Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
2.3
2.4
Journals
Photonics
Special Issues
Research in Computational Optics
share announcement

Research in Computational Optics

A special issue of Photonics (ISSN 2304-6732).

Deadline for manuscript submissions: closed (31 December 2023) | Viewed by 10545

Special Issue Editors

Prof. Dr. Vijayakumar Anand

E-Mail Website
Guest Editor
Institute of Physics, University of Tartu, Ülikooli 18, 50090 Tartu, Estonia
Interests: synchrotron infrared beamline; synchrotron THz beamline; incoherent imaging; computational optics; hyperspectral imaging; diffractive optics; IR and THz multidimensional imaging; micro/nanofabrication
Special Issues, Collections and Topics in MDPI journals
Dr. Ravi Kumar

E-Mail Website
Guest Editor
Assistant Professor, Department of Physics, SRM University-AP Amaravati, Andhra Pradesh 522502, India
Interests: cryptography; optical security; imaging; holography
Dr. Vinoth Balasubramani

E-Mail Website
Guest Editor
Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
Interests: optical architect; information optics; display optics; coherent and incoherent imaging and analysis; optical beam manipulations, quantitative microscopy and tomography, holographic optical elements; biomedical optics; optical sensors; aberration correction; adaptive optics
Dr. Andra Naresh Kumar Reddy

E-Mail Website
Guest Editor
Laboratory of Nonlinear Optics, University of Latvia, Jelgavas 3, Riga, LV-1004, Latvia
Interests: laser physics; laser beam shaping; micro-optics; light-matter interaction; structured lights; non-diffracting beams; phase-locked lasers; diffractive optical elements; metasurfaces and metalenses; vortex beams; computer-generated holography; optical imaging; point spread function; apodization
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

MDPI’s journal Photonics welcomes submissions for the Special Issue, “Computational Optics”, which has formed the backbone of many rapidly evolving optical technologies in the 21st century. Computational optical methods have occupied a significant space in optics research, contributing to the design of optical components, simulation of optical fields, reconstruction of images, noise reduction, aberration correction, cryptography, and tomography. In some cases, the introduction of computational methods resulted in hybrid research areas such as computational imaging, which has transformed the field of imaging. This Special Issue aims to focus on the latest developments in computational techniques that can impact an area of optics. There have been many Special Issues on topics such as holography, cryptography, optical trapping, computational imaging, etc., but no Special Issue is available on computational methods for imaging.

This Special Issue is focused on the recent developments on computational optics and related technologies. The topics of interest include (but are not limited to) the following:

  • Holography;
  • Computational imaging;
  • Diffractive optics;
  • Microscopy;
  • Quantitative phase imaging;
  • Tomography;
  • Structured light;
  • Optical security;
  • Cryptography;
  • Laser beam shaping;
  • Metalenses;
  • Micro/nanofabrication;
  • Femtosecond fabrication;
  • OAM beams;
  • Nondiffracting beams with space-time correlations;
  • Nonlinear optics and related systems;
  • Optoelectronic materials and devices.

We cordially invite you to contribute to this Special Issue by submitting your manuscript containing new, high-quality, and unpublished material before December 31st, 2023. All types of submissions such as reviews, tutorials, and original research articles will be published. All manuscripts will be subject to a standard review procedure and judged based on their degree of novelty, relevance, and quality of presentation. The rapid review and processing of submissions is supported by an online submission process with a record review time of an average of 13.2 days. Manuscripts will be published immediately within 2.6 days after acceptance. The editors will organize a roadmap and tutorial collection on topics of interest. Please contact the editors if you are interested in such contributions.

Prof. Dr. Vijayakumar Anand
Dr. Ravi Kumar
Dr. Vinoth Balasubramani
Dr. Andra Naresh Kumar Reddy
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Photonics is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Published Papers (8 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

