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Laser Camera Can See Around Corners

timothy posted more than 3 years ago | from the good-skill-to-pick-up dept.

Science 97

Hugh Pickens writes "Researchers at MIT have developed a laser camera that can 'see' around corners and take pictures of a scene not in its direct line of sight. The camera system fires extremely short bursts of light that can reflect off one object, such as the open door of a room, and then off a second object inside the room before reflecting back to the first object and being captured by the camera, after which algorithms can use the information to reconstruct the hidden scene exploiting the fact that it is possible to capture light at extremely short time scales, about one quadrillionth of a second. By continuously gathering light and computing the time and distance that each pixel has traveled, the camera creates a '3D time-image' of the scene it can't directly see. 'It's like having X-ray vision without the X-rays,' says Professor Ramesh Raskar. 'We're going around the problem rather than going through it.'"

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No images (0)

Anonymous Coward | more than 3 years ago | (#34279996)

Why articles like these do not have any related images?

Re:No images (1)

Seriousity (1441391) | more than 3 years ago | (#34280024)

Because they do not yet have access to the technology in question, and cannot see around the corner of industry delay?

Re:No images (5, Informative)

HateBreeder (656491) | more than 3 years ago | (#34280026)

Re:No images (1)

teslar (706653) | more than 3 years ago | (#34280504)

Indeed. And based on that pic, you can see (or not - no pun intended) why there wasn't a pic in the other write-ups. As the BBC article says:

At the moment, the set-up only works in controlled laboratory conditions and can get confused by complex scenes. "It looks like they are very far from handling regular scenes," said Prof Nayar. In everyday situations, he said, the system may compute "multiple solutions" for an image, largely because it relied on such small amounts of light and it was therefore difficult to extrapolate the exact path of the particle as it bounced around a room.

Re:No images (1)

timeOday (582209) | more than 3 years ago | (#34281756)

For another image (or if you just want a lot more detail and a LOT more hype) here's a presentation by the researcher [youtube.com] .

Re:No images (2, Funny)

TheLink (130905) | more than 3 years ago | (#34282802)

I actually find the eye-test thing in the later part more interesting.

A "looking round the corner" device is likely to be very expensive and so only useful to a few people.

TSA can look up your trousers (2, Funny)

ciaran_o_riordan (662132) | more than 3 years ago | (#34280090)

Great, so instead of x-raying or groping travellers, maybe TSA can subtly take a few snaps up the leg of people's trousers and down the top of your t-shirt :-)

http://www.prisonplanet.com/tsa-now-putting-hands-down-fliers-pants.html [prisonplanet.com]

http://www.wired.com/threatlevel/2010/11/tsa-investigating-passenger/ [wired.com]

Re:TSA can look up your trousers (1)

Luckyo (1726890) | more than 3 years ago | (#34283518)

+1 Scary.

Re:TSA can look up your trousers (1)

K. S. Kyosuke (729550) | more than 3 years ago | (#34284238)

TSA = Testicle Scrutinizing Authority?

Re:TSA can look up your trousers (0)

Anonymous Coward | more than 3 years ago | (#34285120)

Touching Some Ass?

NOT Funny (1)

droidsURlooking4 (1543007) | more than 3 years ago | (#34286102)

f'd up moderators here.

Now imagine that (0)

Anonymous Coward | more than 3 years ago | (#34280092)

attached to the head of a shark! With a CornerShot! I bet that would make Dr Evil wet his pants

It's like having X-ray vision without the X-rays (5, Funny)

Anonymous Coward | more than 3 years ago | (#34280102)

It's like having X-ray vision without the X-rays...

So it's like having vision?

Here's a link to the actual MIT site... (5, Informative)

Anonymous Coward | more than 3 years ago | (#34280106)

http://web.media.mit.edu/~raskar/femto/ [mit.edu]

Enough of Slashdot's SEO link farming spammy shit. Here's what you want to read, unless you like your science news dumbed down to a third grade level.

Re:Here's a link to the actual MIT site... (3, Funny)

icebraining (1313345) | more than 3 years ago | (#34280192)

[quote]Light travels 1 foot/nanosecond(...)[/quote]
How much is that in Libraries of Congress?

