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(Popular Science)   Have you been wondering how that thermal imaging camera was able to show the Boston bomber so clearly through the boat cover? I'm glad you asked   (popsci.com) divider line 60
    More: Interesting, thermal imaging camera, thermal imaging, Boston, shelter in place, Massachusetts State Police, cameras  
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8429 clicks; posted to Geek » on 02 May 2013 at 4:23 PM (1 year ago)   |  Favorite    |   share:  Share on Twitter share via Email Share on Facebook   more»



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2013-05-02 04:27:22 PM  
No.
 
2013-05-02 04:31:40 PM  
fun fact: spandex is transparent in the infra-red part of the spectrum.

IR filters are actually very easy to make.
 
2013-05-02 04:42:06 PM  
Clearly part of the Illumino-Nazi-Lizardman conspiracy.
 
2013-05-02 04:48:18 PM  
First of all, they say that it was the State Police, then  change their tune and say it was the boston police department in the photo caption.  Conspiracy or just shiatty journalism?  You decide.

Second, they tell us that the video was not being streamed down to the ground when we know that it was (at least the internet does).  That's just straight conspiracy right there.
 
2013-05-02 04:53:25 PM  

buttery_shame_cave: fun fact: spandex is transparent in the infra-red part of the spectrum.

IR filters are actually very easy to make.


I'm going to pretend I didn't know both of these facts.
 
2013-05-02 04:56:58 PM  
No. I know how IR works, thanks.
 
2013-05-02 04:59:47 PM  
Oh you mean ac 130 vision subby
 
M-G
2013-05-02 04:59:53 PM  
What a Safire might look like:

www.nndb.com
 
2013-05-02 05:01:13 PM  
I actually did not know that you can't use thermal imaging to look through windows. That's kinda interesting. Just hide everything in a greenhouse. BOOM, invisible.
 
2013-05-02 05:07:04 PM  

buttery_shame_cave: fun fact: spandex is transparent in the infra-red part of the spectrum.

IR filters are actually very easy to make.


Or you can just use "night vision" on your camcorder during the day to see through women's bathing suits, I mean search for illegal weapons.
 
2013-05-02 05:07:18 PM  
PopSci's comment section reminds me why I don't read PopSci anymore.
 
2013-05-02 05:13:42 PM  
Well it's pretty much like that sniper scope in Navy Seals with Charlie Sheen that sees body heat through 2 feet of concrete, right?
 
2013-05-02 05:19:54 PM  

jigger: buttery_shame_cave: fun fact: spandex is transparent in the infra-red part of the spectrum.

IR filters are actually very easy to make.

Or you can just use "night vision" on your camcorder during the day to see through women's bathing suits, I mean search for illegal weapons.


"Camcorder"...how quaint.  I remember those!
 
2013-05-02 05:28:49 PM  

Car_Ramrod: I actually did not know that you can't use thermal imaging to look through windows. That's kinda interesting. Just hide everything in a greenhouse. BOOM, invisible.


Two major considerations for IR are emissivity and reflectivity.  Glass, Plexi, Shiny metals, etc have high reflectivity and show the heat from things around it, but not through it.  Emissivity his how well something shows (emits) heat.  Dark colors emit heat better than light colors.

Certified Thermographer w/ $65K FLIR camera at work.
 
2013-05-02 05:29:06 PM  
Yet, Iraqis figured out how to disguise their foxholes from FLIR in gulf war 2 by using heavy blankets. It all depends on the material.

My first instinct, if I needed a lightweight material to block FLIR, would be to find something like mylar--coated in aluminum or gold on one side, it should be fairly reflective all across the near-visual part of the spectrum. Failing that? IDK. Polartec fleece? Stuff does a pretty good job of keeping body heat in, though it might be too porous. Apparently common plastic tarps are right out, as the article shows. Could drenching yourself in cold water reduce your heat signature to background levels? Maybe mud, Predator style?

These "eye of god" technologies are pretty damn scary.
 
2013-05-02 05:31:06 PM  

Calehedron: Car_Ramrod: I actually did not know that you can't use thermal imaging to look through windows. That's kinda interesting. Just hide everything in a greenhouse. BOOM, invisible.

Two major considerations for IR are emissivity and reflectivity.  Glass, Plexi, Shiny metals, etc have high reflectivity and show the heat from things around it, but not through it.  Emissivity his how well something shows (emits) heat.  Dark colors emit heat better than light colors.

