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.
An optical motion encoder for translation of movement information into a digital output. The optical encoder includes an optical member having a parabolic reflecting surface and a planar surface with a code pattern printed thereon. The light rays received by the parabolic reflecting surface from a light source positioned on the axis of symmetry of the parabolic reflecting surface are reflected as parallel light rays through the planar surface to be modulated by the code pattern and detected by a light detector. In this way, both, the collimator and the code wheel or code strip of prior art optical encoders are represented by a single optical member.
An optical motion encoder for translation of movement information into a digital output. The optical encoder includes an optical member having a parabolic reflecting surface and a planar surface with a code pattern printed thereon. The light rays received by the parabolic reflecting surface from a light source positioned on the axis of symmetry of the parabolic reflecting surface are reflected as parallel light rays through the planar surface to be modulated by the code pattern and detected by a light detector. In this way, both, the collimator and the code wheel or code strip of prior art optical encoders are represented by a single optical member.