Article

An optical-fiber-scale electro-optic probe for minimally invasive high-frequency field sensing

Center for Ultrafast Optical Science, Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan 48109-2099, USA.
Optics Express (Impact Factor: 3.53). 01/2009; 16(26):21587-97. DOI: 10.1364/OE.16.021587
Source: PubMed

ABSTRACT A sub-millimeter-dimension electro-optic probe that provides enhanced scanning accessibility with significantly less intrusiveness than metal-based or even other dielectric probes during electromagnetic characterization of microwave devices is presented. The quantitative and qualitative relative invasiveness of the probe on the operation of an example antenna device-under-test is explored with respect to previously demonstrated fiber and wafer electro-optic sensors. We also demonstrate that the miniaturized probe, with a diameter of 125 microm, can be used to reconstruct the three orthogonal vector components of near-electric fields without the need for different probe crystals or multiple calibration procedures. Finally, the advantages of the reduced size and invasiveness of the new micro-scale probe are demonstrated through the enhanced resolution of detailed images extracted from planar antennas, as well as the capability of reaching into circuit locations heretofore inaccessible.

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Available from: J.F. Whitaker, Oct 16, 2014
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