title: Real-time digital signal processing for live electro-optic imaging.
abstract: We present an imaging system that enables real-time magnitude and phase detection of modulated signals and its application to a Live Electro-optic Imaging (LEI) system, which realizes instantaneous visualization of RF electric fields. The real-time acquisition of magnitude and phase images of a modulated optical signal at 5 kHz is demonstrated by imaging with a Si-based high-speed CMOS image sensor and real-time signal processing with a digital signal processor. In the LEI system, RF electric fields are probed with light via an electro-optic crystal plate and downconverted to an intermediate frequency by parallel optical heterodyning, which can be detected with the image sensor. The artifacts caused by the optics and the image sensor characteristics are corrected by image processing. As examples, we demonstrate real-time visualization of electric fields from RF circuits.
authors.affiliation: National Institute of Information and Communications Technology, 4-2-1 Nukui-Kitamachi, Koganei, Tokyo 184-8795, Japan.
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Sasagawa
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kanno
authors.forename: Masahiro
authors.initials: M
authors.lastname: Tsuchiya
mesh_terms: D003199:Computer Systems; D004574:Electromagnetic Fields; D004581:Electronics / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007090:Image Interpretation, Computer-Assisted / Q000295:instrumentation*; D055617:Micro-Electrical-Mechanical Systems / Q000295:instrumentation*; D055096:Optical Devices; D015203:Reproducibility of Results; D012666:Semiconductors; D012680:Sensitivity and Specificity