Optical Patents (Class 341/13)
  • Publication number: 20080211694
    Abstract: A rotation-angle detecting apparatus detects a rotation angle of a rotating disc having radial markings, includes a plurality of detectors arranged at opposite sides of the axis of rotation of the disc and facing the markings, each of the detectors operable to detect a light beam from the markings, and outputting a pair of periodic signals having a 90-degree phase difference between the members of the pair; an analog-to-digital converter arranged to convert pairs of periodic signals from the detectors into pairs of digital signals; a digital signal processor configured to process the pairs of digital signals from the analog-to-digital converter; a binarization unit arranged to binarize the pairs of periodic signals from the detectors; and a counter arranged to count the pairs of periodic signals binarized by the binarization unit. The digital signal processor determines the rotation angle of the disc based on the pairs of digital signals from the analog-to-digital converter and count results from the counter.
    Type: Application
    Filed: February 13, 2008
    Publication date: September 4, 2008
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Naoki Kawamata
  • Patent number: 7417563
    Abstract: A method for determining the absolute value of a rotational angle includes imaging a continuous segment of a code track of a code carrier on a sensor array such that the sensor array generates a corresponding output signal. The code track includes a code provided over an angular range of 360°. The code contains a plurality of code words with each code word respectively corresponding to an angular value in the angular range. The output signal is correlated with a reference signal in a correlation filter to produce a correlation function signal. The reference signal is indicative of the code and the angular values corresponding to the code words. The correlation function signal is processed to determine the code word of the imaged segment of the code track as a function of the angular value where the output signal best coincides with the reference signal.
    Type: Grant
    Filed: July 6, 2006
    Date of Patent: August 26, 2008
    Assignee: Leopold Kostal GmbH & Co. KG
    Inventors: Uwe Borgmann, Michael Köster
  • Patent number: 7414238
    Abstract: An optical encoder device for a small-sized motor has a code wheel attached to a motor shaft which extends to the exterior of the motor through a bearing accommodated in a bearing-retaining section provided on an end bell of the motor, and a board on which a photosensor module is mounted such that an optical modulation track portion of the code wheel is positioned and disposed in a gap of the photosensor module. While a spacer is sandwiched between the end bell and the board, the motor, the spacer, and the board are fixed together by soldering a pair of motor terminals to a printed wiring portion of the board. The spacer has a generally U-shaped structure so as to allow fitting in position thereof from a direction orthogonal to the motor shaft.
    Type: Grant
    Filed: September 26, 2005
    Date of Patent: August 19, 2008
    Assignee: Mabuchi Motor Co., Ltd.
    Inventors: Kouhei Igarashi, Toshihiro Kamiyoshihara
  • Patent number: 7412116
    Abstract: The invention relates to an optical device, apt to generate and process optical codes at least one wavelength, comprising P inputs s, with 1?s?P, and P?1, and N outputs k, with 1?k?N and N?1, characterized in that it is apt to simultaneously generate and process Nc?2, made of C chips with time interval ?, with C?2, characterized in that the transfer function Tsk(f) from the input s to the output k satisfies the following formula: where: Fv is a transfer function of an optical filter, for v=0, 1 . . . , V?1, av is a constant value, for v=0, 1, . . . , V?1 Ssk is an integer number (Ssk?Z), Nk is a constant value, for k=2, . . . N, and V is a positive integer number with 1?V?log2N. The invention further relates to a set of optical codes, apt to be generated, in particular, by such optical device, and to networks and apparatus comprising such optical device.
    Type: Grant
    Filed: December 30, 2003
    Date of Patent: August 12, 2008
    Assignee: Universita′ Degli Studi “Roma Tre”
    Inventor: Gabriella Cincotti
  • Patent number: 7403143
    Abstract: An optical quantizing unit includes an optical divider dividing 1st optical pulses to be quantized and sending the divided 1st optical pulses into a plurality of paths; a plurality of optical filters passing with different transmittances the divided 1st optical pulses; and an optical threshold filter sequentially receiving the 1st optical pulses, and sending 2nd optical pulses when light intensities of the 1st optical pulses are above a preset threshold value.
    Type: Grant
    Filed: November 30, 2007
    Date of Patent: July 22, 2008
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masatoshi Hirono, Takahiro Suzuki, Hideki Ito, Takeshi Morino
  • Patent number: 7400269
    Abstract: An optical encoder. The optical encoder includes a coding element, an emitter, and a detector. The coding element has a track with a track pattern. The track pattern includes a plurality of optically distinguishable sections. The plurality of optically distinguishable sections includes a limit switch section. The emitter generates a light signal incident on the track of the coding element. The detector includes a limit switch photodetector positioned to detect the light signal from the emitter. The detector generates a limit switch output signal in response to the detected light signal above a limit switch threshold at the limit switch photodetector. Embodiments of this type of optical encoder implement limit switches into a single track on the coding element.