Jump to: Review

25 pages, 8379 KiB  
Article
An Intriguing Interpretation of 1D and 2D Non-Diffracting Modes in Cosine Profile
by Allam Srinivasa Rao
Photonics 2023, 10(12), 1358; https://doi.org/10.3390/photonics10121358 - 08 Dec 2023
Viewed by 665
Abstract
We provide a simple analysis based on ray optics and Dirac notation for 1D (one-dimensional) and 2D (two-dimensional) non-diffracting modes in the cosine profile, which are often called Cosine beams. We explore various kinds of structured modes formed by the superposition of two [...] Read more.
We provide a simple analysis based on ray optics and Dirac notation for 1D (one-dimensional) and 2D (two-dimensional) non-diffracting modes in the cosine profile, which are often called Cosine beams. We explore various kinds of structured modes formed by the superposition of two 1D Cosine beams. We then went on to understand the properties of the Bessel beams in terms of Cosine beams. For the first time, we report on the generation of three-dimensional tunable needle structures based on the interference of 1D Cosine beams. These size-tunable optical needles can have multiple advantages in material processing. Also, we report, for the first time, on the Talbot effect in Cosine beams. Straightforward mathematical calculations are used to derive analytical expressions for Cosine beams. The present method of demonstrating Cosine beams may be utilized to understand other structured modes. The Dirac notation-based interference explanation used here can provide new researchers with an easy way to understand the wave nature of light in a fundamental aspect of interferometric experiments as well as in advanced-level experiments such as beam engineering technology, imaging, particle manipulation, light sheet microscopy, and light–matter interaction. We also provide an in-depth analysis of similarities among Cosine, Bessel, and Hermite–Gaussian beams. Full article
(This article belongs to the Special Issue Research in Computational Optics)
►▼ Show Figures

Figure 1

14 pages, 5661 KiB  
Article
Illustrations of Bessel Beams in s-Polarization, p-Polarization, Transverse Polarization, and Longitudinal Polarization
by A. Srinivasa Rao
Photonics 2023, 10(10), 1092; https://doi.org/10.3390/photonics10101092 - 29 Sep 2023
Cited by 1 | Viewed by 880
Abstract
The generation of Bessel beams (BBs) and their characterization in a wide range of the electromagnetic spectrum are well established. The unique properties of BBs, including their non-diffracting and self-healing nature, make them efficient for use in material science and engineering technology. Here, [...] Read more.
The generation of Bessel beams (BBs) and their characterization in a wide range of the electromagnetic spectrum are well established. The unique properties of BBs, including their non-diffracting and self-healing nature, make them efficient for use in material science and engineering technology. Here, I investigate the polarization components (s-polarization, p-polarization, transverse polarization, and longitudinal polarization) created in scalar BBs owing to their conical wave front. For emphasis, I provide a theoretical analysis to characterize potential experimental artifacts created in the four polarization components. Further, I provide a brief discussion on how to prevent these artifacts in scalar BBs. To my knowledge, for the first time, I can generate vector BBs in s-polarization and p-polarization via the superposition of two orthogonally polarized scalar BBs. This method of generation can provide the four well-known types of vector modes categorized in the V-point phase singularity vector modes. I suggest a suitable experimental configuration for realizing my theoretical results experimentally. The present analysis is very practical and beneficial for young researchers who seek to utilize BBs in light applications of modern science and technology. Full article
(This article belongs to the Special Issue Research in Computational Optics)
►▼ Show Figures

Figure 1

13 pages, 4817 KiB  
Article
Conditions for Minimizing the Computational Complexity of the RCWA Calculation of the Diffraction Efficiency of Sawtooth Two-Layer Double-Relief Microstructures
by Grigoriy I. Greisukh, Artem I. Antonov, Evgeniy G. Ezhov, Viktor A. Danilov and Boris A. Usievich
Photonics 2023, 10(7), 794; https://doi.org/10.3390/photonics10070794 - 10 Jul 2023
Cited by 1 | Viewed by 717
Abstract
In this study, novel recommendations are presented and substantiated for selecting the number of modes and optical thicknesses of flat lattice slabs that make up microreliefs, which minimize the computational complexity of the rigorous coupled-wave analysis calculation of the diffraction efficiency (DE) of [...] Read more.
In this study, novel recommendations are presented and substantiated for selecting the number of modes and optical thicknesses of flat lattice slabs that make up microreliefs, which minimize the computational complexity of the rigorous coupled-wave analysis calculation of the diffraction efficiency (DE) of a sawtooth two-layer two-relief microstructure, while maintaining the specified reliability of the calculation results. The computational complexity can be controlled by allowing one or another level of oscillation of the DE curves, depending on the angle of incidence of the radiation incident on the microstructure. In particular, the complexity of the thousands of DE calculations in the optimization process can be reduced by using the proposed methodology as well as increased computational complexity to verify the accuracy of the solution obtained as a result of the implemented optimization. Full article
(This article belongs to the Special Issue Research in Computational Optics)
►▼ Show Figures

