Static-wavelength independent radiation attenuator.

The static radiation attenuator consists of one or several layers of absorbing material into which randomly distributed holes are drilled. The attenuator needs no moving parts and reduces not only the time averaged but also the instantaneous brightness, and reduction by an arbitrarily large factor can be easily achieved. The transmitted intensity fluctuates randomly as a function of spatial position, but the expected fluctuation can be evaluated and can be made arbitrarily small. Various properties of the device are explored.