Simulation study of light transport in laser-processed LYSO:Ce detectors with single-side readout.

Simulation study of light transport in laser-processed LYSO:Ce detectors with single-side readout.
Phys Med Biol. 2017 Oct 19;62(21):8419-8440
Authors: Bläckberg L, El Fakhri G, Sabet H
Abstract
A tightly focused pulsed laser beam can locally modify the crystal structure inside the bulk of a scintillator. The result is incorporation of so-called optical barriers with a refractive index different from that of the crystal bulk, that can be used to redirect the scintillation light and control the light spread in the detector. We here systematically study the scintillation light transport in detectors fabricated using the laser induced optical barrier technique, and objectively compare their potential performance characteristics with those of the two mainstream detector types: monolithic and mechanically pixelated arrays. Among countless optical barrier patterns, we explore barriers arranged in a pixel-like pattern extending all-the-way or half-way through a 20 mm thick LYSO:Ce crystal. We analyze the performance of the detectors coupled to MPPC arrays, in terms of light response functions, flood maps, line profiles, and light collection efficiency. Our results show that laser-processed detectors with both barrier patterns constitute a new detector category with a behavior between that of the two standard detector types. Results show that when the barrier-crystal interface is smooth, no DOI information can be obtained regardless of ba...

Source: Physics in Medicine and Biology - October 19, 2017 Category: Physics Authors: Bläckberg L, El Fakhri G, Sabet H Tags: Phys Med Biol Source Type: research