Structured scintillator for digital x-ray imaging applications
Abstract
A Swedish spin-off from a University, have developed a structured scintillator for x-ray digital imaging.
This gives better resolution and improved sensitivity. It also requires lower radiation doses than today's products, while at the same time being more cost efficient. The company is interested in commercial relations with manufacturers of x-ray detector systems for different applications like medical examinations and industrial radiology.
Description
A scintillator is a material that transforms high energy radiation like x-rays into visible light. This light can then easily be detected by inexpensive devices like CCD(Charge-Coupled Device) or CMOS cameras. The thicker the scintillator plate is, the more visible light can be created. As the created light spreads while it travels through the scintillator, the thicker the scintillator plate is the less resolution is achieved.
Therefore, conventional scintillator plates always involve a trade-off between sensitivity and resolution.
A Swedish SME, which is a University spin-off, has developed and patented a scintillator matrix technology that overcomes these inherent drawbacks with conventional digital x-ray detectors.
The innovative concept channels the light on its way to the CCD camera
Deep and narrow channels are etched into silicon in order to manufacture a matrix that can be filled with a scintillator material like Thallium doped Cesium Iodide. When x-rays enter those channels, they are converted into green light, which is reflected by the channel sidewalls and therefore does not leave the channel. In this way, waveguiding properties are achieved and the scintillating photons are led to the underlying pixel without any lateral light spreading.
In this way, the structured scintillator can also be made thicker than a traditional scintillator, leading to much more efficient x-ray absorption, and thus requiring smaller radiation doses.
Excellent MTF(Modulation Transfer Function) characteristics -high resolution and contrast - has so far been measured on manufactured prototypes.
Identified key applications are
" medical x-ray imaging e.g. intra-oral sensors (dental x-ray)
" industrial radiography, e.g. Automated X-ray Inspection(AXI) and x-ray microscopy of materials.
The SME is interested in commercial agreements with manufacturers of x-ray detector systems for different applications.
The company offers the structured scintillators as "custom designed components", which enhances detector performance and reduces manufacturing costs.
The concept is protected by European and US patents.
Innovative Aspects:
While the visible light created through x-ray absorption spreads on its way through the crystal in unstructured scintillator plates, the innovative concept developed and patented by the company, channels the light on its way to the CCD camera.
This gives better resolution and improved sensitivity. It also requires lower radiation doses than today's products, while at the same time being more cost efficient.