Certified Thermographer w/ $65K FLIR camera at work.


So why is it still called forward looking if they're mounted in a way that lets you point it wherever you like?
 
2013-05-02 05:40:37 PM  

Russ1642: So why is it still called forward looking if they're mounted in a way that lets you point it wherever you like?


Conspiracy theory #1: Back in the day, while the equipment was heavier and rigidly mounted to the helicopter, it looked looked downward. Then someone developed a system that was mounted so that it looked forward, maybe looking for missiles and other threats in the flight path. Pilots were greatly impressed by the system, which they came to know as FLIR (forward-looking infrared). Marketers, knowing this, kept on using the acronym to sell product long after it no longer made any sense.
 
2013-05-02 05:40:51 PM  
Sounds like a good reason to buy a Drone. One of those could have been very handy to have loitering over an area or even going through a search pattern looking for good ol' Johar. He was plenty hot in the IR lying in that cold boat with just a light hoody and jeans. I bet he felt like he was freezing though. He had been out in the weather for over 10 hours at that point.
 
2013-05-02 05:40:58 PM  

buttery_shame_cave: fun fact: spandex is transparent in the infra-red part of the spectrum.

IR filters are actually very easy to make.


Yes, but not with the same results seen in a FLIR system. Filtering out all wavelengths outside FLIR doesn't modify the intended wavelengths and intensities to record by your camera.

Cthulhu_is_my_homeboy: Yet, Iraqis figured out how to disguise their foxholes from FLIR in gulf war 2 by using heavy blankets. It all depends on the material.

My first instinct, if I needed a lightweight material to block FLIR, would be to find something like mylar--coated in aluminum or gold on one side, it should be fairly reflective all across the near-visual part of the spectrum. Failing that? IDK. Polartec fleece? Stuff does a pretty good job of keeping body heat in, though it might be too porous. Apparently common plastic tarps are right out, as the article shows. Could drenching yourself in cold water reduce your heat signature to background levels? Maybe mud, Predator style?

These "eye of god" technologies are pretty damn scary.


The trick is to use something that won't look out of place. Windows are expected to be where they are. A cold-spashed person would still be pretty obvious b/c the background pattern will be disrupted, and there's no way to cover yourself evenly. Fox hole blankets mostly likely worked because they were not being directly heated by those beneath them, and they would reach ambient temperature and generally stay there.
 
2013-05-02 05:44:52 PM  

Russ1642: Calehedron: Car_Ramrod: I actually did not know that you can't use thermal imaging to look through windows. That's kinda interesting. Just hide everything in a greenhouse. BOOM, invisible.

Two major considerations for IR are emissivity and reflectivity.  Glass, Plexi, Shiny metals, etc have high reflectivity and show the heat from things around it, but not through it.  Emissivity his how well something shows (emits) heat.  Dark colors emit heat better than light colors.

Certified Thermographer w/ $65K FLIR camera at work.

So why is it still called forward looking if they're mounted in a way that lets you point it wherever you like?


FLIR is the company name that developed some of the first IR products back in the late 70s and has become like Kool-Aid, Band-aid, and Q-Tip.  There are many other brands of IR cameras, we use FLIR and Fluke mostly at work.  I have the top of the line P series version that has high resolution, standard imaging, IR imaging, storage memory, and PC connectivity.  Overkill for what I use it for, but the company had deep pockets at one time and bought the best.
 
2013-05-02 05:48:40 PM  
We wouldn't be so smug if he had remembered to bring his tinfoil hat.
 
2013-05-02 05:51:51 PM  
Should have covered himself in mud after creating a lot of clever spear-based booby traps.
 
2013-05-02 05:57:00 PM  
I took a training course on the Avenger missile system a long time back, and one of the instruments on the turret was a FLIR.  I don't know if they changed the design yet, but the control panel for turning it on had two switches and a light.  You'd flip one switch to activate it, then wait for the light to come on, indicating that the tube or whatever was cooled down, at which point you could flip the other switch to start seeing IR.  Flipping switch #2 before the light came on was said to cause irreversible damage to the $10,000 tube.

The funny thing is, and I'm just a simple farm boy, but if I was hacking this thing together in my garage, I would have replaced switch #2 with a relay that was wired to the light so forgetful grunts couldn't fark it up.  But that's the quality a billion dollar military contract buys, I suppose.
 
