[Linas] built himself an x-ray generator for a scholarship contest. We assume this wasn’t enough of a challenge for [Linas] because after the x-ray generator was done, he used his project to model objects in 3D (Google Translate link). It’s an amazing build, leaving us feeling sorry for the guy that came in second place to the home-made CT scanner.
The theory behind a CT scanner is fairly simple – take a series of x-rays of an object around an axis of rotation. From there, it’s a fairly simple matter to digitize the x-ray images to produce a 3D model. The hard part is building the x-ray generator. [Linas] used directional x-ray tubes, a few power supplies and from what we can gather x-ray film instead of a CCD sensor. The film was scanned into a computer and reassembled to get a 3D image.
[Linas] doesn’t seem too keen on giving away the schematics for his build to any old joker on the Internet because of the high voltage and radiation components of his build. Still, it’s an amazing build.
Check out the YouTube demo of [Linas]’s CT scanner imaging an old computer mouse and a reconstruction of the same data done in MATLAB after the break.
[youtube=http://www.youtube.com/watch?v=78M8du7o4iQ&w=470]
[youtube=http://www.youtube.com/watch?v=u5n6oSAmaGs&w=470]
Wow, just wow!
That about sums it up for me too.
Meh… He couldn’t manage an FMRI machine?
I kid! I kid! Unbelievable!
While this is (barely) Computed Tomography (he’s taking a series of images, computing the structure of the object…and then producing slices, which is the tomography part)…
…it’s not, by any means, a “scanner”.
The second video looked like the pretty lights that windows media player shows when it plays music.
I don’t think this is a CT scanner as in inverse radon transform/ backprojection? It’s just taking directional xrays? still very cool.
It sure as hell looks like backprojection to me. Rather unfiltered backprojection, too, especially with the resolution he seems to have achieved with the film.
The working principle described is also known as ‘cone beam CT’. This principle is used in many commercially available industrial CT scanners. See e.g.
http://www.ge-mcs.com/en/phoenix-xray/
What’s the maximum size of an object it can image?
Something like this could be very useful for inspecting BGA components, might even open them up for use in hackerspaces.
Can you not source x-rays from a cathode-ray tube, or is that just Michael Weston bullshit? :)
If the voltage is high enough, yes.
http://www.epa.gov/radtown/tv-computer.html
It’s far easier to scavenge an xray tube from a used dental xray head. You even get the high voltage transformer and necessary circuits in a complete, tidy package.
You can, but you have to remove the leaded front glass, replace it with something transparent to x-rays, redo the vacuum, and use a higher voltage power supply. I think there are some vacuum tube amplifiers which happen to work very well as x-ray generators though.
Incredible work. Sadly- the lethality of such power densities and the DISTANCE such radiation can be dangerous at precludes anyone publishing complete plans.
Perhaps if there were a sane tort environment or that lawyers did not view an accident victim as the Golden Ticket? That’s my “Social Hack” for today :>
The technical path to examine for advancements might be found by looking for “Lixiscope” technology
Hey, that’s my project, i am famous :)
right now making improved version with better control and lot of other things :)
congratulations on an amazing project mate
Absolutely fabulous work!
http://www.noah.org/science/x-ray/stong/
DIY Big bulky archaic x-ray emitter
http://www.crtsite.com/page5.html
Breif history of CR/X-ray tubes
cool
ok … I am deeply impressed
Impressive yes, but I damn well hope nobody in my immediate area is going to try to make one in his home.
don’t worry. x-ray source works like flash light. it creates beam of light in one direction, and you just point it to concrete wall in basement, all other rays are captured by shielding, and just some change path because of Rayleigh scattering
just 2mm of lead can protect from 120KeV light
Linas,
Can anyone source 2MM lead sheeting for those about to make this?
Please include a link to the lead sheeting for the boys and girls.
Scary cool what dedicated hackers can get done.
because I am studying in Vilnius University Faculty of Physics some of professor was concern about safety, so they supply me with lead, cadmium and wolfram sheets for making sandwich shield for x-ray tube.
Also i have personal dosimeter, so i don’t worry too much
more about this project:
http://4hv.org/e107_plugins/forum/forum_viewtopic.php?116086
As an employee of a company that makes CT scanners, I’m enjoying both the drooling and the slapping going on in this thread.
We have the greatest equipment and the best software.
We also have the crappiest CEO (he’s in obama’s silly and mythical “Jobs” cabinet) as well as the sales division. We expect more layoffs soon.
Linas, if you need people to start your own company with, there’s a lot of people out here that will be available soon. I wont say the name of the company, but we’re probably big competitors with “SPECIFIC Electric”. lol.
kanchoblindside – how to contact you to get started. I am interested in building a CT machine manufacturing….and this is for real.
I have plans to make a homemade PET scanner using the radiation from 40K.
Seems that this might work with very long exposure times as tested using my modified SBM20 and also with the ZP1310 (de-filtered ZP1313/4)
Trouble is getting that many tubes is awfully expensive but worth it.
Additional: The experiments so far suggest that 40K can indeed be used. I did get some problems but easily resolved.
For various reasons smaller tubes may be better here so SBM-21 though not that sensitive is adequate at the interesting gamma range (300-513keV) and can also be used for monitoring TGF events.
An event that causes many or all of the tubes to pulse at nearly the same time is likely to be significant.