Alternate Scanning Technologies

Iscon uses infrared light rather than X-rays. I have no idea how well it works.

And Rapiscan has a new patent:


The present invention is directed towards an X-ray people screening system capable of rapidly screening people for detection of metals, low Z materials (plastics, ceramics and illicit drugs) and other contraband which might be concealed beneath the person’s clothing or on the person’s body. In an exemplary embodiment, the scanning system has two scanning modules that are placed in parallel, yet opposing positions relative to each other. The two modules are spaced to allow a subject, such as a person, to stand and pass between the two scanning modules. The first module and second module each include a radiation source (such as X-ray radiation) and a detector array. The subject under inspection stands between the two modules such that a front side of the subject faces one module and the back side of the subject faces the other module.

Posted on December 10, 2010 at 6:22 AM39 Comments


BF Skinner December 10, 2010 6:41 AM

“Introducing whole body imaging solutions without radiation or privacy issues. ”

So privacy and radiation ARE issues. Huh. Fancy that.

Weren’t the police enjoined from using IR camera’s to inspect houses ’cause it can show what’s going on inside? I think the case was they were looking for indoor pot farms.

Can’t imagine a clearer statement of an intent to maintain privacy in public than wearing clothes.

RobertT December 10, 2010 7:08 AM

What ever happened to all the TeraHertz molecular resonance imaging systems that were talked about a few years ago. Idea seemed ideal for explosives detection, lots of nice resonant peaks in the 200Ghz to 300Ghz range (esp TATP). Technology does not seem that difficult and should work even for cavity hidden objects.

I’m guessing this proposed IR system is tuned for detection in the 8000nm to 9000nm range, patent is not big on technical details…

atis December 10, 2010 7:08 AM

What if attacker would eat explosives in plastic containers? There have been known cases of drug trafficking in such way. Of course timing should be calculated, but for 10hour intercontinental flights that shouldn’t be much of a problem.

Shatter December 10, 2010 7:22 AM

When the whole 9/11 thing happened, I had a simple solution to prevent any and all future problems.

  1. Remove the cockpit door, seal the wall. No way to get to the cockpit form the cabin.
  2. Add a cockpit door outside the plane. Pilots enter and exit form here only.
  3. Cock pit is operated in a “depressurized state, and the pilots wear flight suits suited to such. Most are former air force, so this shouldn’t be a great shock. (optional idea)
  4. Passenger cabin is fitted with the “emergency passive system”. In the event of any problems the crew or captain can activate this.

The system is a large quantity of N2O flooded into the passenger cabin. Upon activation the Captain signal ground for an emergency landing. Response teams greet the plane with a force to deal with the problem.

Hopped up on N2O, nobody is going to care about doing anything. They will all feel funny, giggle, and enjoy the funny sounds. You can’t fight, resist, or do anything. Yes, the crew would also be affected. That’s an accept risk because of they have gas masks, they can be taken away. Everyone get’s dozes.

The effect would wear off in less than 20 seconds with normal breathing. Nobody harmed.

With the pilot door change, nobody is hijacking anything. Hostage taken? Gas the cabin. Its’ pretty simple.

However, one step better, would be to conduct REAL security at airports, and stop the useless theatrics at the gate. Profile suspects, check people as they arrive, and bring in the dogs to sniff passengers. Dogs will beat a machine 100% and actually detect explosives, which none of the new machines can do.

Clive Robinson December 10, 2010 7:49 AM

@ Shatter,

“The system is a large quantity of N2O flooded into the passenger cabin”

Minor problem N2O kills quite a few people every year.

The reason it is normaly considered safe for self administration is that you have to hold the mask on. When you get to the point of passing out you cann’t hold the mask any longer.

It’s why in maternity suites the “birthing partner” is told not to hold the mask.

Releasing sufficient quantities into the cabin to “get everyone” would almost certainly kill a number of passengers.

Thus a case for murder or manslaughter could be laid at the airlines door. And as the aircraft is most likley to land in US territory the damages could be expected to be significant for the grieving US relatives of that little grey haired granny comming over to see her new grand child and being carried by a non us carrier…

And if you think it unlikley just look at what a French Court decided the other day with respect to the Air France Concorde…

raoul December 10, 2010 7:49 AM

so.. according to the vid, facial recognition and indefinite storing of related data is not a ‘privacy issue’.

does ‘privacy’ only reach as far as one’s unmentionables?

Clive Robinson December 10, 2010 7:54 AM

@ Bruce

“uses infrared light rather than X-rays. I have Iscon uses infrared light rather than X-rays. I have no idea how well it works”

Near visable IR will go through your hand with little difficulty.

