System and method for switching position signals during servo control of a device table
US6801300B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 14, 2001 |
| Grant date | Oct 5, 2004 |
| Priority date | — |
| Expiry date | Aug 14, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70725
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A stage assembly (10) for moving a device (26) along an X axis and a Y axis includes a stage base (12), a device table (16), a stage mover assembly (18), a measurement system (21), and a control system (22). The stage mover assembly (18) includes a pair X guide movers (82) (84) and a Y table mover (87). The measurement system (21) includes a first X system (100) and a second X system (102). The control system (22) receives the position signals from the measurement system (21) and directs current to the X movers (82) (84) to move the device table along the X axis. The control system (22) can be designed to not skip any servo cycles during switching of position signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.