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JAXA Creates Camera That Can See Radiation
New submitter Ben_R_R writes "The Japan Aerospace Exploration Agency has created a camera that can 'see' radioactive contamination by detecting gamma rays emitted by radioactive cesium and other substances. The camera has been tested in the disaster evacuation zone around Fukushima. The image captures levels of radiation in six different colors and overlays the result over an image captured with a wide angle lens."
So where is the data on how accurate it actually is? How does it work???
For example, this is informative.
http://imagine.gsfc.nasa.gov/docs/features/exhibit/glast_exhibit.html
TFA about this device is useless.
When I readed the topic, I just tought "Oh, someone invented Camera what can see light, AMAZING!"
Of course I know it was only about ionizing radiation and not just anykind radiation like visible light.
Usually, you just put a scintillating crystal, e.g. thallium-doped sodium iodide, in front of your detector. Gamma photon hits crystal, crystal emits photon in the visual range, photomultiplier detects visual photon. TFA is somewhat silent on how this differs from your run of the mill gamma camera which has been known for half a century by now.
Ubi solitudinem faciunt, pacem appellant.
Oh great, now we're going to be overwhelmed with Japanese tourists taking pictures of radioactive things!
Shot 1: Dad and the kids smiling at camera and glowing in dark.
Shot 2: Look! Our Toyota doesn't need headlights!
Shot 3. Mr. Fujimoto and his radioactive shoes!
Shot 4. Godzilla. No, really, Godzilla. Run!
The big difference is that a scintillator or geiger tube is equivalent to a simple eye that just detects light levels. That can't be used to create a usable image. I suspect they have something like an insectoid compound eye going on.
The article doesn't discuss how this will be implemented. Are they taking overhead shots of Fukushima to see where there is still leakage? I am not a radiation expert, but I don't understand how this would be more effective than a geiger counter. If anybody has any insight I would gladly read a response or any links to some more information.
Koalas. They're telepathic. Plus, they control the weather. -Margaret
Detecting gamma rays on a flat sensor is one thing. But how do you actually image gamma rays? You cannot use a lens or curved mirror. A cursory check on google/Wikipedia does not answer this. I can only think of a pinhole camera, which is very inefficient and would have to deal with radiation passing through the supposedly opaque walls.
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Scintigraphy is not only used for mere detection, but is in routine clinical use for imaging. You can go the pinhole route, but usually go with a movable collimator and movable detector, scanning the image. Now, if those guys have something that can snap a picture just like an optical camera, that would be interesting - but TFA is unfortunately silent on the details.
Ubi solitudinem faciunt, pacem appellant.
Property of these crystal detectors is that they give you zero directional information, essential in a device named 'camera' I'd say. The geometry of the casing helps you slightly, but I suppose the JAXA folks figured out an altogether new way of imaging.
Yeah, the detector is non-directional. That's why you use a collimator and scan the object by moving the collimator and the camera. Leads to long exposure times and an unwieldy mechanical setup - I'd be interested if they solved it differently, too. They did leave out the interesting parts in TFA, though.
Ubi solitudinem faciunt, pacem appellant.
... I am more suprised by the fact that they made a camera that can "see" at all. Mine doesn't, it just stores digitized pictures on a memory card.
My brother helped develop a pinhole scintillation camera in conjunction with Bendix in Ann Arbor in 1971. First application was thyroid imaging. Exposure times were rather long. They were also working on tomography software... on a PDP-11.
The Japanese are being resourceful and inventive in the face of horrible circumstances, and have come up with something great.
I am, however, still curious what necessitated the invention of certain TV game shows, the "chewing chewing chewing" song, and anime tentacle monsters.
Village idiot in some extremely smart villages.
As far as I know, the pinhole technique never made a breakthrough. Epic part of one's biography, though - especially coding image reconstruction on a PDP-11. That's hacking for real men, isn't it?
Ubi solitudinem faciunt, pacem appellant.
On one picture you can see how the visual image and the gamma radiation agree at the corner of a wall. You can see that the radiation spot turns 90 degrees with the bottom edge of the wall and how the radioactive materials kind of puddled near the bottom of the wall. It's cool to see that the two images agree.
Also there is video of the actual camera which is pretty big and not so portable. You probably want to keep it in a car most of the time.
http://www.japanprobe.com/2012/03/30/camera-can-see-radiation/
One more sensor to add....
---- Booth was a patriot ----
But it isn't! They should be using coroplast!
The big difference is that a scintillator or geiger tube is equivalent to a simple eye that just detects light levels. That can't be used to create a usable image. I suspect they have something like an insectoid compound eye going on.
Or just put a lead collimator in front of a scintillator film on top of a CCD. Bingo, instant gamma camera. I've been doing this for years for SPECT imaging.
If you want a vision of the future, imagine a youtube comments section scrolling - forever.
The English article edited out some information that was in the Japanese article.
Currently it doesn't tell you the precise amount of radiation being emitted but you get an idea of the highs and lows from it.
The technology that was developed for a detector installed in Japan's next-generation astronomical observatory satellite, the Astro H, to observe gamma ray bursts caused by astronomical events such as old stars exploding into supernovae. JAXA's Professor Tadayuki Takahashi who developed it says, "I want to aim at making this a practical tool quickly." And here is the Prof. Takahashi's cool page and Japanese version which shows news items too.
You will find several English papers on his work by Google: "High-Resolution CdTe Detectors and Application to Gamma-Ray Imaging"
Finally there are links from the Japanese page to a lot of detailed info about the gamma ray camera, though in Japanese there are PDFs including with photos of the supermarket experiment: here,pdf 1. pdf2, here.
If this becomes commercially available... and if Cavendish survives that long
Did you know that "FTW" ("for the win") is a direct translation of "Sieg Heil"?
Sounds like an April Fools joke a day early for many of us.