    Type: Grant
    Filed: November 9, 2006
    Date of Patent: July 15, 2008
    Assignee: Avago Technologies ECBU IP Pte Ltd
    Inventors: Weng Fei Wong, Chee Foo Lum
  • Patent number: 7397394
    Abstract: A method for determining the absolute value of a rotational angle includes imaging a continuous segment of a code track of a code carrier on a sensor array such that the sensor array generates a corresponding output signal. The code track has a light and dark transition pattern over an angular range of 360°. The sensor array output signal is subjected to a convolution operation with a reference signal in a first correlation filter to reconstruct the light and dark transition pattern of the imaged segment of the code track as a first correlation function signal. The first correlation function signal is processed to determine a code word and a predetermined angle corresponding to the code word.
    Type: Grant
    Filed: July 6, 2006
    Date of Patent: July 8, 2008
    Assignee: Leopold Kostal GmbH & Co. KG
    Inventor: Michael Köster
  • Patent number: 7391012
    Abstract: An apparatus (100) for detecting rotational angle of a rotational element (110), includes a light emitting element (1) and an image detecting element (3). The light emitting element is disposed on the rotational element to emit light. The image detecting element has a plurality of reception zones (31, 32 . . . N) for receiving the light emitted. Each of the reception zones corresponds to an angular section of the rotational element.
    Type: Grant
    Filed: April 10, 2006
    Date of Patent: June 24, 2008
    Assignee: Hon Hai Precision Industry Co., Ltd.
    Inventor: Wen-Ssu Chiu
  • Publication number: 20080111062
    Abstract: An optical encoder. The optical encoder includes a coding element, an emitter, and a detector. The coding element has a track with a track pattern. The track pattern includes a plurality of optically distinguishable sections. The plurality of optically distinguishable sections includes a limit switch section. The emitter generates a light signal incident on the track of the coding element. The detector includes a limit switch photodetector positioned to detect the light signal from the emitter. The detector generates a limit switch output signal in response to the detected light signal above a limit switch threshold at the limit switch photodetector. Embodiments of this type of optical encoder implement limit switches into a single track on the coding element.
    Type: Application
    Filed: November 9, 2006
    Publication date: May 15, 2008
    Inventors: Weng Fei Wong, Chee Foo Lum
  • Patent number: 7362242
    Abstract: A photosensor module is composed of a light-receiving element module accommodating a light-receiving element, and a light-emitting element module accommodating a light-emitting element, which modules are separate, paired components. One of the paired light-receiving element module and light-emitting element module is mounted on a printed circuit board of a board unit, which is fixed to an end surface of a motor. After a code wheel is attached and fixed to the motor shaft along the axial direction of the motor shaft, a generally L-shaped module holder, which accommodates the other of the paired light-receiving element module and light-emitting element module, is mounted to the board unit. Thus, the light-emitting element and the light-receiving element are positioned such that these elements face each other via the optical modulation track portion of the code wheel.
    Type: Grant
    Filed: December 13, 2006
    Date of Patent: April 22, 2008
    Assignee: Mabuchi Motor Co. Ltd.
    Inventors: Kouhei Igarashi, Masayuki Iida
  • Patent number: 7358865
    Abstract: An optical encoder includes a cylindrical reflective scale, a point light source for irradiating the reflective scale, and light-receiving elements for receiving the light beams reflected by the reflective scale. The pitch of the reflective scale is set to an appropriate value such that the pitch of interference fringes formed by light beams that are reflected by the reflective scale is matched to the pitch of the light-receiving elements at a position with a desired gap.
    Type: Grant
    Filed: August 28, 2006
    Date of Patent: April 15, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masahiko Igaki, Akio Atsuta
  • Patent number: 7348546
    Abstract: A position measuring system having a scale that includes an incremental graduation track, which extends in a measuring direction, the incremental graduation track having a periodic arrangement of graduation areas with different optical properties and a reference marking in a reference position, which has an aperiodic arrangement of graduation areas. A scanning unit including a light source and an opto-electronic detector arrangement having a reference pulse signal detection unit for generating a reference pulse signal. A periodic strip pattern results in a detection plane, which is amplitude-modulated in an area of the reference position, wherein the reference pulse signal detection unit includes several reference pulse signal detection elements, which create the reference pulse signal so that a periodic signal portion, as well as low-frequency signal portions are filtered out of the incremental graduation track to a large degree.
    Type: Grant
    Filed: February 9, 2006
    Date of Patent: March 25, 2008
    Assignee: Dr. Johannes Heidenhain GmbH
    Inventors: Jürgen Schoser, Michael Hermann, Wolfgang Holzapfel
  • Patent number: 7348543
    Abstract: An optical encoder assembly and a method for measuring a rotation angle in which optical beams are spread over the circumference of a rotating optical disk by means of optical guides (OG). In the preferred embodiment the rotating optical disk has a pair of concentrically arranged circular patterns with alternating transparent and opaque sections. Each beam is input via optical fibers to one of a pair of concentrically disposed OGs with a cylindrical shape (COGs) respectively and propagated through the optical disk to be reflected by a mirror with two concentrically disposed circular patterns of reflective and non reflective sections, reentering the COG through the optical disk in a reverse direction. The COGs then guide the light beams back to an electronic interface that converts the optical signals into electronic signals producing position information.
