More about compound refractive #lenses for #X-rays.
on 02015-08-12Whoa, you can focus #X-rays up to 40 kEv with a series of concave #lenses made of aluminum or beryllium (negative refractive index!), like, say, a block of aluminum with a series of holes drilled in it, or a series of prisms (“saw-tooth lens”; not sure this isn’t just a Fresnel) of silicon, plastic, or lithium. If stimulated or induced gamma emission from metastable nuclear isomers (like they were trying to do with #hafnium) is possible at all, this might be the way to do it.
on 02015-08-12A tech note from cylindrical-lens manufacturer Newport: circularizing the beam from a #laser diode with two cylindrical #lenses with different focal lengths and perpendicular axes, since laser diodes have elliptical divergence. Why has nobody done this for regular magnification? Cylindrical lenses are dramatically easier to manufacture than spherical lenses! There must be a reason it won’t work.
on 02015-08-12