Photon counting phosphorescence lifetime imaging with TimepixCam

Abstract

TimepixCam is a novel fast optical imager based on an optimized silicon pixel sensor with a thin entrance window and read out by a Timepix Application Specific Integrated Circuit. The 256 × 256 pixel sensor has a time resolution of 15 ns at a sustained frame rate of 10 Hz. We used this sensor in combination with an image intensifier for wide-field time-correlated single photon counting imaging. We have characterised the photon detection capabilities of this detector system and employed it on a wide-field epifluorescence microscope to map phosphorescence decays of various iridium complexes with lifetimes of about 1 μs in 200 μm diameter polystyrene beads.

A tunable phosphorescence supramolecular switch by an anthracene photoreaction in aqueous solution

“…In recent years, purely organic room-temperature phosphorescence (RTP) has gained increasing research interest because of its inherent advantages including a triplet state, longer lifetime and larger Stokes shift. 1–4 Therefore, RTP materials have been widely explored for potential applications in light-emitting devices, 5–7 biological imaging, 8–12 information encryption, 13–16 chemical sensing, 17–21 etc. However, purely organic molecules also have some disadvantages, such as low efficiency intersystem crossing (ISC), weak spin–orbit coupling, easy non-radiative transition, and collision quenching by oxygen or impurities, leading to hardly effective phosphorescence emission at room temperature.…”

Fast wide-field upconversion luminescence lifetime thermometry enabled by single-shot compressed ultrahigh-speed imaging

“…To accelerate data acquisition, wide-field PLI modalities based on parallel collection in time-domain and frequency-domain have been developed 36 . In the time domain, these techniques extend the TCSPC technique to wide-field imaging (e.g., TimepixCam 37 and Tpx3Cam 38 ). Photoluminescence decay over a 2D field of view (FOV) is synthesized from >100,000 frames, which requires the emission to be precisely repeatable.…”

A new imaging technology based on Compton X-ray scattering

“…On the other hand, it would enhance the spatial information by a factor of 30 relative to the SiPM matrix proposed here (the hole pitch of the acrylic hole multiplier should be reduced accordingly). Indeed, TimePix cameras are regularly used nowadays for photon-and ion-counting applications (Hirvonen et al, 2017;Fisher-Levine et al, 2018), but have not been applied to X-ray counting yet, to the best of our knowledge. The counting and signal processing algorithms could be in this way directly ported, given the similarity with the images taken in those applications.…”