    Type: Grant
    Filed: January 15, 2004
    Date of Patent: March 25, 2008
    Assignee: Yaskawa Eshed Technologies Ltd.
    Inventor: Yves Villaret
  • Patent number: 7348547
    Abstract: There is provided a position detecting apparatus that has a high ability of detecting a correct position even if there is mechanical play in a moving mechanical member, a position of which is detected, and an image processing apparatus provided with the position detecting apparatus. In a position detecting apparatus 100 of the invention, even if there is a certain degree of play in a slide plate 11 that moves in a slide direction DN and reading by bit mark reading sensors 21 to 24 deviates from regular reading of binary numbers, since binary numbers appended to a surface of the slide plate is formed by gray codes, a position derived by a position deriving unit is more likely to be controlled to be as small as adjacent binary numbers with respect to a slide direction of the slide plate compared with the case of the conventional simple binary numbers.
    Type: Grant
    Filed: February 28, 2006
    Date of Patent: March 25, 2008
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki Kaisha
    Inventor: Masao Ando
  • Patent number: 7345597
    Abstract: A method for determining absolute value of a rotational angle includes imaging a segment of a code track onto a sensor such that the sensor generates a corresponding output signal. The track includes a code in the form of a light and dark transition pattern over an angular range. The code contains code words with each code word corresponding to a respective angular value. The code word of the imaged segment is determined from the position of the transitions in the output signal to determine the angular value of the imaged segment. The position of the transitions in the output signal is compared with a reference curve to determine position deviations between the output signal and the reference signal. The reference curve represents the transitions expected in the output signal in the absence of unwanted mechanical influences. The unwanted mechanical influences are determined as a function of the determined deviations.
    Type: Grant
    Filed: July 6, 2006
    Date of Patent: March 18, 2008
    Assignee: Leopold Kostal GmbH & Co. KG
    Inventor: Michael Koester
  • Patent number: 7329858
    Abstract: An optical encoder includes a mobile object having a plurality of aligned slits, a light-emitting portion for emitting light toward the mobile object, and a light-receiving portion 103 for receiving the light which has passed the mobile object. The light-receiving portion 103 produces an AC (Alternating Current) signal in an oscillation circuit 111 and outputs an input current, which is changed to an AC, from a light-emitting current output circuit 112 into the light-emitting portion.
    Type: Grant
    Filed: April 13, 2005
    Date of Patent: February 12, 2008
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Norikazu Okada
  • Patent number: 7305435
    Abstract: A mobile device, system, method, and software for communicating with the internet utilizing a written universal resource locator (URL). A camera unit is used to receive a raw visual light image containing a written URL, the raw visual light image is converted to an electronic image, and the device locates glyphs of at least one particular standardized set of URL characters in the electronic image, for example glyphs corresponding to www. Then the URL characters are extracted from the electronic image, the URL is sent in a request signal to a web server, and in response an internet site is presented. The mobile device includes initiation means for sending an instruction to obtain a raw visual light image that includes glyphs of at least one particular set of characters, such as www, and further includes a camera, a display, and an internet interface. The mobile device processes an electronic image signal provided by the camera, in order to obtain the web site signal from the internet interface.
    Type: Grant
    Filed: August 25, 2003
    Date of Patent: December 4, 2007
    Assignee: Nokia Corporation
    Inventor: Kimmo Hämynen
  • Patent number: 7289042
    Abstract: The invention relates to a reference mark detector for use with a metrological scale or encoder (10) having a patterned reference mark rm movable relative to the reference mark detector. The detector may comprise a photodetector array (20) for detecting the patterned reference mark, the array comprising at least two sets of detector elements A and B each set being formed as a pattern which relates to the pattern of the reference mark. The two sets may be separate rows of photodectors or different elements of the same row of photodetectors. The pattern is preferably irregular.
    Type: Grant
    Filed: July 19, 2004
    Date of Patent: October 30, 2007
    Assignee: Renishaw, PLC
    Inventor: Iain Robert Gordon-Ingram
  • Patent number: 7284921
    Abstract: A mobile device including: a printhead for printing onto a print medium, the print medium including coded data; a media path for directing the print medium past the printhead for printing; an optical sensor; a first optical pathway for directing optical image information to the sensor to enable it to read at least some of the coded data from the print medium while at least some of the print medium is within the media path; and a second optical pathway for directing optical image information to the sensor to enable it to read coded data from the print medium when the print medium is not in the media path.
