Abstract: A light-emitting element driving circuit comprising, a light-emitting element, a driving unit which has a control terminal and is configured to drive the light-emitting element according to a potential of the control terminal, a node connected to the control terminal, a monitor configured to monitor an emitted light amount of the light-emitting element, a potential control unit configured to control a potential of the node so that the emitted light amount of the light-emitting element approaches a target value, and an auxiliary potential control unit configured to assist potential control of the node by the potential control unit when a difference between the emitted light amount of the light-emitting element detected by the monitor and the target value is larger than a reference amount.

Abstract: A reflective optical scale for an encoder, in which a first region and a second region are alternately arranged on an underlying member, wherein the first region has a reflecting member on the underlying member, a layer made up of a first material, and a layer made up of a second material, the second region has the layer made up of the second material, the first and the second material have transparency, the first material has a lower refractive index of the light than the reflecting member and the second material, the second material has a lower refractive index of the light than the underlying member, and optical thicknesses of the first and the second material are set so that a reflectance of the light of the first region is higher than the second region.

Abstract: A portable terminal device is disclosed that includes a movable part having a display part; an arm part supporting the movable part so that the movable part is rotatable at least ±90° with reference to a rotation center position around a rotation center; and a position detection part detecting the position of the movable part relative to the arm part. The position detection part includes magnets, magnetic sensors detecting the magnetic fields thereof, and a calculation part determining the position of the movable part based on sensor outputs. The magnets are provided in one of the arm part and the movable part so as to be 90° apart from each other around the rotation center. The magnetic sensors are provided in the other one of the arm part and the movable part so as to oppose the corresponding magnets when the movable part is positioned at the rotation center position.

Abstract: An optical encoder may include an encoder disk, an illumination system, and a detector to detect light diffracted from the encoder disk. The encoder disk may include a signal track comprising a diffraction grating, and an index track comprising a reflective index mark, wherein a width of the index mark is larger than a pitch of the diffraction grating. An indexing method may include providing an encoder disk, providing an illumination system to direct light to the encoder disk, providing a detector structured to detect light diffracted from the encoder disk, calculating an estimated count of quadrature states from a rising edge of an index pulse to a middle of the index interval, and calculating the quadrature state at an approximate center of the index pulse. A dynamic parameter correction method may include calculating a target gain and offset and correcting values based on the target gain and offset.

Abstract: An optical readhead for measuring a displacement along a measuring axis direction between the readhead and a scale track comprises an illumination portion configured to output source light to the scale track and a monolithic detector configuration. The monolithic detector configuration comprises: a first track photodetector portion configured to receive scale light from the scale track; a first metal layer; a second metal layer; and a plurality of dummy vias between the first metal layer and the second metal layer. The plurality of dummy vias is arranged to block light transmission along a layer between the first and second metal layers, and the plurality of dummy vias is formed by the same process steps used to fabricate a plurality of active vias used to connect circuit elements on the monolithic detector configuration.

Abstract: A photoelectric encoder includes a light-emitting element, a scale, a lens, a PDA, and a signal processing circuit. The signal processing circuit includes a distortion table, a distortion compensation circuit, and a position analyzing circuit. The distortion table is calculated in advance on the basis of pieces of distortion information that were obtained by a distortion simulation using design values of the optical system such as the lens. The distortion compensation circuit corrects a light/dark signal of the PDA by eliminating distortion caused by the optical system by changing the positions of the respective PDs of the PDA virtually on the basis of the distortion table and the pieces of position information of the respective PDs. The position analyzing circuit analyzes a position of the scale on the basis of the corrected light/dark signal.

Abstract: The encoder includes a scale including first and second periodic patterns, and a detector relatively movable with respect to the scale and whose detection state is switchable between a first detection state to read the first periodic pattern and output a first signal and a second detection state to read the second periodic pattern and output a second signal. A processor performs a first process to detect a first absolute position by using the first and second signals and then performs a second process to calculate a relative movement amount by using a specific signal that is one of the first and second signals and detect a second absolute position by using the relative movement amount and the first absolute position. The specific signal is obtained from the detector set in a same detection state as that set last in the first process.

Abstract: A displacement detecting device includes: a scale which has an optical lattice; a detecting unit which is disposed so as to be movable in a scanning direction relative to the scale, inclusive of at least a first detection portion, a second detection portion and a third detection portion, arranged in the scanning direction for detecting position information from the optical lattice; and a calculating portion configured to obtain a self-calibration curve on graduations of the scale by specifying positions of the detection portions and calculating measurement error based on the position information detected by the detecting unit, wherein: the detecting unit is provided so that a distance between the first detection portion and the second detection portion and a distance between the second detection portion and the third detection portion are different from each other and do not form an integral multiple.

