Dr. Jonathan D. Kofman Profile

Dr. Jonathan D. Kofman

Professor at Univ of Waterloo

SPIE Involvement:

Conference Program Committee | Author

Publications (21)

SPIE Journal Paper | 15 August 2014

Modified sinusoidal fringe-pattern projection for variable illuminance in phase-shifting three-dimensional surface-shape metrology

Christopher Waddington, Jonathan Kofman

OE, Vol. 53, Issue 08, 084109, (August 2014) https://doi.org/10.1117/12.10.1117/1.OE.53.8.084109

KEYWORDS: Cameras, Signal to noise ratio, Modulation, Fringe analysis, Phase shifts, Projection systems, Calibration, Reflectivity, Imaging systems, Light sources and illumination

Read Abstract +

Proceedings Article | 17 November 2008 Paper

Neural-network calibration of a multiple-line laser-camera range sensor for 3D surface-geometry measurement

Chris Yu-Liang Liu, Jonathan Kofman

Proceedings Volume 7266, 72661J (2008) https://doi.org/10.1117/12.817411

KEYWORDS: Calibration, 3D metrology, Sensors, Cameras, Neural networks, 3D image processing, 3D modeling, Projection systems, Artificial neural networks, Laser marking

Read Abstract +

Proceedings Article | 8 October 2007 Paper

Multiple-line full-field laser-camera range sensor

Jonathan Kofman, Jeffrey Wu, Kiatchai Borribanbunpotkat

Proceedings Volume 6718, 67180A (2007) https://doi.org/10.1117/12.754551

KEYWORDS: Calibration, Cameras, 3D metrology, Sensors, Laser marking, 3D image processing, Projection systems, Diffraction, Image sensors, 3D acquisition

Read Abstract +

SPIE Journal Paper | 1 August 2007

Two-step triangular-pattern phase-shifting method for three-dimensional object-shape measurement

Peirong Jia, Jonathan Kofman, Chad English

OE, Vol. 46, Issue 08, 083201, (August 2007) https://doi.org/10.1117/12.10.1117/1.2768616

KEYWORDS: Phase shifts, Projection systems, Image processing, 3D metrology, Fringe analysis, 3D modeling, Calibration, 3D image processing, Cameras, Optical engineering

Read Abstract +

SPIE Journal Paper | 1 April 2007

Comparison of linear and nonlinear calibration methods for phase-measuring profilometry

Peirong Jia, Jonathan Kofman, Chad English

OE, Vol. 46, Issue 04, 043601, (April 2007) https://doi.org/10.1117/12.10.1117/1.2721025

KEYWORDS: Calibration, Projection systems, 3D modeling, Nonlinear optics, 3D metrology, Cameras, Phase measurement, 3D image processing, Phase shifts, Optical engineering

Read Abstract +

Proceedings Article | 20 October 2006 Paper

Triangular phase-shifting algorithms for surface measurement

Peirong Jia, Jonathan Kofman, Chad English

Proceedings Volume 6375, 63750C (2006) https://doi.org/10.1117/12.690734

KEYWORDS: Phase shifts, Algorithm development, Fringe analysis, Phase shifting, Reconstruction algorithms, 3D metrology, 3D modeling, Image processing, 3D image reconstruction, 3D image processing

Read Abstract +

Proceedings Article | 18 October 2006 Paper

Repeated phase-offset measurement for error compensation in two-step triangular phase-shifting profilometry

Peirong Jia, Jonathan Kofman, Chad English

Proceedings Volume 6375, 63750D (2006) https://doi.org/10.1117/12.690735

KEYWORDS: Phase shifts, Projection systems, Phase measurement, 3D metrology, Cameras, Error analysis, Fringe analysis, 3D modeling, CCD cameras, Calibration

Read Abstract +

Proceedings Article | 6 December 2005 Paper

Comparison of linear and non-linear calibration methods for phase-shifting surface-geometry measurement

Peirong Jia, Jonathan Kofman, Chad English, Adam Deslauriers

Proceedings Volume 6051, 60510G (2005) https://doi.org/10.1117/12.649016

KEYWORDS: Calibration, Phase shifts, 3D modeling, 3D metrology, Phase measurement, Fringe analysis, Cameras, 3D image processing, Projection systems, Image processing

Read Abstract +

Proceedings Article | 6 December 2005 Paper

Two-step triangular phase-shifting method for 3-D object-shape measurement

Peirong Jia, Jonathan Kofman, Chad English, Adam Deslauriers

Proceedings Volume 6049, 60490G (2005) https://doi.org/10.1117/12.649009

KEYWORDS: Phase shifts, 3D metrology, 3D modeling, Projection systems, Fringe analysis, Phase shifting, Cameras, 3D image processing, Digital Light Processing, Image processing

Read Abstract +

Proceedings Article | 25 October 2004 Paper

Neural-network approach to determine operator hand orientation for teleoperated control of a robot manipulator

