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OPET: Optical Power Extinction Tomography

Overview Experiment Results Updates


Three-dimensional microscopy is essential in the fields of modern medicine and biology as well as high-tech manufacturing. Current techniques such as confocal microscopy and optical coherence tomography can produce three-dimensional data, but fail to produce the true reconstruction of the scattering object. Traditional diffraction tomography produces a true reconstruction of the scattered object, but requires extensive knowledge of phase and amplitude of the scattering field, which becomes more difficult as the frequency of the probe field increases. To address these deficiencies we are exploring a new tomographic imaging system based on Optical Power Extinction Tomography (OPET) that is capable of studying semi-transparent scattering objects. Our initial experiments will be limited to 2D applications and provide proof of principle that an OPET imaging system operates as theory predicts. One immediate application for the 2D system is the cross-sectional imaging of optical fibers. In the long term, we plan to build a larger and more refined instrument with full angular control of both beams. This will eventually allow for full three-dimensional reconstruction of a scattering object.

Figure 1
FIG. 1. Scheme for generating two mutually coherent beams needed to determin the data function. Two identical beams are generated at the beam splitter (BS). As shown on our Experiments page we use fibers to deliver the beams to the sample instead of the mirrors shown here.


  • P S Carney and E Wolf, "Power-extinction diffraction tomography with partially coherent light," Opt. Lett. 26, 1770-1772 (2001). PDF

  • P S Carney, E Wolf, and G S Agarwal, "Diffraction tomography using power extinction measurements," J. Opt. Soc. Am. A 16, 2643-2648 (1999). PDF

  • P S Carney, E Wolf, and G S Agarwal, "Statistical generalizations of the optical cross-section theorem with application to inverse scattering," J. Opt. Soc. Am. A 14, 3366-3371 (1997). PDF

This project is being funded by a Beckman Research Award and an Airforce MURI grant.
See theFunding page for more details

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