Detector Elements and Image Quality

The video tutorial explains the image receptor matrix, focusing on Detector Elements (DELs). DELs are small detector elements that form the digital image receptor matrix, distinct from display monitor matrices and pixels. DELs consist of a capture area, storage capacitor, and TFT gate. The capture area has three layers, and DELs work by ionizing molecules when struck by X-rays or light photons. The efficiency of DELs is linked to the size of the capture area and the fill factor, affecting contrast and spatial resolution. A larger matrix with more DELs enhances image quality. However, reducing DEL size can decrease efficiency, requiring increased beam intensity and patient dose. The solution is to reduce the pitch between DELs, allowing for higher spatial resolution.

What is the primary difference between DELs and pixels?

• DELS are used in display monitors, while pixels are used in image receptors.

• DELS are detector elements, while pixels are display elements.

• DELS and pixels are the same.

• DELS are larger than pixels.

What are the components of a DEL?

• A capture area, a storage capacitor, and a pixel.

• A capture area, a pixel, and a TFT gate.

• A capture area, a storage capacitor, and a TFT gate.

• A pixel, a storage capacitor, and a TFT gate.

What happens when X-rays or light photons strike the capture area of a DEL?

• The DEL emits light.

• The molecules in the capture area are ionized, freeing electrons.

• The DEL changes color.

• The DEL becomes inactive.

What is the role of the TFT gate in a DEL?

• It increases the DEL's fill factor.

• It stores the electrical charge.

• It releases the electrical charge when the DEL is read out.

• It captures X-rays.

What is the primary function of the storage capacitor in a DEL?

• To store the positive charge created by ionized molecules.

• To capture X-rays.

• To increase the DEL's fill factor.

• To release the electrical charge.

How does the fill factor of a DEL affect image quality?

• A higher fill factor decreases contrast resolution.

• A higher fill factor increases spatial resolution.

• A lower fill factor increases spatial resolution.

• The fill factor has no effect on image quality.

What is the relationship between the number of DELs in a matrix and the spatial resolution?

• More DELs result in lower spatial resolution.

• More DELs result in higher spatial resolution.

• The number of DELs does not affect spatial resolution.

• Fewer DELs result in higher spatial resolution.

Why can't DELs be made extremely small to fit more in a matrix?

• Because smaller DELs are more expensive.

• Because smaller DELs are harder to manufacture.

• Because smaller DELs have a reduced fill factor.

• Because smaller DELs are less durable.

What is the solution to maintaining efficiency when reducing DEL size?

• Increasing the size of the TFT gate.

• Reducing the distance between DELs, known as pitch.

• Using more powerful X-rays.

• Increasing the size of the storage capacitor.

What is the effect of a large matrix with a low pitch?

• It results in lower spatial resolution.

• It results in higher spatial resolution.

• It results in higher patient dose.

• It results in lower contrast resolution.