Longer wavelengths especialy if multiple wavelengths are used will quite happilly map out your major circulatory vessels in your peripheral circulatory system.

Oh and will probably be able to spot DVT’s if before and after images are available…

Charles December 10, 2010 8:14 AM

@ Clive
Do you have a citation regarding transmittance of skin/tissue over the infrared range you’re talking about? Either near IR or the “longer wavelengths” will suffice.

Scott December 10, 2010 8:24 AM

NIR and THz imaging can penetrate a very short distance into materials, but THz imaging has problems similar to holography (vibration isolation and the like).

Austringer December 10, 2010 8:26 AM

You are quite IR transparent (Google “mousepod” and you can see a neat trick someone came up with to determine where an IR fluorescent dye labeled drug / antibody / whatever ends up inside a sedated but living mouse).
If the concern is pictures of your naughty bits (and/or face) floating around, all they need to do is pick the right UV wavelength and the only image they will have is a kind of blurry indication that you have a skeleton and some major organs in there.

I give it about an hour before the “OMG! TV remote controls use an IR diode and detector! Teh terrorists could use TV remotes to determine which explosives are IR transparent. We must confiscate all the remote controls!” meme shows up on the 24 hour news channels.

Carl December 10, 2010 8:42 AM

Bruce, why are you talking about alternate scanning technologies? I thought that anything above and beyond the metal detector was an unneccessary waste of money? Passengers should be able to defend themselves, right?

Asikaa December 10, 2010 8:44 AM


Major issue with points 1 & 2. The pilots need to be able to eat, drink, use the bathroom and move around on long haul flights. Aircraft manufacturers will not add weight and cut passenger space to future designs by providing an in-cockpit bathroom.

bob December 10, 2010 8:53 AM

@Carl You seem to be implying that Bruce is inconsistent because he makes a post about something he’s not in favour of. This makes you an idiot. I hope this transient internet conversation helps in some small way toward your eventual realisation that you are not as clever as you think you are.

Charles December 10, 2010 9:02 AM

@ Austringer
The MousePOD imaging system requires an extremely controlled environment and willing subject. It is true – if you put a narrowband blackbody inside of anything, and illuminate that “thing” with monochromatic radiation, you will be able to detect the blackbody in transmission or reflection (as long as the surrounding media has relatively low attenuation).

This is unrelated to the relatively uncontrolled situation in airports.

I am still asking for a citation/reference on the transmittance of skin/tissue in the infrared frequency range. This too is unrelated to the situation currently in airports, where we merely want to image through clothing (not skin). However, I already have references on infrared transmittance of clothing. See, for example, Bjarnason et al, Applied Physics Letters, vol. 85, iss. 4, July 2004.

Leo December 10, 2010 9:12 AM

@BF Skinner: I would argue that wearing clothes is not by itself statement in favour in privacy. It’s illegal to not wear clothes.

Clive Robinson December 10, 2010 9:42 AM

@ Charles,

“I am … asking for a citation/reference on the transmittance of skin/tissue in the infrared frequency range.”

I don’t have any scientific papers that are anything like current. However both near infa red and low visable red are both used in medical equipment currently to measure the pulse and O2 saturation of blood.

As many will know from bright sunny days holding your hand up you can see low “blood” red light through your hand (you can also see the light from visable red laser pointers through your hand). Better images come from low light black and white cameras with near IR

Back in the 1980’s I was involved with work using IR (of various wave lengths) to measure blood sugar levels (not very reliable at all when still in the body).

Back in the 1980’s there was only a small amount of info from the likes of the NRPB etc. And to be honest I’ve not seen much on the medical front (either diagnostic or safety) since.

The problem was as you note humans are not that co-operative as test subjects (they like to breath etc) also there is the problem of scattering hence the reason you will need multispectral imaging.

I’ll have a dig around and see what I can find for you but I realy don’t expect much as for medical diagnostic work IR is far from ideal.

john December 10, 2010 10:13 AM

‹(O.o)› Interesting it can be more easily verified than most other claims.
Assuming the claims are testable I think we can persume it to be true. Except for the no privacy concerns. Eventualyl ridiculous airport security will cause a problem. ‹(·—·)›’ I’m of to test the [new] tor button. I’m so happy I’m a computer geek I love these goodies.

Carl December 10, 2010 10:24 AM

easy there big fella…

IF bruce is presenting this alternate scanning in a neutral/favorable light, I think it is inconsistent. The reason for that is he has attacked AIT as an unneccessary (the system is working as is w/out them) waste of money (security theatre), implemented only to enable the govt to take away our “liberties”.

