Displacement measurement system and sheet feed system incorporating the same

This invention relates to displacement measurement systems and sheet feed systems incorporating the same. A displacement measurement system and a sheet feed system incorporating the same are described. The displacement measurement system includes a support arm, a roller, and an optical encoder. The support arm has a first end and a second end and is configured to turn about a pivot axis on a pivot located closer to the first end than the second end so that displacement of the first end causes a greater corresponding displacement of the second end. The roller is mounted at the first end of the support arm and is configured to rotate about a roller axis substantially parallel to the pivot axis. The optical encoder has at least one component mounted at the second end of the support arm and is configured to generate signals responsive to movement of the second end of the support arm.