The differential head is designed with a unique optical scheme to achieve a low SDE performance.  Integrated beam steerers allow for pitch and yaw adjustment during set up which improves the alignment process (only suitable for plane mirror applications).

The RLD10-X3-DI detector head has been designed to mount to the external wall of a process chamber via a simple three-pin mount. There is no need to enter the chamber to align the detector head – integral beam steerers allow independent pitch and yaw adjustment of reference and measurement beam – and the design of the mounting system allows the detector head to be removed and repositioned with minimal effect on system alignment.

Features and benefits

• Exceptional metrology -ppb frequency stability and ultra low cyclic error, allowing output resolutions to 38.6 pm.
• Differential configurations – measures the relative position of the stage relative to the column, therefore eliminating common mode errors such as motion of the chamber side wall associated with environmental fluctuations.
• Rapid alignment – simple alignment from outside the vacuum chamber using four integrated beam steerers to overcome chamber and mirror mounting tolerances.

Specification