Really, foots per nanosecond? I thought it was a scientific experiment.

C is exactly 299792458 ms.

Re:Here's a link to the actual MIT site... (1)

dreamchaser (49529) | more than 3 years ago | (#34280270)

You were modded funny but you should have been modded pedantic. If you really want to be pedantic you should have pointed out that in an atmosphere or other non-vacuum medium it is slower than theoretical C. Second, one foot is a very good approximation of the speed of light and perfectly suitable to use in a non-journal science article. Seriously, if you're going to nitpick like that you really need to get a life and move out of your mother's basement.

Re:Here's a link to the actual MIT site... (1)

Jon Abbott (723) | more than 3 years ago | (#34281716)

Continuing the pedantry a bit further, the speed of light is denoted as c, not C.

Re:Here's a link to the actual MIT site... (1)

Scatterplot (1031778) | more than 3 years ago | (#34282826)

Also, the plural of "foot" is "feet", not "foots".

Re:Here's a link to the actual MIT site... (0)

Anonymous Coward | more than 3 years ago | (#34281938)

What the heck is a foot?

Re:Here's a link to the actual MIT site... (1)

Metrathon (311607) | more than 3 years ago | (#34283226)

foots is what you should wonder about

Re:Here's a link to the actual MIT site... (0)

Anonymous Coward | more than 3 years ago | (#34284190)

It's an old term that isn't widely used anymore, but there are approx 3.28 of them in a metre.

Re:Here's a link to the actual MIT site... (0)

Anonymous Coward | more than 3 years ago | (#34291528)

Second, one foot is a very good approximation of the speed of light [...]

I would like to subscribe to your journal, in which units of length are units of speed.

Re:Here's a link to the actual MIT site... (1)

MightyYar (622222) | more than 3 years ago | (#34280310)

There's nothing wrong with writing for your audience. If you see ft/ns in "Nature", feel free to flame.

Re:Here's a link to the actual MIT site... (0)

Anonymous Coward | more than 3 years ago | (#34280480)

Light travels 1 foot/nanosecond and by sampling the light at pico-second resolution, we can estimate shapes with centimeter accuracy

I think they reduced the scale to compare foots with centimeters and nanoseconds with picoseconds (1/1000 of a nanosecond), insteand of millions of meters with centimeters and seconds with picoseconds (1/1000000000000) and make it easier to get a mental image of what's going on.

Re:Here's a link to the actual MIT site... (1)

icebraining (1313345) | more than 3 years ago | (#34280374)

Damn /. eating my superscript. It's m/s.

Re:Here's a link to the actual MIT site... (3, Funny)

argStyopa (232550) | more than 3 years ago | (#34281234)

"C is exactly 299792458 ms" ...which is precisely as arbitrary, if more widely accepted, than cubits per moon phase.

I swear, metric evangelism is becoming more rabid every week. Oh wait, I'm sorry, it's becoming more rabid every 2/100ths of a year.

Re:Here's a link to the actual MIT site... (1)

icebraining (1313345) | more than 3 years ago | (#34281842)

It's not, because the meter is defined by c, so in this particular case, it offers a precise value.

In 1983 the metre was defined as "the length of the path traveled by light in vacuum during a time interval of 1299,792,458 of a second", fixing the value of the speed of light at 299,792,458 m/s by definition

Re:Here's a link to the actual MIT site... (1)

ArsonSmith (13997) | more than 3 years ago | (#34283368)

sure would have been nice if they fixed it at 300,000,000 m/s as it would be pretty damn close to where it is now anyway and the number would be much easier to remember.

Re:Here's a link to the actual MIT site... (1)

SleazyRidr (1563649) | more than 3 years ago | (#34284434)

Find a better source. The metre still hasn't been tied to anything tangible.