2013-05-02 06:05:17 PM  

waterrockets: buttery_shame_cave: fun fact: spandex is transparent in the infra-red part of the spectrum.

IR filters are actually very easy to make.

Yes, but not with the same results seen in a FLIR system. Filtering out all wavelengths outside FLIR doesn't modify the intended wavelengths and intensities to record by your camera.


yeah, i know.

but i figured the threadjack would be welcome knowledge to the clever ones among us given how summertime is approaching, and a set of DIY IR filters can be made to look KIND of like very heavy sunglasses if you're REALLY crafty.
 
2013-05-02 06:07:39 PM  

ausfahrk: I took a training course on the Avenger missile system a long time back, and one of the instruments on the turret was a FLIR.  I don't know if they changed the design yet, but the control panel for turning it on had two switches and a light.  You'd flip one switch to activate it, then wait for the light to come on, indicating that the tube or whatever was cooled down, at which point you could flip the other switch to start seeing IR.  Flipping switch #2 before the light came on was said to cause irreversible damage to the $10,000 tube.

The funny thing is, and I'm just a simple farm boy, but if I was hacking this thing together in my garage, I would have replaced switch #2 with a relay that was wired to the light so forgetful grunts couldn't fark it up.  But that's the quality a billion dollar military contract buys, I suppose.


My first exposure (ha) to them was when I was in the Army in Germany 89ish.  The Chapparal systems were getting them as an upgrade and Stinger/Redeye had them also I believe. My Vulcan had shiatty doppler that sucked.  The Navy got it right adding FLIR and better servos to move the cannon faster and with better resolution.

If it booted itself up with no human interaction, it wouldn't break as much and then the company couldn't charge $10K to fix it.
 
2013-05-02 06:14:01 PM  

This About That: Russ1642: So why is it still called forward looking if they're mounted in a way that lets you point it wherever you like?

Conspiracy theory #1: Back in the day, while the equipment was heavier and rigidly mounted to the helicopter, it looked looked downward. Then someone developed a system that was mounted so that it looked forward, maybe looking for missiles and other threats in the flight path. Pilots were greatly impressed by the system, which they came to know as FLIR (forward-looking infrared). Marketers, knowing this, kept on using the acronym to sell product long after it no longer made any sense.


My version (would love to hear the correction on this for the geek in me):
IR is heat. Everything emits some level of heat. The camera has to be calibrated to receive in only one specific direction, or else the heat just from the atmosphere could blind the camera (think glare overload).
 
2013-05-02 06:17:32 PM  

Peki: This About That: Russ1642: So why is it still called forward looking if they're mounted in a way that lets you point it wherever you like?

Conspiracy theory #1: Back in the day, while the equipment was heavier and rigidly mounted to the helicopter, it looked looked downward. Then someone developed a system that was mounted so that it looked forward, maybe looking for missiles and other threats in the flight path. Pilots were greatly impressed by the system, which they came to know as FLIR (forward-looking infrared). Marketers, knowing this, kept on using the acronym to sell product long after it no longer made any sense.

My version (would love to hear the correction on this for the geek in me):
IR is heat. Everything emits some level of heat. The camera has to be calibrated to receive in only one specific direction, or else the heat just from the atmosphere could blind the camera (think glare overload).


IIRC, the ground has a lot more IR signature than the sky.  Avengers have an auto-tracking mode that used to go nuts if you tracked a plane too close to the horizon and let the FLIR lock onto the hills.  (Nuts, like the turret would start bouncing around wildly until you disabled the tracking.)
 
2013-05-02 06:21:20 PM  

Cthulhu_is_my_homeboy: Yet, Iraqis figured out how to disguise their foxholes from FLIR in gulf war 2 by using heavy blankets. It all depends on the material.

My first instinct, if I needed a lightweight material to block FLIR, would be to find something like mylar--coated in aluminum or gold on one side, it should be fairly reflective all across the near-visual part of the spectrum. Failing that? IDK. Polartec fleece? Stuff does a pretty good job of keeping body heat in, though it might be too porous. Apparently common plastic tarps are right out, as the article shows. Could drenching yourself in cold water reduce your heat signature to background levels? Maybe mud, Predator style?

These "eye of god" technologies are pretty damn scary.