    Type: Grant
    Filed: May 9, 2005
    Date of Patent: October 23, 2007
    Assignee: Silverbrook Research Pty Ltd
    Inventors: Paul Lapstun, Kia Silverbrook
  • Patent number: 7265338
    Abstract: A photoelectric encoder is provided, which emits light from a light source to a main scale and an index scale that can relatively move with respect to each other and obtains a light-receiving signal by interaction between the main scale and the index scale. The photoelectric encoder uses as the light source an incoherent semiconductor light source (white LED) in which a full width at half maximum of an emission spectrum is wider than that of a monochromatic semiconductor light source. Thus, it is possible to reduce an effect of a gap change on an output signal of the encoder and make positional adjustment easier, thereby improving misalignment characteristics.
    Type: Grant
    Filed: October 25, 2005
    Date of Patent: September 4, 2007
    Assignee: Mitutoyo Corporation
    Inventors: Tetsuro Kiriyama, Toru Yaku, Shingo Nihommori
  • Patent number: 7265339
    Abstract: An interpolating detector for generating a position signal indicating a change in the relative position of a code pattern that includes alternating light and dark stripes is disclosed. The interpolating detector includes a photodiode array, an interpolation function generator, a detector function generator, and a cross-point detector. The photodiode array includes a plurality of sets of photodetectors that generate sinusoidal signals having different amplitudes and phases. The interpolation function generator generates first and second interpolation functions, I1(x)=f1 cos(x) and I2(x)=f2 sin(x), respectively, from the photodiode signals. The detector function generator generates 4 detector signals, D1(x)-D4(x), from the photodiode signals. The cross-point detector generates a transition signal when I1(x) crosses D1 or D3 or when I2(x) crosses D2 or D4.
    Type: Grant
    Filed: May 22, 2006
    Date of Patent: September 4, 2007
    Assignee: Avago Technologies General IP (Singapore) Pte. Ltd.
    Inventors: Kean Foong Ng, Siang Leong Foo
  • Patent number: 7262714
    Abstract: An encoder having a detector and an optical system that generates an image of a code strip on the detector is disclosed. The image includes a plurality of light and dark stripes, the detector generating a plurality of sinusoidal signals differing in phase from one another as the code strip moves relative to the detector. Each sinusoidal signal cycles through one period when the code strip moves a distance equal to one light stripe and one dark stripe with respect to the detector. A frequency multiplier generates a plurality of frequency multiplied signals. The encoder utilizes a signal interpolator that defines a plurality of position locations utilizing the frequency multiplied signals, there being at least 5 such points corresponding to the code strip moving a distance equal to one light stripe and one dark stripe with respect to the detector.
    Type: Grant
    Filed: December 1, 2005
    Date of Patent: August 28, 2007
    Assignee: Avago Technologies General IP (Singapore) Pte. Ltd.
    Inventor: Siang Leong Foo
  • Patent number: 7263172
    Abstract: The invention relates to an apparatus, notably an X-ray apparatus, which comprises two components which are displaceable relative to one another. A position visualization unit is arranged on one component of the apparatus and the other component of the apparatus is provided with an image acquisition unit whose acquisition zone contains a segment of the position visualization unit which changes due to the motion. The image acquisition unit acquires images of the segment present in the acquisition zone and applies such images to an evaluation unit which extracts position information from the images.
    Type: Grant
    Filed: July 1, 2003
    Date of Patent: August 28, 2007
    Assignee: Koninklijke Philips Electronics, N.V.
    Inventor: Dieter Grünau
  • Patent number: 7256712
    Abstract: An encoder includes an encoder scale having a predetermined cyclic pattern, and at least one detection unit configured to detect a cyclic displacement according to movement of the encoder scale. The encoder further includes a signal elimination unit configured to subtract, from an output signal of the at least one detection unit, one of an entirety of a DC signal component, which is free from dependency on a relative displacement of the encoder scale, and a signal component that is proportional to the DC signal component.
    Type: Grant
    Filed: November 30, 2005
    Date of Patent: August 14, 2007
    Assignee: Olympus Corporation
    Inventor: Hiromasa Fujita
  • Patent number: 7245233
    Abstract: A light receiving device is disclosed that is able to reduce jitter and to improve detection resolution. The light receiving device has plural light receiving elements each having a rectangular light receiving area. The light receiving areas are connected to each other at vertices on diagonals thereof, and sides of the light receiving areas of neighboring light receiving elements are adjacent to each other.
    Type: Grant
    Filed: March 28, 2006
    Date of Patent: July 17, 2007
    Assignee: Mitsumi Electric Co., Ltd.
