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AssigneeAsm Technology Singapore Pte Ltd
InventorsGary Peter Widdowson, Sun Kuen Wong, Ajit Gaunekar
Estimating the term…
The position of a working point relative to a working space, such as a working point of a carriage on a gantry beam of an XY positioning table, is determined by measuring at least two sets of displacements. A first set of displacements, of the working point relative to an intermediate component, such as the gantry beam, includes a relatively large displacement (X) in a first linear degree of freedom and relatively small displacements (Y1′, Y2′), in at least two of the five degrees of freedom other than the first. The second set of displacements, of the intermediate component relative to the working space, includes a relatively large displacement (Y1, Y2), in a second linear degree of freedom, and relatively small displacements (X1′, X2′), in at least two of the five degrees of freedom other than the second.
A position measurement system for determining the position of a working point (8) relative to a working space (9), the position measurement system including at least first and second measurement modules, the first measurement module being capable of providing measurements of a first set of displacements of the working point relative to an intermediate component (3), the first set of measured displacements including a relatively large displacement (X) in a first linear degree of freedom and relatively small displacements (Y1′, Y2′) in at least two of the five degrees of freedom other than the first, the second measurement module being capable of providing measurements of a second set of displacements of the intermediate component relative to the working space, the second set of measured displacements including a relatively large displacement (Y1) in a second linear degree of freedom, the second degree of freedom being different from the first, the second set of measured displacements also including relatively small displacements (X1, X2) in at least two of the five degrees of freedom other than the second.
A method of determining the position of a working point relative to a working space, including measuring a first set of displacements of the working point relative to an intermediate component, the first set of measured displacements including a relatively large displacement in a first linear degree of freedom and relatively small displacements in at least two of the five degrees of freedom other than the first, measuring a second set of displacements of the intermediate component relative to the working space, the second set of measured displacements including a relatively large displacement in a second linear degree of freedom, the second degree of freedom being different from the first, the second set of measured displacements also including relatively small displacements in at least two of the five degrees of freedom other than the second, and determining the position of the working point relative to the working space from the displacements of the first and second sets.
Dependencies are inferred from the claim text.