Moving member mechanism and control method therefor
AssigneeCanon Kabushiki Kaisha
InventorTosiya Asano
Life of this patent
Estimating the term…
Abstract
This invention relates to a moving member mechanism including an electromagnet having a coil for driving a moving member and an amplifier which supplies a current to the coil. The first control mechanism which feedback-controls the electromagnet on the basis of command information input to the input portion sets a current supplied from the amplifier to the coil to 0 when the command information represents 0.
Claims14
A moving member mechanism comprising:
- an electromagnet having a coil for driving a moving member;
- a first control mechanism which has an input portion and feedback-controls the electromagnet on the basis of command information input to the input portion, wherein the first control mechanism includes an amplifier which supplies a current to the coil;
- and
- an offset compensation mechanism which sets the current supplied from the amplifier to the coil to 0 when the command information represents 0.
An exposure apparatus comprising:
- an optical system which projects exposure light incident on a mask bearing a pattern onto a substrate;
- and
- a stage apparatus which holds and aligns the substrate or the mask,
- the stage apparatus including:
- an electromagnet having a coil for driving the substrate or the mask;
- a first control mechanism which has an input portion and feedback-controls the electromagnet on the basis of command information input to the input portion, wherein the first control mechanism includes an amplifier which supplies a current to the coil;
- and an offset compensation mechanism which sets the current supplied from the amplifier to the coil to 0 when the command information represents 0.
A method of controlling a moving member mechanism including an electromagnet having a coil for driving a moving member and an amplifier which supplies a current to the coil, comprising:
- a control step of feedback-controlling the electromagnet on the basis of input command information;
- and
- an offset compensation step of setting a current supplied from the amplifier to the coil to 0 when the command information represents 0.
Dependencies are inferred from the claim text.