An optical encoder comprises an emitter; a receiver; a reflector; and a code carrier, wherein the emitter emits electromagnetic radiation along an emission axis in the direction of the reflector and the reflector deflects the electromagnetic radiation along a reception axis in the direction of the receiver. The code carrier is movably supported and has a sequence of code sections to interrupt or to give way for the emitted electromagnetic radiation to impinge on the detector in dependence on the position of the code carrier, wherein the emission axis and the reception axis extend at an alignment angle with respect to one another that has a value in the range from 30 degrees to 150 degrees.

The photoelectric rotary encoder includes: a generally disk-shaped scale with a grating-like pattern formed with a predetermined period along a measurement direction, the measurement direction being a direction of rotation of a measurement target that rotates on a predetermined axis, the scale being plate-like and centered on an axis of rotation; and a head that detect, from the scale, the amount of displacement caused by the rotation of the measurement target. The head includes a light source, a diffraction unit with grating parts, and a light-receiving unit with light-receiving elements. The grating parts of the diffraction unit are formed as deformed grating parts that spread cut wide, from the center on the axis of rotation, along the grating-like pattern of the scale. The light-receiving elements are formed as linear grating parts.

There is provided an optical encoder including an encoding medium, multiple photodiodes and a signal processing circuit. The encoding medium includes an index track. The index track includes a first index pattern and a second index pattern. The multiple photodiodes include a first index photodiode, a second index photodiode and a reference index photodiode for receiving modulated light from the first index pattern and the second index pattern. When the first index photodiode is aligned with the first index pattern and the second index photodiode is aligned with the second index pattern, the signal processing circuit outputs a triggering signal.

An encoder unit includes a magnetic encoder having a main gear fixed to a rotation shaft, a plurality of auxiliary gears meshing with the main gear, magnets placed in the respective auxiliary gears, and a plurality of magnetic sensors on which magnetic fields of the corresponding magnets act, an optical encoder placed apart from the magnetic encoder in an axial direction of the rotation shaft and having an optical scale fixed to the rotation shaft and an optical sensor receiving light reflected by the optical scale, and a substrate placed between the magnets and the optical scale and having one surface with the magnetic sensors mounted thereon and another surface with the optical sensor mounted thereon.

In an example, a circuit includes a first comparator, a second comparator, a pulse counter, a processor, a first ADC, and a second ADC. The first comparator has a first input coupled to a first node, a second input, and an output. The second comparator has a first input coupled to a second node, a second input, and an output. A first DAC is coupled to the second input of the first comparator. A second DAC is coupled to the second input of the second comparator. The pulse counter has a first input coupled to the output of the first comparator and a second input coupled to the output of the second comparator. The first ADC has an input coupled to the first node and an output coupled to the processor. The second ADC has an input coupled to the second node and an output coupled to the processor.

There is provided an optical encoder including an encoding medium, multiple photodiodes and a signal processing circuit. The encoding medium includes an index track. The index track includes a first index pattern and a second index pattern. The multiple photodiodes include a first index photodiode, a second index photodiode and a reference index photodiode for receiving modulated light from the first index pattern and the second index pattern. When the first index photodiode is aligned with the first index pattern and the second index photodiode is aligned with the second index pattern, the signal processing circuit outputs a triggering signal.

There is provided a light control circuit including a light detector, a frequency detector, an error amplifier, an NMOS driver and a light source. The frequency detector identifies a signal frequency according to detected voltage signals outputted by the light detector and generates a control signal accordingly. The NMOS driver changes a drive current of the light source according to an output of the error amplifier. The error amplifier changes a bandwidth thereof according to the control signal from the frequency detector to regulate a response time of the drive current of the light source.

Detection of mechanical coupling slippage in rotary encoder systems is provided where position data samples are obtained from a rotary encoder coupled to rotating element and angular acceleration data is determined based on the position data samples. At least two acceleration peaks are detected in the angular acceleration data, including at least one negative acceleration peak and at least one positive acceleration peak. Slippage occurrence of the mechanical coupling are detected when an interval between a negative acceleration peak and a positive acceleration peak of the at least two acceleration peaks is less than a first time period. If at least a threshold number of slippage occurrences are detected within a second time period, a mechanical coupling error signal is generated.

The optical scanning device includes a swingable reflector; a blocking unit that is provided in the reflector to move in linkage with the reflector; and a sensor unit that includes at least a first sensor unit and a second sensor unit, wherein each of the first and second sensor units includes an output unit, which is a light generator or an electromagnetic wave generator configured to output a detection target and a detection unit, which is a light receiver or an electromagnetic wave receiver configured to detect the detection target. The output unit is at a position that faces the detection unit. When the reflector is in a predetermined swing angle range, the blocking plate blocks a path of the detection target between the output unit and the detection unit.

An apparatus for measuring wire and cable length is provided for using a wireless encoder for wire and cable processing. The apparatus for measuring wire and cable length may include a housing, battery, communication component, microcontroller, printed circuit board, encoder module, encoder disc, shaft, wire counter and spool.