Renishaw’s new multi-axis periscope (RMAP) is designed to enable six degrees of freedom measurements in XY stage applications, utilising the performance from the RLD10-X3-DI interferometer head, to accurately measure pitch, yaw and roll. Measuring angular deviations within the stage motion enables correction of these errors, within the machine motion, to improve positioning accuracy. Whilst these measurements can be achieved using independent differential interferometer heads, the multi-axis periscope minimises the beam footprint to 18 mm by 35 mm, allowing for smaller stage mirrors and lowering machine costs.
With an angular range of ±30 arc seconds, the multi-axis periscope is compatible with most high-performance stages, further optimising their performance. A single mounting face enables the multi-axis periscope to be installed quickly and easily to the vacuum chamber or metrology frame.
Using the RLD10-X3-DI head for angular measurements allows for errors generated from laser frequency variation and environmental changes to be common between the two paths. This improves the accuracy and repeatability compared to angular deviations calculated from two independent beams.
