Prof. Toru Yoshizawa Profile

Prof. Toru Yoshizawa

SPIE Involvement:

Conference Chair | Editor | Author

Publications (101)

Proceedings Article | 27 October 2021 Paper

3D profile measurement of openings with optical caliper

Lianhua Jin, Takuma Ashizawa, Toru Yoshizawa

Proceedings Volume 11927, 119270A (2021) https://doi.org/10.1117/12.2616254

Read Abstract +

Proceedings Article | 10 October 2020 Presentation + Paper

Optical profilometry of cylindrical openings for transparent objects

Lianhua Jin, Takumi Mukai, Toru Yoshizawa

Proceedings Volume 11552, 115520M (2020) https://doi.org/10.1117/12.2575305

KEYWORDS: Beam shaping, Optical testing, Image sensors, Light scattering, Opacity, Translucency, Sensors, Reflection, Laser scattering, Scattering

Read Abstract +

Proceedings Article | 2 November 2018 Paper

Dimensional measurement of internal profile using the optical caliper

Lianhua Jin, Nobuto Miyatsu, Eiichi Kondoh, Bernard Gelloz, Naobumi Kanazawa, Toru Yoshizawa

Proceedings Volume 10819, 108190K (2018) https://doi.org/10.1117/12.2501027

KEYWORDS: Geometrical optics, Image filtering, Optical testing, Image processing, Optics manufacturing, Optical instrument design

Read Abstract +

Proceedings Article | 13 November 2014 Paper

Compact camera for 3D position registration of cancer in radiation treatment

Toshitaka Wakayama, Shun Hiratsuka, Yoshihisa Kamakura, Katsumasa Nakamura, Toru Yoshizawa

Proceedings Volume 9276, 92760G (2014) https://doi.org/10.1117/12.2072170

KEYWORDS: 3D metrology, Cancer, Fringe analysis, Stereoscopic cameras, Cameras, Oncology, Radiotherapy, Semiconductor lasers, Mirrors, Projection systems

Read Abstract +

Proceedings Article | 28 May 2014 Paper

Optical center alignment technique based on inner profile measurement method

Toshitaka Wakayama, Toru Yoshizawa

Proceedings Volume 9110, 91100I (2014) https://doi.org/10.1117/12.2050892

KEYWORDS: Optical alignment, Ellipsometry, CCD cameras, Semiconductor lasers, Optics manufacturing, Mirrors, Receivers, Beam shaping, Spindles, Inspection

Read Abstract +

SPIE Journal Paper | 9 April 2014 Open Access

High-speed three-dimensional shape measurements using multiwavelength spatiotemporal phase shifting

Toshitaka Wakayama, Toru Yoshizawa

OE, Vol. 53, Issue 11, 112207, (April 2014) https://doi.org/10.1117/12.10.1117/1.OE.53.11.112207

KEYWORDS: 3D metrology, Phase shifts, Fringe analysis, Phase shifting, Projection systems, Semiconductor lasers, Digital Light Processing, Cameras, Mirrors, RGB color model

Read Abstract +

DOWNLOAD PAPER

Proceedings Article | 27 September 2013 Paper

Evaluation of Mueller matrix of achromatic axially symmetric wave plate

Toshitaka Wakayama, Kazuki Komaki, Israel Vaughn, J. Scott Tyo, Yukitoshi Otani, Toru Yoshizawa

Proceedings Volume 8873, 88730P (2013) https://doi.org/10.1117/12.2023849

KEYWORDS: Wave plates, Polarization, Polarizers, Silica, Polarimetry, Reflection, Polishing, Biomedical optics, Dispersion, Optical components

Read Abstract +

Proceedings Article | 6 September 2013 Paper

Uni-axial inner profile measurement

Toshitaka Wakayama, Toru Yoshizawa

Proceedings Volume 8839, 88390L (2013) https://doi.org/10.1117/12.2023473

KEYWORDS: Mirrors, Beam shaping, Charge-coupled devices, CCD cameras, Optical fibers, 3D metrology, Semiconductor lasers, Light sources, Beam splitters, Polarizers

Read Abstract +

Proceedings Article | 25 June 2013 Paper

State of the art of compact optical 3D profile measurement apparatuses: from outer surface to inner surface measurement

