Patent ID: 6822733
Filing Date: 2004-11-23
Classification: G01B,G01C,G01D

Abstract:
An optical system for laser encoder resolution extension with three-dimensional motion decoupling capability comprising:a moving target; said moving target having three-dimensional linear motion freedom; a fixed base positioned laterally spaced apart in an X direction from said moving target; a single first prism mounted on said moving target, a plurality of prisms, a retroreflector, a laser source, and a detector mounted on said fixed base; said single first prism being larger than said plurality of prisms; a three-dimensional optical path defined by said first prism, said plurality of prisms, and said retroreflector for reflecting a laser beam from said laser source to said detector with said laser beam being reflected multiple times between said single first prism and each of said plurality of prisms; said three-dimensional optical path providing multiple times optical resolution extension power for linear displacement measurement and encoding; said optical system being sensitive to a motion of said moving target in said X direction and being substantially unaffected by movement in a Y direction and a Z direction.