast at high ultrasonic resolution in relatively large volumes of biological tissue. Please visit the Research pages to see the specific technologies that we develop.

Last updated 2017.
Send comments, suggestions to webmaster.
Copyright 1999-2017
Caltech Optical Imaging Laboratory at the California Institute of Technology.