I do believe that as a libertarian, bruce doesnt like the AIT scanners, feeling that they violate the 4th amendment (which is fine, everyone has a right to their opinion)
BUT, and this is the part that is iconsistent
bruce then proceeds to attack the AIT/pat down on a SECURITY basis.. “they actually worsen security, uneccessary, waste of money, security theater, etc..”

If bruce is presenting these alternate scanning methods in an “I cant believe it, look at this , more of the same!!” unfavorable light.
then he isnt being inconsistent. But that sure doesnt seem to be how he presented them..

john December 10, 2010 10:37 AM

Well actually one should count people being needlessly disgruntled and so forth it causing problems but I haven’t heard and second hand accounts of it causing problems..

Dirk Praet December 10, 2010 10:46 AM

We need more imagination and creativity here, folks. Personally, I wouldn’t mind being groped by gorgeous, mean-looking (female) officers in leather, giving me a really hard time about the contrabande I seem to be hiding in my trousers. (pun intended). Hell, I’d even pay extra for it, and I’m sure we could work out an equally fair deal for the ladies and the gay community.

Cost wise, TSA could work together with the DoJ and employ working girls/guys arrested for solliciting and sentenced to community work. With a little effort and good will, not only would US airports overnight become the most secure and hospitable in the world, chances are that the TSA would get to make money instead of the billions in tax dollars that are being squandered on questionable airport security technology and theatre today.

john December 10, 2010 11:03 AM

@Austringer I should have mentioned something like that guess that is a good point, I was thinking about such a thing.
Though I think dignity it’s more of a dignity concern than a privacy concern really.
Inspite of that… though. It does seam a better alternative to big clunky expensive machine on all sides. still interesting idea.
Simplicity is best right… so some simplification here,
1. Remove the cockpit door, seal the bullet proof bombs proof and virtually anything proof wall, further more add the bullet proof door on the outside of the vessel.*
2. Create sepperated chambers, within the airplane so that if any part of the airplane suddenly looses pressure or blows up the other parts won’t be effected.
3. Add parachutes to all the seats in the plane so if the plane does suddenly crash, the body of the plane[and the roof], will fall down to the ground in a dangerous decent[along with the blackbox which will survive] the crew will subsequently be on emergency breathing apparatus and survive.
but only 3 steps, not 4.
[laughs], on a serious note I don’t think this is necisary, adding significant weight to the vessle is prboably a bad idea. also one is unlikely to die from a terrorist attack in the first place[large ones are exceedingly rare.]
even though the hijacker is likely to be a passanger and not a pilot it is still possible for a pilot to the the hijacker or rather to say have the ideological drive to fly into a building.

john December 10, 2010 11:10 AM

@Austringer to clarify I’m still not for it.
‹(·—·)› I find this all interesting.

George December 10, 2010 11:24 AM

Irrespective of its efficacy, the viability of the infrared scanner would seem to be a function of which former (or soon-to-be-former) DHS officials stand to profit from it.

Marcos December 10, 2010 12:01 PM

Your body can be nearly transparent to IR, or completely opaque, depending on the frequency.

For any kind of material, there is an IR frquency for what it is opaque. In theory, you only need to use the frequencies of the most common explosives (including organic ones, that Xrays won’t detect) and not include the one of water. Of course, on practice things are way more complicated…

Jack December 10, 2010 12:42 PM

The plot of the Stephen King story “The Langoliers” relies on the pilot being able to lower the O2 levels in the cabin and claims that this is a know trick for calming down an unruly flight.

nobodyspecial December 10, 2010 12:56 PM

@Clive – this is a passive IR system, it relies on objects on your body have a tiny temperature difference and different emissivity.
The images penetrate your clothes just because your body heat is backlighting anything on your person.

The problem with any of these is that they rely on the operator being able to spot and identify the item. Which takes time, care and training.

It also doesn’t work (nor does the x-ray) for anything concealed by your body, either between your fingers/toes, in a fold of skin or more intimately.

Of course an alternate solution would be to publicize that the 911 attacks happened and that people should fight back against a hijacker.

No One December 10, 2010 1:25 PM

@Carl, “IF bruce is presenting this alternate scanning in a neutral/favorable light, I think it is inconsistent.”: Let’s read again exactly what Bruce himself wrote in this post: “Iscon uses infrared light rather than X-rays. I have no idea how well it works.” (The rest is a title and a copy of the abstract.)

