Mitutoyo Corporation

Toru Yaku

Tatsuya Nagahama

Tetsuro Kiriyama

Kenji Okabe

Eric Altendorf

Miyako Mizutani

Kimitoshi Ono

Shingo Nihommori

Joseph Daniel Tobiason

Yoshiaki Kato

Toshihiko Aoki

Hiroaki Kawada

Osamu Kawatoko

Seiji Sakagami

Satoshi Adachi

Shu Hirata

Takanori Otsuka

Toshitaka Shimomura

Kazuhiko Kodama

Atsushi Tominaga

Tatsuhiko Matsuura

Ryuichi Koiso

Yukinari Nozawa

Emi Kaneko

Norio Masada

Ken Mizuno

A telecentric optical apparatus that is capable of suppressing an increase in the number of components as well as achieving high precision optical axis alignment, is provided. The telecentric optical apparatus of the present invention is characterized in that it is provided with: a first telecentric lens surface that is provided on an object side; a second telecentric lens surface that is provided on an image side and that shares a focus position with the first telecentric lens surface; and an optical path trimming part that is provided, between the first telecentric lens surface and the second telecentric lens surface, in an outside region, which is located on a side further out than a light passing region having a center thereof located at the focus position, and that changes an optical path such that a light beam incident on the outside region is prevented from contributing to image formation.

Telecentric optical apparatus

A scale includes a grating pattern arranged in a measurement direction. A detection head can be moved relative to the scale in the measurement direction and outputs an electric signal indicating a result of detection of the pattern. An operation unit calculates a relative displacement of the detection head relative to the scale. The detection head irradiates the scale with light. A light-receiving unit includes a light-receiving element array arranged in the measurement direction and outputs a result of detection of the irradiation light applied to the light-receiving element array as the electric signal. An optical system forms light from the scale into interference fringes on a light-receiving surface of the light-receiving unit by using lens arrays arranged in the measurement direction. A lens array pitch between neighboring lenses of the lens arrays is not equal to an integral multiple of a pitch of the grating pattern.

Encoder having light-receiving unit that includes light-receiving element array

A scale is provided with a two-level code pattern according to a pseudo random code sequence along a length measurement direction. Each code of the two-level code pattern indicates a code '1' or '0', each code includes two bits, and each bit of the two bits is L or H. The code &#x201c;1&#x201d; is represented by an A pattern which is a combination of L and H, and the code &#x201c;0&#x201d; is represented by a B pattern which is a combination of L and L or by a C pattern which is a combination of H and H. When the codes &#x201c;0&#x201d; are continued, the B pattern and the C pattern are alternately used. The scale is commonly used in a reflective type encoder or transmissive type encoder. A detection head part includes an inversion processing unit which performs inversion processing to a detection image of the scale as required.

Photoelectric encoder having a two-level code pattern using three or more bit-combination patterns

A resistor string outputs sixteen signals with a phase difference of 22.5&#xb0; by dividing voltage between two adjacent phases of a four-phase input signal with a phase difference of 2&#x3c0;/M (where M is an integer equal to or greater than 2), and by generating four signals with a delayed phase for each phase of the four-phase input signal. A switch portion selects four signals with a phase difference of 90&#xb0; from the sixteen signals. Amplifiers output each of the four signals, which are attenuated by dividing the voltage with the resistor string, as a four-phase output signal by amplifying each of the four signals such that an amplitude of the four signals matches the amplitude of the four-phase input signal.

Encoder having phase adjuster for offsetting phases of multi-phase input signal

A photoelectric encoder includes an absolute scale provided with an absolute pattern based on pseudo-random data, and a detection head including a light source that emits light to the absolute pattern of the absolute scale, and a light receiving unit that receives light from the absolute pattern, and it detects an absolute position of the detection head with respect to the absolute scale. In the photoelectric encoder, the absolute pattern is composed of a grating part and a dark part arranged in a repetitive manner. The photoelectric encoder further includes an interference pattern generation means that generates an interference pattern in combination with the grating part, and an interference pattern signal processing unit that detects the pseudo-random data of the absolute pattern based on the interference pattern received by the light receiving unit.

Photoelectric encoder having an interference pattern signal processing unit detects the pseudo-random data of the absolute pattern of an absolute scale

A semiconductor package includes a semiconductor device and a substrate, the semiconductor device including a straight line portion on an outer periphery and the substrate supporting the semiconductor device. A foil positioning pattern is formed on a front surface of the substrate, the positioning pattern touching the straight line portion of the semiconductor device to regulate a position of the semiconductor device.

Semiconductor package and method for manufacturing the same

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.

Origin location detection circuit

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 method and apparatus for suppressing loss of scale image contrast due to interference effects from optical path length differences, including lens profile aberrations, are provided in a displacement sensing optical encoder that uses a telecentric imaging configuration. According to the invention, the encoder is configured such that the image light that reaches the detector comprises symmetric ray bundles concentrated symmetrically on opposite sides of the optical axis center at the limiting aperture of the telecentric imaging configuration. Central ray bundles, and/or other ray bundles that have an optical path lengths significantly different than the operational symmetric ray bundles are prevented or blocked. As a result destructive interference is prevented and image contrast is improved.

Lens aberration correction in a doubly telecentric displacement sensor

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

A reflection type encoder, which receives a plurality of light-receiving signals from a single scale, includes a light source, a scale having a plurality of patterns formed thereon to which light is irradiated from the light source, and a light-receiving element for receiving light reflected from each of the plurality of patterns, wherein a plurality of patterns each having different thicknesses are formed on a single track of the scale by using a dielectric substance, light of a plurality of wavelengths each having different brightnesses in accordance with differences in the thickness of the dielectric substance is irradiated from the light source, and a light-receiving signal is obtained for the respective thicknesses of the dielectric substance. Therefore, the scale can be downsized by overlapping a plurality of patterns on the same track.

Reflection type encoder, scale thereof and method for producing scale

A photoelectric encoder includes: a scale having a grating formed thereon along a measuring axis; a light source operative to emit light to the scale so as to form a light spot on the grating; and a photoreceiver operative to receive reflected light from the scale. The light source and the photoreceiver are disposed so as to be allowed to move relative to the scale at least in a direction along the measuring axis. The light source emits the light to the scale so that the photoreceiver receives the reflected light by the scale. The light source emits light with different wavelengths. The scale includes a plurality of reflection portions that respectively reflect the light with different wavelengths.

Photoelectric encoder, scale and method of manufacturing scale

An optical encoder () is provided with: a light-emitting element () including a main-signal light-emitting element () having a red LED (A) that emits red light and an origin light-emitting element () having an infrared LED (A) that emits infrared light; and a receiver unit () including a main-signal photo detector () that receives the red light to generate a predetermined signal and an origin photo detector () that receives the infrared light to generate a predetermined signal. Accordingly, even when the infrared light enters the main-signal photo detector () or the red light enters the origin photo detector (), no signal is generated by the light, thereby effectively preventing crosstalk. Thus, the measurement accuracy of the optical encoder () can be improved.

Crosstalk preventing optical encoder

A three-grating type photoelectric encoder includes a second grating formed on a scale and first and third gratings disposed on a side of a detector. A part of at least the first grating is shifted in a direction of a measurement axis by P/(2n) (wherein P is a grating pitch, n is the order of a harmonic component to be removed) in order to remove a harmonic component of the nth order. This encoder can be improved with high accuracy by removing harmonic components without increasing manufacturing costs.

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Kawasaki, Japan

Toru Yaku