Abstract: An interpolating detector for generating a position signal indicating a change in the relative position of a code pattern that includes alternating light and dark stripes is disclosed. The interpolating detector includes a photodiode array, an interpolation function generator, a detector function generator, and a cross-point detector. The photodiode array includes a plurality of sets of photodetectors that generate sinusoidal signals having different amplitudes and phases. The interpolation function generator generates first and second interpolation functions, I1(x)=f1 cos(x) and I2(x)=f2 sin(x), respectively, from the photodiode signals. The detector function generator generates 4 detector signals, D1(x)-D4(x), from the photodiode signals. The cross-point detector generates a transition signal when I1(x) crosses D1 or D3 or when I2(x) crosses D2 or D4.

Abstract: An encoder having a detector and an optical system that generates an image of a code strip on the detector is disclosed. The image includes a plurality of light and dark stripes, the detector generating a plurality of sinusoidal signals differing in phase from one another as the code strip moves relative to the detector. Each sinusoidal signal cycles through one period when the code strip moves a distance equal to one light stripe and one dark stripe with respect to the detector. A frequency multiplier generates a plurality of frequency multiplied signals. The encoder utilizes a signal interpolator that defines a plurality of position locations utilizing the frequency multiplied signals, there being at least 5 such points corresponding to the code strip moving a distance equal to one light stripe and one dark stripe with respect to the detector.

Abstract: An Enhanced Reflective Optical Encoder (“EROE”) having an emitter module for transmitting emitted optical radiation to an encoded media and a detector module for receiving reflected optical radiation from the encoded media. The EROE may include a transmissive layer covering both the emitter module and the detector module, and an optical isolation element located within the transmissive layer and located between the emitter module and the detector module. The optical isolation element reduces undesired optical radiation transmitted from the emitter module to the detector module, where the undesired optical radiation is a portion of the emitted optical radiation.

Abstract: A coding element such as a codewheel includes first and second surfaces that are configured with respect to each other and with respect to a light beam such that the light beam is reflected at the two surfaces using the optical phenomenon of total internal reflection. The coding element also includes a coding pattern that is aligned in an optical path of the light beam after the light beam has reflected off of both of the surfaces. A coding element with surfaces that reflect a light beam as a result of total internal reflection can be utilized in an encoding system that operates in transmission while the light source and the photodetector array are located on the same side of the coding element.

Abstract: A dual-axis optical encoder device is disclosed. The optical encoder includes a substrate having a first surface and a second surface opposite the first surface and a first optical encoder on the first surface of a substrate and a second optical encoder on the second surface of the substrate. Each optical encoder includes an optical emitter and an optical detector. The dual-axis optical encoder device provides, within a single device, the ability to acquire movement information on two different axes.

Abstract: An optical source includes an optical emitter with an encapsulant covering the optical emitter. A diffractive element is integrated into the encapsulant, wherein the encapsulant passes an optical signal from the optical emitter to the diffractive element.

Abstract: An optical encoder device comprising a first optical encoder on a first surface of a substrate and a second optical encoder on a second surface of the substrate, wherein an optical emitter and optical detector pair of the first optical encoder and an optical emitter and optical detector pair of the second optical encoder are mounted on the first surface and the second surface of the substrate, respectively.