X-ray absorption is directly proportional to the density and thickness of the ray passing through the product. That is to say, the greater the product density and thickness, the more X-rays will be absorbed. For the same foreign matter, the thicker the product, the gray value contrast of the image of the foreign matter (such as metal or glass) will be reduced. Will reduce sensitivity.
The thicker the product, the more difficult it is for foreign objects to be detected, and the thinner the product, the easier it is for foreign objects to be detected.
The sensitivity of product density to detection is similar to the principle of product thickness. The smaller the product density, the greater the difference between the density of the product and the metal foreign body, the easier it is to be detected. For example, glass foreign matter is easier to detect in a low-density bread than in a dense hard cheese.