Non-contact sensing system based on GaN optoelectronic chip

Abstract

As the global spread of COVID-19 becomes a rapidly evolving crisis, the development of contactless shared interactive displays is an urgent issue to reduce the risk of viral and bacterial cross contamination due to the use of touch-operated shared user terminals. Here, we experimentally demonstrate a contactless user terminal fabricated with a monolithic GaN Optoelectronic system (MGOS), which integrates the transmitter and receiver into a single chip. The inherent spectral emission-responsiveness overlap of GaN QW diodes gives the device a unique ability to detect light transmitted by diodes that share the same QW structure. When the GaN transmitter emits light to illuminate an external object, the integrated GaN receiver can detect the reflected light encoding the information and convert the optical signal into an electrical signal, so that the non-contact user terminal has the ability to use light for bidirectional data communication. Compared to traditional handwriting systems, these terminals operate as contactless information entry devices that can help reduce potential cross-contamination due to contact with handwriting terminals, provide precautions to keep the environment clean, and help prevent virus transmission.