External optical feedback element for tuning a multi-wavelength gas laser

    公开(公告)号:US11309679B2

    公开(公告)日:2022-04-19

    申请号:US16612601

    申请日:2018-05-09

    摘要: An external optical feedback element (108) for tuning an output beam of a gas laser (102) having multiple wavelengths includes a partially reflective optical element (108) positioned on a beam path of the output beam (106) outside of an internal optical cavity of the gas laser (102), and a stage (114) to support the optical element and adjust rotation, horizontal tilt angle, and vertical tilt angle of the optical element with respect to the beam path. The output beam (106) is partially reflected at the optical element (108) and fed back into the internal optical cavity of the gas laser (102), with the intensity varying for multiple wavelengths and adjusted by changing rotation, horizontal tilt angle and vertical tilt angle of the optical element. Thereby, a variable feedback of the output beam into the internal optical cavity of the gas laser is provided, which leads to a selective output wavelength of the gas laser, either at a single line or at multiple lines simultaneously. This setup may allow to control the wavelength of a commercial CO2 gas laser without a modification of the laser itself by adding a coupled cavity with a wavelength selective element like a grating to the given gas laser resonator.

    VIAL CONTENT DETECTION USING ILLUMINATED BACKGROUND PATTERN

    公开(公告)号:US20210056660A1

    公开(公告)日:2021-02-25

    申请号:US17001149

    申请日:2020-08-24

    摘要: A machine vision system that uses an imager to capture an optical image of a target object that may contain a liquid. The target object is illuminated by an illumination source positioned oppositely from the imager and a predetermined pattern is positioned between the illumination source and the target object so that the imager will capture optical images of the background pattern through any liquid positioned in the target object. A processor is programmed to analyze captured images to detect any distortions of the pattern that are attributable to the presence of a liquid in the target object.

    Rotary position encoding using non-maximal-length pseudo-random codes

    公开(公告)号:US12085382B2

    公开(公告)日:2024-09-10

    申请号:US17674169

    申请日:2022-02-17

    发明人: Chia-Pin Liang

    IPC分类号: G01B11/26 G01D5/26

    CPC分类号: G01B11/26 G01D5/26

    摘要: A rotary position encoder includes a detection unit and a scale co-configured and co-operative to detect a relative rotational position and to generate a position output accordingly. The scale has a scale pattern according to a linear-feedback shift register (LFSR) pseudo-random code, which is a non-maximal length code having a seed value, tap positions, and modified least-significant bit position(s) of code words that satisfy rotary constraint by which each code word follows in sequence from the adjacent code word.

    ROTARY POSITION ENCODING USING NON-MAXIMAL-LENGTH PSEUDO-RANDOM CODES

    公开(公告)号:US20220260365A1

    公开(公告)日:2022-08-18

    申请号:US17674169

    申请日:2022-02-17

    发明人: Chia-Pin Liang

    IPC分类号: G01B11/26 G01D5/26

    摘要: A rotary position encoder includes a detection unit and a scale co-configured and co-operative to detect a relative rotational position and to generate a position output accordingly. The scale has a scale pattern according to a linear-feedback shift register (LFSR) pseudo-random code, which is a non-maximal length code having a seed value, tap positions, and modified least-significant bit position(s) of code words that satisfy rotary constraint by which each code word follows in sequence from the adjacent code word.

    ROTARY POSITION ENCODER BASED ON POLARIZATION

    公开(公告)号:US20220221311A1

    公开(公告)日:2022-07-14

    申请号:US17571958

    申请日:2022-01-10

    IPC分类号: G01D5/34

    摘要: A rotary optical position encoder includes a source of a linear-polarized light beam, a polarization-sensitive detector, and a rotating retarder disposed for rotation between the source and the detector. The retarder is configured and operative to produce a polarized exit beam whose polarization state rotates at a rate greater than a rotation rate of the retarder, thereby for increased resolution over a similar encoder using a rotating polarizer element. In an example, when polarized light is incident upon a rotating half-wave retarder, the transmitted beam's polarization axis rotates at twice the rate of retarder rotation, resulting in an electrical detector output that varies four times per revolution. Resolution is improved accordingly, as a given detected increment at the output is produced by only one-half the physical rotation increment required for a simple polarizer.

    Vial content detection using illuminated background pattern

    公开(公告)号:US11270402B2

    公开(公告)日:2022-03-08

    申请号:US17001149

    申请日:2020-08-24

    摘要: A machine vision system that uses an imager to capture an optical image of a target object that may contain a liquid. The target object is illuminated by an illumination source positioned oppositely from the imager and a predetermined pattern is positioned between the illumination source and the target object so that the imager will capture optical images of the background pattern through any liquid positioned in the target object. A processor is programmed to analyze captured images to detect any distortions of the pattern that are attributable to the presence of a liquid in the target object.

    Phase estimation method and apparatus therefor

    公开(公告)号:US09689717B2

    公开(公告)日:2017-06-27

    申请号:US14469753

    申请日:2014-08-27

    IPC分类号: G01D5/347 G01D5/244

    摘要: Phase estimation apparatus processes sensor signals from sensors to estimate a phase of a periodically varying state of an object, such as position of a moving object. A phase estimation processor applies a first correlation calculation to simultaneously collected samples of the sensor signals to generate first quadrature values, where the first correlation calculation employs variable calculation values, and applies a phase calculation to the first quadrature values to generate the phase estimation. A pre-quadrature calibration circuit applies respective second correlation calculations to respective sequences of samples of the sensor signals individually to generate second quadrature values for each of the sensor signals, and applies phase and/or magnitude calculations to the sets of second quadrature values to generate the variable calculation values for the first correlation calculation, thereby compensate for the error component and improve accuracy of the estimated phase.