Live Electrooptic Imaging System Based on Ultraparallel Photonic Heterodyne for Microwave Near-Fields

We report on 100 x 100 pixel live electrooptic imaging (LEI), which is real-time imaging of electrical signals on a microwave circuit. The circuit's electric near-fields can be depicted in real time on a display screen at video frame rates as high as 30 frames/s. This system is based on photonics technology in which electric near-fields are applied to an electrooptic crystal plate and a sensing light beam is modulated there. The frequency of modulation is down-converted by using a photonic heterodyne of large-scale parallelism, and the spatial pattern of the electrooptic modulation is detected with a high-speed image sensor. A digital signal processor is used to extract the frequency component of interest and to animate it on the display screen. As examples, we present live pictures of electric field pattern data acquired by the LEI system in a real-time manner.