Let’s break that down.
“Iscon uses infrared light rather than X-rays.” A neutral statement of fact. He makes no comment as to how this particular technology is different or the same.

“I have no idea how well it works.” He admits that he has no knowledge of how this measures up to x-ray scanning technology. That is, he doesn’t know whether it has the same advantages or disadvantages and thus can make no claims as to its safety, invasiveness, effect on security and so on.

This is not inconsistent; it is exactly what you would expect from a scientist who has not studied something but wants to alert others about it — a completely neutral statement including an admission of ignorance on the exact product.

Doug Coulter December 10, 2010 1:26 PM

Clive is right about the nitrous. The right amount for one person kills another, and this extends to any disabling sort of gas/drug. Believe me, as someone who once did security systems for military in a past life, the idea was seriously looked at for a number of good reasons —

False alarms no longer kill the innocent, but allow response time to determine if the trigger was innocent.

Less collateral damage — see above — the good guys wake up with a laugh, the bad guys wake up in jail.

Many wild things were proposed, from blinding flashing lights and earsplitting sound, to slippery soap bubble spray (can’t stand up, you can’t do so much harm). All had legal liability issues — there are civilians even in Army bases in places where secret stuff lives — I was one for example.

All were found wanting and put in a file on the shelf. Now this was quite awhile back, when they seemed to have a least a little bit of sense and more idea of citizen rights than now.

Jerry December 10, 2010 2:06 PM

Dirk Praet:

Oh great, now passengers are going to have to show up 4-5 hours before their flights because the lines will move so slowly.

Dirk Praet December 10, 2010 3:45 PM

@ Jerry:

Probably longer. You need to factor in a spectacular surge in male passengers, not to mention those that will give up their Saturday night at the bar to hang out at the airport instead. I am still working on the practical details to cope with this issue, but with a little help I’m sure we’ll be able to come up with something. Anyone ?

JTH December 10, 2010 4:53 PM

@BF Skinner

“Weren’t the police enjoined from using IR camera’s to inspect houses ’cause it can show what’s going on inside? I think the case was they were looking for indoor pot farms.”

Warrantless thermal imaging of a home by a law enforcement agenct is a search that violates the 4th amendment. Kyllo v. United States, 533 U.S. 27 (2001). Summary:

RobertT December 11, 2010 10:37 PM

“The images penetrate your clothes just because your body heat is backlighting anything on your person.”

In trying to IR image behind a hot object you need to overcome the dynamic range limitations of the typical optics sensor, which is mainly a problem of sensor saturation, sensor noise AND ADC quantization. The good news is that modern Analog to Digital converters are available with true 16bit performance at over 100MHZ clock speeds. Additionally most optical sensors are very linear sometimes to 6 orders of magnitude.

OK so how do you start.

1) Use Optical confocal microscopy techniques. Basically the technique adjusts the camera focal point to be behind the hot object (fore-ground) and than places a pin-hole at the optical focus point, on the image side . Everything out-of-focus gets attenuated by the ratio of the lens NA to the pin-hole diameter. This alone will fix 99% of the problems.

2) Cool the sensor with liquid Nitrogen to remove the sensor noise (look at how Hamamatsu photon counters work)

3) Use 16bit video type ADC’s for the sensors (TI and Linear Technology have commercial parts) Typical cameras only use 10bit to 12bit ADC’s so data quantization limits the ability to use digital image enhancement methods.

4) Use multiple “lines of sight” so that Tomography can be used to extract an image of the hidden object. this is simple phase array stuff..

5)Use multiple IR frequencies so the digital subtraction can be used to peel away layers by understanding the differences in transmissiblity for different fore ground objects at differing Lambdas, e.g clothing, skin….

tx December 15, 2010 3:32 PM

German ‘Fleshmob’ Protests Airport Scanners

The underwear bomber’s Christmas Day attack has prompted calls for the increased use of full-body scanners at airports that would strip-search passengers down to their naked bodies.

So to protest the use of the so-called Nacktscanner (naked scanner), members of the Pirate Party in Germany organized a “fleshmob” of people who stripped down to their skivvies last Sunday and converged on the Berlin-Tegel airport. They posted a video of their protest to YouTube, with soundtrack provided by Muse’s song “Uprising.” The lyrics articulated their protest: “They will not force us. They will stop degrading us. They will not control us. We will be victorious!”

Warning: The video above has mild nudity so may not be safe for work.

The protesters marked their bodies with a number of messages such as, “Something to hide?” and “Be a good citizen — drop your pants.”

Ripped from Wired article at:

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