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cronxeh
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What are the current technical difficulties that prevent us from focusing x-rays with lenses?
chroot said:I'm not talking about diffraction; I'm talking focusing X-rays, i.e. bringing them a focus. This can be done with glancing reflections from plane mirrors.
- Warren
Oops! Chroot got there first!cronxeh said:So on a smaller angle the material does not absorb the waves?
cronxeh said:I see. So suppose there was a material that had 100% reflective rate for EHF EM waves. What would be the emerging technologies (other than microscopes, high energy weapon systems, etc)?
cronxeh said:I see. So suppose there was a material that had 100% reflective rate for EHF EM waves. What would be the emerging technologies (other than microscopes, high energy weapon systems, etc)?
I think that's a bit off. My research on the subject seems to suggest that the rods were the lasers, and that the bomb was the energy pump - hence the common name "bomb pumped x-ray laser". There was no means to focus the laser, or even prevent it from firing both forwards and backwards.GENIERE said:I recall the 1980's star war program envisioned an a-bomb generating x-rays that used a large number of cylindrical tubes in a bundle to focus the beam.
Yep.GENIERE said:I recall the 1980's star war program envisioned an a-bomb generating x-rays that used a large number of cylindrical tubes in a bundle to focus the beam.
Actually GENIERE is correct - that was one concept, and the term was "nuclear pumped X-ray laser". One could also use a specially designed nuclear reactor, which offers a more stability, at the cost of power density.SciFiGuy said:I think that's a bit off. My research on the subject seems to suggest that the rods were the lasers, and that the bomb was the energy pump - hence the common name "bomb pumped x-ray laser". There was no means to focus the laser, or even prevent it from firing both forwards and backwards.
you can find a theoretical tabulation of the 'mass-absorption coefficient' of every element between hydrogen and Uranium for X-ray energies in this link. My PhD project involves measuring some of these X-ray absorption coefficients, and the tabulation is pretty accurate.cronxeh said:No seriously is there any reason why a material could not be 100% reflective to x-rays on a molecular level?
Hmm...so does that mean that nukes produce coherent light?Astonuc said:The problem is nuclear 'bombs' is that the energy burst is more or less isotropic (not to mention very destructive, and otherwise destabilizing), and once would catch only part of the nuclear energy. The energy, primarily gamma and X-ray radiation can be focussed (somewhat) using tubular metal structures, and the photons primarily 'go in one end and out the other'.
Lenses focus X-rays through a process known as refraction. When X-rays pass through a lens, they are bent and redirected towards a focal point, resulting in a concentrated beam of X-rays.
There are two main types of lenses used to focus X-rays: Fresnel zone plates and compound refractive lenses. Fresnel zone plates use a series of concentric rings to diffract and focus X-rays, while compound refractive lenses use multiple small lenses to bend X-rays towards a focal point.
Yes, X-rays can be focused to a single point using specialized lenses and techniques. However, the size and shape of the focal point may vary depending on the properties of the lens and the wavelength of the X-rays.
Focusing X-rays allows for more precise imaging and analysis of objects and materials. It can also increase the intensity of the X-ray beam, making it easier to detect and measure small or low-contrast features.
There are limitations to focusing X-rays with lenses, such as the inability to focus certain wavelengths and the potential for lens damage due to the high energy of X-rays. Additionally, the size and shape of the focal point may limit the resolution and accuracy of the resulting images.