title: Fast silicon photomultiplier improves signal harvesting and reduces complexity in time-domain diffuse optics.
abstract: We present a proof of concept prototype of a time-domain diffuse optics probe exploiting a fast Silicon PhotoMultiplier (SiPM), featuring a timing resolution better than 80 ps, a fast tail with just 90 ps decay time-constant and a wide active area of 1 mm2. The detector is hosted into the probe and used in direct contact with the sample under investigation, thus providing high harvesting efficiency by exploiting the whole SiPM numerical aperture and also reducing complexity by avoiding the use of cumbersome fiber bundles. Our tests also demonstrate high accuracy and linearity in retrieving the optical properties and suitable contrast and depth sensitivity for detecting localized inhomogeneities. In addition to a strong improvement in both instrumentation cost and size with respect to legacy solutions, the setup performances are comparable to those of state-of-the-art time-domain instrumentation, thus opening a new way to compact, low-cost and high-performance time-resolved devices for diffuse optical imaging and spectroscopy.
authors.forename: Alberto Dalla
authors.initials: AD
authors.lastname: Mora
authors.forename: Edoardo
authors.initials: E
authors.lastname: Martinenghi
authors.forename: Davide
authors.initials: D
authors.lastname: Contini
authors.forename: Alberto
authors.initials: A
authors.lastname: Tosi
authors.forename: Gianluca
authors.initials: G
authors.lastname: Boso
authors.forename: Turgut
authors.initials: T
authors.lastname: Durduran
authors.forename: Simon
authors.initials: S
authors.lastname: Arridge
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Martelli
authors.forename: Andrea
authors.initials: A
authors.lastname: Farina
authors.forename: Alessandro
authors.initials: A
authors.lastname: Torricelli
authors.forename: Antonio
authors.initials: A
authors.lastname: Pifferi