There's still enough of a ...temperature...difference

It's really based on wavelengths, not degrees like a thermometer
 
2013-05-02 06:35:06 PM  
My fire department has two thermal cameras

They are really useful in searching a smoke filled building.   On a car accident, they can show you where skid marks started in the dark too.

We have used them on search and rescues outside too.    Lots more animals around at night than I was aware of.
 
2013-05-02 06:35:27 PM  
Peki:

My version (would love to hear the correction on this for the geek in me):
IR is heat. Everything emits some level of heat. The camera has to be calibrated to receive in only one specific direction, or else the heat just from the atmosphere could blind the camera (think glare overload).


To an extent. At the time of development most radar and tracking was Doppler and Sonar and sweeping in a 360 around the dish.  It needed to bounce off something as the dish rotated to work, after each sweep it would update the location of the tracked object. The target also need enough mass to be picked up by the Doppler ping.

IR Cameras could be pointed a target, sense it almost immediately, and then track it based on the heat movement with a better accuracy than sweeping Doppler.  The atmosphere has no emissivity to put off detectable heat in the IR spectrum.
 
2013-05-02 06:36:45 PM  

ausfahrk: Peki: This About That: Russ1642: So why is it still called forward looking if they're mounted in a way that lets you point it wherever you like?

Conspiracy theory #1: Back in the day, while the equipment was heavier and rigidly mounted to the helicopter, it looked looked downward. Then someone developed a system that was mounted so that it looked forward, maybe looking for missiles and other threats in the flight path. Pilots were greatly impressed by the system, which they came to know as FLIR (forward-looking infrared). Marketers, knowing this, kept on using the acronym to sell product long after it no longer made any sense.

My version (would love to hear the correction on this for the geek in me):
IR is heat. Everything emits some level of heat. The camera has to be calibrated to receive in only one specific direction, or else the heat just from the atmosphere could blind the camera (think glare overload).

IIRC, the ground has a lot more IR signature than the sky.  Avengers have an auto-tracking mode that used to go nuts if you tracked a plane too close to the horizon and let the FLIR lock onto the hills.  (Nuts, like the turret would start bouncing around wildly until you disabled the tracking.)


Actually, now that I think of it, it wasn't using the FLIR for that, it was using the IR seeking heads in the missiles.  Same difference, though.
 
2013-05-02 06:40:16 PM  
3.bp.blogspot.com //hot
 
2013-05-02 06:43:18 PM  
We run 2nd generation thermals in our M1A1(SA) and M1A2 tanks.   Pretty impressive - until it rains or snows, or a heavy fog comes in.    Also fun - I haven't figured out what exactly is doing it yet, but certain wavelengths seem to be mistaken by a directed energy attack by the sight - and it slams down the filters and you can't see squat.
 
2013-05-02 06:49:00 PM  

Peki: My version (would love to hear the correction on this for the geek in me):
IR is heat. Everything emits some level of heat


The first part is wrong. "IR" is a section of the electromagnetic spectrum with a wavelength longer than visible red light and shorter than wherever you assign the next category (e.g. microwaves). Your television remote control produces IR using the same type of light-emitting diode that's used as a visible indicator, just emitting at a different wavelength. This is not "heat".

Hot objects radiate electromagnetic energy across a range of wavelengths, with a peak intensity at a wavelength related to their temperature. For the surface of the sun this peak is in the visible spectrum. For an object at human body temperature it's in the IR range, which is where the "IR = heat" confusion comes from. Extremely cold objects will have a peak emission in the microwave spectrum, e.g. the cosmic background radiation.

If you want a demonstration that IR and heat are different, just stick your hand into an intense green laser beam (e.g. from an argon laser). It's entirely visible light, no infrared, but it will still provide plenty of heat.
 
NFA [TotalFark]
2013-05-02 06:51:30 PM  
It astounds me that people didn't know about thermal imagers.  You can buy relatively cheap thermal imagers for 1 or 2 thousand dollars but with lower resolution than the 1/4 of a million dollar units.  The cheap units work very well, are handheld and take digital images.

I have an i5.  They're simply amazing.
 
2013-05-02 06:56:47 PM  

Cthulhu_is_my_homeboy: Yet, Iraqis figured out how to disguise their foxholes from FLIR in gulf war 2 by using heavy blankets. It all depends on the material.

