Mitutoyo Corporation

Miyako Mizutani

Tatsuya Nagahama

Eric Altendorf

Toshitaka Shimomura

Shingo Nihommori

Joseph Daniel Tobiason

Toru Yaku

Yoshiaki Kato

Takashi Matsumoto

Kimitoshi Ono

Fujio Maeda

Shunsuke Tanaka

Eric Herbert Altendorf

An angle detector includes a rotary scale having a scale pattern in which a plurality of patterns are arrayed along a circumference direction of the rotary scale, and a plurality of detection heads, each of which detects the plurality of patterns from the scale pattern. The plurality of detection heads are shifted from each other in the circumference direction of the rotary scale and are shifted from each other in a radial direction of the rotary scale.

Angle detector and position measuring device

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.

Photoelectric rotary encoder

An electromagnetic inductive encoder that can suppress the effect of changes in magnetic flux received by the receiver section and maintain the accuracy of measurement results is provided. The electromagnetic inductive encoderincludes a scaleand a headthat is provided to face the scaleand moves relative to the scale. The headincludes a transmitter sectionand a receiver sectionwith a plurality of receiving coils. The receiver sectionhas a first receiver sectionwith at least one receiving coil, a second receiver sectionthat is provided apart from the first receiver sectionand has at least one receiving coildifferent from the first receiver section, and connection wiringthat connects the first receiver sectionand second receiver section. The first receiver sectionand the second receiver sectionare arranged linearly symmetrically with the axis Lof the Y-direction, which is orthogonal to the X-direction (measurement direction) in the planewhere the receiving coilsare arranged, and are arranged in the same number.

Electromagnetic inductive encoder

A life detection device of an encoder is used for the encoder including a scale and a head. The scale is housed in a scale frame. The head relatively moves along the scale to detect an amount of relative movement with the scale. The life detection device includes environmental condition detection means, life determination means, and informing means. The environmental condition detection means is configured to detect an environmental condition related to life detection in the encoder. The life determination means is configured to determine a life of a component constituting the encoder based on a detection result by the environmental condition detection means. The informing means is configured to inform the life based on a determination result by the life determination means.

Life detection device for encoder

Provided is a photoelectric encoder that can achieve higher accuracy while maintaining reliability by reducing stray light. An encoderis a photoelectric encoder including a light source devicethat emits parallel light, a scalehaving calibrations C provided along a measurement direction, and a light receiving unitthat receives light being emitted from the light source device, and transmitted through the scale. The encoderincludes an antireflection memberthat prevents stray light generated by being reflected on the scale, from entering the light receiving unit. Because the encoderincludes the antireflection member, the encodercan achieve higher accuracy while maintaining reliability by reducing stray light entering the light receiving unit

Photoelectric encoder

Provided are a light source device that can achieve higher accuracy while maintaining reliability by reducing stray light, and a photoelectric encoder including the same. A light source deviceincludes a translucent memberconfigured to accommodate a light emitting unitthereinside, and to make light emitted from the light emitting unitinto parallel light. The translucent memberincludes an optical axis planean orthogonal planea reflection portion configured to make light from the light emitting unitinto parallel light, and a connection portionformed by the optical axis planeand the orthogonal planeconnecting to each other, and having a curved surface. A central axis AX of the curved surface is in an outside region of the translucent memberand a region between the optical axis planeand the orthogonal plane

Light source device and photoelectric encoder including the same

A miniaturized optical encoder capable of obtaining a sufficient amount of light in the light receiving element is provided. An optical encoderincludes a scalehaving a scale track' and a readheadhaving a light sourcethat emits light to the scale track&#x2032;, a scale-side lensthat transmits the light emitted from the light sourceto the scale track&#x2032;, and a light receiving elementthat receives the light reflected by the scale track&#x2032; through the scale-side lens. The light sourceis arranged between the scale-side lensand the light receiving element. An optical axis Lsrc of the light sourceis matched with an optical axis Ls of the scale-side lensin a reading direction of the scaleand is separated from an optical axis Ls of the scale-side lensby a predetermined distance D in a direction perpendicular to the reading direction of the scale

Optical encoder using off-axis imaging through a lens

A miniaturized optical encoder capable of obtaining a sufficient amount of light in the light receiving element is provided. An optical encoderincludes a scalehaving scale markingsand a readheadhaving a light sourcethat emits light to the scale, a scale-side lensthat transmits the light emitted from the light sourceto the scale, and a light receiving elementthat receives the light that has been reflected by the scaleand that has passed through the scale-side lens. The light sourceis arranged between the scale-side lensand the light receiving element, and a distance between the light sourceand the scale-side lensis set to be a focal distance fs of the scale-side lens. An optical axis Lsrc of the light sourceis matched with an optical axis Ls of the scale-side lensin a reading direction of the scale markingsand is separated from an optical axis Ls of the scale-side lensby a predetermined distance D in a direction perpendicular to the reading direction of the scale markings

Optical encoder

In a photoelectric encoder including a scale () for making a relative move and an image forming optical system (), adapted to detect relative displacement of the scale, a transparent protective material () having a thickness t equal to or greater than the depth of focus (DOF) of the image forming optical system is disposed on the lattice () side surface of the scale. The transparent protective material can be transparent tapebonded to the lattice side surface of the scale or a transparent protective materialapplied to the lattice side surface of the scale. The surface of the transparent protective material can have hydrophilicity or lipophilicity.

Photoelectric encoder with a transparent protective material having a thickness equal to or greater than a depth of focus of an image forming optical system disposed on the surface of a scale

A photoelectric encoder has a telecentric optical system in which a first lens and an aperture located at a focal position of the first lens are interposed between a main scale and a photoreceptor. At least a second lens is interposed between the aperture and the photoreceptor with a focus of the second lens on the aperture, thereby constituting a bilateral telecentric optical system. This makes it possible to improve the signal detection efficiency and increase the assembly tolerance.

A displacement measuring device including a scale, and an optical readhead including an index pattern and a light receiving element is provided. A bright/dark pattern arising from a scale grating is detected by the readhead to measure displacement. In various embodiments, a magnification of the pattern is adjusted by the spacing between at least a lens element, aperture element, and detection plane of the readhead. An aperture can be designed to provide a diffraction-limited telecentric imaging configuration that filters an image of the scale grating to provide a sinusoidal intensity pattern that supports highly interpolated measurements. An aperture dimension, selected in relation to the grating pitch and other parameters, can provide a desirable combination of readhead operating characteristics including one or more of a desired depth of field; degree of spatial filtering; and optical signal power.

Optical configuration for imaging-type optical encoders

A photoelectric encoder that has a lens optical system including a lens inserted between a main scale and a light receiving element. In the photoelectric encoder, three planes extended from a surface of the main scale, a principal plane of the lens, and an image plane of the light receiving element are disposed so as to intersect at a single point and satisfy the Scheimpflug rule. Focus can thereby be obtained over the entire image plane, so that a reduction in contrast is prevented, even if the optical axis is inclined to make an optical system smaller.

A photoelectric encoder is provided which has an optical system including a first lens array inserted between a main scale and a light receiving element. An image divided or reversed by the first lens array can be electrically or optically re-reversed. This can achieve the reduction of the entire size as well as increase in the scale field of view, while maintaining the image shape and/or pattern.

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Kawasaki, Japan

Miyako Mizutani