Toru Yoshizawa, Toshitaka Wakayama

Proceedings Volume 8769, 87691G (2013) https://doi.org/10.1117/12.2021094

KEYWORDS: Mirrors, Microelectromechanical systems, 3D metrology, Cameras, Optical fibers, Semiconductor lasers, CCD cameras, Projection systems, Collimation, Optical testing

Read Abstract +

Proceedings Article | 20 November 2012 Paper

Small size probe for inner profile measurement of pipes using optical fiber ring beam device

Toshitaka Wakayama, Kizuku Machi, Toru Yoshizawa

Proceedings Volume 8563, 85630L (2012) https://doi.org/10.1117/12.999878

KEYWORDS: Mirrors, Optical fibers, Charge-coupled devices, Indium nitride, Collimators, Inspection, Ions, Cameras, Optical testing, 3D metrology

Read Abstract +

Proceedings Article | 13 September 2012 Paper

An interferometric observation of topological effect by novel axially symmetrical wave plate

Toshitaka Wakayama, Yukitoshi Otani, Toru Yoshizawa

Proceedings Volume 8493, 849306 (2012) https://doi.org/10.1117/12.930456

KEYWORDS: Polarization, Spiral phase plates, Optical vortices, Wave plates, Polarizers, Interferometry, Silica, Polymethylmethacrylate, Optical components, Manufacturing

Read Abstract +

SPIE Journal Paper | 31 January 2012

Compact camera for three-dimensional profilometry incorporating a single MEMS mirror

Toshitaka Wakayama, Toru Yoshizawa

OE, Vol. 51, Issue 1, 013601, (January 2012) https://doi.org/10.1117/12.10.1117/1.OE.51.1.013601

KEYWORDS: Mirrors, Microelectromechanical systems, Cameras, Stereoscopic cameras, Semiconductor lasers, Projection systems, LCDs, 3D metrology, CCD cameras, Calibration

Read Abstract +

Proceedings Article | 14 September 2011 Paper

Development of a probe for inner profile measurement and flaw detection

Toru Yoshizawa, Toshitaka Wakayama, Yoshihisa Kamakura

Proceedings Volume 8133, 81330D (2011) https://doi.org/10.1117/12.893463

KEYWORDS: Inspection, Mirrors, Cameras, Glasses, Optical components, Defect inspection, Semiconductor lasers, Prisms, Optical testing, CCD cameras

Read Abstract +

Proceedings Article | 10 September 2011 Paper

Color pattern projection method for three-dimensional measurement

Toshitaka Wakayama, Toru Yoshizawa

Proceedings Volume 8133, 81330A (2011) https://doi.org/10.1117/12.894183

KEYWORDS: 3D metrology, Microelectromechanical systems, Mirrors, Cameras, Semiconductor lasers, Image sensors, Projection systems, Time metrology, Digital micromirror devices, Stereoscopic cameras

Read Abstract +

Proceedings Article | 11 November 2010 Paper

A palm-top camera for 3D profilometry incorporating a MEMS scanner

T. Yoshizawa, T. Wakayama

Proceedings Volume 7855, 78550D (2010) https://doi.org/10.1117/12.870827

KEYWORDS: Cameras, Microelectromechanical systems, 3D metrology, 3D scanning, Semiconductor lasers, Laser scanners, Stereoscopic cameras, Image sensors, Scanners, Mirrors

Read Abstract +

Proceedings Article | 11 November 2010 Paper

Development of an inner profile measurement instrument using a ring beam device

T. Yoshizawa, T. Wakayama

Proceedings Volume 7855, 78550B (2010) https://doi.org/10.1117/12.870825

KEYWORDS: Mirrors, Cameras, Glasses, Inspection, Semiconductor lasers, Optical components, Medicine, CCD cameras, CMOS cameras, Dentistry