My first instinct, if I needed a lightweight material to block FLIR, would be to find something like mylar--coated in aluminum or gold on one side, it should be fairly reflective all across the near-visual part of the spectrum. Failing that? IDK. Polartec fleece? Stuff does a pretty good job of keeping body heat in, though it might be too porous. Apparently common plastic tarps are right out, as the article shows. Could drenching yourself in cold water reduce your heat signature to background levels? Maybe mud, Predator style?

These "eye of god" technologies are pretty damn scary.


Less scary if you are a mote.
 
2013-05-02 07:09:18 PM  

Ivo Shandor: It's entirely visible light, no infrared, but it will still provide plenty of heat.


I've been trying to formulate a response three times now. First off, when I said heat, I meant in the sense of "above absolute zero."

Second: So is there something that exists that is only visible in the IR spectrum but could give out the same amount of heat as a laser? If there isn't, then I would next posit that IR camera = a thermometer that only works in certain temperature ranges, and then translates the temps into visible light for us to see.
 
2013-05-02 07:30:02 PM  
Car_Ramrod: I actually did not know that you can't use thermal imaging to look through windows

MythBusters showed it during their "foil security measures" episode.

// carry a pane of glass between you and an infrared camera, but do it quickly before you warm up the glass.

http://dsc.discovery.com/tv-shows/mythbusters/mythbusters-database/t he rmal-cameras-unbeatable.htm
 
2013-05-02 07:44:34 PM  

Peki: I've been trying to formulate a response three times now. First off, when I said heat, I meant in the sense of "above absolute zero."

Second: So is there something that exists that is only visible in the IR spectrum but could give out the same amount of heat as a laser? If there isn't, then I would next posit that IR camera = a thermometer that only works in certain temperature ranges, and then translates the temps into visible light for us to see.


Maybe a better way of phrasing it is that IR is an indication of heat rather than being the same thing as heat.

There's also more than one type of IR camera. There are the thermal-imaging ones which operate as you described, but there are also non-thermal night vision cameras which operate at shorter wavelengths (closer to visible light) and rely on LEDs or infrared lamps to illuminate the scene. These are used as security cameras or to observe wildlife, when you don't want the target to know that it's being watched.
 
2013-05-02 07:48:29 PM  

Peki: Ivo Shandor: It's entirely visible light, no infrared, but it will still provide plenty of heat.

I've been trying to formulate a response three times now. First off, when I said heat, I meant in the sense of "above absolute zero."

Second: So is there something that exists that is only visible in the IR spectrum but could give out the same amount of heat as a laser? If there isn't, then I would next posit that IR camera = a thermometer that only works in certain temperature ranges, and then translates the temps into visible light for us to see.


Almost.  It emits a wavelength that can be measured in the IR spectrum and that can be translated into visible images and then you could possibly calculate temperature based on Emissivity and Reflectivity.

As an example, I cast bullets from lead alloy.  When its over 600F and surface is skimmed, it is like a perfect mirror.  If I point an IR camera at the pool, it will show the IR signature of whatever is reflecting in the pool because of the high reflectivity not the temp of the melt.  If I am facing into it, it will show me in the pool.  Now if I drop a piece of dark and tarnished metal into the pool and allow it to come to equilibrium with the alloy, I can then shoot the foreign object with low to no reflectivity and high emissivity and calculate the approximate temp to the exact temp if exact E and R are known.  The FLIR handhelds will calculate it for you if you input the E/R, but what you see on the display is not actual heat.
 
2013-05-02 07:51:20 PM  

Calehedron: Certified Thermographer w/ $65K FLIR camera at work.


You ever just spend a day playing with the thing (which I would  never do with mine...)? Water towers are pretty cool outside, or finding a good room to bounce a super ball around and see the hot spots on the walls, or "writing" in invisible body-heat ink on a blank wall, or looking at boiling water in a clear tea kettle thing.

//That was a fun day.
//Don't have it anymore.....
 
2013-05-02 07:56:10 PM  

Calehedron: The FLIR handhelds will calculate it for you if you input the E/R, but what you see on the display is not actual heat.


Understood, and I didn't think it was an equivalent to a thermometer. But I didn't think I was that off in thinking that heat from sources outside the field of view would fark with an IR camera.

Thanks to both of you for the clarification.
 