Abstract: An optical sensing device includes a shell, at least one light emitting member, a rotator type shading member and at least one optical sensing member. The shell is formed with a black-body condition space having a light emitting chamber, a shading chamber and at least one optical sensing chamber. The light emitting member projects a light beam. The rotator type shading member is rotatably restrained within the shading chamber, and has a geometric center and a weight center offset from the geometric center. When the optical sensing device is lifted in a lifting azimuth or lowered in a lowering azimuth, the rotator type shading member is rotated by the geometric center to make the weight center located in the lowering azimuth with respect to the geometric center. The optical sensing member is arranged in the optical sensing chamber, and senses the light beam to accordingly send out a sensing signal.

Abstract: An encoder apparatus comprises a first scale member with a scale region on which a scale is arranged; a detector that detects light from the scale region; and a retaining member with a retaining surface that is arranged so as to face a surface of the first scale member including the scale region via a predetermined gap, and that retains a liquid at least between the retaining surface and the first scale member.

Abstract: A scanning unit that includes a radiation source that emits electromagnetic radiation, which is used to scan a scale of a position measuring system, wherein the radiation source includes electrical connection elements. The scanning unit further including a holder upon which the radiation source is fixable, wherein the holder includes electrical conductor elements that electrically contact the electrical connection elements. The electrical conductor elements of the holder and the electrical connection elements of the radiation source form a guide on which the radiation source is movable along an adjustment path relative to the holder while maintaining electrical contact between the electrical connection elements and the electrical conductor elements. Maintaining electrical contact enables positioning the radiation source at various positions along the adjustment path on the holder wherein the electrical connection elements are in electrical contact with the electrical conductor elements.

Abstract: A motion sensor having a coiled member, light emitter, and light detector. The coiled member is bendable in response to lateral forces applied thereto. The coiled member defines an internal open ended channel having a first end opposite a second end. The emitter is adjacent the first end and emits light into the channel. At least a portion of that light travels through the channel toward the second portion. An amount of light reaching the detector is determined at least in part by how much the coiled member is bent. The detector is adjacent the second end and receives light from the channel. The detector is configured to transmit a signal indicating an amount of light received. The signal may be used by a motion capture system to animate a computer generated animation. Multiple motion sensors may be incorporated into a glove and positioned to detect bending of finger joints.

Abstract: An absolute position measuring encoder having an ABS/INC integrated pattern obtained by integrating an absolute pattern and an incremental pattern together is provided. The absolute position measuring encoder includes an imaging optical system (lens) designed to generate an amplitude difference between a light and dark signal derived from the absolute pattern and light and dark signal derived from the incremental pattern, and a signal processing system (comparator) for separating a received light signal from the ABS/INC integrated pattern into an absolute pattern signal and an incremental pattern signal by utilizing the amplitude difference. Accordingly, an absolute pattern signal and an incremental pattern signal can be separated off from the ABS/INC integrated pattern at a high speed with a simple processing circuit.

Abstract: A measurement system (22) for measuring the position of a work piece (28) includes a measurement grating (34) and an encoder head (36). The encoder head (36) directs a measurement beam (252) at the measurement grating (34), the measurement beam (252) having an oval shaped cross-section. The encoder head (36) includes a beam shape adjuster (256) positioned in the path of an input measurement beam (240) having a substantially circular cross-sectional shape that transforms the input measurement beam (240) to provide the measurement beam (252) having the oval shaped cross-section.

Abstract: An optical encoder and optical encoding system are disclosed. Specifically, an encoder having a light detector elevated relative to a light source is described. The relative height difference between the light source and the light detector enables the optical encoder to minimize noise at the light detector without requiring a separate light baffle between the light source and light detector. Methods of manufacturing and operating such an encoder are also described.

Abstract: A reflection plate for an optical encoder includes: a base material (1) with a reflecting surface; and a film (3) that is formed on a part of the reflecting surface and includes a non-electrolytic plating film or an electrolytic oxide film.

Abstract: A scale of an absolute encoder, on which a plurality of marks are arranged at predetermined pitches along at least one direction, includes: a base including a plurality of light-reflective or light-transmissive marks arranged at the predetermined pitches along the at least one direction. A film, which attenuates light, is formed on each of marks as a part of the plurality of marks.