    Inventors: Hideaki Sannomiya, Naosumi Waki, Yuko Kimura, Junichiro Tanaka
  • Patent number: 7233261
    Abstract: A microwave frequency deflection cell analog to digital converter is provided. The phase velocity of an optical wave is effectively reduced to that of a microwave frequency electro-magnetic signal in an optical deflector. The electro-optic effect is used for a controlled deflection of an optical beam. The angle of beam deflection varies in accordance with an applied voltage, which may be a signal in the microwave frequency range. A device of the invention includes a birefringent crystal having transmission line conductors arranged to create an electric field in the crystal in response to an applied voltage, and mirrors arranged to create a multi-bounce path through the crystal for a light beam directed into the crystal on an entrance path that is non parallel to the mirrors. The multi-bounce path effectively slows the velocity of the optical wave to that of the voltage wave, permitting deflection or modulation of the beam by microwave frequency electrical signals.
    Type: Grant
    Filed: September 24, 2004
    Date of Patent: June 19, 2007
    Assignee: The Curators of the University of Missouri
    Inventors: William Nunnally, John Gahl, Timothy Renkoski
  • Patent number: 7231293
    Abstract: The present invention provides a method and assembly which determines a route using a computer system, a map and a user operated sensing device. The map shows a geographic area and includes coded data that is indicative of the map and reference points on the map. The sensing device is operable to sense the coded data and generate indicating data relating to the map's identity and one or more of the reference points. The computer system is operable to identify a geographic location from the indicating data. The sensing device is positioned relative to the map to generate indicating data specifying a point on the route, and the indicating data is sent to the computer system for it to determine a route incorporating the specified point.
    Type: Grant
    Filed: October 28, 2004
    Date of Patent: June 12, 2007
    Assignee: Silverbrook Research Pty Ltd
    Inventors: Paul Lapstun, Jacqueline Anne Lapstun, Kia Silverbrook
  • Patent number: 7227125
    Abstract: An encoder device includes a first array that includes first through fourth photodiodes adjacent to each other in an X direction, each having a length of X1; a second array that includes fifth through eighth photodiodes adjacent to each other in the X direction, each having a length of X1, and is adjacent to the first array in a Y direction but displaced by X1/2 in the X direction relative to the first array; a slit member that includes light transmitting sections and light shielding section arranged alternately, each having a length 2×X1, and is movable in the X direction; and a logic circuit that generates first and second detection signals from output signals of the first through fourth photodiodes and output signals of the fifth through eighth photodiodes, respectively, a phase of the second detection signal being shifted by a ¼ period of the first detection signal relative to the first detection signal.
    Type: Grant
    Filed: March 30, 2006
    Date of Patent: June 5, 2007
    Assignee: Mitsumi Electric Co., Ltd.
    Inventors: Hideaki Sannomiya, Naosumi Waki, Junichiro Tanaka
  • Patent number: 7223963
    Abstract: An optical encoder comprising a light-receiving part having photodiodes equal in number to the common multiplier of a number of slits facing the light-receiving part and a number of movement information signals. Output terminals of the photodiodes are connected so that the movement information signals are respectively obtained by adding output signals of the plurality of photodiodes out of the photodiodes equal in number to the common multiplier. The twelve photodiodes are balancedly arranged corresponding to three slits and a light-receiving area of each photodiode is made smaller by subdiving each photodiode. The optical encoder suppress difference, distortion and variance of the movement information signals or the like obtained from the light-receiving part with the result that accurate movement information is obtained.
    Type: Grant
    Filed: August 5, 2004
    Date of Patent: May 29, 2007
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Norikazu Okada, Hirohisa Warita, Hiroki Nakamura, Kazufumi Oki
  • Patent number: 7217916
    Abstract: In an optical encoder, a plurality of light sources is controlled on and off so as to use light rays to irradiate an optical grating of a scale from a plurality of different directions. The light rays are received by a plurality of photoreceptor elements. Operations are performed using signals output from the photoreceptor elements. Accordingly, the relative position between the photoreceptor elements and the scale is detected precisely.
    Type: Grant
    Filed: February 20, 2004
    Date of Patent: May 15, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akio Atsuta, Masahiko Igaki
  • Patent number: 7215112
    Abstract: A non-contact linear absolute position sensor includes a first magnetic encoder having n+1 pole pairs, a second magnetic encoder having n pole pairs and located and aligned with the first magnetic encoder so as to cover a linear distance. The magnetic encoders are affixed to a traveling body. Two pairs of Hall Effect sensors are located near each of the first and second magnetic encoders and are configured to generate linear position signals. A processor is provided to process the linear position signals to generate an output signal indicative of a linear absolute position of the traveling body.
    Type: Grant
    Filed: November 7, 2005
    Date of Patent: May 8, 2007
    Assignee: Delphi Technologies, Inc.
    Inventors: Mario A. Recio, Arquimedes Godoy, Daniel A. Martinez
  • Patent number: 7214930
    Abstract: A pulse generator which can be used for a printer, for example an ink jet printer, to provide adjustable pulses per unit displacement or speed has a linearly or rotatably displaceable first plate with a periodic pattern of different optical density or transmissivity or reflectivity juxtaposed with a second plate with another array of markings of different optical density transmissivity or reflectivity so that in an overlapping region a Moiré pattern or other interference pattern for beat pattern is provided. The latter is detected by an optical sensor which outputs electrical pulses. The two plates can be relatively displaced to change the pattern and hence the detected periodicity.
