Millimeter wave scanners and backscatter scanners

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Millimeter wave scanners use radio waves to reveal items concealed under clothing, while backscatter scanners utilize x-rays for detection. Backscatter technology does not penetrate the body to reveal internal organs; it primarily identifies objects beneath the skin's surface. Higher doses of x-rays are necessary for deeper penetration, but lower doses are sufficient for detecting concealed items. The key distinction lies in the detection method: backscatter measures reflected radiation, whereas traditional x-rays assess transmitted intensity. Understanding these differences is crucial for comprehending the capabilities and limitations of each scanner type.
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Millimeter wave scanners and "backscatter" scanners

I was reading about these new full body scanners that they're implementing in airports these days. The two types of scanners in use today are millimeter wave scanners and backscatter scanners. From what I've gathered, millimeter wave scanners transmit radio waves which penetrate the clothes and reflect off the body, revealing what's under the clothes.

The backscatter devices on the other hand use x-rays. Can this backscatter technology penetrate the whole body, revealing the organs and what's inside the stomach etc, similar to what a hospital x-ray machine does? I read that to get more penetrating power, a higher dose of x-rays must be used, therefore lower doses of x-rays only reveal what's under the clothes, rather than inside the body, similar to what the millimeter wave scanners are capable of. Is that correct, are higher doses of x-rays required to reveal what's under the skin?
 
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CrimpJiggler said:
Is that correct, are higher doses of x-rays required to reveal what's under the skin?
No.

https://en.wikipedia.org/wiki/Backscatter_X-ray said:
Traditional X-ray machines detect hard and soft materials by the variation in x-ray intensity transmitted through the target. In contrast, backscatter X-ray detects the radiation that reflectsfrom the target.
 
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