Read Abstract +

Inner profile measurement is an important matter in such fields as medicine, dentistry and anthropology as well as mechanical engineering and other industrial applications. Here we describe recent development of our measurement principle for inner diameter of pipes and/or holes. The key device in this technique is a ring beam device which consists of a conical mirror and a laser diode. And the fundamental principle is based on optical sectioning without using any contact type stylus. The optically sectioned profile of an inner wall of a pipe-like object is analyzed to give the inner profile in addition to the inner diameter. This optical instrument with a simple and small configuration is now under development for practical uses. In our hitherto trial experimental works, the availability of this instrument has been evaluated in many cases and availability for practical applications is expected, especially, for measurement and inspection of mechanical components and elements besides pipes. This ring beam device consisting of a conical mirror and a LD is assembled to form a disk-like light sheet. We show measurement result of pipes and holes, and, at the same time, report a compact inner profile measuring instrument at this point. Both the ring beam device and a miniaturized CCD camera are fabricated into a glass tube. Availability of this instrument is shown by measuring the inner profiles of various pipes. In response to this trial, there appeared a strong request that not only the internal but external profiles should be measured simultaneously. Therefore we propose potentially possible method for measurement of external profile at the same time with internal profile. If one pair of concave mirrors are used in our arrangement, external profile is captured. In combination with inner profile measurement technique, simultaneous measurement of inner and outer profiles becomes attainable. A measurement result on a bevel gear shows availability of here proposed principle. In addition, we are trying to extend our technique to check defects and/or flaws on the inner wall of pipe-like objects.

Proceedings Article | 11 November 2010 Paper

Spectroscopic topological Stokes polarimeter

Toshitaka Wakayama, Yukitoshi Otani, Toru Yoshizawa

Proceedings Volume 7855, 785504 (2010) https://doi.org/10.1117/12.871805

KEYWORDS: Polarimetry, Polarization, Spectroscopy, Wave plates, Polarizers, Birefringence, Light sources, Charge-coupled devices, Optical alignment, Spiral phase plates

Read Abstract +

Proceedings Article | 3 August 2010 Paper

Uni-axial measurement of three-dimensional surface profile by liquid crystal digital shifter

Yukitoshi Otani, Fumio Kobayashi, Yasuhiro Mizutani, Shuugo Watanabe, Manabu Harada, Toru Yoshizawa

Proceedings Volume 7790, 77900A (2010) https://doi.org/10.1117/12.861561

KEYWORDS: 3D metrology, Liquid crystals, Distance measurement, Phase shifting, CCD cameras, Microscopes, Lens design, Bessel functions, Phase shifts, Calibration

Read Abstract +

Proceedings Article | 24 November 2009 Paper

Measurement of inner and/or outer profiles of pipes using ring beam devices

T. Wakayama, T. Yoshizawa

Proceedings Volume 7513, 751306 (2009) https://doi.org/10.1117/12.838194

KEYWORDS: Mirrors, Cameras, Glasses, Inspection, Optical components, Semiconductor lasers, CMOS cameras, Refractive index, Medicine, Dentistry

Read Abstract +

Inner profile measurement is an important matter in such fields as medicine, dentistry and anthropology as well as mechanical engineering and industry. Here we propose a measurement method for inner diameter of pipes and/or holes. The key device in this technique is a ring beam device which consists of a conical mirror and a laser diode. And the fundamental principle is based on optical sectioning without any contact probe. The optically sectioned profile of an inner wall of a pipe-like object is analyzed to give the inner profile in addition to the inner diameter. This optical instrument with a simple and small configuration is now under development for practical uses. In the hitherto-tried experimental works, the availability of this instrument has been highly evaluated and usability for practical applications is expected, especially, for measurement and inspection of mechanical components and elements besides pipes. This ring beam device consisting of a conical mirror and a LD is assembled to form a disklike light beam sheet. We show measurement result of pipes and holes, and, at the same time, report a compact inner profile measuring instrument. Both the ring beam device and a miniaturized CCD camera are fabricated in a glass tube. Availability of this instrument is shown by measuring the inner profiles of various pipes. In response to this trial, there appeared a strong request that not only the internal but external profiles should be measured simultaneously. Therefore we propose an improved method for measuring the external profile in addition to the internal profile. In our arrangement, one pair of concaved conical mirrors is used for the external profile measurement. In combination with the inner profile measurement technique, simultaneous measurement of the inner and outer profiles becomes attainable. A measurement result on a bevel gear shows availability of newly proposed principle. Now we are aiming to realize simultaneous measurement of the internal and external profiles of various types of pipes and similar objects.

