CdWO4 Array
CdWO4 Scintillator Array for CT Imaging and Security Inspection
CdWO4 Array is a cadmium tungstate scintillator array used in industrial computed tomography, medical CT, security inspection and high-energy radiation imaging systems. CdWO4 combines high density, high atomic number, low afterglow and good radiation resistance, making it suitable for X-ray and gamma imaging applications where image lag must be controlled.
ATR Crystal supplies custom CdWO4 linear arrays and 2D pixel arrays. Common formats include 1×8, 1×16, 1×32, 1×64 linear arrays and 6×10, 12×18, 24×36 two-dimensional arrays. Pixel size, reflector material, reflector thickness, array pitch, polishing, optical coupling and housing can be reviewed according to detector design.
TiO2 and BaSO4 reflector options are available, with reflector material plus adhesive typically >=0.1 mm. The listed minimum pixel size is 0.3 mm x 1 mm, subject to array geometry, saw kerf, reflector filling and handling requirements.
Applications of CdWO4 Array
Industrial computed tomography scanners
Medical computed tomography detector modules
Security inspection for luggage, containers and vehicles
High-energy physics detector arrays
X-ray imaging and line-scan detectors
Custom linear and 2D scintillator array modules
Advantages of CdWO4 Array
- Low afterglowThe listed afterglow is <0.01% at 20 ms, useful for CT and scanning systems.
- High density and high atomic numberCdWO4 provides strong X-ray and gamma stopping power for imaging applications.
- Good radiation resistanceCdWO4 is widely used where long-term radiation exposure must be considered.
- No intrinsic radioactive backgroundCdWO4 is useful in applications where intrinsic scintillator background should be low.
- Custom pixel geometryLinear and 2D arrays can be reviewed with custom pitch, pixel size and reflector.
- Non-hygroscopic materialCdWO4 does not require hermetic sealing for moisture protection like NaI(Tl).
Specifications of CdWO4 Array
| Array Item | Typical Option | Notes |
|---|---|---|
| Linear array | 1×8, 1×16, 1×32, 1×64 and custom formats | Used for line-scan and CT detector modules. |
| 2D array | 6×10, 12×18, 24×36 and custom formats | Pixel count and pitch can be reviewed by drawing. |
| Minimum pixel size | 0.3 mm x 1 mm | Subject to geometry, reflector and processing feasibility. |
| Reflector | TiO2 or BaSO4 | Selected according to optical isolation, reflectivity and process requirement. |
Reflector Types and Thicknesses of CdWO4 Array
| Material | Thickness of Reflector Material + Adhesive |
|---|---|
| TiO2 | >=0.1 mm |
| BaSO4 | >=0.1 mm |
Properties of CdWO4 Crystal
| Property | Typical Value |
|---|---|
| Relative light output of NaI(Tl) | 30% to 50% |
| Scintillation decay time | 14000 ns |
| Emission peak wavelength | 475 nm |
| Refractive index at peak wavelength | 2.3 |
| Density | 7.9 g/cm3 |
| Hygroscopic | No |
| Mohs hardness | 4.5 |
| Afterglow | <0.01% at 20 ms |
| Cleavage plane | <010> |
| Radiation length | 1 cm |
| Light yield | 12 to 15 photons/keV |
CdWO4 Array vs. Related Scintillator Arrays
| Array Material | Main Advantage | Best Fit | Design Notes |
|---|---|---|---|
| CdWO4 | Low afterglow, high density and radiation resistance | CT, security inspection and X-ray scanning | Decay is slow, but image lag performance is useful for scanning systems. |
| BGO Array | High density and high-Z stopping power | High-energy gamma and PET-related detector arrays | Lower light yield than many scintillators. |
| CsI(Tl) Array | High light yield and good photodiode matching | X-ray imaging and detector modules | Afterglow and decay behavior should be reviewed. |
| LYSO(Ce) Array | Fast decay and high density | PET and timing-sensitive detectors | Contains lutetium intrinsic background. |
CdWO4 Array RFQ Checklist
| RFQ Item | Information to Provide |
|---|---|
| Application | Industrial CT, medical CT, security inspection, line scan, high-energy physics or custom detector. |
| Array geometry | Linear or 2D array, pixel count, pixel size, pitch, total size and drawing. |
| Reflector | TiO2, BaSO4, reflector thickness, optical isolation and cross-talk requirement. |
| Optical processing | Surface finish, polishing, coupling face, backing and sensor interface. |
| Quality target | Dimensional tolerance, light output uniformity, cross-talk, defects and inspection report. |
| Order information | Prototype quantity, batch quantity, packaging and delivery schedule. |
