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Registered Member #1143
Joined: Sun Nov 25 2007, 04:55PM
Location: Vilnius, Lithuania
Posts: 721
Anders M. wrote ...
Ok, if you're interested, I can give you a tip to get higher resolution x-rays. Resolution like this example should be possible with your x-ray generator.
i tried to to the same, and i was amazed by quality of picture ( but, my IR2153 keep dieing after 30s of hard work, i don't know why, ( i am using 8nF Cgs 40A mosfet's, and 5R resistor with diode, now i will use IRFP460A it has 3x lower Cgs and higher speed too, also i will add some zener's at gate ( around 18V) And that was just 34s at around 300W and 1m distance from tube, so picture still need some exposition (like 2x longer) i was able to see all fibers in microchips etc...
Hey, i was able to see in atomic level ( crystallography ) soon i will upload picture :) and here it is :)
And it is perfect crystal diffraction pattern, just guess where i get it ? yes from semiconductor. i was able to remove nice peace from power mosfet, after cleaning top and bottom i get nice looking peace of ideal silicon crystal
and here is my Wlan Router D-link
again, quality in real world is better, but scanner can't take all this quality into jpg and it is without intensifying screen, direct 2min exposure at ~120W
Registered Member #1143
Joined: Sun Nov 25 2007, 04:55PM
Location: Vilnius, Lithuania
Posts: 721
radhoo wrote ...
radhoo wrote ...
I would need to buy some, is there a good source you can recommand?
any idea?
i know man who selling it, buts is not online, you can get i from me (closed fabric, so they sell all parts for low price, and they have lot of thees diodes,)
Registered Member #3429
Joined: Sun Nov 21 2010, 02:04AM
Location: Minnesota, USA
Posts: 288
Linas wrote ...
my notebook. at 2s exp time
Nice job, and great looking radiographs! I was wondering how you mounted the X-ray tube. Is it imersed in oil? Also, did you filter the beam with aluminum?
Registered Member #1143
Joined: Sun Nov 25 2007, 04:55PM
Location: Vilnius, Lithuania
Posts: 721
Xray wrote ...
Nice job, and great looking radiographs! I was wondering how you mounted the X-ray tube. Is it immersed in oil? Also, did you filter the beam with aluminum?
yes, tube is in oil, not much, bat i can feel than tube start to warm up. Is aluminum filtering is any good ? ( how much impact it will have to picture quality ? )
Registered Member #3429
Joined: Sun Nov 21 2010, 02:04AM
Location: Minnesota, USA
Posts: 288
Linas wrote ...
yes, tube is in oil, not much, bat i can feel than tube start to warm up. Is aluminum filtering is any good ? ( how much impact it will have to picture quality ? )
All X-ray heads that are used for X-raying living tissue (humans and animals) are required to have a specified thickness of aluminum (and/or copper, depending on KV) directly in the beam path, usually at the beam exit port. The filter attenuates the low-energy (non-penetrating) photons which do not aid in producing the image, but can burn the skin, resulting in cancer and other proplems. Since you are not X-raying living tissue (I assume that you are not licensed to do so) then your X-ray head does not need a filter.
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
Xray wrote ...
Linas wrote ...
yes, tube is in oil, not much, bat i can feel than tube start to warm up. Is aluminum filtering is any good ? ( how much impact it will have to picture quality ? )
All X-ray heads that are used for X-raying living tissue (humans and animals) are required to have a specified thickness of aluminum (and/or copper, depending on KV) directly in the beam path, usually at the beam exit port. The filter attenuates the low-energy (non-penetrating) photons which do not aid in producing the image, but can burn the skin, resulting in cancer and other proplems. Since you are not X-raying living tissue (I assume that you are not licensed to do so) then your X-ray head does not need a filter.
Spot on there, but let's not forget another important reason for filtering out low energy photons in everyday industrial image forming systems* - namely sharpness, contrast and fine detail resolution because:
Photoelectric scattering increases as impacting photon energy falls. The lower the incident X-ray energy, the more the beam will be scattered as it passes through the air, through the specimen, and so on.
Re-radiation of low energy X-rays can occur from any of the elements in the primary X-ray path - the metal tube housing for example. These photons can impact on the imaging device from any number of angles, degrading the integrity of the anode focal spot as a single point source..
Anti-scatter grids are sometimes used to improve image sharpness and contrast. These grids are effectively thousands of collimators in parallel, and absorb those photons that are not in line to make a (near) right-angle strike on the imaging device. (Imagine a honeycomb structure made from heavy metal alloys or laminates - people are always patenting improved designs aimed at reducing primary X-ray attenuation by the grid, which can reach 50% on a bad hair day.)
*There are, of course, both Low Energy and Very Low Energy X-ray imaging systems, but these are seldom seen outside the laboratory.
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Full-wave X-Ray generator
