X-Ray Screening

When X-rays interact with matter, they do one of three things:

• Pass through the object
• Get absorbed by the object
• Scatter from the object

Objects with higher density absorb more X-rays than objects with lesser density. Much organic material is low-density and X-rays scatter when they interact with organic objects.

Traditional transmission X-ray images like medical X-rays result when X-rays pass through an object to a detector located on the far side of the object. The resulting image is bright where most of the X-rays pass through the object and dark where most X-rays are absorbed.