Sub-m-rad angular stability measurements by use of long trace profiler based systems.... The optical method, using optics with an even number of reflecting surfaces (for example, a right angle prism, pentaprism, or rhomboid prism) to reduce the influence of existing angular displacement, is introduced and the comparison measurement is presented....
Alternate surface measurements for gmt primary mirror segments... The corroboration tests discussed in this paper are: • Direct surface profile using metrology system based on a laser tracker, measuring low order shape errors • Shear testing with full aperture interferometer, separating small scale errors in the null test from those in the mirror • Slope testing with scanning pentaprism, measuring low order shape errors and sampling small scale error
High accuracy alignment facility for the receiver and transmitter of the bepicolombo laser altimeter... We describe in detail the solution found to attenuate the high energy of the instrument laser transmitter by an original beam splitting pentaprism group....
A simple way of characterizing x-ray downwards-deflecting mirror-bender assemblies using the long trace profilerA simple device composed of a modular double-pentaprism system that enables the long trace profiler (LTP) to measure mirrors in nonconventional ways, i.e.,...