Proceedings Article | 24 November 2009 Paper

Compact camera system for 3D profile measurement

Toru Yoshizawa, Toshitaka Wakayama

Proceedings Volume 7513, 751304 (2009) https://doi.org/10.1117/12.838298

KEYWORDS: Microelectromechanical systems, Mirrors, 3D metrology, Stereoscopic cameras, Cameras, Phase shifts, Imaging systems, Projection systems, Scanners, Liquid crystals

Read Abstract +

Proceedings Article | 10 September 2009 Paper

Three-dimensional profilometry system incorporating a MEMS scanner

Toru Yoshizawa, Toshitaka Wakayama

Proceedings Volume 7432, 74320P (2009) https://doi.org/10.1117/12.825980

KEYWORDS: Microelectromechanical systems, Mirrors, 3D scanning, 3D metrology, Projection systems, Laser scanners, Scanners, Imaging systems, Stereoscopic cameras, Cameras

Read Abstract +

Proceedings Article | 10 September 2009 Paper

Three-dimensional profilometry based on focus method by projecting LC grating pattern

Yukitoshi Otani, Fumio Kobayashi, Yasuhiro Mizutani, Toru Yoshizawa

Proceedings Volume 7432, 743210 (2009) https://doi.org/10.1117/12.827028

KEYWORDS: Liquid crystals, 3D metrology, Phase shifting, Distance measurement, Phase shifts, Liquids, Optics manufacturing, Microscopes, Liquid lenses, Bessel functions

Read Abstract +

Proceedings Article | 12 August 2009 Paper

Axisymmetrical Mueller matrix polarimeter

Toshitaka Wakayama, Yukitoshi Otani, Toru Yoshizawa

Proceedings Volume 7461, 74610M (2009) https://doi.org/10.1117/12.826678

KEYWORDS: Polarimetry, Sensors, Polarization, Modulation, Polarizers, Wave plates, CCD image sensors, CCD cameras, Mirrors, Axicons

Read Abstract +

Proceedings Article | 17 November 2008 Paper

Generation of vortex spectra based on geometric phase for optical tweezers

Toshitaka Wakayama, Yukitoshi Otani, Toru Yoshizawa

Proceedings Volume 7266, 72660A (2008) https://doi.org/10.1117/12.817387

KEYWORDS: Optical tweezers, Spatial light modulators, Polarizers, Polarization, Wave plates, Spiral phase plates, Geometrical optics, Particles, Dielectric polarization, Light sources

Read Abstract +

Proceedings Article | 29 August 2008 Paper

Simultaneous measurement of internal and external profiles using a ring beam device

Toshitaka Wakayama, Toru Yoshizawa

Proceedings Volume 7066, 70660D (2008) https://doi.org/10.1117/12.794388

KEYWORDS: Mirrors, Cameras, 3D metrology, Inspection, Beam shaping, Glasses, Semiconductor lasers, CCD cameras, Precision measurement, Optical testing

Read Abstract +

Proceedings Article | 11 August 2008 Paper

Moiré topography using a liquid-crystal-grating based frequency modulation technique

Fumio Kobayashi, Yukitoshi Otani, Toru Yoshizawa

Proceedings Volume 7063, 70630O (2008) https://doi.org/10.1117/12.798147

KEYWORDS: Liquid crystals, Frequency modulation, Binary data, CCD cameras, Moire patterns, Lenses, Light sources, Phase shifts, 3D metrology, Modulation

Read Abstract +

Proceedings Article | 10 October 2007 Paper

Development of a compact inner profile measuring instrument

T. Wakayama, H. Takano, T. Yoshizawa

Proceedings Volume 6762, 67620D (2007) https://doi.org/10.1117/12.733215

KEYWORDS: Cameras, Glasses, Mirrors, Inspection, Optical components, Semiconductor lasers, Refractive index, Calibration, Error analysis, CMOS sensors

Read Abstract +

Proceedings Article | 10 October 2007 Paper

Applications of a MEMS scanner to profile measurement

Toru Yoshizawa, Toshitaka Wakayama, Hiroshi Takano

Proceedings Volume 6762, 67620B (2007) https://doi.org/10.1117/12.733048

KEYWORDS: Microelectromechanical systems, Mirrors, Scanners, 3D scanning, 3D metrology, Binary data, Phase shifts, Laser scanners, Fringe analysis, Manufacturing

