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2. Volumetric Light-field Encryption at the Microscopic Scale

Author

Li, Haoyu, Guo, Changliang, Muniraj, Inbarasan, Schroeder, Bryce C., Sheridan, John T., and Jia, Shu

Subjects
Computer Science - Cryptography and Security, Computer Science - Computer Vision and Pattern Recognition, Physics - Biological Physics, Physics - Optics
Abstract

We report a light-field based method that allows the optical encryption of three-dimensional (3D) volumetric information at the microscopic scale in a single 2D light-field image. The system consists of a microlens array and an array of random phase/amplitude masks. The method utilizes a wave optics model to account for the dominant diffraction effect at this new scale, and the system point-spread function (PSF) serves as the key for encryption and decryption. We successfully developed and demonstrated a deconvolution algorithm to retrieve spatially multiplexed discrete and continuous volumetric data from 2D light-field images. Showing that the method is practical for data transmission and storage, we obtained a faithful reconstruction of the 3D volumetric information from a digital copy of the encrypted light-field image. The method represents a new level of optical encryption, paving the way for broad industrial and biomedical applications in processing and securing 3D data at the microscopic scale.

Published
2016

4. Fast 2D Subpixel Displacement Estimation.

Author

Wan, Min, Healy, John J., and Sheridan, John T.

Subjects
DISPLACEMENT (Mechanics), CALIBRATION
Abstract

Fast and simple methods for motion estimation with subpixel accuracy are of interest in a variety of applications. In this paper, we extend a recently proposed method for quantifying 1D displacements with subpixel accuracy, referred to as the subtraction method (SM) to 2D motion. Simulation and experimental results are presented. The results indicate that any general motion in 2D involving combinations of in-plane motions in x and y can be determined using SM after a 1D calibration. The errors between the actual motion and estimated are examined. [ABSTRACT FROM AUTHOR]

Published
2024
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6. Deterministic Phase Retrieval Using the LCT

Author

Gopinathan, Unnikrishnan, Healy, John J., Kelly, Damien P., Sheridan, John T., Rhodes, William T., Editor-in-chief, Adibi, Ali, Series editor, Hänsch, Theodor W., Series editor, Krausz, Ferenc, Series editor, Masters, Barry R., Series editor, Venghaus, Herbert, Series editor, Weber, Horst, Series editor, Weinfurter, Harald, Series editor, Midorikawa, Katsumi, Series editor, Healy, John J., editor, Alper Kutay, M., editor, Ozaktas, Haldun M., editor, and Sheridan, John T., editor

Published
2016
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7. Analyzing Digital Holographic Systems with the LCT

Author

Kelly, Damien P., Sheridan, John T., Rhodes, William T., Editor-in-chief, Adibi, Ali, Series editor, Hänsch, Theodor W., Series editor, Krausz, Ferenc, Series editor, Masters, Barry R., Series editor, Venghaus, Herbert, Series editor, Weber, Horst, Series editor, Weinfurter, Harald, Series editor, Midorikawa, Katsumi, Series editor, Healy, John J., editor, Alper Kutay, M., editor, Ozaktas, Haldun M., editor, and Sheridan, John T., editor

Published
2016
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14. Comparative Analysis of Discrete Subtraction and Cross-Correlation for Subpixel Object Tracking [Software]

Author

Universidad de Alicante. Departamento de Ingeniería Civil, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Ferrer, Belén, Tomás López, María Baralida, Wan, Min, Sheridan, John T., Mas, David, Universidad de Alicante. Departamento de Ingeniería Civil, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Ferrer, Belén, Tomás López, María Baralida, Wan, Min, Sheridan, John T., and Mas, David

Abstract

Many applications in physics and engineering require non-invasive, precise object tracking, which can be achieved with image processing methods at very good cost-efficiency ratios. The traditional method for measuring displacement with subpixel resolution involves cross-correlation between images and interpolation of the correlation peak. While this method enables target tracking with a resolution of thousandths of a pixel, it is computationally intensive and susceptible to peak-locking errors. Recently, a new method based on discrete subtraction between images has been presented as an alternative to cross-correlation to improve computational efficiency, which also results in being free of peak-locking errors. This manuscript presents an experimental evaluation of the performance of the discrete subtraction method (DSM) and compares it with the cross-correlation method in terms of subpixel accuracy and deviation errors. Four different targets were used with apparent displacements as small as 0.002 px, which approaches the theoretical digital resolution limit. The results show that the discrete subtraction method is more sensitive to noise but does not suffer from peak-locking error, thus being a reliable alternative to the correlation method, mainly for calibration processes.

