An encoder, including: a scale that has a pattern and is mountable to a rotary member of an object to be measured; a main body including a detector that detects the pattern, the main body being mountable to a non-rotating portion of the object to be measured; and a holding member including: an abutment portion that is removably provided to the main body from outside the main body and passes through the main body to abut the scale; and a pushing portion that is capable of pushing the abutment portion toward the scale.

An arrangement includes a carrier and a scale disposed on the carrier in a spaced-apart relation therewith. The scale has a measuring graduation and is attached to the carrier via areally distributed and spaced-apart adhesive dots. The adhesive dots, which can be circular in shape, each include at least three spacers, which can be spheres, enclosed within an adhesive.

A rotary encoder for a valve comprises a rotatable code plate and an optical detector module comprising one or more optical detectors. The code plate defines a set of voids arranged along a set of one or more concentric circular arcs about an axis of rotation. The voids define an angle-dependent pattern over the set of arcs, the pattern comprising a plurality of distinct sectoral elements (A-O, X). At least two of the sectoral elements, located in non-adjacent sectors of the code plate, are identical, but the pattern is non-repeating over a single full rotation of the code plate about the axis. Each optical detector is aligned with a respective concentric circular arc of the code plate. A controller processes time-varying output signals from the optical detectors to determine successive positions of the rotatable code plate.

An encoder scale includes a tabular base material and an optical pattern provided above one surface of the base material, a first region and a second region being disposed side by side above the optical pattern. The first region includes a resin layer disposed above the base material and including photosensitive resin and a metal film disposed above the resin layer and formed of a metal material. The surface of the first region is configured mainly by a first surface having a normal line in the thickness direction of the base material. The surface of the second region is configured mainly by a second surface inclined with respect to the first surface.

An encoder includes a disc and a sensor. The disc has a circular surface with a central axis and is rotatable around the central axis. The disc has a slit row provided on the circular surface. The slit row includes slits arranged in a circumferential direction of the circular surface around the central axis and in a radial direction of the circular surface. The sensor is provided opposite to the slit row on circular surface. The sensor has a first light receiver and a second light receiver. The first light receiver is configured to output a first light receiving signal as the slit row rotates along the circumferential direction when the disc rotates around the central axis. The second light receiver is configured to output a second light receiving signal as the slit row moves along the radial direction when the disc rotates around the central axis.

An optical reflective component and an optical encoder using the same are disclosed. The optical reflective component includes a main body, an optical pattern, a first attaching portion and a second attaching portion. The main body has a first central axis and a reflective surface perpendicular to each other. The optical pattern is disposed on the reflective surface and centered at the central axis. The first attaching portion is centered at the first central axis of the main body and extends from the man body in a direction parallel to the first central axis. The first attaching portion has an inner wall. The second attaching portion has a plane perpendicular to the first central axis. The plane is connected to the inner wall. The main body, the first attaching portion and the second attaching portion are formed of a metal material and are integrally formed with the optical pattern.

In a rotary motion detecting device that outputs a signal corresponding to rotary motion of a rotary disk coupled to a shaft, a boss is fixed to the shaft, the boss is fixed to one surface of the rotary disk, and one of the boss and the shaft is a hole member having a hole formed therein and the other is an inserted member that is inserted in the hole. The hole member has an inner periphery (inner diameter) that is larger than an outer periphery (outer diameter) of the inserted member so that the shaft can be vertical to the rotary disk without being restricted by the boss.

A scale includes: a substrate; scale gratings that are formed on a face of the substrate and has a plurality of metal gratings at a predetermined interval; and an inorganic transparent member that is provided between the plurality of metal gratings, wherein at least a surface of the face of the substrate is made of a metal, and wherein the scale gratings and the inorganic transparent member are exposed to atmosphere.

An optical detection system includes a marker product and an optical encoding device. The marker product includes a substrate and at least one structural portion. The structural portion has a first surface, a second surface and a dividing axis. The first surface and the second surface are arranged on opposite sides of the dividing axis. A sidelong direction aligning the first surface with the second surface is parallel to a moving direction between the optical encoding device and the marker product. The optical encoding device is disposed adjacent by the marker product. The optical encoding device includes an optical projector and an optical encoder. The optical projector is configured to project the optical detecting signal onto the marker product. The optical encoder is configured to receive an optical reflecting signal from the marker product and encode intensity variation of the optical reflecting signal into digital data.

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.