In the fields of industrial inspection and safety checks, as well as modern medical imaging, Flat Panel Detector (FPD) has become the core technology of digital X-ray imaging. It is gradually replacing traditional X-ray imaging methods with advantages such as high sensitivity, wide dynamic range, high-speed imaging, and low dose. Today, we will delve into the working principle, classification, application scenarios, and future development directions of FPD
Working principle and classification of PART.01FPD detector
Working principle
FPD detector is a digital X-ray flat panel detector, whose core principle is based on the characteristics of sensitive materials and digital signal processing technology.
FPD mainly consists of two parts:
X-ray sensitive layer: usually made of materials such as silicon and selenium, capable of converting X-ray energy into charge signals.
Readout circuit: responsible for collecting, amplifying, and digitizing these charge signals.
When X-rays are irradiated onto the FPD, the sensitive layer absorbs the X-rays and converts their energy into charges. These charges are collected by the readout circuit and converted into digital signals. Finally, the digital signal is processed and reconstructed to form high-quality X-ray images.
Technical characteristics of PART.02FPD detector
Application areas of PART.03 FPD detector
In the field of medical imaging, FPD detectors have become the core components of CT, DR (digital X-ray photography), DSA (digital subtraction angiography) and other equipment.
Its advantages include:
High resolution: helps doctors diagnose conditions more accurately.
Real time imaging: providing immediate support for surgery and diagnosis.
Low radiation dose: protecting patient health.
Future prospects of PART.04FPD detector
With the continuous advancement of digital technology, FPD detectors will be more widely used in the fields of medicine, industry, and safety. In the future, FPD may make breakthroughs in the following areas:
Higher resolution: meets finer detection requirements.
Faster imaging speed: Optimize signal readout and clearing mechanisms to improve dynamic photography capabilities.
Lower radiation dose: While ensuring image quality, further reducing radiation hazards.
Intelligent analysis: Combining artificial intelligence technology to achieve more efficient image analysis and defect recognition.
The reason why FPD detectors can be widely used in multiple fields is inseparable from their unique technological advantages:
High sensitivity: FPD has a higher sensitivity to X-rays than traditional film, providing clearer images.
Wide dynamic range: FPD can handle a wide range of X-ray energy and adapt to different application scenarios.
High speed imaging: Digital signal processing technology enables FPD to have fast imaging capabilities, suitable for dynamic detection.
Low dose: FPD can use lower X-ray doses under the same imaging quality, reducing radiation hazards.
Direct conversion and indirect conversion
According to the different ways in which X-rays are converted into electrical signals, FPDs can be divided into two types: direct conversion and indirect conversion.
Direct conversion flat panel detector
Core Material: Amorphous Selenium (a-Se)
Working principle: X-rays irradiate the amorphous selenium layer, exciting the generation of electron hole pairs. Under the action of an applied bias voltage, electrons and holes are separated and form a current. The current signal is stored on the inter electrode capacitance of the TFT, and then read out and converted into a digital signal.
Advantages: X-ray photons are directly converted into electrical signals without intermediate links, and have high spatial resolution. Amorphous selenium has good resolution characteristics, high sensitivity, and rich image layers. High exposure tolerance, suitable for static imaging.
Disadvantages: High environmental requirements, requiring high bias voltage. Slow refresh rate and limited dynamic photography ability.
Indirect conversion flat panel detector
Core material: CsI scintillation crystal+amorphous silicon (a-Si) photodiode
Working principle: X-rays are irradiated onto cesium iodide scintillation crystals and converted into visible light. Visible light excites amorphous silicon photodiodes, generating current and converting it into electrical signals. The electrical signal is stored and read out, ultimately generating a digital image.
Advantages: Fast imaging speed, suitable for dynamic photography. Amorphous silicon has strong radiation resistance and is suitable for multiple exposures and perspectives.
Disadvantage: Scattering and reflection may occur during the photoelectric conversion process, reducing spatial resolution.
FPD detectors, as an advanced digital X-ray imaging technology, are changing the way medical imaging, industrial testing, and safety inspections are conducted. Whether it is the high resolution of amorphous selenium or the fast imaging capability of amorphous silicon, FPD technology is constantly driving progress in related fields. In the future, with the further development of technology, FPD will play a greater role in more fields, safeguarding human health and safety.
Post time: Jun-13-2025