    Type: Grant
    Filed: October 28, 2004
    Date of Patent: May 8, 2007
    Assignee: KBA-Metronic AG
    Inventor: Peter Schmitt
  • Patent number: 7199355
    Abstract: In a method according to the invention for the accurate determination of an angle of rotation (w) about an axis (a), at least a part of a plurality of pattern elements (5, ..., 13) arranged around a pattern center (4), a multiplicity of which are arranged one behind the other in a rotation, is at least partly focused by optical beams on a multiplicity of detector elements (2) of an optical detector (1) which are arranged in series. The pattern elements (5, ..., 13) are arranged on a rotating body (3) which is connected to the detector (1) so as to be rotatable about the axis (a). Positions (p) of the focused pattern elements are resolved by the detector elements (2) of one and the same detector (1). In a first step, effects of an eccentricity (e) of the pattern center (4) relative to the axis (a) on the determination of an angle of rotation are computationally determined from resolved positions (p) of at least one pattern element (5, ..., 13).
    Type: Grant
    Filed: August 31, 2005
    Date of Patent: April 3, 2007
    Assignee: Leica Geosystems AG
    Inventor: Heinz Lippuner
  • Patent number: 7199354
    Abstract: A photodiode detector array for optical encoders includes a plurality of photodiodes, each of the photodiodes providing a scanning signal with a defined phase relationship to a scale when the detector array moves relative to the scale. A plurality of switching elements is provided for selectively combining each of the photodiodes with other photo diodes in a defined manner. The switching elements allow the photodiodes to be unambiguously combined for at least two different scale radii so that a defined number of phase shifted scanning signals is generated in each case. The combination of the photodiodes differs between the at least two different scale radii.
    Type: Grant
    Filed: August 26, 2004
    Date of Patent: April 3, 2007
    Assignees: Dr. Johannes Heidenhain GmbH, Renco Encoders, Inc.
    Inventors: Elmar Mayer, Ruth E. Franklin
  • Patent number: 7196320
    Abstract: A passive all fiber optic encoder that will be able to determine speed, position, and direction of movement of a movable object. The all passive encoder utilizes no electronics within the sensing part and therefore is deployable in harsh environments, electrical, electromagnetic and radiation fields, otherwise not possible with conventional electronic encoders. The system utilizes a multiwavelength light source and one optical fiber leading to the encoder sensor housing which has a shutter, a light filter assembly and reflective mirror. The movement of the shutter produces a sequential series of light impulses sequenced proportional to the movement of the shutter. The light filter assembly utilizes a minimum of two different filters each of which passes or rejects light within a certain space and wavelength range.
    Type: Grant
    Filed: March 14, 2005
    Date of Patent: March 27, 2007
    Inventor: Robert Rickenbach
  • Patent number: 7193534
    Abstract: The invention provides an interpolation apparatus for improving the resolution of an optical encoder. The optical encoder outputs an encoding signal, and the encoding signal corresponds to a first resolution. The interpolation apparatus comprises a comparing circuit and a lookup table circuit. The comparator receives the encoding signal and produces a plurality of comparison signals. The lookup table circuit receives a plurality of comparison signals and produces an outputted signal, wherein the outputted signal corresponds to second resolution. The second resolution is greater than the first resolution.
    Type: Grant
    Filed: October 20, 2005
    Date of Patent: March 20, 2007
    Assignee: BenQ Corporation
    Inventor: Hao-Feng Hung
  • Patent number: 7190752
    Abstract: The scale and complexity of an apparatus is reduced by omitting a clock extraction section. The apparatus includes: a sampling pulse train generation device which generates an optical or electrical sampling pulse train, independently of an input optical or electrical data signal with a bit rate f0(bit/s), and which has a repetition frequency f1(Hz); a data signal sampling device which samples the data signal in accordance with the sampling pulse train to obtain a sampled signal; a voltage retaining device which converts the sampled signal, and stores pieces of electrical digital data; an electrical signal processing device which reads the digital data at once or sequentially to obtain a signal eye-diagram and evaluates optical data signal quality parameters; and a trigger signal generation device which applies triggers indicating the start/finish of data acquisition and data read to the voltage retaining device and the electrical signal processing device, respectively.
    Type: Grant
    Filed: May 9, 2003
    Date of Patent: March 13, 2007
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Ippei Shake, Hidehiko Takara
  • Patent number: 7186969
    Abstract: 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.
