A position encoder includes a carrier adapted to move with respect to a first sensor and a second sensor of a position encoder. The carrier also includes encoding elements situated on the carrier to interact with the first sensor. A first limit indicator is situated at a first location on the carrier to interact with the second sensor at a first position of the carrier corresponding to a first limit of the position encoder, and a second limit indicator is situated at a second location on the carrier to interact with the second sensor at a second position of the carrier corresponding to a second limit of the position encoder.

In order to provide a small detection device capable of detecting an accurate absolute position with a single head, there is provided a detection device including a head including a light source and a detecting unit configured to receive multiplexed light (interference light) of diffracted light obtained by causing light from the light source to enter first two points residing on ax diffraction grating and being separated from each other by a known distance and diffracted light obtained by causing the light from the light source to enter second two points residing on the diffraction grating, being separated from each other by a known distance, and including at least one point being different from the first two points, wherein the diffraction grating includes a first region between the first two points separated from each other by the known distance and a second region between the second two points separated from each other by the known distance, the first and second regions having at least partially different grating interval lengths, and an absolute position on the diffraction grating is detected based on the multiplexed light (interference light) received by the detecting unit.

A reflective optical encoder has a hub member mounted on a rotation shaft, and a circular scale plate fixed to the hub member by an adhesive and having, on a front surface thereof, a pattern composed of high reflection portions having a high light reflectance and low reflection portions having a low light reflectance. Further, a step is provided at an outer peripheral portion of the hub member, and an outer diameter of the scale plate is larger than an outer diameter at an outermost peripheral portion of an adhesive surface of the hub member in which the scale plate and the hub member are bonded.

An encoder includes a carrier disc, a coded disc, a rotating shaft, a bearing, a bracket, a housing and a sensing assembly is disclosed. The coded disc is disposed on the carrier disc. The rotating shaft includes a first attaching portion and a second attaching portion, and the first attaching portion is partially penetrated through the carrier disc. The bearing includes a bearing inner surface and a bearing outer surface, and the bearing inner surface is connected with the second attaching portion. The bracket includes a bearing attaching portion and a bracket curved feature portion, and the bearing attaching portion is connected with the bearing outer surface. The housing includes a housing curved feature portion, which is connected with the bracket curved feature portion.

A rotation angle encoder apparatus is disclosed. The rotation angle encoder apparatus may comprise a plurality of light sources, a plurality of light detectors, and a plurality of pinions rotatable about a shaft. Each of the pinions may comprises a plurality of teeth and a plurality of gaps. The rotation angle encoder apparatus may comprise a plurality of stacked configurations such that, when the shaft is rotated, transmissivity may be measured to determine or calculate at least one measurement, such as an angle of rotation, position, movement, distance, or other discernable measurement. The rotation angle encoder apparatus with a plurality pinions and associated measurable transmissivities may enable an optical spectrum analyzer to increase wavelength accuracy and improve resolution in optical measurements.

A scale includes a base material, scale patterns arranged at a predetermined periodicity on a main surface of the base material, and a fluorine film that covers the scale patterns and is at least partly a monomolecular fluorine compound.

Example implementations relate to determining a correction factor that converts a measured sensor distance to a calibrated sensor distance. The measured sensor distance may be based on an amount of substrate advancement through a web printing press between detecting a mark on the substrate at a first sensor and detecting the mark at a second sensor. The calibrated sensor distance may be the separation between the first sensor and the second sensor.

An encoder includes a magnet, an optical coded disc, a magnetic sensing assembly, an optical sensing assembly and a signal processing unit. The optical coded disc has a first incremental pattern track and a second incremental pattern track. The magnet and the optical coded disc are structurally coaxial and rotatable. The magnet sensing assembly senses the magnet rotation to obtain an absolute position signal. The optical sensing assembly senses the optical coded disc rotation to obtain a first incremental position signal and a second incremental position signal. The signal processing unit receives and integrates those signals to obtain a high precision absolute position information.

A scale attachment device configured to attach a tape scale for a linear encoder includes a fixing block and housing members. The fixing block fixes the central part of the tape scale in the lengthwise direction by pressing the central part onto a target object. The housing members include a groove to house a remaining part of the scale on both sides of the fixing block. The tape scale is inserted into the groove in the lengthwise direction with its back surface facing the bottom surface of the groove of the housing member, and thus housed in the groove. The width dimension of the opening of the groove is smaller than the width dimension of the scale.

The invention provides a substrate treatment method and apparatus. Embodiments show a substrate in the form of a rotary encoder ring having a pattern of marks producable by means of a laser treatment device controllable to produce the pattern in the correct manner while there is continuous relative displacement between the ring and the laser treatment device.