Cedric Cocaud, Jonathan Kofman, Amor Jnifene

Proceedings Volume 5602, (2004) https://doi.org/10.1117/12.580349

KEYWORDS: Neural networks, Sensors, Image segmentation, Neurons, Cameras, Image filtering, Visualization, 3D image processing, Image processing, 3D modeling

Read Abstract +

Proceedings Article | 25 October 2004 Paper

Lens distortion calibration by explicit straight-line to distorted-line geometric mapping

Xianghai Wu, Jonathan Kofman

Proceedings Volume 5603, (2004) https://doi.org/10.1117/12.580341

KEYWORDS: Distortion, Calibration, Cameras, Algorithm development, Optimization (mathematics), Sensors, Intelligence systems, Machine vision, 3D modeling, Human-machine interfaces

Read Abstract +

Proceedings Article | 30 September 2003 Paper

Teleoperation of a robot manipulator from 3D human hand-arm motion

Jonathan Kofman, Siddharth Verma, Xianghai Wu, Timothy Luu

Proceedings Volume 5264, (2003) https://doi.org/10.1117/12.515683

KEYWORDS: Cameras, Control systems, Human-machine interfaces, Visualization, Robotic systems, Computing systems, Robot vision, Imaging systems, Optical tracking, Chromium

Read Abstract +

Proceedings Article | 30 September 2003 Paper

Real-time estimation of 3D human arm motion from markerless images for human-machine interaction

Siddharth Verma, Jonathan Kofman

Proceedings Volume 5264, (2003) https://doi.org/10.1117/12.515704

KEYWORDS: Cameras, 3D image processing, Image processing, Image segmentation, Human-machine interfaces, Calibration, Motion estimation, Edge detection, Computing systems, Sensors

Read Abstract +

SPIE Journal Paper | 1 May 2003

Continuous unconstrained range sensing of free-form surfaces without sensor-head pose measurement

Jonathan Kofman, George Knopf

OE, Vol. 42, Issue 05, (May 2003) https://doi.org/10.1117/12.10.1117/1.1563235

KEYWORDS: Sensors, Head, Image registration, Cameras, Data acquisition, Optical engineering, Motion measurement, Position sensors, Image storage, Error analysis

Proceedings Article | 18 October 2002 Paper

Shape measurement using an experimental untracked range sensor

George Knopf, Archana Sangole, Jonathan Kofman

Proceedings Volume 4902, (2002) https://doi.org/10.1117/12.467719

KEYWORDS: Sensors, Head, Image registration, Calibration, Cameras, CCD cameras, Beam splitters, Data acquisition, CCD image sensors, Prototyping

Read Abstract +

SPIE Journal Paper | 1 April 2002

Surface reconstruction using a neural network mapping of range-sensor images to object space

George Knopf, Jonathan Kofman

JEI, Vol. 11, Issue 02, (April 2002) https://doi.org/10.1117/12.10.1117/1.1453411

KEYWORDS: Calibration, Neural networks, Neurons, Sensors, Associative arrays, Geometrical optics, Distortion, Reconstruction algorithms, Computer aided design, Reverse engineering

Proceedings Article | 12 February 2001 Paper

Surface-geometry measurement using an untracked range-sensor head

Jonathan Kofman, George Knopf

Proceedings Volume 4190, (2001) https://doi.org/10.1117/12.417216

KEYWORDS: Sensors, Head, Image registration, Data acquisition, Cameras, Position sensors, Motion measurement, Magnetic sensors, 3D acquisition, Data storage

Read Abstract +

Proceedings Article | 24 November 1999 Paper

Multisensor fusion for geometric-part inspection

George Knopf, Jonathan Kofman

Proceedings Volume 3832, (1999) https://doi.org/10.1117/12.371188

KEYWORDS: Cameras, Inspection, Feature extraction, Data fusion, Sensors, Image processing, Tolerancing, Image fusion, Image registration, Imaging systems

Read Abstract +

Proceedings Article | 26 August 1999 Paper

Point correspondences between successive range views using localized spin images

Jonathan Kofman, George Knopf

Proceedings Volume 3837, (1999) https://doi.org/10.1117/12.360308

KEYWORDS: Image registration, Image processing, Object recognition, Machine vision, Computer vision technology, Range image registration, Iterative methods, Information technology, Error analysis, Mechanical engineering

Read Abstract +

Proceedings Article | 2 October 1998 Paper

Registration and integration of narrow and spatiotemporally dense range views

Jonathan Kofman, George Knopf

Proceedings Volume 3454, (1998) https://doi.org/10.1117/12.323279

KEYWORDS: Sensors, Curium, Image registration, Algorithm development, Data acquisition, Motion measurement, Computer simulations, Range image registration, Distance measurement, Laser range finders

Read Abstract +

Proceedings Article | 29 October 1996 Paper

Neural network mapping of image-to-object coordinates for 3D shape reconstruction

George Knopf, Jonathan Kofman

Proceedings Volume 2904, (1996) https://doi.org/10.1117/12.256268

KEYWORDS: Neurons, Neural networks, 3D image processing, Calibration, 3D image reconstruction, 3D metrology, CCD cameras, Light sources and illumination, Cameras, Associative arrays

Read Abstract +