Catseye Single Alignment Pattern (CE-S)
|Name & ID||Symbol||Typical Target Used||DOF and Sensitivity||Description|
|Catseye Single (CE-S)||UUT Surface||Coarse (visual) to fine interferometric alignment of dZ||A single pattern is focused on the UUT optical surface. The central ray of this pattern must arrive normal to the UUT surface.|
Catseye Single (CE-S) alignment patterns send a focused beam of light such that the central ray arrives normal to the reference target.
Power fringes of the CE-S pattern indicate dZ misalignment
Due to the required ray path, CE-S patterns targeting the UUT often obscure some of the Null pattern.
This pattern is recommended to use if:
- UUT is significantly oversized and Null pattern does not need to fill FA of UUT.
- Missing regions of UUT surface map can be tolerated from Null pattern or UUT can be clocked and combine multiple measurements together to capture full surface.