Figure 1

8 pages, 2159 KiB  
Communication
Calcination-Enhanced Laser-Induced Damage Threshold of 3D Micro-Optics Made with Laser Multi-Photon Lithography
by Darius Gailevicius, Rokas Zvirblis, Karolis Galvanauskas, Gintare Bataviciute and Mangirdas Malinauskas
Photonics 2023, 10(5), 597; https://doi.org/10.3390/photonics10050597 - 21 May 2023
Cited by 3 | Viewed by 1393
Abstract
Laser Direct Writing (LDW), also known as 3D multi-photon laser lithography of resins, is a promising technique for fabricating complex free-form elements, including micro-optical functional components. Regular organic or hybrid (organic–inorganic) resins are often used, with the latter exhibiting better optical characteristics, as [...] Read more.
Laser Direct Writing (LDW), also known as 3D multi-photon laser lithography of resins, is a promising technique for fabricating complex free-form elements, including micro-optical functional components. Regular organic or hybrid (organic–inorganic) resins are often used, with the latter exhibiting better optical characteristics, as well as having the option to be heat-treated into inorganic glass-like structures particularly useful for resilient micro-optics. This work is a continuation of our SZ2080™ calcination development of micro-optics, specifically studying the Laser-Induced Damage Threshold (LIDT). Such sol–gel-derived glass 3D micro-structures, particularly those that undergo heat treatment, have not been well-characterized in this respect. In this pilot study, we investigated the LIDT using the Series-on-One (S-on-1) protocol of functional micro-lenses produced via LDW and subsequently calcinated. Our results demonstrate that the LIDT can be significantly increased, even multiple times, by this approach, thus enhancing the resilience and usefulness of these free-form micro-optics. This work represents the first investigation in terms of LIDT into the impact of calcination on LDW-produced, sol–gel-derived glass micro-structures and provides important insights for the development of robust micro-optical devices. Full article
(This article belongs to the Special Issue Research in Computational Optics)
►▼ Show Figures

Figure 1

11 pages, 6235 KiB  
Communication
Crystalline Flat Surface Recovered by High-Temperature Annealing after Laser Ablation
by Daniel Smith, Soon Hock Ng, Amanda Tang, Tomas Katkus, Daniel Moraru and Saulius Juodkazis
Photonics 2023, 10(5), 594; https://doi.org/10.3390/photonics10050594 - 19 May 2023
Cited by 1 | Viewed by 1300
Abstract
Ultra-short laser pulses (1030 nm/230 fs) were used to laser ablate the surface of crystalline sapphire (Al2O3) at high intensity per pulse 20–200 TW/cm2/pulse. Laser-ablated patterns were annealed at a high temperature of 1500 °C. Surface [...] Read more.
Ultra-short laser pulses (1030 nm/230 fs) were used to laser ablate the surface of crystalline sapphire (Al2O3) at high intensity per pulse 20–200 TW/cm2/pulse. Laser-ablated patterns were annealed at a high temperature of 1500 °C. Surface reconstruction took place, removing the ablation debris field at the edges of ablated pits in oxygen flow (O2 flow). Partial reconstruction of ripples was also observed when multi-pulse ablated surfaces were annealed at high temperature in O2 flow. Back-side ablation of a 0.5-mm-thick Al2O3 produced high surface roughness ∼1μm which was reduced to ∼0.2μm by high-temperature annealing at 1500 °C for 2 h in O2. Improvement of surface quality was due to restructuring of the crystalline surface and sublimation, while the defined 3D shape of a micro-lens was not altered after HTA (no thermal morphing). Full article
(This article belongs to the Special Issue Research in Computational Optics)
►▼ Show Figures

Figure 1

9 pages, 4299 KiB  
Communication
A Deep Learning Framework to Remove the Off-Focused Voxels from the 3D Photons Starved Depth Images
by Suchit Patel, Vineela Chandra Dodda, John T. Sheridan and Inbarasan Muniraj
Photonics 2023, 10(5), 583; https://doi.org/10.3390/photonics10050583 - 17 May 2023
Viewed by 1030
Abstract
Photons Counted Integral Imaging (PCII) reconstructs 3D scenes with both focused and off-focused voxels. The off-focused portions do not contain or convey any visually valuable information and are therefore redundant. In this work, for the first time, we developed a six-ensembled Deep Neural [...] Read more.
Photons Counted Integral Imaging (PCII) reconstructs 3D scenes with both focused and off-focused voxels. The off-focused portions do not contain or convey any visually valuable information and are therefore redundant. In this work, for the first time, we developed a six-ensembled Deep Neural Network (DNN) to identify and remove the off-focused voxels from both the conventional computational integral imaging and PCII techniques. As a preprocessing step, we used the standard Otsu thresholding technique to remove the obvious and unwanted background. We then used the preprocessed data to train the proposed six ensembled DNNs. The results demonstrate that the proposed methodology can efficiently discard the off-focused points and reconstruct a focused-only 3D scene with an accuracy of 98.57%. Full article
(This article belongs to the Special Issue Research in Computational Optics)
►▼ Show Figures