Re:Here's a link to the actual MIT site... (1)

icebraining (1313345) | more than 3 years ago | (#34285206)

Uh, yes it was, in the 17th general conference of the International Committee for Weights and Measures.

http://www.bipm.org/en/CGPM/db/17/2/ [bipm.org]

Re:Here's a link to the actual MIT site... (1)

argStyopa (232550) | more than 3 years ago | (#34284708)

"Distance traversed in vacuum by light in 1/299792458 of a second"

Wow, you sure proved me wrong. That's not arbitrary at ALL.
Of course, that was the definition in 1983.

Of course, in 1960 it was "Hyperfine atomic transition; 1650763.73 wavelengths
of light from a specified transition in Krypton 86 (11th CGPM)" ...Which isn't arbitrary.

"Platinum-iridium bar at melting point of ice, atmospheric pressure, supported by two rollers (7th CGPM)" (1927)

Nope, not arbitrary either.

I'm so embarrassed at my obvious ignorance.

Re:Here's a link to the actual MIT site... (0)

Anonymous Coward | more than 2 years ago | (#34305076)

Not arbitrary? So why didn’t they define it 1/300,000,000th of a second? or 1/299,792,460th, or 1/299,800,000th, or 1/299,792,457th or 1/299,792,459th for that matter?

Re:Here's a link to the actual MIT site... (1)

The_mad_linguist (1019680) | more than 3 years ago | (#34283878)

C is exactly 299792458 ms.

The speed of light is 3.46982012 days?

Can you do the Kessel run in less than twelve parsecs?

Re:Here's a link to the actual MIT site... (0)

Anonymous Coward | more than 3 years ago | (#34280834)

Whoa, is that Word clipart on a MIT site?

Re:Here's a link to the actual MIT site... (1)

mcgrew (92797) | more than 3 years ago | (#34280936)

Yes, that's been annoying me at work. Most of the links are firewalled off, but I can usually find a better FA with Google. With dozens or hundreds of stories written by professionals and posted on sites that can handle a slashdotting, why do these stories link to some blog that merely quotes a mainstream news source, is firewalled off in many places, and is frequently slashdotted to oblivion?

Firehosers, I'm calling on you all to turn these down. I'll bet there were half a dozen submissions of this same story.

Pics (1, Funny)

Anonymous Coward | more than 3 years ago | (#34280120)

or it didn't happen!

Pics or shens. (1)

ryanhanks (1132611) | more than 3 years ago | (#34280122)

ssia

As I see it.. (1)

angiasaa (758006) | more than 3 years ago | (#34280184)

It would make a helluva lot more sense to just use high-intensity microwaves. Think of how Dolphins and bats see their environment. the device to see around corners would have to take various additional factors into account of course, like distance from the reflecting surface and angle of beam contact to said surface. After that, it's just a matter of painting a 3d version of the room. :|

Re:As I see it.. (0)

Anonymous Coward | more than 3 years ago | (#34281524)

This is just so wrong. There is cluelessness packed into every sentence. Microwaves? Following sentence is about unnecessarily captialized echolocating mammals? various additional factors like distance and angle are used for nothing in variously handwavy particular. After all the ??? is accounted for, it's just a matter of drawing a picture (yay pictures).

Hmmmm... (2, Interesting)

tygerstripes (832644) | more than 3 years ago | (#34280194)

The process has to be incredibly time-sensitive in order to work, and the imaging process has to subtract ambient light in order to obtain the reflected-laser data. This ambient-light recording has to happen at a different time to when the laser is fired, so variable-light conditions or the lack of an incredibly steady camera, image object and reflective surface will make it basically impossible to render the image.

I absolutely love the concept. I just think that the nay-sayers whom Professor Raskar claims to be defeating were correct. It might not be theoretically impossible, but the practical limitations are so severe that I don't envisage them being "engineered" away - and if they are, such phenomenal engineering accomplishments would make this application appear trivial in comparison with the other things we could do.

Re:Hmmmm... (1)

Shrike82 (1471633) | more than 3 years ago | (#34280382)

Indeed, not to mention the limitation that you need a surface off of which you bounce the intitial laser pulse. This "looking round corners" idea/phrase someone has put forward is total crap. Sure, you can look around a corner as long as it's (e.g.) a doorframe and the door opens outwards in the right direction for your camera to use as a reflector. Want to look round the corner of a building? Into a room where the door opens inwards? Over a wall? Then you're shit out of luck.

