  We present a method for determining the 3D intensity distribution of directed
laser radiation with micrometer resolution in restricted volumes. Our method is
based on in-coupling and guiding properties of optical fibers, with the current
version requiring only few hundred micrometers. We characterize the performance
of the method and experimentally demonstrate profiling of micrometer sized
laser beams. We discuss the limiting factors and routes towards a further
increase of the resolution and beam profiling in even more restricted volumes.
Finally, as an application example, we present profiling of laser beams inside
a micro ion trap with integrated optical fibers.
