Our 1.5LTE-1000MM Low Thermal Expansion Length Reference Bar provides a stable length for use during laser tracker or scanner jobs. Its unique design uses specially designed end caps which counteract length changes in the bar due to thermal growth. This provides a virtually constant length through a wide working temperature range. Testing has shown that the 1.5LTE-1000MM has a thermal stability 40% better than invar.
The target holders on each end are positioned off-axis, and allow 360° rotation of the SMR, adding application flexibility. You can place the reference bar in relevant positions in the measurement volume for scaling, consistency, and stability checks during a job. Or, you can align the bar with your tracker's beam, and use the interferometer alone to compare against the bar's length (with no Az or El encoder contributions to error).