We report the high-frequency modulation of individual pixels in 8×8 arrays of III-nitride-based micro-pixellated light-emitting diodes, where the pixels within the array range from 14 to 84 µm in diameter. The peak emission wavelengths of the devices are 370, 405, 450 and 520 nm, respectively. Smaller area micro-LED pixels generally exhibit higher modulation bandwidths than their larger area counterparts, which is attributed to their ability to be driven at higher current densities. The highest optical -3 dB modulation bandwidths from these devices are shown to be in excess of 400 MHz, which, to our knowledge, are the highest bandwidths yet reported for GaN LEDs. These devices are also integrated with a complementary metal-oxidesemiconductor (CMOS) driver array chip, allowing for simple computer control of individual micro-LED pixels. The bandwidth of the integrated micro-LED/CMOS pixels is shown to be up to 185 MHz; data transmission at bit rates up to 512 Mbit/s is demonstrated using on-off keying non return-to-zero modulation with a bit-error ratio of less than 1×10 −10 , using a 450 nmemitting 24 µm diameter CMOS-controlled micro-LED. As the CMOS chip allows for up to 16 independent data inputs, this device demonstrates the potential for multi-Gigabit/s parallel data transmission using CMOS-controlled micro-LEDs.

A CMOS SPAD-based QVGA image sensor with 8µm pixel pitch and 26.8% fill factor is presented. The combination of analogue pixel electronics and scalable sharedwell SPAD devices facilitate high resolution, high fill-factor SPAD imaging arrays exhibiting photon shot noise limited statistics. The SPAD has 47CPS dark count rate at 1.5V excess bias (EB), 39.5% photon detection probability at 480nm and minimum 1.1ns dead time at 1V EB. Analogue single photon counting imaging is demonstrated with maximum 14.2mV/SPAD event sensitivity and 0.06e-minimum equivalent read noise. Binary Quanta Image Sensor (QIS) 16kFPS real-time oversampling is shown, verifying single photon QIS theory with 4.6x over-exposure latitude and 0.168e-read noise.

This version is available at https://strathprints.strath.ac.uk/58628/ Strathprints is designed to allow users to access the research output of the University of Strathclyde. Unless otherwise explicitly stated on the manuscript, Copyright © and Moral Rights for the papers on this site are retained by the individual authors and/or other copyright owners. Please check the manuscript for details of any other licences that may have been applied. You may not engage in further distribution of the material for any profitmaking activities or any commercial gain. You may freely distribute both the url (https://strathprints.strath.ac.uk/) and the content of this paper for research or private study, educational, or not-for-profit purposes without prior permission or charge.Any correspondence concerning this service should be sent to the Strathprints administrator: strathprints@strath.ac.ukThe Strathprints institutional repository (https://strathprints.strath.ac.uk) is a digital archive of University of Strathclyde research outputs. It has been developed to disseminate open access research outputs, expose data about those outputs, and enable the management and persistent access to Strathclyde's intellectual output.Hardware implementation algorithm and error analysis of high-speed fluorescence lifetime sensing systems using center-of-mass method Abstract. A new, simple, high-speed, and hardware-only integrationbased fluorescence-lifetime-sensing algorithm using a center-of-mass method ͑CMM͒ is proposed to implement lifetime calculations, and its signal-to-noise-ratio based on statistics theory is also deduced. Compared to the commonly used iterative least-squares method or the maximum-likelihood-estimation-based, general purpose fluorescence lifetime imaging microscopy ͑FLIM͒ analysis software, the proposed hardware lifetime calculation algorithm with CMM offers direct calculation of fluorescence lifetime based on the collected photon counts and timing information provided by in-pixel circuitry and therefore delivers faster analysis for real-time applications, such as clinical diagnosis. A real-time hardware implementation of this CMM FLIM algorithm suitable for a single-photon avalanche diode array in CMOS imaging technology is now proposed for implementation on field-programmable gate array. The performance of the proposed methods has been tested on Fluorescein, Coumarin 6, and 1,8-anilinonaphthalenesulfonate in water/methanol mixture.

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