CsI(Tl) Scintillator (CsI(Tl) Scintillation Crystal)
Cesium Iodide doped with Thallium (CsI:Tl) is a widely used inorganic scintillation crystal. Boasting a density of 4.51 g/cm³ and a light yield reaching 45% of NaI:Tl, it features an emission peak at 550 nm that matches well with silicon photodiodes. With low afterglow, excellent radiation hardness and non-cleavable structure, it serves as a key component in security screening, high-energy physics experiments and industrial non-destructive testing.
OST Photonics provides customized solutions for CsI(Tl) scintillation products, including bulk crystals, scintillation screens, as well as linear and 2D arrays, tailored to meet specific customer requirements. We also offer low-afterglow CsI(Tl) crystals with an afterglow range of 0.05% to 0.39% measured at 20ms. These specialized crystals preserve the high light yield characteristic of standard CsI(Tl) variants while drastically suppressing afterglow effects. This effectively eliminates image trailing caused by afterglow in scanning radiation imaging systems, significantly enhancing imaging clarity and resolution. As such, they are ideally suited for high-performance imaging applications demanding superior image quality and rapid scanning capabilities.
Application
Security screening: Widely used in luggage and cargo inspection systems at airports and borders due to its ability to distinguish materials via dual-energy imaging.
Medical imaging: Employed in SPECT and digital radiography systems, where high spatial resolution and low afterglow improve diagnostic accuracy.
Industrial CT: Integrated into computed tomography systems for non-destructive testing of aerospace components and electronics, benefiting from its uniformity and stability.
High-energy physics: Serves as a scintillation medium in electromagnetic calorimeters and particle detectors, valued for its radiation hardness and long-term reliability.
Features
High light yield: Reaches up to 45% of NaI:Tl, providing strong signal output for sensitive detection.
Emission peak at 550 nm: Matches ideally with silicon photodiodes and CCDs, enabling efficient light collection in compact systems.
Low afterglow: Especially in low-afterglow variants (0.05–0.39%@20ms), minimizing image trailing in fast-scanning imaging applications
High density (~4.51 g/cm³): Offers excellent stopping power for γ-rays and X-rays, enhancing detection efficiency in high-energy radiation environments.
Mechanical robustness: Non-cleavable crystal structure and low hygroscopicity make it durable and suitable for field deployment without complex encapsulation.
Production and Supply Capability
Maximum Size: ɸ120mm x 400mm
Available items: monolithic crystal, scintillation screen, linear or 2-D array
Different Types of CsI(Tl) Scintillators
Type | Relative Light Output of NaI(Tl) | Decay time | Afterglow |
Standard type | 45% | 1000 ns | 0.5~5%@6ms |
Low afterglow type | 40% | 1000 ns | 0.05~0.39%@20ms |
Properties
Relative Light Output of NaI(Tl) (%) | low afterglow type: 40; standard type: 45% |
Scintillation Decay Time (ns) | 1000 |
Emission Peak Wavelength (nm) | 550 |
Refractive Index (peak wavelength) | 1.80 |
Density（g/cm3） | 4.51 |
Hygroscopic | Slight |
Mohs hardness | 2 |
Afterglow | low afterglow type: 0.05~0.39%@20ms; standard type: 0.5~5%@6ms |
Light yield (photons/keV) | low afterglow type: 48; standard type: 54 |