2013-05-02 08:16:22 PM  

dukeblue219: You ever just spend a day playing with the thing (which I would never do with mine...)? Water towers are pretty cool outside, or finding a good room to bounce a super ball around and see the hot spots on the walls, or "writing" in invisible body-heat ink on a blank wall, or looking at boiling water in a clear tea kettle thing.

//That was a fun day.
//Don't have it anymore.....


Yessir, you can see some pretty cool stuff with it.  The instructor of the cert class could tell who the smokers were by scanning their hands and showing the lowered circulation in relation to non-smokers.  He showed us someones rebuilt knee and shoulder, how the bloodflow, thus heat, is different around a repaired or damaged joint.  You can search for draft leaks in your house just after dark from the outside.

Another prime example of what an IR camera can and cannot see is taking a stainless steel or other shiny metal gallon can and wrap the bottom half in black latex electrician tape (E is almost a 1 and R is almost 0) and then filling it with hot water.  When you scan the top half with no tape you will see your ~85-90F IR reflection but the taped area will clearly show the warmer IR signature of the water inside.
 
2013-05-02 08:36:00 PM  
I keep seeing this term: "shelter in place"

I swear that I remember them calling it "shelter safe" and not "shelter in place" but I can't seem to find any of the press conferences from the actual day of the manhunt.
 
2013-05-02 08:46:01 PM  

Cthulhu_is_my_homeboy: My first instinct, if I needed a lightweight material to block FLIR, would be to find something like mylar--coated in aluminum or gold on one side, it should be fairly reflective all across the near-visual part of the spectrum.


www.lhasaoms.com
 
2013-05-02 09:24:09 PM  
Smidge204: Cthulhu_is_my_homeboy: My first instinct, if I needed a lightweight material to block FLIR, would be to find something like mylar--coated in aluminum or gold on one side, it should be fairly reflective all across the near-visual part of the spectrum.

On the package itself, it says 80%. That means 20% still goes through.

Thermodynamics wins every time.
 
2013-05-02 09:24:11 PM  

itsa_revolution: First of all, they say that it was the State Police, then  change their tune and say it was the boston police department in the photo caption.  Conspiracy or just shiatty journalism?  You decide.

Second, they tell us that the video was not being streamed down to the ground when we know that it was (at least the internet does).  That's just straight conspiracy right there.


It was a state police helipcopter.

The other cops couldn't see the image.  We heard on the radio from the chopper, "There is no movement."  "There is movement."

What's weird is the copter telling them they had to circle and climb before they put the night sun on the boat.  I guess they wanted to back off out of handgun range?
 
2013-05-02 09:43:36 PM  

lordargent: Smidge204: Cthulhu_is_my_homeboy: My first instinct, if I needed a lightweight material to block FLIR, would be to find something like mylar--coated in aluminum or gold on one side, it should be fairly reflective all across the near-visual part of the spectrum.

On the package itself, it says 80%. That means 20% still goes through.

Thermodynamics wins every time.


If you fold it in half you can block 160%, right?
 
2013-05-02 10:00:25 PM  
ausfahrk: If you fold it in half you can block 160%, right?

Theoretically**, the first layer would block 80%, and the second layer would block 80% of what passed through the first layer.

But in practice, it's probably more complicated than that.

** this theory is based on damage bleed through calculations from a few RPGs and may not reflect the real world. But that's why I'm a programmer and not a physicist (actually, I was leaning heavily toward chemistry, but life carried me in another direction).
 
2013-05-02 10:14:59 PM  

lordargent: Smidge204: Cthulhu_is_my_homeboy: My first instinct, if I needed a lightweight material to block FLIR, would be to find something like mylar--coated in aluminum or gold on one side, it should be fairly reflective all across the near-visual part of the spectrum.

On the package itself, it says 80%. That means 20% still goes through.

Thermodynamics wins every time.


No IR signature gets through, it reflects 80% of the heat back to the source whether inside or out..  You lose 20% efficiency of your body heat to keep you warm with it around you instead of lots more with no covering at all.  If scanned from the outside and you were in the direct reflection of the blanket it would show your signature as your skin temp - 20% but nothing of anything inside of the blanket.

Lots of indoor gardeners and MMJ cultivators use these blankets or a product called Reflectix (Silver Mylar on bubble wrap to break up the surface to scatter the light) to line the walls of their grow rooms.  If reflects the grow light at 80% efficiency and blocks external heat scans.
 
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