Patent ID: 6054784
Filing Date: 2000-04-25
Classification: G03F,Y10T

Abstract:
A positioning device comprising:a first part;a second part comprising an object holder for retaining a substantially disc-shaped object in a position parallel to an X-direction and parallel to a Y-direction which is perpendicular to the X-direction; andthree Lorentz motors constructed and arranged such that said second part is displaceable with respect to said first part parallel to said X-direction and parallel to said Y-direction and is rotatable about an axis of rotation which is parallel to a Z-direction which is perpendicular to said X-direction and perpendicular to said Y-direction,each of said motors being provided with a permanent magnet system connected with one of said first part and said second part and an electric coil system which cooperates with said magnet system and is connected with the other of said first part and said second part, said motors hence providing a Lorentz force coupling between said first part and said second part,said electric coil system of each of said motors being provided with at least one electric coil with windings which extend substantially parallel to a main axis of the coil system, said main axis of the coil system big perpendicular to said Z-direction,said main axis of said coil system of each of said three motors enclosing an angle of substantially 120.degree. with said main axis of said coil system of each of the two other motors.