Abstract: A rotary encoder and an optical wheel for the rotary encoder are provided. The rotary encoder further includes a light source module, a code plate and an optical sensor module. The light source module is coupled with the code plate. The optical wheel is rotary, and has imaging elements arranged annularly; at least one of the imaging elements is coupled with the code plate. The optical sensor module is coupled with at least one of the imaging elements. The light source module emits lights to the code plate, and the lights passing through the code plate forms an image which is then transmitted to the optical sensor module via the imaging element. When the optical wheel rotates, the image moves accordingly. The optical sensor module senses that the image moves. A method for generating a zeroing signal of a rotary encoder and a liner encoder are also provided.

Abstract: An object of the present invention is to provide a position detecting device using a reflection type photosensor, which assures a small size and low cost and enables detection of a long distance of about 10 mm or more, and a position detecting method. The position of a moving body is detected by providing, on the moving body, a reflection plate (12) having reflecting surfaces (sa) and non-reflecting surfaces (sb) arranged alternately in a moving direction of the moving body, providing a light receiving element (8) of the reflection type photosensor (9) with, for example, two light receiving portions (8a and 8b) having different light receiving regions in the moving direction of the moving body, outputting output signals from these two light receiving portions (8a and 8b), and carrying out at least one calculation of adding, subtracting, dividing and function calculation of these two output signals.

Abstract: An optical encoder system with a passive readhead is provided. The passive readhead does not have an attached cable and is an all optical readhead where the measurement position information relative to a scale is read remotely by direct line-of-sight optical transmission to a remote companion system. The remote companion system includes a light source and a sensing portion. In one embodiment, the sensing portion may comprise a remote lens portion and a photodetector arrangement. The remote companion system is configured to optically sense intensities of imaged regions from the passive readhead, and to output a plurality of signals indicative of the measurement position based on the sensed intensities.

Abstract: A two-dimensional absolute encoder includes; a scale on which marks are arranged at predetermined pitches along first and second directions; a detector configured to detect a number of marks arranged in each direction; and a processor configured to obtain an absolute position of the scale in the each direction based on outputs from the detector. Each mark has one of characteristic corresponding to information of a quantized code used for indicating a position in the each direction. The processor is configured to generate a code sequence including the number of codes based on detection of the number of marks and information corresponding to the characteristic, and to obtain an absolute position of the scale in the each direction based on the code sequence.

Abstract: A linear position measuring system and a method for determining an absolute position of a carriage along a slide rail are disclosed. An analog signal progression (S) based at on at least one reference point is here discretely scanned in response to a first threshold (SW1) and second threshold (SW2). The resultant digital values are stored in a first measured value register (MR1) and a second measured value register (MR2). The contents of the first and second measured value register (MR1, MR2) are compared with the respective contents of a first and second set measured value register. The reference point is output as an ideal reference point if the differential value lies within a predetermined tolerance range, and is otherwise discarded.

Abstract: Disclosed is a displacement sensor configuration, comprising a scale grating disposed in a first direction; and a scale light imaging configuration which includes first and second optical paths and a detector including first and second detector portions. The imaging portion inputs a first scale light component output by the scale grating along the first optical path and transmits the first scale light component to the first detector portion, the imaging portion inputs a second scale light component output by the scale grating along the second optical path and transmits the second scale light component to the second detector portion, the first detector portion is configured to output a first displacement signal indicative of a displacement along the first direction, and the second detector portion is configured to output a second displacement signal indicative of a displacement along a second direction perpendicular to the first direction.

Abstract: An optical position-measuring device includes a measuring standard and a scanning unit. The measuring standard includes an incremental graduation and at least one reference marking at a reference position. The reference marking has two reference-marking subfields disposed in mirror symmetry relative to a reference-marking axis of symmetry, each of the subfields including a grating structure having a locally changeable graduation period. The scanning unit includes a divergently emitting light source, one or more gratings, and a reference-signal detector system. The reference-signal detector system has at least four detector arrays formed and positioned such that, from the scanning of the reference marking via the reference-signal detector system, first and second pairs of partial reference signals result, in each case having a signal pattern in phase opposition. The first pair of partial reference signals is offset by an offset amount relative to the second pair of partial reference signals.

