What is a zone plate?
Zone-plate photography is a lenless technique similar to pinhole photography. Instead of a small hole, however, we use a circular pattern consisting of transparent and opaque rings. The diameter of each ring is individually calibrated. It is an old idea drawing upon calculations akin to those used for Fresnel lenses. German scientists discovered that zone plates can be used to focus third-generation gamma-ray lasers (where normal glass lenses are useless) … and we can use them to produce pictures!
It looks like this (enlarged image)
Zone-plate photographs feature unusual, yet beautiful effects. They are slightly blurred, lacking in fine detail and show strange 'halo effects' around light objects.
Zone Plates can be made using online calculators such as Whizkidtech (http://www.whizkidtech.redprince.net/zoneplate/ ) or the downloadable freeware Pinhole Designer. Unfortunately, Whizkidtech zone plates generate errors at high resolutions (See photograph below). Pinhole Designer is the better program. If you have access to a computer-to-film (CTF) processor, you print your own zone plates. Ready-to-go zone plate sets are also available for purchase.
Below you can see sample of zone plate effects ( short movie by Amadeusz Andrzejewski)
The patterns of zone plate can be also much more coplicated:
this is so called photon sieve (enlarged)- effects are similar to "ordinary" zone plate
...and sample below