Once again the media takes a story and dumbs it down to the point where most people get entirely the wrong idea.

Re:Hmmmm... (0)

Anonymous Coward | more than 3 years ago | (#34280954)

Well it is interesting that ray-tracing can actually be done with real photons. The way this process is described, it seems to work like how cameras do in most 3D software. (The notable difference being that they tweaked the reflection algorithm a bit to ignore matte materials.) It's likely to have some of the same disadvantages too.

Why not use sound? (sonar) (1)

wisebabo (638845) | more than 3 years ago | (#34281082)

If it has to be incredibly time sensitive to work why not use sound (ultra-sonic waves, like bats use) instead. This should reduce the time sensitivity requirements by many orders of magnitude. It will also reduce the resolution but considering that bats can catch insects in flight probably will still be good enough to "see" someone hiding behind a door.

Or perhaps they need a coherent (laser) beam of sound? Perhaps this can be engineered around. Might also be useful underwater.

Re:Hmmmm... (2, Insightful)

Lluc (703772) | more than 3 years ago | (#34281458)

Given that he's using a femtosecond laser and some kind of exotic "streak" camera, I think he has to essentially raster scan the area he's imaging "around the corner". I doubt the ambient lighting or the scene itself will change in a femtosecond, but the raster-scanner better move pretty fast! A fast raster-scanner might be solvable, even. I think the biggest problem he's going to have is dealing with a non-sparse scene. I think this works well for simple geometries, but once he starts dealing with a really complicated scene, there will be too many possibilities to sort out for each given measurement. (Too many variables!)
I wonder how many real scientific "nay-sayers" he really had to deal with -- in his publication he states that this project is an extension of LIDAR work that was done 10+ years ago. I think it's very cool academic research, but I also think that MIT Media Lab *loves* to hype the every-day/year cool engineering project as though it's a complete world changer.

Re:Hmmmm... (1)

Timmmm (636430) | more than 3 years ago | (#34281726)

This ambient-light recording has to happen at a different time to when the laser is fired, so variable-light conditions or the lack of an incredibly steady camera, image object and reflective surface will make it basically impossible to render the image.

Yeah but you could record the ambient light 1 ms later. Light is pretty damn fast and ambient light conditions are essentially constant.

I absolutely love the concept. I just think that the nay-sayers whom Professor Raskar claims to be defeating were correct. It might not be theoretically impossible, but the practical limitations are so severe that I don't envisage them being "engineered" away - and if they are, such phenomenal engineering accomplishments would make this application appear trivial in comparison with the other things we could do.

I wouldn't be so sceptical. The main limitations are:

1. Miniaturisation. Obviously this is just an engineering problem. A damn hard one, sure.
2. Sampling rate of the light signal. This is the one that will really determine the image quality.

The door requirement is a pretty big limitation though. I think a fibre optic camera poked around the corner might be a bit easier!

Re:Hmmmm... (1)

poilupoteux (630101) | more than 3 years ago | (#34282744)

Engineering a methodology that would permit te reverse compose images of the Big Bang reflected on objects out of its event horizon would be non trivial.

Re:Hmmmm... (1)

Technician (215283) | more than 3 years ago | (#34284156)

I took a look at their supplied graphic and immediatly had a few issues with it. #1 starts with reflection one. Is the door a mirror or is is a surface that will scatter the light into all the room? Same for reflection 2. Think about reflection 2 for a moment. Remember the problem with reflection 1? Which reflection 2? Multiply for reflection 3 and you have no immage, but just a depth sounding ping return from the room with no direction information at all, thus no shape information, only the return times of all the scattered reflections. You can get an accurate ping time for the door, then everything from the door to the floor to the walls, roof, objects, in the room, and such all blend together as their mixed returns blend.

Re:Hmmmm... (1)

WildBlueYonder (1714974) | more than 3 years ago | (#34284262)

Assuming your ambient light isn't coming from a laser wouldn't you be able to get rid of the light by filtering out any non-polarized light? If there are lasers (say multiple people in a SWAT team are using this) as part of the ambient light maybe each could be using a slightly different wavelength of light in order to filter out the other devices as well.

