US Patent 7299991 Reflective members for use in encoder systems

Reflective members for use in encoder systems are provided. One embodiment comprises a reflective member comprising a reflective layer, at least another layer, and a reflective pattern comprising a first portion having a first reflective property and a second portion having a different reflective property. The reflective layer forms at least a part of the reflective pattern. In addition, the aforementioned first portion of the reflective member has a width of less than half of the grating period. The reflective member enables measurement of at least one operational attribute of an object.