The inherent filtering of the collimator refers to the equivalent filtering produced by the non-removable material before the radiation beam is emitted from the radiation source assembly or its parts.
The inherent filtration of the collimator: For the X-ray tube assembly, the inherent filtration is expressed by the thickness of the reference material. Under the specified voltage and waveform, the substance makes the radiation quality expressed by the first half-valent layer consistent.
The collimator inherently filters the filtration of the X-ray machine itself, including the tube wall of the X-ray tube, the insulating oil layer, and the filter plate of the window.
The inherent filtration of the collimator is generally expressed by aluminum equivalent, that is, when a certain thickness of aluminum plate and other substances have the same amount of attenuation to X-rays, the thickness of this aluminum plate is called the aluminum equivalent of the filtered substance, and the unit is mmAl.