Abstract: An encoder includes a scale that includes a pattern row, a detector array, and a signal processor. The pattern row has a plurality of different modulation periods in the moving direction, an amplitude of the energy distribution in the pattern having at least one modulation period being configured to change with a position of the scale in the moving direction. The signal processor acquirers an amplitude of an energy distribution of a corresponding modulation period based on an output signal from the detector array, and an amplitude signal obtained by normalizing a plurality of amplitudes obtained by the plurality of amplitude acquirers, the amplitude signal serving as a position signal representative of the position of the scale.

Abstract: An encoder includes a scale that includes a plurality of unit block patterns arranged in a position measuring direction with a period of a pitch. A pattern of the unit block pattern has a symmetrical shape with respect to a symmetry line perpendicular to the position measuring direction. Each unit block pattern includes a plurality of divided sections along a direction perpendicular to the position measuring direction. An area ratio of the pattern which is a value made by dividing an area of the pattern in each divided section by an area of the divided section is different between two adjacent divided sections. The pattern in each divided section has a rectangular shape defined by two parallel lines that extend in the position measuring direction and two parallel lines that extend in the direction perpendicular to the position measuring direction.

Abstract: An optical encoder includes a light source, a scale which is irradiated by the light source and has a fine pitch pattern and a coarse pitch pattern in one track, a photo detector array which detects transmitting light or reflected light from the scale which are emitted from the light source, a signal processing unit including a first initial-stage amplifier unit that generates a position detection signal from the photo detector array, and a control unit that uses an output signal from the first initial-stage amplifier unit to control a light amount variation of the light source. The optical encoder can operate in a high resolution detection mode that forms the photo detector array at a first pitch to detect the fine pitch pattern and a low resolution detection mode that forms the photo detector array at a second pitch to detect the coarse pitch pattern.

Abstract: An optical encoder includes a light source, a scale which is irradiated by the light source and has a fine pitch pattern and a coarse pitch pattern in a measuring direction in one track, a high resolution detection sensor array which receives light from the scale and detects the fine pitch pattern, and a low resolution detection sensor array which receives light from the scale and detects the coarse pitch pattern. A transmittance distribution or a reflectivity distribution of the scale is a distribution obtained by summing up a modulation component which corresponds to the fine pitch pattern and in which integrated values in a direction perpendicular to the measuring direction form modulation amplitude uniform in the measuring direction and a modulation component which corresponds to the coarse pitch pattern and in which modulation amplitude is uniform in the measuring direction.

Abstract: The present invention relates to an injection device comprising an optically-based sensor for determining the position or setting of a dose setting member arranged to set a dose to be injected from the injection device. In particular, the present invention relates to an injection device comprising a rotatably mounted member having a plurality of optically coded paths arranged on an outer surface thereof. The rotatably mounted member is operatively connected to the dose setting member and is adapted to rotate with the dose setting member.

Abstract: An encoder includes a slit array along a first measurement axis, and an optical module capable of relatively moving with respect to the slit array. The optical module comprises a point light source that irradiates the part of the slit array, and a light receiving array comprising a plurality of light receiving elements along a second measurement axis and arranged in positions offset with respect to the point light source. The light receiving elements is receiving light irradiated from the point light source and reflected from the reflection slit. The plurality of light receiving elements comprises respective shapes such that the light receiving element nearer to the point light source comprises a shorter length in a width direction and end parts on an opposite side of the light receiving element with respect to the point light source are arranged side by side in positions along the second measurement axis.

Abstract: An optical encoder includes a scale having diffraction gratings formed at predetermined pitches in a measurement axis direction, a detection head relatively movable with respect to the scale, the detection head including a light source portion configured to irradiate the scale with light, and a plurality of receiver portions configured to receive light reflected by or transmitted through the diffraction gratings of the scale, at different phases, and a signal processing device configured to perform signal processing to light reception signals output from the receiver portions of the detection head, to produce quadrature differential signals. The signal processing device is configured to calculate alignment adjustment monitor signals corresponding to a Lissajous radius of the quadrature differential signals in order to detect misalignment of the detection head with respect to the scale.

Abstract: In certain embodiments, a detection device includes a structure having an entrance that permits radiation to enter the structure and a radiation detector operable to detect radiation that enters the structure. The device also includes a microshutter array coupled to the structure and aligned with the entrance, the array comprising a plurality of microshutter cells operable to move between a first position in which that microshutter cell prevents radiation of a first wavelength from passing through a portion of the entrance and a second position in which that microshutter cell permits the radiation of the first wavelength to pass through the portion of the entrance. The device further includes an actuating device operable to define a first entrance pupil having a first f-number by moving a plurality of microshutter cells associated with the first f-number.

