“Speak Flexible” was born as an expression of a 24 months national project PRIN (Progetti di Ricercadi Rilevante Interesse Nazionale – Bando 2022 PNRR), titled “Development of flexible low-voltage organic phototransistors for visible light communication (OPTICS)”
The project involves 4 national research institutions. The National Research Council (CNR), which is the leader through the SPIN Institute, participating also with other two Institutes, namely ISASI and STEMS, the National Institute of Nuclear Physics (INFN) Naples Section, the University of Naples Federico II, through the Department of Physics, and the University of Messina, with the Engineering Department.
The aim is to develop a prototype for a data transmission system (a basis for both analogue and digital data), using the visible light band. The development of a signal receiver consisting of a thin film field effect transistor, in which the active element is an organic semiconductor. Furthermore, everything will be made on a flexible substrate. Hence, the receiver will therefore consist of an organic phototransistor (OPT) grown on a sheet of polyethylene naphthalate (PEN), thinner than a normal sheet of paper. The transmitter, on the other hand, not necessarily made on flexible and/or wearable substrates, will be made up of a commercial OLED. The transmitter and receiver control electronics will be designed and developed within the project. They will have to be low noise electronics, and able to modulate the emitted signal and demodulate that of the receiving OPT.
The development of visible light communication (VLC) systems, while not new, is certainly in the spotlight. Its great advantage lies in the possibility of using a broadband completely free of licenses, not subject to electromagnetic interactions. However, there are very few VLC examples using organic transistors, and none of them have been developed in Italy. The realization of the prototype will allow the team to take a major step forward in related knowledge and technology, while also developing a demonstrator system to attract companies of the sector. Importantly, this project addresses a highly innovative field, both for the type of communication, which goes beyond conventional communication technologies, and for the use of light sensors on flexible substrates, which lend themselves to being exploited for the development of wearable electronics, another large growing market sector.
With this project we create a technological platform for the fabrication of optical devices on both flexible and wearable substrates on large area, at least 3 inch in diameter, capable of receiving, amplifying, and de-codifying signals encoded in visible light, and transferring them to other devices. The goal is to develop visible light receivers for indoor optical telecommunications, using organic. We aim at defining a link between optical sources diffused in closed environments, such as museums, hospitals, shopping centers, and wearable receiving devices, which use organic technology on flexible and wearable substrates.