Read Abstract +

Proceedings Article | 19 October 2006 Paper

Light-driven micromanipulator and its application for 3D fabrications

Yukitoshi Otani, Yuji Hirai, Yasuhiro Mizutani, Norihiro Umeda, Toru Yoshizawa

Proceedings Volume 6374, 63740N (2006) https://doi.org/10.1117/12.689277

KEYWORDS: Optical fibers, Photothermal effect, Actuators, Optical actuators, Particles, Glasses, Finite element methods, 3D applications, Magnetism, 3D metrology

Read Abstract +

Proceedings Article | 12 October 2006 Paper

Inner profile measurement of pipes and holes using a ring beam device

Toru Yoshizawa, Masayuki Yamamoto, Toshitaka Wakayama

Proceedings Volume 6382, 63820D (2006) https://doi.org/10.1117/12.689317

KEYWORDS: Mirrors, Inspection, CCD cameras, Cameras, Prisms, Optical fabrication equipment, Polishing, Optical testing, Charge-coupled devices, Liquids

Read Abstract +

Proceedings Article | 12 October 2006 Paper

White light displacement sensor by spectro-polarization modulator

Yukitoshi Otani, Toshitaka Wakayama, Dmitry Orlov, Norihiro Umeda, Toru Yoshizawa

Proceedings Volume 6382, 638205 (2006) https://doi.org/10.1117/12.689279

KEYWORDS: Polarization, Modulators, Sensors, Spectroscopy, Optical sensors, Wave plates, Polarizers, Chromatic aberrations, Spectroscopes, Light sources

Read Abstract +

Proceedings Article | 7 March 2006 Paper

Three-dimensional profilometry using moire pattern projection

Toru Yoshizawa, Takayoshi Yamaguchi, Masayuki Yamamoto, Yukitoshi Otani

Proceedings Volume 4101, (2006) https://doi.org/10.1117/12.498432

KEYWORDS: Moire patterns, Binary data, Phase shifts, 3D metrology, Phase shifting, Liquid crystals, Prototyping, Fringe analysis, Phase measurement, Electronics

Read Abstract +

SPIE Journal Paper | 1 March 2006

Two-dimensional measurement of birefringence dispersion using spectroscopic polarized light

Toshitaka Wakayama, Hiroyuki Kowa, Yukitoshi Otani, Norihiro Umeda, Toru Yoshizawa

OE, Vol. 45, Issue 03, 033601, (March 2006) https://doi.org/10.1117/12.10.1117/1.2179787

KEYWORDS: Birefringence, Spectroscopy, Polarizers, Quartz, Modulation, Optical engineering, Wave plates, CCD cameras, Acousto-optics, Tunable filters

Read Abstract +

Proceedings Article | 7 November 2005 Paper

Three-dimensional shape measurement using focus method by liquid crystal grating and liquid varifocus lens

Yasuhiro Mizutani, Ryoichi Kuwano, Yukitoshi Otani, Norihiro Umeda, Toru Yoshizawa

Proceedings Volume 6000, 60000J (2005) https://doi.org/10.1117/12.633147

KEYWORDS: Liquids, Liquid lenses, Liquid crystals, Phase shifts, Phase shifting, 3D metrology, Inspection, Mirrors, Distance measurement, Sensors

Read Abstract +

Proceedings Article | 7 November 2005 Paper

Surface profile measurement by grating projection method with dual-projection optics

Masayuki Yamamoto, Toru Yoshizawa

Proceedings Volume 6000, 60000I (2005) https://doi.org/10.1117/12.630206

KEYWORDS: Calibration, Cameras, Liquid crystals, Image processing, 3D image processing, Projection systems, Phase measurement, Software, Reflectivity, Time metrology

Read Abstract +

Proceedings Article | 7 November 2005 Paper

Liquid crystal grating for profilmetry using structured light

Toru Yoshizawa, Hiroo Fujita

Proceedings Volume 6000, 60000H (2005) https://doi.org/10.1117/12.631482

KEYWORDS: Liquid crystals, Phase shifting, Transmittance, Projection systems, 3D metrology, Modulation, Binary data, Time metrology, Glasses, Structured light

