How can TSA conveyor belts see through your suitcase?


I’m confused. I assume it’s a similar concept to X-Ray, but when you go through TSA line and look on their computers, there’s wireframes of everything in your bag. How?

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Traditionally the airport is using X-rays to scan your luggage, however the TSA is trying to switch over to computed tomography (commonly known as a CT scan.)

Basically they’re sending high frequency photons at your luggage, and detecting how much makes it through on the other side. Computers can use that information to develop pictures of the contents of your luggage.

It is x-ray. The way an x-ray scanner works is that they send x-rays through what is being scanned and then records how much x-rays comes out the other side. Different materials absorb x-rays at different rates. There are also different wavelengths of x-rays which gets absorbed differently. In a medical x-ray they can therefore use different settings to get images that show different things, not just bones. In the security scanners they use multiple wavelengths at once to generate a colour image.

The wireframe view is just a display option. The raw data from the security scanners look similar to the medical x-rays. However in order to get a better contrast and help the agents see shapes they convert the image to display where the density changes instead of showing the density itself. So for example a lithium ion battery is very dense and does not let through much x-rays and would appear almost completely black (or white) on the raw data. So it is hard to spot a gun on top of the battery. However when you just display the changes in density the battery shows up as just an outline. So the gun will show up as a similar outline making it much easier to spot.

It is x-ray. The computer is highlighting lines of contrasts to make it easier to see solid objects.

It’s not just similar concept, it IS x-rays. They’re x-raying the bags.

The x rays pass right through softer material and don’t pass through solid things like metal. So the TSA x ray machine can see the frame of your suitcase and the inside of your electronics the same way the doctor’s xray machine can see your bones.