Abstract: Optical encoders supply binary logic signals representing the relative position increments of two elements of the encoder, the two elements being mobile relative to one another. The first element bears at least one mark and the second element bears a pair of detection cells for detecting the mark. The dimensions of the mark are defined so that said mark can be detected either by neither of the two cells, or by a single cell or by both cells. The invention is well suited to angular encoders, and makes it possible to widen the manufacturing tolerances of the marks on the first element and on the relative position of the two cells.

Abstract: An optical displacement detection apparatus includes a scale and a sensor head. The scale has a first and second pattern. The head includes a first photodetector that detects a beam through the first pattern and generates a first signal, and a second photodetector that detects the beam through the second pattern and generates a second signal. The first and second signals include a first component, and a second component that corresponds to an absolute displacement of the scale. The first pattern, the second pattern, the first photodetector, the second photodetector, and a beam source are disposed such that the detection of the first photodetector and the detection of the second photodetector are performed correlatively.

Abstract: An optical position-measuring device includes a scanning bar extending in a first or second direction, and a scale extending in the other direction. The scale is offset by a scanning distance from the scanning bar in a third direction perpendicular to the first and second directions. The device has a light source whose light penetrates the scanning bar at an intersection point of the scanning bar and scale to fall on the scale and arrive back at the scanning bar. At a detector, the light is split by diffraction into different partial beams at optically effective structures of the scanning bar and scale and combined again. A periodic signal is obtained in the detector in response to: a shift between the scanning bar and scale in the first direction due to interference of combined partial beams, and a change in the scanning distance between the scanning bar and scale.

Abstract: Disclosed are various embodiments of a reflective optical encoder having at least three channels—two data channels and one index channel—disposed along a common axis or single track. The single track configuration disclosed herein permits very high resolution reflective optical encoders in small packages to be provided. In addition, the single track configuration reduces problems with misalignment between code scales and light detectors, permits relatively simple electronic circuitry to be used to process outputs, and reduces manufacturing, assembly, integrated circuit and encoder costs. Methods of making and using such optical encoders are also disclosed.

Abstract: Disclosed are various embodiments of high-speed, high-performance, low-noise, low-cost, compact, optical encoders having a multi-faceted flat-faced lens disposed over the light emitters and light detectors thereof. Disclosed also are various means for preventing undesired stray light from reaching light detectors incorporated therein. Structures employed to block stray light in the optical encoders include light barriers, air gap trenches, and coatings disposed between first and second sides of a substrate of the encoder. Methods of making such optical encoders are also disclosed.

Abstract: A method for interpolating an encoded signal of encoders is disclosed. The first step may include generating four first stage signals having a first frequency that are 45 degrees out of phase. The four signals may then be multiplied to obtain a plurality of second stage signals that are 90 degrees out of phase having a second frequency two times the first frequency. The second stage signals may then go through further computation to obtain a plurality of third stage signals that are 45 degrees out of phase. The third stage signals may be further adapted for further multiplication to obtain higher levels of interpolation. Interpolators and optical encoders characterized by the interpolation capability are also disclosed.

Abstract: A photoelectric encoder includes a scale in which diffraction gratings are formed at predetermined pitches in a measurement axis direction, a detection head which is relatively movable with respect to the scale, and which includes an illuminating portion configured to illuminate the scale, and a light receiving portion configured to receive light reflected by or transmitted through the diffraction gratings of the scale, a signal processing device configured to process a light reception signal output from the light receiving portion of the detection head, and a signal transmitting unit configured to transmit a signal between the detection head and the signal processing device. The signal processing device includes a display unit configured to display information indicating an attachment posture of the detection head with respect to the scale.

Abstract: A detection head includes a plurality of detection array portions that are arranged in a direction along which the head is relatively displaceable. Position signals indicating a position of the detection head are calculated from output signals output from the detection array portions. In order to combine the position signals with one another and determine the position of the detection head with respect to the scale, weighting according to a level of the output signal is performed on the position signal of each of the detection array portions, and the weighted position signals are averaged.

