Re: [Phys-l] pinhole camera

[John Denker <jsd@av8n.com>]

On 04/15/2007 05:32 PM, Ludwik Kowalski wrote:
> Here is an application in which a pinhole camera can be used today. (I 
> do not remember where I read about this, years ago.) Suppose you want 
> to know about distribution of X rays at the surface from which they are 
> emitted. A lead sheet with a pinhole, plus an X-ray film, is a 
> solution. The film will produce "the image" of the source. Yes, a lens 
> focusing X-rays, if it existed, would be desirable.


Fresnel zone plates for focusing Xrays have been around for
many years.

For example:
  S. J. Spector, C. J. Jacobsen, D. M. Tennant,
  "Process optimization for production of sub-20 nm soft x-ray zone plates"
  http://xray1.physics.sunysb.edu/~micros/publications/papers/spector_jvstb_1997.pdf

They are a royal pain to make, but they work a lot better than
pinhole cameras.