Crosshair Point Focus (PF-X)
|Name & ID||Symbol||Typical Target Used||DOF and Sensitivity||Description|
|Crosshair Point Focus (PF-X)||Reflective Tooling Ball||Coarse (visual) to mid-range interferometric alignment of dX, dY, dZ||Projects a focused spot to vertex of a reflective tooling ball. These patterns also utilize a crosshair to provide visual lateral alignment feedback.|
Crosshair point focus PF-X alignment patterns work by bringing light to focus on the surface of a (generally) curved alignment target, such as a reflective tooling ball.
Decenter misalignment of a PF-X pattern leads to displacement of the return beam in that direction.
To aid in aligning the displaced beam, AOM adds an opaque crosshair mark on top of the focusing pattern.
The video below shows the lateral alignment process of a PF-X pattern as viewed by an interferometer.
Spacing (Z) misalignment shows up in PF-X patterns as power fringes.