Dr. Joseph van der Gracht Profile

Dr. Joseph van der Gracht

Research Scientist at HoloSpex Inc

SPIE Involvement:

Conference Program Committee | Author

Publications (20)

PROCEEDINGS ARTICLE | April 30, 2009

A practical enhanced-resolution integrated optical-digital imaging camera (PERIODIC)

Proc. SPIE. 7348, Modeling and Simulation for Military Operations IV

KEYWORDS: Optical components, Super resolution, Imaging systems, Cameras, Image processing, Image resolution, CCD cameras, High dynamic range imaging, Charge-coupled devices, Imaging arrays

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PROCEEDINGS ARTICLE | September 3, 2008

Pupil phase encoding for multi-aperture imaging

Proc. SPIE. 7074, Advanced Signal Processing Algorithms, Architectures, and Implementations XVIII

KEYWORDS: Point spread functions, Super resolution, Imaging systems, Cameras, Sensors, Image resolution, Computer programming, Digital imaging, Spatial resolution, Inverse optics

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PROCEEDINGS ARTICLE | April 25, 2008

Extended depth of field imaging at 94 GHz

Proc. SPIE. 6948, Passive Millimeter-Wave Imaging Technology XI

KEYWORDS: Optical components, Optical transfer functions, Point spread functions, Computational imaging, Imaging systems, Image processing, Computing systems, Signal processing, Modulation transfer functions, Focus stacking

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PROCEEDINGS ARTICLE | August 25, 2006

High-resolution iris image reconstruction from low-resolution imagery

Proc. SPIE. 6313, Advanced Signal Processing Algorithms, Architectures, and Implementations XVI

KEYWORDS: Point spread functions, Imaging systems, Cameras, Sensors, Image resolution, Iris recognition, Image registration, Image quality, Charge-coupled devices, Prototyping

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PROCEEDINGS ARTICLE | March 28, 2005

Extended depth-of-field iris recognition system for a workstation environment

Proc. SPIE. 5779, Biometric Technology for Human Identification II

KEYWORDS: Signal to noise ratio, Biometrics, Modulation, Imaging systems, Spatial frequencies, Sensors, Image processing, Wavefronts, Iris recognition, Modulation transfer functions

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PROCEEDINGS ARTICLE | October 26, 2004

Pupil-phase optimization for extended-focus, aberration-corrected imaging systems

Proc. SPIE. 5559, Advanced Signal Processing Algorithms, Architectures, and Implementations XIV

KEYWORDS: Signal to noise ratio, Monochromatic aberrations, Point spread functions, Imaging systems, Image restoration, Iris recognition, Image quality, Image filtering, Modulation transfer functions, Personal protective equipment

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PROCEEDINGS ARTICLE | October 26, 2004

Computational imaging systems for iris recognition

Proc. SPIE. 5559, Advanced Signal Processing Algorithms, Architectures, and Implementations XIV

KEYWORDS: Computational imaging, Detection and tracking algorithms, Imaging systems, Cameras, Image processing, Image restoration, Computing systems, Iris recognition, Computer programming, Feature extraction

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PROCEEDINGS ARTICLE | July 15, 2004

Iris recognition with enhanced depth-of-field image acquistion

Proc. SPIE. 5438, Visual Information Processing XIII

KEYWORDS: Signal to noise ratio, Detection and tracking algorithms, Imaging systems, Cameras, Wavelets, Image restoration, Iris recognition, Image filtering, Aspheric lenses, Modulation transfer functions

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PROCEEDINGS ARTICLE | December 24, 2003

Integrated optical-digital approaches for enhancing image restoration and focus invariance

Proc. SPIE. 5205, Advanced Signal Processing Algorithms, Architectures, and Implementations XIII

KEYWORDS: Optical transfer functions, Point spread functions, Optical design, Imaging systems, Image restoration, Fourier transforms, Interference (communication), Wavefronts, Integrated optics, Modulation transfer functions

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PROCEEDINGS ARTICLE | October 6, 2003

Visual experimentation

Proc. SPIE. 9663, Eighth International Topical Meeting on Education and Training in Optics and Photonics

