Proceedings Article | 2 September 2010
KEYWORDS: Phase shifts, Head, Beam splitters, Polarization, Semiconductor lasers, Fiber lasers, Mirrors, Fiber coupled lasers, Ocean optics, Sensors
Brightness preservation requirements for ever brighter synchrotron radiation and free electron laser beamlines require
surface slope tolerances of x-ray optics on the order of 0.2 μrad, or better. Hence, the accuracy of dedicated surface slope
metrology must be 0.1 μrad, or even less. Achieving this level of measurement accuracy with the flagship instrument at
synchrotron radiation metrology laboratories, the Long Trace Profiler (LTP), requires all significant sources of
systematic, random, and instrumental drift errors to be identified, and reduced or eliminated. In this respect, the
performance of certain components of the Advanced Light Source LTP-II design [Kirschman, et al., Proc. SPIE, 7077,
70770A-12 (2008)] is analyzed, considering the principal justification for inclusion of each component, possible
systematic error due to the quality of its optical material, and drift effects due to generated heat, etc. We investigate the
effects of replacement of the existing diode laser with a fiber-coupled laser light source, and demonstrate that reducing
the number of components by using a single beam on the surface under test (SUT), rather than an original double beam
maintains, or even improves the accuracy of measurement with our LTP. Based on the performance of the upgraded
LTP, we trace the further steps for improving of the LTP optical system.
