Abstract: An optical encoding apparatus for the detection of position and/or motion of a mechanical device includes a codescale, an encoder housing having one or more portions and a light-detecting sensor embedded within the encoder housing, wherein the light-detecting sensor is capable of sensing a pattern produced by the codescale superimposed on the light-detecting sensor, and wherein the light-detecting sensor includes a two-dimensional array of light detection elements having dimensions n-by-m where n and m are both integers greater than 4.

Abstract: An encoder having a code pattern on a carrier and an emitter detector module is disclosed. The code pattern includes alternating reflective and opaque regions on a carrier that includes a planar surface. The emitter-detector module includes a light source that generates light and directs a portion of the generated light at the first side of the carrier and a first detector that detects light reflected from one of the reflective regions. The reflective regions include a three-dimensional element for directing light from the light source onto the first detector. The element has a surface that is inclined at an oblique angle with respect to the planar surface. The code pattern moves with respect to the emitter-detector module. The three-dimensional element can include a reflective imaging element that images the light source onto a surface of the first detector.

Abstract: An optical encoder system is disclosed with a single pattern medium having a first coded pattern disposed on the first side, a second coded pattern disposed on the second side, a first optical encoder disposed toward the first side, and a second optical encoder disposed toward the second side. An optical encoder device is disclosed with a first coded pattern disposed on the first side, and a second coded pattern disposed on the second side. There is disclosed a method for using an optical encoder device to obtain information related to a motor which includes the steps of illuminating a first coded pattern disposed on a first side of a pattern medium, illuminating a second coded pattern disposed on a second side of the pattern medium, detecting light reflected from the first side, detecting light reflected from the second side, and analyzing the reflected light.

Abstract: An encoder having a code strip, a light emitter, a photodetector, and a spacing member is disclosed. The code strip includes an encoding region having a plurality of reflective and absorptive regions on a carrier having an encoding surface. The light emitter generates a light signal that is reflected from one of the reflective regions. The reflected light is measured by the photodetector. The spacing member maintains a fixed distance between the encoding surface and the photodetector when the code strip moves relative to the photodetector in a travel direction. The spacing member is attached to the photodetector and moves relative to the code strip when the code strip moves relative to the photodetector. A mechanism for allowing one of the photodetector and the code strip to move in a direction perpendicular to the travel direction to accommodate alignment errors can also be included.