KEYWORDS: Optical filters, Light sources, Visualization, Spectroscopy, Reflectivity, Computer generated holography, Photonics, Visual optics, Electrochemical etching, Diffraction gratings

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PROCEEDINGS ARTICLE | August 8, 2003

Engineering the pupil phase to improve image quality

Proc. SPIE. 5108, Visual Information Processing XII

KEYWORDS: Signal to noise ratio, Monochromatic aberrations, Point spread functions, Imaging systems, Image restoration, Computer programming, Computer simulations, Image quality, Modulation transfer functions, Personal protective equipment

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PROCEEDINGS ARTICLE | July 30, 2002

Design of a diffractive anti-aliasing filter using information density

Proc. SPIE. 4736, Visual Information Processing XI

KEYWORDS: Signal to noise ratio, Optical transfer functions, Optical filters, Optical design, Imaging systems, Spatial frequencies, Sensors, Signal attenuation, Visual information processing, Phase only filters

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PROCEEDINGS ARTICLE | July 30, 2002

Experimental investigation of aliasing in the assessment of sampled images

Proc. SPIE. 4736, Visual Information Processing XI

KEYWORDS: Signal to noise ratio, Optical filters, Imaging systems, Spatial frequencies, Cameras, Sensors, Error analysis, Image registration, Image filtering, Electronic filtering

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PROCEEDINGS ARTICLE | August 28, 2001

Information-optimized extended depth-of-field imaging systems

Proc. SPIE. 4388, Visual Information Processing X

KEYWORDS: Signal to noise ratio, Imaging systems, Spatial frequencies, Sensors, Image restoration, Wavefronts, Image quality, Modulation transfer functions, Information theory, Image quality standards

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PROCEEDINGS ARTICLE | June 29, 2000

Information theoretic analysis of birefringent antialiasing blur filters in the presence of aberrations

Proc. SPIE. 4041, Visual Information Processing IX

KEYWORDS: Monochromatic aberrations, Point spread functions, Optical filters, Imaging systems, Spatial frequencies, Sensors, Detector arrays, Image filtering, Modulation transfer functions, Information theory

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PROCEEDINGS ARTICLE | August 11, 1995

Aspheric optical elements for extended depth-of-field imaging

Proc. SPIE. 2537, Novel Optical Systems Design and Optimization

KEYWORDS: Optical components, Diffraction, Optical transfer functions, Point spread functions, Imaging systems, Spatial frequencies, Sensors, Digital filtering, Digital imaging, Modulation transfer functions

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PROCEEDINGS ARTICLE | March 1, 1994

Role of coherence in optical pattern recognition

Proc. SPIE. 2237, Optical Pattern Recognition V

KEYWORDS: Signal to noise ratio, Point spread functions, Optical signal processing, Modulation, Image processing, Phase shift keying, Spatial light modulators, Optical pattern recognition, Optical correlators, Phase only filters

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PROCEEDINGS ARTICLE | October 25, 1993

Diffractive filter design for SLMs in pattern recognition systems

Proc. SPIE. 1959, Optical Pattern Recognition IV

KEYWORDS: Optical filters, Diffractive optical elements, Modulation, Pattern recognition, Fourier transforms, Spatial light modulators, Quantization, Image filtering, Electronic filtering, Optical pattern recognition

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PROCEEDINGS ARTICLE | March 2, 1993

Diffractive filter design for SLMs in optical processing and pattern recognition systems

Proc. SPIE. 1732, Holographics International '92

KEYWORDS: Optical filters, Optical design, Holography, Optical signal processing, Diffractive optical elements, Modulation, Pattern recognition, Fourier transforms, Spatial light modulators, Optical pattern recognition

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PROCEEDINGS ARTICLE | November 16, 1992

Photonics for aerospace sensors

Proc. SPIE. 10269, Optical Technologies for Aerospace Sensing: A Critical Review

KEYWORDS: Optical components, Optical signal processing, Aerospace engineering, Fiber optics, Sensors, Signal processing, Photonics, Optical communications, Fiber optic communications, Data communications

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