    Type: Grant
    Filed: March 19, 2004
    Date of Patent: March 6, 2007
    Assignee: Mitutoyo Corporation
    Inventors: Toshitaka Shimomura, Shingo Nihommori, Miyako Mizutani, Eric Herbert Altendorf, Joseph Daniel Tobiason
  • Patent number: 7183536
    Abstract: A motion encoder for use with a rotating key. The motion encoder allows the direction of rotation to be determined by providing elements having different characteristics for the transmission of a IR beam. These elements are arranged in a pattern that allows an IR beam impinging on the elements to trace a path detected as the rotating key turns. The beam being detected after changes in the reflected or transmitted beam indicating the direction of rotation of the beam.
    Type: Grant
    Filed: August 1, 2003
    Date of Patent: February 27, 2007
    Assignee: Nokia Corporation
    Inventors: Gary Wingett, Andrew Raymond Bick, Maysara Fermawi
  • Patent number: 7180430
    Abstract: A Low-Cost Absolute Linear Optical Encoder (“LALOE”) for determining the absolute position of a read-head within the LALOE relative to a codestrip is disclosed. The LALOE may include an emitter module within the read-head, the emitter module having a plurality of light sources arranged in an light source pattern and a 90° Out-Of-Phase light source; and a detector module within the read-head, the detector module having a plurality of photo-detectors arranged in a photo-detector pattern corresponding to the light source pattern and a 90° Out-Of-Phase photo-detector corresponding to the 90° Out-Of-Phase light source.
    Type: Grant
    Filed: November 1, 2004
    Date of Patent: February 20, 2007
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.
    Inventors: Kean Foong Ng, Hock Aun Tan, Moon Leong Low, Yee Loong Chin
  • Patent number: 7166833
    Abstract: A system and method for determining the absolute position of a linear or rotary actuator. A code plate having a series of digital words thereon is associated with the linear or rotary actuator. Each of the digital words consists of a plurality of bits, each bit consisting of a series of parallel encoder elements, each in the shape of a wedge. One or two optical sensor heads would be used in conjunction with a signal processor to determine the exact position of the code plate, and, in turn, the linear or rotary actuator. The exact position of each of the sensor heads with respect to the code plate is determined based upon the value of optical signals reflected off of the wedge-shaped elements and detected by each of the optical sensors.
    Type: Grant
    Filed: October 7, 2004
    Date of Patent: January 23, 2007
    Assignee: Optelecom-NKF
    Inventor: Ronald H. Smith
  • Patent number: 7146072
    Abstract: Exemplary embodiments of some aspects of the invention provide an optical decoding device including: a splitting device having first, second, and third, terminals; a nonlinear element; and an attenuator, wherein the second and third terminals are associated with an optical loop including the attenuator and the nonlinear element, the nonlinear element being displaced from a mid-point of the optical loop, and wherein the decoding device is able to receive multiple encoded signals via the first terminal, to decode at least one of the encoded signals and to provide a decoded signal at the first terminal in response to the at least one encoded signal. Exemplary embodiments of further aspects of the invention provide an optical code responsive device for decoding optical encoded signals, codes, and/or symbols, for header processing, for header reading, for address decoding and/or for optical packet routing.
    Type: Grant
    Filed: June 21, 2004
    Date of Patent: December 5, 2006
    Assignee: Main Street Ventures, LLC
    Inventors: Arie Shahar, Eldan Halberthal
  • Patent number: 7132647
    Abstract: A main scale of an optical displacement measuring apparatus has slits arranged on it at regular intervals, a part of which is a missing slit that does not allow light to pass through used for detecting the original point. An index scale has four sets of windows formed on it. The four windows are arranged with mutual phase differences of ¼ P, where P is the pitch of the arrangement of the slits. When a part of the missing slit overlaps with the index scale, no light reaches to photodiodes from the missing slit and only a partial light flux passes through a window, so that the light quantity decreases. An original point signal associated with the missing slit can be obtained by adding up the outputs of all the photodiodes.
    Type: Grant
    Filed: March 9, 2005
    Date of Patent: November 7, 2006
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akio Atsuta, Masahiko Igaki
  • Patent number: 7126107
    Abstract: An encoder and related methods for use in a printing device indexing system are provided. In some embodiments, the system comprises a feedroller or other component configured to index media through a printing device, and an encoder disk is coupled to the feedroller. In these embodiments, the system includes a reflective optical detector having a transmitter and a receiver provided adjacent a first surface of the encoder disk, the reflective optical detector being configured to detect the passage of the home position mark as the encoder disk rotates by the reflection of radiation off of the first surface. Also provided in some embodiments are methods for setting a counter to correspond with the home position of a rotatable element by utilizing threshold signal levels.
    Type: Grant
    Filed: March 14, 2003
    Date of Patent: October 24, 2006
    Assignee: Lexmark International, Inc.
