X-ray detector---crosstalk test

There are two mechanisms for generating crosstalk. One is the crosstalk caused by the conversion of visible light converted into crystal into other photosensitive elements and the ray penetrating crystal and the barrier layer. The second is that the long-wave signal of visible light converted into crystal enters the diode and wears. Through the PN junction, carriers are excited on the substrate, and these carriers enter the PN junction of other pixels, causing crosstalk. Since the wavelength of the crystal emission is between 350 and 750 nm, the wavelength is not very long, and the crosstalk caused is small. In addition, the distance between the diode pixels is relatively large, 0.5 mm, which greatly reduces the crosstalk.

Our detector mainly solves the first crosstalk problem. There are compartments of titanium oxide and Teflon between the pixels of the crystal, which can block visible light and confine them in a single pixel, thus preventing visible light signal strings such as other pixels; collimating the rays using collimating tubes To make the ray as perpendicular to the incident as possible, and to select the appropriate crystal thickness, absorb the incident X-rays as much as possible, reduce the ray transmission (the thickness selected here is 2--4 mm), and reduce the X-rays into other images. The odds of the yuan.

In Fig. 2, the abscissa is the ten photosensitive elements of the detector, wherein the 1, 2, 3 and 4 elements are not covered with crystals, and the 5, 6, 7, 8, 9 and 10 elements are covered with crystals. The signals on the 1, 2, 3, and 4 elements are the signals of the X-rays sensed by the diodes.

If the detector has crosstalk of visible light, there will be visible light crosstalk from the fifth pixel to the surrounding pixels, at which point the signal of the fourth pixel should be larger than the signal amplitude of the first, second and third pixels. As can be seen from Figure 2, the fourth pixel is not significantly larger than the signals of the other three pixels.

If there is X-ray crosstalk in the detector, there should also be loss of X-rays from the fifth and tenth pixels to the outside of the pixel. At this time, the signals of the fifth and tenth pixels should be higher than the sixth and the The signal amplitudes of the seventh, eighth and ninth pixels are small.

If necessary, please leave your message, we will contact you as soon as possible, thank you!

Name：
Email：
Tel：
Message：