Abstract: An origin location detection circuit in an encoder. The encoder includes a scale on which an origin pattern indicating an origin is provided and a detection head relatively displaceable with respect to the scale. The origin location detection circuit includes a comparator for generating an origin signal indicating a location of the origin from an output voltage signal, which is output from a detector of the detection head and has been affected by involvement of the origin pattern; a DC voltage detection circuit smoothing the output voltage signal; and a differential amplifier circuit performing differential amplification of the output voltage signal and a DC voltage signal output from the DC voltage detection circuit. A differential amplifier signal of the differential amplifier circuit is input to the comparator.

Abstract: A color temperature correction device corrects, in a display device that represents brightness of RGB of a video signal by a plurality of levels of gray scales, a color temperature of the video signal. The color temperature correction device includes: a recording means of storing a gray scale value conversion table for an input gray scale value of a video signal to set gray scale values for respective RGB, so that a consistent color temperature is maintained; and a gray scale value converting unit that converts the input gray scale value to set gray scale values, based on the gray scale value conversion table.

Abstract: An air-driven shutter device is used in an optical analyzer. The optical analyzer includes a measurement field to which a sample is supplied, a light-emitting unit measurement field for emitting measuring light to the sample, a light-receptive unit for receiving the measuring light that has passed through the sample, and a purge air supplying unit for supplying purge air. The air-driven shutter device includes a shutter and a shutter opening and closing mechanism. The shutter is disposed between the light-emitting unit and/or the light-receptive unit and the measurement field. The shutter opening and closing mechanism keeps the shutter open with pressure of the gas supplied from the purge air supplying unit, and closes the shutter when the pressure of the gas supplied from the purge air supplying unit becomes lower than a predetermined level.

Abstract: An absolute encoder includes a scale in which plural marks are arranged at a first pitch; a detector configured to detect a predetermined number of marks corresponding to one of the absolute codes; and a calculator configured to calculate an absolute position of the scale based on an output of the detector. The calculator is configured to generate a data sequence constituted by the predetermined number of data by respectively quantizing the predetermined number of periodic signals output from the detector, and to obtain first position data corresponding to the one of the absolute codes based on the generated data sequence, to obtain second position data based on a phase of at least one of the predetermined number of periodic signals, and to generate data which represents the absolute position by combining the first position data and the second position data.

Abstract: An encoder system and method are provided, that is designed to improve 2D encoder systems and methods in areas such as accuracy, compactness, stability, resolution, and/or light efficiency. Moreover, the system and method of this invention provides a new concept in a retroreflector that while particularly useful in applicants' system and method, is believed to have more general utility in optical imaging systems and methods.

Abstract: A position encoder kit, including: a scale comprising a series of position features; and a readhead. The readhead includes a detector for receiving configuration information from a configuration item. The readhead is configured to operate in accordance with the configuration information. The readhead also includes a receiver interface via which the readhead can supply position information to a receiver.

Abstract: Tactile sensor. The sensor includes a compliant convex surface disposed above a sensor array, the sensor array adapted to respond to deformation of the convex surface to generate a signal related to an applied force vector.

Abstract: According to one embodiment, an optical sensor includes a photodetector and a substrate. The photodetector detects light. The substrate in which the photodetector is received includes at least three layers including a cover layer, a spacer layer, and a base layer. The substrate includes an electrical conductive portion for the photodetector.

Abstract: Measuring devices each include a rotating body arranged between a wheel and a wheel hub with rotation centers aligned with each other, and an optical detector fixed to a body frame. The rotating body is formed of a disk portion attached between the wheel and a mounting surface of the wheel hub, and a cylindrical portion extending from the disk portion to the body frame and encompassing an outer circumferential surface of the wheel hub. In a circumferential surface of the cylindrical portion, there are provided elongate holes as light-transmitting portions that transmit light therethrough. The optical detector includes a light-emitting element serving as a light-emitting portion and a light-receiving element serving as a light-receiving portion, which are fixed to the body frame by a mounting bracket.

Abstract: A rotating shaft; a boss that has a fitting hole formed in a center portion thereof, has a clean adhering surface at an end thereof, and is configured so that the rotating shaft is fitted into the fitting hole while the boss is fixed to the rotating shaft by a fixing member; a pulse disk that has an interference-fit hole formed in a center portion thereof for the rotating shaft, has a clean adhesion-receiving surface in a surrounding of the interference-fit hole, is configured so that the rotating shaft is pressed into the interference-fit hole and so that the adhesion-receiving surface is adhered to the adhering surface of the boss by an adhesive agent, and has a position detecting pattern formed thereon; a light emitting element that radiates light; and a light receiving element that receives the light from the light emitting element via the position detecting pattern are included.