Amur Margaryan
A Alikhanian Yerevan Institute of Physics, Armenia
Posters-Accepted Abstracts: J Med Diagn Meth
The detection of visible light underpins a wide range of scientific, engineering and applied techniques. At present, the detection of optical signals, down to the single-photon level, is carried out with Avalanche photodiodes (APD), vacuum photomultiplier tubes (PMT), or hybrid photon detectors (HPD). APD, PMT and HPD enable one to obtain precise time information about the detected photons, which is necessary in many diverse fields such as particle detection in high energy and nuclear physics, astrophysical imaging and medical imaging. The time resolution limit of current APD, PMT or HPD for single photo-electron detection is about 100 ps FWHM. It is well known that timing systems based on radio frequency (RF) fields can provide precision of the order 1 ps or better . Streak cameras, based on such principles, are used routinely for measurements in the ps time scale. Nevertheless, such RF timing techniques have so far not found wide application in fields such as elementary particle physics, nuclear physics and biomedical imaging. This is mainly related to the inability of commercially available devices to provide fast, instantaneous readout. Recently a new photon detector the radio frequency photo multiplier tube (RFPMT) was developed at Yerevan Physics Institute. Such a photomultiplier tube combines the advantages of a regular PMT or APD and the streak camera. It would be capable of detecting optical photons and providing fast (~ns) output signals, similar to a fast PMT. Event by event processing of single photons, with about 1 ps temporal resolution would be possible. The time resolution and minimal time bin for single photons detected by RFPMT is about a picosecond. The RFPMT can be operated at MHz rates and with a dedicated spiral scanning system operational rates can achieve THz over a short interval of about 100 ns, while the longer term averaged rate would be at the GHz level. The RFPMT has the potential to become a breakthrough in the single photon based timing technology. Potentially it has a number of applications in time-domain biomedical imaging devices, for example in fluorescence lifetime imaging (FLIM) microscopy, stimulated emission depletion (STED) nanoscope, diffuse optical tomography (DOT) and time-of-flight positron emission tomography (TOF-PET).
Email: mat@mail.yerphi.am