Re:Hmmmm... (1)

celtic_hackr (579828) | more than 3 years ago | (#34287976)

Actually, it sounds like an alternate way of recording a holographic image. The one thing I don't see mentioned is it becomes increasingly more difficult to make this work, the less smooth and flat your reflecting surface gets. In fact, I'd be surprised if this was even feasible if you are reflecting the laser beams off anything that isn't significantly flat and smooth.

And guess what (4, Insightful)

Rosco P. Coltrane (209368) | more than 3 years ago | (#34280212)

The first customer will either be the TSA or some branch of the military.

High-tech companies would invent anything that would sell to any agency vaguely related to counter-terrorism or warfare these days. If they poured a tenth of the resources they spent developing this kind of devices into finding solutions to the world's real problems, we'd all be cancer-free and solar-powered by now...

Re:And guess what (3, Insightful)

Pieroxy (222434) | more than 3 years ago | (#34281766)

...we'd all be cancer-free and solar-powered by now...

and under the reign of the Queen of England.

Re:And guess what (1)

RocketRabbit (830691) | more than 3 years ago | (#34285174)

Better check which banks own the Federal Reserve, buddy. Guess what? Some of them are in London.

The information is difficult to obtain but if you want a wild ride you should research the issue yourself.

hearsay (5, Informative)

ei4anb (625481) | more than 3 years ago | (#34280222)

Slashdot says that UPI.com said that physorg.com said that Tech Radar said that MIT said that there is an interesting paper at http://dspace.mit.edu/bitstream/handle/1721.1/58402/656284100.pdf?sequence=1 [mit.edu] and the BBC went to learn more, conduct an interview and take photos http://www.bbc.co.uk/news/technology-11544037 [bbc.co.uk]

Re:hearsay (1)

rrohbeck (944847) | more than 3 years ago | (#34284226)

Meh. BBC. Old and proven news organizations. Who needs them? This is the Internet, all we want is hearsay.

Still no good. (1)

MrQuacker (1938262) | more than 3 years ago | (#34280234)

Unless I can use it to "see" through the walls of the girls locker-room, then its not X-Ray vision.

Re:Still no good. (1)

Rosco P. Coltrane (209368) | more than 3 years ago | (#34280248)

Unless I can use it to "see" through the walls of the girls locker-room, then its not X-Ray vision

You didn't specify if the girls in the locker room should remain unaware of your watching them. Cuz if don't, a large lump hammer is enough to see through the wall, no need for X-rays...

Re:Still no good. (1)

Combatso (1793216) | more than 3 years ago | (#34280354)

or a window... a glass wall is still a wall

Enter terminator robots with glowin' eyes. (0)

Anonymous Coward | more than 3 years ago | (#34280244)

Now you know why their eyes are a'glowin'.

New Glasses and Windshields (1)

digitaldc (879047) | more than 3 years ago | (#34280288)

I can see this being applied to lenses and windshields to give you an idea of who or what is lurking around the corner... [hilariousheadlines.com]

Pix (0)

Anonymous Coward | more than 3 years ago | (#34280412)

Pix or it didn't happen.

Blade Runner (2)

Digital Vomit (891734) | more than 3 years ago | (#34280442)

Now that scene in Blade Runner is making more sense...

Re:Blade Runner (1)

Jabrwock (985861) | more than 3 years ago | (#34281134)

I thought the exact same thing.

Re:Blade Runner (1)

mcgrew (92797) | more than 3 years ago | (#34281432)

Funny how impossibilities in science fiction become possible with time. When Star Trek came out in 1966, flat screen monitors, "communicatore", self-opening doors, talking computers, and a lot more stuff that's commonplace now was impossible then.

However, Blade Runner makes the Doctorow Mistake of setting the fiction too close to the present. It's set just ten years from now. It's doubtful this tech will be mature in ten years, and besides, you can't just feed a print into the scanner and see around corners... yet. It'll probably happen, but not with this tech.

Re:Blade Runner (1)

droidsURlooking4 (1543007) | more than 3 years ago | (#34286128)

Funny how impossibilities in science fiction become possible with time.

