The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 25, 2006
Filed:
Feb. 09, 2004
Pai Hsueh Yang, Palo Alto, CA (US);
Tim Teng, Fremont, CA (US);
Kazuhiro Hirano, Saitama, JP;
Bausan Yuan, San Jose, CA (US);
Pai Hsueh Yang, Palo Alto, CA (US);
Tim Teng, Fremont, CA (US);
Kazuhiro Hirano, Saitama, JP;
Bausan Yuan, San Jose, CA (US);
Nikon Corporation, , JP;
Abstract
A stage assembly () for moving a device () includes a stage (), an attraction-only type actuator pair () that moves the stage (), and a control system (). In one embodiment, the actuator pair () includes a first electromagnet (F), a first conductor (F) and a first target (F) having a first target surface (F). The actuator pair also includes a second electromagnet (S), a second conductor (S) and a second target (S) having a second target surface (S). The first electromagnet (F) is positioned at a first angle θrelative to a first target surface (F) and the second electromagnet (S) is positioned at a second angle θrelative to the second target surface (S). The control system () directs a first current to one or more of the electromagnets based on at least one of the angles θ, θ. Further, one or more electromagnets () can include a first measurement point and a second measurement point. The control system () can direct current to the actuator pair () based on the relative distance between the first and second measurement points and the corresponding target surface ().