A linear collimator matching linear array X - ray detector of bone density instrument
In the process of bone mineral density instrument testing, to accurately measure through human tissue and bone X ray for bone mass diagnosis, analysis of bone mineral density value, and medical diagnostics, in X-ray linear array detector front of incident X-ray collimation, makes the parallel to the collimation hole of the ray incident on the detector is then probed, belongs to the field of X-ray detection and imaging.
With the development of science and technology, X-ray has been widely used in medical imaging, industrial nondestructive testing, security and other fields. Collimator is used in conjunction with radiation detector in the field of radiation detection to constrain the direction of X-ray incident, and is an indispensable device for determining X-ray attenuation, material identification and component identification. The material of the collimator is lead or pure copper or brass or copper or tungsten or tungsten-nickel-iron.
Why are X-ray collimating materials generally pure metals with high density such as lead, copper and tungsten or alloys based on them? And tungsten alloy is the most promising of these materials. Because tungsten alloy is not harmful to human body.
Generally, The X-ray collimator is aimed at the conical X-ray produced by the X-ray machine, and the direction of X-ray emission is constrained by the collimator such as slits and holes. However, for X-ray imaging equipment such as the bone density instrument, the X-ray machine and X-ray detector are located on both sides of the detected object, and the light has a long propagation distance.Besides, X-ray diffraction may occur near the collimation slit and collimation hole, and X-ray tends to scatter to a certain extent after passing through the detected object, so the emitted X-ray is bound to be widened at the detector end. Therefore, it is necessary to configure an X-ray collimator at the front of the detector to block the scattered X-rays except the central region and improve the signal to noise ratio. The instrument is also equipped with ray blockers made of lead, pure copper, brass, copper, tungsten or tungsten-nickel-iron.
