Structured illumination and digital lighting at the few-photon level

In recent years, advances in semiconductor based photo-detectors have led to the development of simple and compact detectors that are sufficiently sensitive to detect a single photon incident on the sensing area. These devices had revolutionary impact on instrumentation for the life sciences, and now they are starting to open up new possibilities in optical wireless communications.
At the same time, there have been significant advances in the development of light-emitting diode (LED) based lighting, which is now becoming ubiquitous.

Within the last year, the applicant and his colleagues at the University of Strathclyde have pioneered a new method of optical wireless communications that uses LEDs as transmitters and a semiconductor single photon detector as receiver. Data can be transmitted at extremely low light levels of only 30 photons/bit. Utilising a special encoding scheme, which exploits the statistical distribution of single photon detection events, such a low signal level can be maintained even under the presence of normal ambient background light. This potentially disruptive technology can be scaled to multiple LED transmitters and multiple detectors operating in parallel, opening a vast range of possible applications in imaging, communications, space communications, and robotic control.
The driving vision of the project is to realise such a highly parallel system and link it to specific applications.

During the initial development of this technology it proved crucial to interface the transmitter and receiver with configurable digital electronics to perform digital signal processing (DSP). However, these DSP interfaces do not currently have the capability required for the envisaged parallel system. The applicant and his team will investigate the challenges in integrating essential functionality, such as e.g. clock synchronisation, into the DSP hardware. Their work will enable LED displays with 100 MHz frame rate, enhanced modulation formats, and transmitter interfaces for both active- and passive-matrix LED arrays.

The project involves a broad industrial engagement strategy centred around a close link between the University of Strathclyde and Fraunhofer UK, and capitalising on two recently filed patents. Fraunhofer UK is a knowledge transfer organisation dedicated to facilitating the translation of academic research into commercial development. The University and Fraunhofer are already collaborating on other subjects and the fellowship will enable the candidate to lead the technology transfer activities in this area.
Furthermore the applicant will directly engage with the Advanced Forming Research Centre, the Scottish Centre for Excelence in Satellite Applications, and Aralia Systems, which will help to apply the technology to the specific areas of digitally controlled manufacturing, satellite communications, and surveillance systems.
The applicant will utilise his network of academic and industrial contacts in the UK to extend the application and commercialisation of the technology beyond the above mentioned areas, e.g. to ultra-low power networking units for usage in the internet of things.

The applicant and his colleagues at the University of Strathclyde pioneered a new research area of high scientific and commercial interest. The fellowship will help the team to maintain their internationally leading role and, crucially, it also ties into a strategy of technology transfer via dedicated knowledge transfer organisations, in particular Fraunhofer UK, and direct collaboration with industry.
The beneficiaries of the research within this project can be categorised into 4 groups:
1.) The worldwide scientific community
2.) UK based knowledge transfer organisations
3.) UK based companies
4.) Technology end users
Each of these groups is discussed in a dedicated section below.

1.) The worldwide scientific community:
The project explores a newly emerged area of research. The opportunities and limitations have so far only been studied in a single, confined scenario (single transmitter, single receiver, on-off keying). The project extends vastly beyond this and thus adds to the scientific knowledge, benefitting researchers worldwide.

2.) UK based knowledge transfer organisations:
Fraunhofer UK, the Scottish Centre for Excellence in Satellite Applications (SoXSA), and the Advanced Forming Research Centre are partners in the project. These organisations will take the mid-TRL technology demonstrators developed in the project into their portfolio for further development towards commercialisation. Notably, the technology is underpinning the creation of a new business centre on digital lighting within Fraunhofer UK.

3.) UK based companies:
Aralia Systems, an SME in the surveillance technologies sector, is partner in the project, and Satellite manufacturer Clyde Space is closely aligned with project partner SoXSA. The research is directly relevant to the products of these two companies and the fellow will actively collaborate with them. IP generated within the project will be available to them via licensing agreements and they can access relevant knowhow through engagement with the applicant and his team.
The technology generated in the project should also be of interest for further UK based companies PureLiFi, PhotonForce, and ST Microelectronics. Collaborative research with these companies will be undertaken as appropriate.

4.) Technology end users:
A huge variety of end users will benefit from the technology through its broad range of applications, including the internet of things (IoT), high speed and low light level imaging, and space communications. The technology has potential for ubiquitous use in IoT-connected low power units (e.g. IoT sensors or autonomous devices), thus having significant societal impact. Similarly, the technology is potentially disruptive for applications in small-satellite communications.
The technology is useful for automated surveillance systems (developed in collaboration with Aralia Systems) and has tremendous prospect for use in future security infrastructure. There is great promise for use of the technology in imaging of delicate light-sensitive samples in life sciences and in cost-efficient high-framerate imaging.