Abstract: An optical encoder includes a code strip having a first side, a second side, a first track comprising indicia thereon, and a second track comprising indicia thereon. The code strip is moveable along a displacement path with respect to the optical encoder. A light source positioned on the first side of the code strip directs light toward the code strip. A first detector element is positioned on the second side of the code strip and is generally aligned with the first track of the code strip. A second detector element is positioned on the second side of the code strip and is generally aligned with the second track of the code strip. The second detector element is also positioned so that the second detector element is located a spaced distance along the displacement path from the first detector element.

Abstract: An optical encoder includes an encoder pattern having (i) an A/B pattern of first areas and second areas alternating in a first direction, wherein the first areas have a different optical transmissivity or reflectivity than the second areas, and (ii) an index pattern disposed adjacent the A/B pattern in the first direction.

Abstract: An optical encoder includes a code strip having a first side, a second side, a first track comprising indicia thereon, and a second track comprising indicia thereon. The code strip is moveable along a displacement path with respect to the optical encoder. A light source positioned on the first side of the code strip directs light toward the code strip. A first detector element is positioned on the second side of the code strip and is generally aligned with the first track of the code strip. A second detector element is positioned on the second side of the code strip and is generally aligned with the second track of the code strip. The second detector element is also positioned so that the second detector element is located a spaced distance along the displacement path from the first detector element.

Abstract: An encoder for measuring the position of a rotating shaft is disclosed. The encoder includes a drum having an encoding track thereon and a detector module having a light source and a photodetector. The drum includes a cylindrical surface characterized by an axis, the drum having a surface with a normal perpendicular to the axis. The encoding track includes a plurality of alternating reflective and non-reflective stripes arranged on the cylindrical surface. The first light source illuminates the stripes at an opaque angle relative to the normal. The first photodetector is positioned to receive light from the light source that is reflected from the reflective stripes when the drum moves relative to the photodetector. In one embodiment, the drum rotates about the axis when the shaft rotates. The encoding track can be either on the inside or outside of the drum.

Abstract: An optical encoder includes a code strip having a first side, a second side, a first track comprising indicia thereon, and a second track comprising indicia thereon. The code strip is moveable along a displacement path with respect to the optical encoder. A light source positioned on the first side of the code strip directs light toward the code strip. A first detector element is positioned on the second side of the code strip and is generally aligned with the first track of the code strip. A second detector element is positioned on the second side of the code strip and is generally aligned with the second track of the code strip. The second detector element is also positioned so that the second detector element is located a spaced distance along the displacement path from the first detector element.

Abstract: An optical encoder includes an encoder pattern having (i) an A/B pattern of first areas and second areas alternating in a first direction, wherein the first areas have a different optical transmissivity or reflectivity than the second areas, and (ii) an index pattern disposed adjacent the A/B pattern in the first direction.

Abstract: An optical encoder includes a code strip having a first side, a second side, a first track comprising indicia thereon, and a second track comprising indicia thereon. The code strip is moveable along a displacement path with respect to the optical encoder. A light source positioned on the first side of the code strip directs light toward the code strip. A first detector element is positioned on the second side of the code strip and is generally aligned with the first track of the code strip. A second detector element is positioned on the second side of the code strip and is generally aligned with the second track of the code strip. The second detector element is also positioned so that the second detector element is located a spaced distance along the displacement path from the first detector element.

Abstract: An encoder for measuring the position of a rotating shaft is disclosed. The encoder includes a drum having an encoding track thereon and a detector module having a light source and a photodetector. The drum includes a cylindrical surface characterized by an axis, the drum having a surface with a normal perpendicular to the axis. The encoding track includes a plurality of alternating reflective and non-reflective stripes arranged on the cylindrical surface. The first light source illuminates the stripes at an opaque angle relative to the normal. The first photodetector is positioned to receive light from the light source that is reflected from the reflective stripes when the drum moves relative to the photodetector. In one embodiment, the drum rotates about the axis when the shaft rotates. The encoding track can be either on the inside or outside of the drum.