This focussing effect is very strong with WAVELENGTHs less than the aperture of the reflector, making it particularly suitable for recording high frequency sounds such as birdsong. Schematic diagram ...

Parabolic reflectors are pretty handy devices ... But a big, shiny mirror for your solar death-ray needs is another matter, which is where this pressure-formed space blanket mirror might come ...

To me, this means a large parabolic reflector, a feed horn made of brass ... the best I could ever hope for is a very low-resolution image of the galactic plane. If I get lucky, there might ...