Everything from Dick eventually becomes possible.

Re:Blade Runner (0)

Anonymous Coward | more than 3 years ago | (#34285706)

The one with the Unicorn?

Another tool... (1)

MacGyver2210 (1053110) | more than 3 years ago | (#34280516)

I love how all the researchers materials are all "Humanitarian" and indicate that this will be used to help people (fires, safety, etc...).

I give it about 15 minutes before the government gets wind of it and turns it into a tool for mass invasion of privacy and uses it somehow in this ongoing war on our freedoms.

I would be more optimistic, but their track record isn't encouraging.

And somewhere... (1)

N0Man74 (1620447) | more than 3 years ago | (#34281966)

Some creep is now thinking, "now I don't have to put spycams on my shoes!"

Pizel travel??? (1)

BazilBBrush (1259370) | more than 3 years ago | (#34280538)

"By continuously gathering light and computing the time and distance that each pixel has traveled"

right, so pixels travel!?! wtf has happened to /. editors? have they any clue of science???

photons, depending on perspective, travel. pixels, are part of an image.

is slashdot going to become worse than the pseudo science of mythbusters????

First application: bring sun to (1)

ArsenneLupin (766289) | more than 3 years ago | (#34280548)

... where it doesn't shine:

However, he said, the team initially aim to use the system to build an advanced endoscope.

"It's an easy application to target," he said. "It's a nice, dark, damp and warm environment."

If the team get good results from their trials, he said, they could have a working endoscope prototype within two years.

How Fast Are Pixels? (0)

Anonymous Coward | more than 3 years ago | (#34280556)

"By continuously gathering light and computing the time and distance that each pixel has traveled"

Do pixels travel at the speed of light? I wonder what it feels like to get hit by a pixel. Are they larger or smaller than a photon? I am really curious about this, I didn't realize that a pixel was a physical phenomena. It looks like the photon has some competition.

Re:How Fast Are Pixels? (2, Informative)

natehoy (1608657) | more than 3 years ago | (#34281358)

Do pixels travel at the speed of light?

Depends on your refresh rate.

I wonder what it feels like to get hit by a pixel.

Depends on the resolution, and of course the refresh rate which determines velocity. Set a 24" monitor to 1x1 resolution with a 100MHz refresh rate, and it hurts like hell. Set it ag 32,700 x 27,000, not so much, unless you get hit by all of the pixels or the pixel you are hit by is at a very high refresh rate.

Are they larger or smaller than a photon?

Larger, silly, they're made of pixel dust.

Dupe research? (1)

jmorkel (952809) | more than 3 years ago | (#34280616)

Reminds me of Dual Photography [slashdot.org]

Opt-dar? (1)

a4r6 (978521) | more than 3 years ago | (#34280618)

This sounds like it's fundamentally the same as radar or sonar but using light instead.

Re:Opt-dar? (1)

John Hasler (414242) | more than 3 years ago | (#34281160)

And the algorithms should be applicable to radar and sonar in cluttered environments.

Re:Opt-dar? (1)

rrohbeck (944847) | more than 3 years ago | (#34284342)

Lidar. Cops use it every day except that they don't have 2D spatial resolution because they only need one dot to do a Doppler measurement and get your speed.

"Enhance that..." (1, Funny)

Anonymous Coward | more than 3 years ago | (#34280658)

Oh crap, CSI is real!?!

This is clearly just range sensing with cameras... (1)

zeroRenegade (1475839) | more than 3 years ago | (#34281274)

It is ridiculous to call this new technology. It is just another form range sensing that is being researched in universities all over the world. Light is still just electromagnetic radiation. I am sure there are lots of other projects doing the same this as this, but since it is from the MIT Media Lab it gets the "oooo, awww.." factor.

Using the backscatter from diffuse reflection is seriously limiting.

Radar systems are brutally prone to clutter, echoes, and interference. The system is limited by range, and a linear line of sight (from object to object in this case).

It will only produce a three dimensional image when in a closed environment. Otherwise it will only produce a front shadow of a figure.