Read Abstract +

Proceedings Article | 19 August 2005 Paper

Simultaneous measurement of a profile shape and deformation of an object by processing projected pattern and texture pattern

Toru Yoshizawa, Masayuki Yamamoto, Takahiro Ikeda

Proceedings Volume 5880, 588003 (2005) https://doi.org/10.1117/12.616199

KEYWORDS: Medical research, Fringe analysis, Speckle pattern, Mouth, Teeth, Mechanical engineering, Life sciences, Skin, CCD cameras, Image processing

Read Abstract +

SPIE Journal Paper | 1 January 2005

Optimizing design of high-resolution optical encoder using a point-source light-emitting diode with slits

Yuji Matsuzoe, Kazuhiro Koizumi, Tetsuya Saitoh, Toru Yoshizawa

OE, Vol. 44, Issue 01, 013609, (January 2005) https://doi.org/10.1117/12.10.1117/1.1829093

KEYWORDS: Computer programming, Light emitting diodes, Diffraction gratings, Light sources, Photodetectors, Optical design, Optical encoders, Light, Temperature metrology, Diffraction

Read Abstract +

Proceedings Article | 25 October 2004 Paper

Two-dimensional actuator using temperature-sensitive ferrite driven by light beam

Yukitoshi Otani, Yasuhiro Mizutani, Norihiro Umeda, Toru Yoshizawa

Proceedings Volume 5602, (2004) https://doi.org/10.1117/12.575373

KEYWORDS: Actuators, Optical actuators, Magnetism, Laser optics, Photothermal effect, Semiconductor lasers, Opto mechatronics, Light sources and illumination, Temperature metrology, Optical simulations

Read Abstract +

Proceedings Article | 23 October 2003 Paper

Three-dimensional imaging using liquid crystal grating projection

Toru Yoshizawa, Hiroo Fujita, Yukitoshi Otani, Masayuki Yamamoto

Proceedings Volume 5202, (2003) https://doi.org/10.1117/12.505287

KEYWORDS: Liquid crystals, Phase shifting, 3D image processing, Modulation, Transmittance, Projection systems, 3D metrology, Binary data, CCD cameras, Eye

Read Abstract +

Proceedings Article | 30 September 2003 Paper

Micromanipulator by photothermal effect

Yukitoshi Otani, Yasuto Matsuba, Shigeya Chimura, Norihiro Umeda, Toru Yoshizawa

Proceedings Volume 5264, (2003) https://doi.org/10.1117/12.515023

KEYWORDS: Optical fibers, Photothermal effect, Optical actuators, Microlens, Actuators, Magnetism, Photography, Opto mechatronics, Quartz, Glasses

Read Abstract +

SPIE Journal Paper | 1 July 2003

Research on solidification of resin in stereolithography

Shigeru Nagamori, Toru Yoshizawa

OE, Vol. 42, Issue 07, (July 2003) https://doi.org/10.1117/12.10.1117/1.1579704

KEYWORDS: Solids, Manufacturing, Stereolithography, Signal attenuation, 3D modeling, Laser scanners, Data modeling, Glasses, Optical engineering, Laser irradiation

Proceedings Article | 29 April 2003 Paper

Research on shape of solidified resin in stereo-lithography

Shigeru Nagamori, Toru Yoshizawa

Proceedings Volume 5058, (2003) https://doi.org/10.1117/12.509843

Read Abstract +

Proceedings Article | 29 April 2003 Paper

Three-dimensional profilometry using liquid crystal grating

Hiroo Fujita, Ken Yamatan, Masayuki Yamamoto, Yukitoshi Otani, Akira Suguro, Shigeru Morokawa, Toru Yoshizawa

Proceedings Volume 5058, (2003) https://doi.org/10.1117/12.509410

Read Abstract +

SPIE Journal Paper | 1 January 2003

High-performance absolute rotary encoder using multitrack and M-code

Yuji Matsuzoe, Nobuhiko Tsuji, Tomoharu Nakayama, Koetsu Fujita, Toru Yoshizawa

OE, Vol. 42, Issue 01, (January 2003) https://doi.org/10.1117/12.10.1117/1.1523943

KEYWORDS: Computer programming, Photodetectors, Signal detection, Distortion, Optical encoders, Binary data, Light emitting diodes, Optical engineering, Transistors, Sensors