Light falling on a photodetector produces an output current that fluctuates. The noise in this signal arises from two sources: randomness in the photon arrivals and randomness in the carrier multiplication process intrinsic to the photodetector. A general formula is derived for the variance of the photodetector output current in terms of parameters characterizing these two sources of randomness...

UNLABELLED PET and MRI are powerful imaging techniques that are largely complementary in the information they provide. We have designed and built a MR-compatible PET scanner based on avalanche photodiode technology that allows simultaneous acquisition of PET and MR images in small animals. METHODS The PET scanner insert uses magnetic field-insensitive, position-sensitive avalanche photodiode ...

The design and development of large scale, high quantum efficiency and high resolution silicon and silicon-germanium (Si/SiGe) avalanche photodiode (APD) focal plane arrays (FPAs) is an active topic of research due to the wide range of scientific, medical and industrial applications for such high sensitivity imagers. Avalanche photodiodes can attain single photon sensitive operation due the lar...

The output current of a n avalanche photodiode (APD) fluctuates in the absence of light a s well a s in its presence. The noise in this current arises from three sources: randomness in the number and in the positions at which dark carrier pairs a r e generated, randomness in the photon arrival number, and randomness in the carrier multiplication process. The volume dark current in many multilay...

An investigation is underway to determine the feasibility of planar processed, high gain, silicon avalanche photodiode arrays as a readout mechanism for scintillating fibers (SCIFI). Avalanche photodiode (APD) arrays are a compact and rugged alternative to photomultiplier tubes (PMTs). Since SCIFI usually yield a small number of photons compared with bulk scintillators, one goal of this investi...