Published
2023

15. Comparative Analysis of Discrete Subtraction and Cross-Correlation for Subpixel Object Tracking

Author

Universidad de Alicante. Departamento de Ingeniería Civil, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Ferrer, Belén, Tomás López, María Baralida, Wan, Min, Sheridan, John T., Mas, David, Universidad de Alicante. Departamento de Ingeniería Civil, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Ferrer, Belén, Tomás López, María Baralida, Wan, Min, Sheridan, John T., and Mas, David

Abstract

Many applications in physics and engineering require non-invasive, precise object tracking, which can be achieved with image processing methods at very good cost-efficiency ratios. The traditional method for measuring displacement with subpixel resolution involves cross-correlation between images and interpolation of the correlation peak. While this method enables target tracking with a resolution of thousandths of a pixel, it is computationally intensive and susceptible to peak-locking errors. Recently, a new method based on discrete subtraction between images has been presented as an alternative to cross-correlation to improve computational efficiency, which also results in being free of peak-locking errors. This manuscript presents an experimental evaluation of the performance of the discrete subtraction method (DSM) and compares it with the cross-correlation method in terms of subpixel accuracy and deviation errors. Four different targets were used with apparent displacements as small as 0.002 px, which approaches the theoretical digital resolution limit. The results show that the discrete subtraction method is more sensitive to noise but does not suffer from peak-locking error, thus being a reliable alternative to the correlation method, mainly for calibration processes.

Published
2023

33. Celebrating holography anniversaries: a historical perspective

Author

Beléndez, Augusto, Sheridan, John T., Pascual, Inmaculada, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering. College of Arquitecture and Engineering, Holografía y Procesado Óptico, and GITE - Física, Óptica y Telecomunicaciones

Subjects
Física Aplicada, Gabor, Holography, Leith, Denisyuk, Hologram, Óptica
Abstract

The year 2022 marks the 75th anniversary of Dennis Gabor’s invention of the holographic method, what he called “microscopy by reconstructed wave-fronts”, as well as the 60th anniversary of the publication in 1962 of two seminal papers in the field of holography: the introduction of the reflection hologram by Yuri Denisyuk, and the description of the holographic process from the point of view of communication theory by Emmett Leith and Juris Upatnieks. Within the framework of these celebrations, a historical review of the origins of holography is presented with special emphasis on the contributions of Gabor, Denisyuk and Leith to the development of holography. This work was supported by the by “Generalitat Valenciana” of Spain (projects PROMETEO/2021/006 and IDIFEDER/2021/014, cofunded by European Union through the FEDER Programme) and by the “Ministerio de Ciencia e Innovación” of Spain (projects FIS2017-82919-R and PID2019-106601RB-I00).

Published
2022

34. Celebrating holography anniversaries: a historical perspective

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering. College of Arquitecture and Engineering, Beléndez, Augusto, Sheridan, John T., Pascual, Inmaculada, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering. College of Arquitecture and Engineering, Beléndez, Augusto, Sheridan, John T., and Pascual, Inmaculada

Abstract

The year 2022 marks the 75th anniversary of Dennis Gabor?s invention of the holographic method, what he called microscopy by reconstructed wave-fronts, as well as the 60th anniversary of the publication in 1962 of two seminal papers in the field of holography: the introduction of the reflection hologram by Yuri Denisyuk, and the description of the holographic process from the point of view of communication theory by Emmett Leith and Juris Upatnieks. Within the framework of these celebrations, a historical review of the origins of holography is presented with special emphasis on the contributions of Gabor, Denisyuk and Leith to the development of holography.

