What is a flat panel x-ray detector?
Flat-panel detectors are a class of solid-state x-ray digital radiography devices similar in principle to the image sensors used in digital photography and video. They are used in both projectional radiography and as an alternative to x-ray image intensifiers (IIs) in fluoroscopy equipment.
What is a flat panel image detector?
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).
Which of the following is used as digital flat panel detector in digital X-ray machine?
Direct conversion flat panel detectors use a photo conductor like amorphous selenium (a-Se) or Cadmium telluride (Cd-Te) on a multi-micro electrode plate, providing the greatest sharpness and resolution. The information on both types of detectors is read by thin film transistors.
How are direct flat panel detectors constructed?
Direct flat panel detectors are based on flat panels of amorphous selenium (aSe) which is the material that the x-rays will interact and generate electron and hole pairs.
What is TFT xray?
The TFT arrays are as large as the area that is to be imaged. The function of the TFTs is to amplify the electrical signal produced by the conversion of light from the photodiodes, and to store it in the form of an electrical charge. When a high potential difference is applied to the TFT, it releases the charge.
What is the difference between computed radiography and digital radiography?
Computed radiography is an indirect process, designed to be a replacement for traditional film radiography. Digital radiography uses a digital detector array, also known as a flat panel detector in place of an IP or traditional film.
Are image intensifiers still used?
Generation 3 Thin Film technology is presently the standard for most image intensifiers used by the US military.
Are flat-panel X-ray image detectors better than X-ray film/screen cassettes?
Abstract: Advances in active-matrix array flat panels for displays over the last decade have led to the development of flat-panel X-ray image detectors. Recent flat-panel detectors have shown image quality exceeding that of X-ray film/screen cassettes.
What is a direct conversion detector and how does it work?
CdTe is a direct conversion detector and as such does not need to turn the X-ray photon into a light photon before recording it. This means the position of the conversion can be more accurately recorded and the signal is directly related to the energy of the converted photon.
What are the different approaches to flat panel detector technology?
There are two general approaches to flat panel detector technology: 1) direct and 2) indirect conversion. The present paper outlines the operating principles for direct-conversion detectors based on the use of photoconductors.
Why do we use scintillators to convert x-rays to light?
This means the position of the conversion can be more accurately recorded and the signal is directly related to the energy of the converted photon. Other radiation detectors use scintillators to convert X-rays to light.
https://www.youtube.com/watch?v=YzV1kovMjkI