It blows me away how often old technology is replicated in computer science and called new technology. Not that their software does not make it better (like some decent noise cancelling), but to call it "new" is like painting a white horse with black stripes and calling it a zebra.

Re:This is clearly just range sensing with cameras (1, Insightful)

Anonymous Coward | more than 3 years ago | (#34281434)

Do you know *any* new technology that is not related to an older one ? Me neither.

Re:This is clearly just range sensing with cameras (0)

Anonymous Coward | more than 3 years ago | (#34281508)

Except that what is retroactively called substantial progress should almost always be seen as painting a horse in retrospect. I expect the metaphor of cars as "horseless carriages" was part of their design and not just part of their marketing.

This is not to say all developments are equivalently important, just that at the time people are rarely accurate at assessing how important they truly will be short of some spectacular scenarios.

Ze goggles, zey do nothing! (1)

hweimer (709734) | more than 3 years ago | (#34281530)

TFP [mit.edu] mentions that the laser is operated at an average power of 425 mW. So I'd rather not be the guy standing round the corner getting hit in the eye with such a beam.

High speed optical scanner with low accuracy? (1)

design1066 (1081505) | more than 3 years ago | (#34281786)

This is great. Its an EDM. Surveyors and engineers have been using this technology for half a century, the only difference is they have been excluding these types of measurements deemed reflective inaccuracy. This is a neat idea.

reflection (1)

bobs666 (146801) | more than 3 years ago | (#34282306)

So this is like looking at a mirror. Or pointing a flashlight at a mirror and looking around a corner.

Different wavelength so the door looks like a mirror So why is this news?

Re:reflection (1)

Anonymous Coward | more than 3 years ago | (#34282502)

No, it is not in the least like looking at a mirror.

You flash the door. It travels at the speed of light. You get the reflection off the door in twice the distance to the door divided by the speed of light. After that, you open the shutter and start watching.

You then get secondary reflections off the door, as the flash which reflected into the room then reflects off objects in the room, back to the door, and reflects back to you. The intensity of the light reflecting off of the door at any point in time tells you how much stuff there was inside the room at that corresponding distance from the door. Of course the image is completely diffuse, so even knowing that an object reflected the light back to you, you have to process the diffuse image highly to figure out where the object was.

It’s more like radar. Time equals distance, and you create a 3D map. Except they’re using a laser instead of radio waves, and they’re also bouncing it off an extremely diffuse surface, which is far less than ideal.

Re:reflection (1)

kipb (529703) | more than 3 years ago | (#34288606)

AND they do the same looking at various places on the door, so they see the "distance map" image from various perspectives. This makes it more analogous to the door as a mirror, just as you'd look at various points on a mirror and see a reflected scene from the point of view of that spot on the mirror.

Old News. (1)

FiloEleven (602040) | more than 3 years ago | (#34282474)

I saw this on CSI like eight years ago.

So the CSI stuff might actually work? (1)

gurps_npc (621217) | more than 3 years ago | (#34282820)

That is, when they have the CSI on TV "enhance the photo, show me the reflection in the car side mirror" In real life, we can not, or rather COULD NOT do that. But with these special cameras, apparently we will be able to do it.

I'm sorry but this sounds like bullshit (0)

Anonymous Coward | more than 3 years ago | (#34282842)

Haven't read TFA, but without pictures it didn't happen.

Obligatory (1)

noidentity (188756) | more than 3 years ago | (#34283796)

Hmmm, I seem to remember this technology [youtube.com] from years ago...

Blade Runner (1)

jtnix (173853) | more than 3 years ago | (#34284174)

That scene with Deckard dissecting the photograph on his weird-ass computer and literally changing the angle and viewpoint arbitrarily always bugged me.

Now, not so much. It must have had an embedded holographic layer that took several angles.

Yeah, that's it.

See around corners? (1)

rundgong (1575963) | more than 3 years ago | (#34286388)

Is it really "seeing around corners" if it needs something that the light can bounce off? With a mirror in the right place I can also "see around corners"

I'm sure it's still a great engineering accomplishment, but I wouldn't call it seeing around corners
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