Published
2022

35. Creating holography: 75th anniversary of Gabor’s invention

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering, Beléndez, Augusto, Sheridan, John T., Pascual, Inmaculada, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering, Beléndez, Augusto, Sheridan, John T., and Pascual, Inmaculada

Abstract

The year 2022 marks the 75th anniversary of Dennis Gabor’s invention of the holographic method and for which he received the Nobel Prize in Physics in 1971. The year 2022 also marks the sixtieth anniversary of the publication in 1962 of two seminal papers in the field of holography. In one of them Yuri Denisyuk introduces the reflection hologram and in the other paper Emmeth Leith and Juris Upatnieks describe the holographic process from a communication- theory viewpoint. In this paper, we carry out a brief description of the different “origins” of holography, making special mention to the way Gabor, Denisyuk y Leith established the basis, which made possible the spectacular development of holography from the invention of the laser at the beginning of the decade of 1960.

Published
2022

36. Holography: 50th anniversary of Dennis Gabor’s Nobel Prize: Part I. A historical perspective

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering, Beléndez, Augusto, Sheridan, John T., Pascual, Inmaculada, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering, Beléndez, Augusto, Sheridan, John T., and Pascual, Inmaculada

Abstract

A historical review of the origins of holography is presented. Special emphasis is placed on the contributions of Gabor, Denisyuk and Leith to the development of holography, to motivate and inspire students and young researchers.

Published
2022

37. Holography: 50th anniversary of Dennis Gabor’s Nobel Prize: Part II. An engineering perspective

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering, Sheridan, John T., Beléndez, Augusto, Pascual, Inmaculada, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering, Sheridan, John T., Beléndez, Augusto, and Pascual, Inmaculada

Abstract

The holographic principle, discovered by Gabor, and realized by Leith & Upatnieks and Denisyuk is discussed. The intrinsic value of this idea and its continuing ability to motivate and inspire engineers and applied physicists is reviewed.

Published
2022

42. Creating holography: 75th anniversary of Gabor’s invention

Author

Beléndez, Augusto, Sheridan, John T., Pascual, Inmaculada, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering, Holografía y Procesado Óptico, and GITE - Física, Óptica y Telecomunicaciones

Subjects
Física Aplicada, Gabor, Holography, Leith, Denisyuk, Hologram, Historia de la Ciencia, Nobel Prize, Óptica
Abstract

The year 2022 marks the 75th anniversary of Dennis Gabor’s invention of the holographic method and for which he received the Nobel Prize in Physics in 1971. The year 2022 also marks the sixtieth anniversary of the publication in 1962 of two seminal papers in the field of holography. In one of them Yuri Denisyuk introduces the reflection hologram and in the other paper Emmeth Leith and Juris Upatnieks describe the holographic process from a communication- theory viewpoint. In this paper, we carry out a brief description of the different “origins” of holography, making special mention to the way Gabor, Denisyuk y Leith established the basis, which made possible the spectacular development of holography from the invention of the laser at the beginning of the decade of 1960. This work was supported by the “Generalitat Valenciana” of Spain (projects PROMETEO/2021/006; IDIFEDER/2021/014, potential FEDER funding) and by the “Ministerio de Ciencia e Innovación” of Spain (project PID2019-106601RB-I00).

Published
2022

50. Holography: 50th Anniversary of Dennis Gabor’s Nobel Prize. Part I. A historical perspective

Author

Beléndez, Augusto, Sheridan, John T., Pascual, Inmaculada, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering, and Holografía y Procesado Óptico

Subjects
Emmett Leith, Dennis Gabor, Yuri Denisyuk, Física Aplicada, Holography, Historical perspective, Óptica
Abstract

A historical review of the origins of holography is presented. Special emphasis is placed on the contributions of Gabor, Denisyuk and Leith to the development of holography, to motivate and inspire students and young researchers. This work was supported by the by “Generalitat Valenciana” of Spain (projects PROMETEO/2021/006 and IDIFEDER/2021/014, cofunded by European Union through the FEDER Programme), by the “Ministerio de Ciencia e Innovación” of Spain (projects FIS2017-82919-R and PID2019-106601RB-I00), and by the Science Foundation Ireland, The Irish Research Council for Science Engineering and Technology, Enterprise Ireland, and the European Commission.

Published
2021

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