    Inventors: Adam J. Ahne, Alexander L. Chapman, Patrick L. Kroger, Jay W. Vessels
  • Patent number: 7106888
    Abstract: A method of enabling user interaction with computer software running in a computer system via an interface surface and a sensing device. The interface surface contains information relating to the computer software and coded data indicative of a signature field relating to the computer software. When the sensing device is placed in an operative position relative to the interface surface, it senses indicating data indicative of the signature field. The sensing device also generates movement data indicative of the sensing device's movement. The indicating data and the movement data are received from the sensing device, and the signature field is identified. Once the signature has been identified, the computer software is operated in reliance on the movement data, and in accordance with instructions associated with the signature field.
    Type: Grant
    Filed: May 23, 2000
    Date of Patent: September 12, 2006
    Assignee: Silverbrook Research PTY LTD
    Inventors: Kia Silverbrook, Paul Lapstun
  • Patent number: 7105801
    Abstract: An actuator comprising a motor for rotating a shaft connected via a gear train to an output device; an interrupter vane connected to the output device and adapted to travel in a path corresponding to the movement of the output device; and at least two interrupter switches, such as opto-interrupter switches, spaced apart from one another along the path of the interrupter vane at locations corresponding to travel limits of the output device. A controller energizes the motor in response to a command signal and de-energizes the motor in response to an indication from one of the interrupter switches that the output device is at or approaching one of the travel limits. The actuator may be a rotary or linear actuator, and may be particularly well-suited for avionics applications.
    Type: Grant
    Filed: April 2, 2004
    Date of Patent: September 12, 2006
    Assignee: ITT Manufacturing Enterprises, Inc.
    Inventors: Andrew Daniel Campany, Brian John Roth, David Brian Welch
  • Patent number: 7099070
    Abstract: Working with an information system operating an application—are an imager, a coded data source, and a computer-readable signal-bearing medium signal (FIG. 1, 11, 12, 13, 14, 15, 16, 17, 18, 21, 22, 23, 24, 25, 26, 27, 31, 32, 33, 41, 42, 43, 44, 45, 51, 52, 53, 54, 55, 91, 92, 93) connected to the information system where light from the data source—which represents data—is detected by the imager which inputs a signal—which represents the light—to the information system; where a use component of the medium causes the data to be made available to the application with the application being specified by the data; and where: the image can be from a plurality of imagers signal connected to the information system; the coded data source can be from a plurality of coded data sources; the application can be from a plurality of applications operated by the information system; and the medium can have a plurality of components which cause uses of data, management of imagers, and output signals.
    Type: Grant
    Filed: December 10, 2001
    Date of Patent: August 29, 2006
    Inventor: Leonard Reiffel
  • Patent number: 7091884
    Abstract: A position-measuring circuit is described for use with an analog position encoder of the kind comprising a code member and at least two sensors for sensing successive marks on the code member during relative movement between the code member and sensors, the sensors providing two oscillating quadrature signals. The circuit comprising means for obtaining a relatively coarse measure of position by detecting successive instants t0–t3 at which the amplitudes of the sensor signals are equal or at which the amplitude of one signal is equal to the inverse of the amplitude of the other signal. The amplitude of one of the signals or its inverse is stored at each detection instant to alternately establish relatively high and low threshold levels. A fine measure of position at an arbitrary instant T is obtained as a function of the instantaneous amplitude P of one of the signals and the difference between neighbouring high and low thresholds levels.
    Type: Grant
    Filed: September 23, 2004
    Date of Patent: August 15, 2006
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventor: Jose M. Rio Doval
  • Patent number: 7060969
    Abstract: Three rotation sensors circumferentially arranged at 90 degree intervals in a disk code wheel attached to a motor's output shaft respectively output a signal corresponding the rotational speed of the wheel. An error component of one period (one-periodic component) or an error component of two period (two-periodic component) is generated per rotation when the code wheel is eccentric to the output shaft or is elliptically deformed, respectively. Control means averages the signals of the first and second sensors to obtain a first correction signal and subtracts the signal of the third sensor from the signal of the first sensor to obtain a second correction signal while removing the two-periodic component. The control means subtracts or adds the first correction signal relative to the second correction signal upon coinciding these signals in phase and amplitude to calculate a rotation measurement signal from which the periodic components are removed.
    Type: Grant
    Filed: November 9, 2004
    Date of Patent: June 13, 2006
    Assignee: Asmo Co., Ltd.
    Inventors: Haruhiko Uchiyama, Hidehiko Natsume
  • Patent number: 7060968
    Abstract: The present invention presents an optical encoder with increased conversion rates. Improvement in the conversion rate is a result of combining changes in the pattern recognition encoder's scale pattern with an image sensor readout technique which takes full advantage of those changes, and lends itself to operation by modern, high-speed, ultra-compact microprocessors and digital signal processors (DSP) or field programmable gate array (FPGA) logic elements which can process encoder scale images at the highest speeds. Through these improvements, all three components of conversion time (reciprocal conversion rate)—namely exposure time, image readout time, and image processing time—are minimized.
    Type: Grant
    Filed: June 4, 2003
    Date of Patent: June 13, 2006
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventor: Douglas B. Leviton