Patent ID: 8416392

Claim:
An optical imaging arrangement comprising: a mask unit adapted to receive a pattern, a substrate unit adapted to receive a substrate; an optical projection unit comprising a group of optical element units comprising first and second optical element units, the optical projection unit being adapted to transfer an image of the pattern onto the substrate; a first imaging arrangement component, the first imaging arrangement component being a component of the first optical element unit, a second imaging arrangement component, the second imaging arrangement component being different from the first imaging arrangement component and the second imaging component being a component of the second optical element unit; a metrology arrangement; the metrology arrangement configured to capture a spatial relationship between the first imaging arrangement component and the second imaging arrangement component; the metrology arrangement comprising a reference structure; the metrology arrangement configured to capture a first spatial relationship between the first imaging arrangement component and the reference structure; the metrology arrangement configured to capture a second spatial relationship between the second imaging arrangement component and the reference structure; and the metrology arrangement configured to use the first and second spatial relationships to determine a spatial relationship between the first imaging arrangement component and the second imaging arrangement component.