Figure 1

14 pages, 8230 KiB  
Article
Improved Classification of Blurred Images with Deep-Learning Networks Using Lucy-Richardson-Rosen Algorithm
by Amudhavel Jayavel, Shivasubramanian Gopinath, Praveen Periyasamy Angamuthu, Francis Gracy Arockiaraj, Andrei Bleahu, Agnes Pristy Ignatius Xavier, Daniel Smith, Molong Han, Ivan Slobozhan, Soon Hock Ng, Tomas Katkus, Aravind Simon John Francis Rajeswary, Rajesh Sharma, Saulius Juodkazis and Vijayakumar Anand
Photonics 2023, 10(4), 396; https://doi.org/10.3390/photonics10040396 - 03 Apr 2023
Cited by 8 | Viewed by 2200
Abstract
Pattern recognition techniques form the heart of most, if not all, incoherent linear shift-invariant systems. When an object is recorded using a camera, the object information is sampled by the point spread function (PSF) of the system, replacing every object point with the [...] Read more.
Pattern recognition techniques form the heart of most, if not all, incoherent linear shift-invariant systems. When an object is recorded using a camera, the object information is sampled by the point spread function (PSF) of the system, replacing every object point with the PSF in the sensor. The PSF is a sharp Kronecker Delta-like function when the numerical aperture (NA) is large with no aberrations. When the NA is small, and the system has aberrations, the PSF appears blurred. In the case of aberrations, if the PSF is known, then the blurred object image can be deblurred by scanning the PSF over the recorded object intensity pattern and looking for pattern matching conditions through a mathematical process called correlation. Deep learning-based image classification for computer vision applications gained attention in recent years. The classification probability is highly dependent on the quality of images as even a minor blur can significantly alter the image classification results. In this study, a recently developed deblurring method, the Lucy-Richardson-Rosen algorithm (LR2A), was implemented to computationally refocus images recorded in the presence of spatio-spectral aberrations. The performance of LR2A was compared against the parent techniques: Lucy-Richardson algorithm and non-linear reconstruction. LR2A exhibited a superior deblurring capability even in extreme cases of spatio-spectral aberrations. Experimental results of deblurring a picture recorded using high-resolution smartphone cameras are presented. LR2A was implemented to significantly improve the performances of the widely used deep convolutional neural networks for image classification. Full article
(This article belongs to the Special Issue Research in Computational Optics)
►▼ Show Figures

Figure 1

Review

Jump to: Research

22 pages, 7978 KiB  
Review
Advances in Optical Visual Information Security: A Comprehensive Review
by Sachin, Ravi Kumar, Sakshi, Raman Yadav, Salla Gangi Reddy, Anil Kumar Yadav and Phool Singh
Photonics 2024, 11(1), 99; https://doi.org/10.3390/photonics11010099 - 22 Jan 2024
Viewed by 921
Abstract
In the modern era, the secure transmission and storage of information are among the utmost priorities. Optical security protocols have demonstrated significant advantages over digital counterparts, i.e., a high speed, a complex degree of freedom, physical parameters as keys (i.e., phase, wavelength, polarization, [...] Read more.
In the modern era, the secure transmission and storage of information are among the utmost priorities. Optical security protocols have demonstrated significant advantages over digital counterparts, i.e., a high speed, a complex degree of freedom, physical parameters as keys (i.e., phase, wavelength, polarization, quantum properties of photons, multiplexing, etc.) and multi-dimension processing capabilities. This paper provides a comprehensive overview of optical cryptosystems developed over the years. We have also analyzed the trend in the growth of optical image encryption methods since their inception in 1995 based on the data collected from various literature libraries such as Google Scholar, IEEE Library and Science Direct Database. The security algorithms developed in the literature are focused on two major aspects, i.e., symmetric and asymmetric cryptosystems. A summary of state-of-the-art works is described based on these two aspects. Current challenges and future perspectives of the field are also discussed. Full article
(This article belongs to the Special Issue Research in Computational Optics)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-8
Back to TopTop