What is a scintillator in digital radiography?
What is a scintillator in digital radiography?
Scintillator is a material that convert radial ray such as X-ray into the visible light. By using with a light detector such as TFT, CCD, CMOS sensors, The image can be efficiently converted to a digital image.
What is scintillator layer?
Scintillators are materials that are able to convert high energy radiation such as X or gamma-rays to a near visible or visible light. The role of the photodetector is to convert the outcoming light of the scintillator to an electrical signal.
What is CsI and gos?
There are two main materials being used as scintillators in the manufacture of these detector panels: gadolinium oxysulfide (GOS) and caesium iodide scintillators (CSI). CSI detectors have the advantage of higher resolution and less x-ray dosage applied to the patients.
How does flat detector work?
Flat panel detectors FPDs are digital radiography (DR) devices that either convert x-rays into an electric charge (direct conversion) or light (indirect conversion) which is then read out through TFTs (Thin Film Transistors).
What is the material used in photodiode of flat panel scintillator?
Indirect detectors contain a layer of scintillator material, typically either gadolinium oxysulfide or cesium iodide, which converts the x-rays into light.
What makes a good scintillator?
The perfect scintillator should be dense, bright and fast. Dense means high density and high atomic number ≳ 5 g/cm3, which increases the probability of a gamma-ray interaction. The denser the scintillator, the more efficient it is at stopping gamma rays.
Which of the following is inorganic scintillator?
The most common inorganic scintillator is sodium iodide activated with a trace amount of thallium [NaI(Tl)], which has an unusually large light yield corresponding to a scintillation efficiency of about 13 percent.
How would you expect the detector efficiency to vary with the thickness of the scintillator crystal?
The thicker the crystal, the more gamma photons it can stop (and thus detect), and the more efficient a detector based on such a crystal will be.
Which scintillator has better spatial resolution?
The most significant difference seen between the two types of scintillator was for intrinsic spatial resolution, which was calculated to be 230 µm for the CsI:Tl scintillator and 1090 µm for the GOS scintillator. 0.1d+1 [28].
How does a flat panel detector work?
Varex’s X-ray flat panel detectors for digital radiography work by converting the X-rays that strike its surface into light, and then turning the light into electronic data that a computer can display as a high-quality digital image.
How many detectors does a flat panel detector?
X-rays pass through the subject being imaged and strike one of two types of detectors.
What types of Gadox scintillator screens does scintacor offer?
Scintacor offers three types of Gadox scintillator screens (sometimes referred to as luminescent screens or intensifying screens): Luminex (made of terbium-doped gadolinium oxysulphide (Gadox:Tb).
What is CSI or gadolinium oxide (Gadox)?
Cesium Iodide (CsI) or Gadolinium Oxide (GadOx)? Digital Radiography (DR) frequently uses Flat Panel Detectors (FPD). Inside these detectors is a layer of material known as a scintillator. Scintillators, which turn x-rays into light, were once referred to as “screens” when they were in film cassettes.
What is the most efficient scintillator in the world?
This phosphor, also known as P43 [7], is one of the most efficient scintillators available in terms of light output per incident X-ray energy, due to its high atomic number and density, which make it an effective absorber of X-rays.
Why does Gadox have a higher SNR than X-rays?
With less dose (lower number of x-rays) comes higher uncertainty of the recorded signal (therefore higher noise). With Gadox, the sensitivity is slightly decreased (less than 10%), but with the additional radiation dose to get the same signal, there is less noise in the signal, resulting in a slightly higher SNR.
