Kaleidoscopic Scintillation Event Imaging

2025-12-02

AI Summary

Conventional scintillator-based detection methods struggle to simultaneously achieve high spatial resolution and efficient photon collection for single-particle events, often resorting to intensity-averaged imaging or suffering from insufficient resolution. To address this, we propose a kaleidoscopic scintillator geometry—employing precisely arranged mirror surfaces to generate multiple perspective-resolved single-photon images of the same scintillation event at fixed detector positions. Integrating photon-level light transport modeling with a novel event localization inversion algorithm, our approach enables, for the first time on a commercial single-photon avalanche diode (SPAD) camera, three-dimensional sub-millimeter localization and high-resolution imaging of individual scintillation events—without requiring time-resolved hardware. This significantly improves photon utilization efficiency and preserves spatial information fidelity. All source code and experimental data are publicly available.

Technology Category

• Computer Vision: Multi-modal Vision
• Intelligent Robots: Localization, Mapping, and Navigation
• Machine Learning: Multimodal Learning

Application Category

• Security and Privacy: Data transparency and provenance
• Graph Algorithms and Modeling for the Web: Representation, reconstruction, and subgraph or motif discovery in Web-related graphs
• Search and Retrieval-Augmented AI: Retrieval-Augmented Generation (RAG) and multi-modal RAG

Abstract

Scintillators are transparent materials that interact with high-energy particles and emit visible light as a result. They are used in state of the art methods of measuring high-energy particles and radiation sources. Most existing methods use fast single-pixel detectors to detect and time scintillation events. Cameras provide spatial resolution but can only capture an average over many events, making it difficult to image the events associated with an individual particle. Emerging single-photon avalanche diode cameras combine speed and spatial resolution to enable capturing images of individual events. This allows us to use machine vision techniques to analyze events, enabling new types of detectors. The main challenge is the very low brightness of the events. Techniques have to work with a very limited number of photons. We propose a kaleidoscopic scintillator to increase light collection in a single-photon camera while preserving the event's spatial information. The kaleidoscopic geometry creates mirror reflections of the event in known locations for a given event location that are captured by the camera. We introduce theory for imaging an event in a kaleidoscopic scintillator and an algorithm to estimate the event's 3D position. We find that the kaleidoscopic scintillator design provides sufficient light collection to perform high-resolution event measurements for advanced radiation imaging techniques using a commercial CMOS single-photon camera. Code and data are available at https://github.com/bocchs/kaleidoscopic_scintillator.

Problem

• Imaging individual scintillation events with spatial resolution
• Overcoming low photon count in single-event detection
• Enabling 3D event localization using kaleidoscopic scintillator design

Innovation

• Kaleidoscopic scintillator design enhances light collection
• Algorithm estimates event's 3D position from mirror reflections
• Uses commercial CMOS single-photon camera for high-resolution imaging