Science Daily September 12, 2018
In IoT there are vast numbers of spatially distributed wireless sensors predominately based on electronics which are often are hampered by electromagnetic interference. Researchers at Washington University developed whispering gallery mode (WGM) sensors resonating at light frequencies and at vibrational or mechanical frequencies. The 127 mm by 67 mm mainboard of the WGM sensor integrates the entire architecture of the sensor system. The sensor, made of glass, is connected to the mainboard by a single optical fiber. A laser light is used to probe a WGM sensor. Light coupled out of the sensor is sent to a photodetector with a transmission amplifier. A processor controls peripherals such as the laser current drive, monitoring circuit, thermo-electric cooler and Wi-Fi unit. The research will enable IoT to exploit a new class of photonic sensors with unprecedented sensitivity and capabilities… read more. Open Access TECHNICAL ARTICLE
Architecture of the wireless WGM sensing system. Credit: Light: Science & Applications, volume 7, Article number: 62 (2018)