Browsing by Author "Rosen, Joseph"

Now showing 1 - 20 of 23

3D incoherent imaging using an ensemble of sparse self-rotating beams
(Optics Express, 2023) Bleahu, Andrei-ioan; Gopinath, Shivasubramanian; Kahro, Tauno; Angamuthu, Praveen Periyasamy; Rajeswary, Aravind Simon John Francis; Prabhakar, Shashi; Kumar, Ravi; Salla, Gangi Reddy; Singh, Ravindra P.; Kukli, Kaupo; Tamm, Aile; Rosen, Joseph; Anand, Vijayakumar
Interferenceless coded aperture correlation holography (I-COACH) is one of the simplest incoherent holography techniques. In I-COACH, the light from an object is modulated by a coded mask, and the resulting intensity distribution is recorded. The 3D image of the object is reconstructed by processing the object intensity distribution with the pre-recorded 3D point spread intensity distributions. The first version of I-COACH was implemented using a scattering phase mask, which makes its implementation challenging in light-sensitive experiments. The I-COACH technique gradually evolved with the advancement in the engineering of coded phase masks that retain randomness but improve the concentration of light in smaller areas in the image sensor. In this direction, I-COACH was demonstrated using weakly scattered intensity patterns, dot patterns and recently using accelerating Airy patterns, and the case with accelerating Airy patterns exhibited the highest SNR. In this study, we propose and demonstrate I-COACH with an ensemble of self-rotating beams. Unlike accelerating Airy beams, self-rotating beams exhibit a better energy concentration. In the case of self-rotating beams, the uniqueness of the intensity distributions with depth is attributed to the rotation of the intensity pattern as opposed to the shifts of the Airy patterns, making the intensity distribution stable along depths. A significant improvement in SNR was observed in optical experiments.
3D single shot lensless incoherent optical imaging using coded phase aperture system with point response of scattered airy beams
(Scientific Reports, 2023) Kumar, Ravi; Anand, Vijayakumar; Rosen, Joseph
Interferenceless coded aperture correlation holography (I-COACH) techniques have revolutionized the field of incoherent imaging, offering multidimensional imaging capabilities with a high temporal resolution in a simple optical configuration and at a low cost. The I-COACH method uses phase modulators (PMs) between the object and the image sensor, which encode the 3D location information of a point into a unique spatial intensity distribution. The system usually requires a one-time calibration procedure in which the point spread functions (PSFs) at different depths and/or wavelengths are recorded. When an object is recorded under identical conditions as the PSF, the multidimensional image of the object is reconstructed by processing the object intensity with the PSFs. In the previous versions of I-COACH, the PM mapped every object point to a scattered intensity distribution or random dot array pattern. The scattered intensity distribution results in a low SNR compared to a direct imaging system due to optical power dilution. Due to the limited focal depth, the dot pattern reduces the imaging resolution beyond the depth of focus if further multiplexing of phase masks is not performed. In this study, I-COACH has been realized using a PM that maps every object point into a sparse random array of Airy beams. Airy beams during propagation exhibit a relatively high focal depth with sharp intensity maxima that shift laterally following a curved path in 3D space. Therefore, sparse, randomly distributed diverse Airy beams exhibit random shifts with respect to one another during propagation, generating unique intensity distributions at different distances while retaining optical power concentrations in small areas on the detector. The phase-only mask displayed on the modulator was designed by random phase multiplexing of Airy beam generators. The simulation and experimental results obtained for the proposed method are significantly better in SNR than in the previous versions of I-COACH.
4D imaging using accelerating airy beams and nonlinear reconstruction
(2023) Bleahu, Andrei; Gopinath, Shivasubramanian; Anand, Vijayakumar; Rosen, Joseph; Juodkazis, Saulius; Tamm, Aile; Kukli, Kaupo; Rajeswary, Aravind Simon John Francis; Katkus, Tomas; Pristy, Agnes; Ng, Soon Hock; Praveen, P. A.; Kahro, Tauno; Smith, Daniel; Arokiaraj, Francis Gracy; Kumar, Ravi
Coded Aperture-Based Self-wavefront Interference Using Transverse Splitting Holography
(2023 International Conference on Next Generation Electronics (NEleX), 2023) Joshi, Narmada; Xavier, Agnes Pristy Ignatius; Arockiaraj, Francis Gracy; Rajeswary, Aravind Simon John Francis; Juodkazis, Saulius; Rosen, Joseph; Tamm, Aile; Anand, Vijayakumar
Self-wavefront interference transverse splitting holography (SWITSH) is a recently developed holographic technique to solve a fundamental problem in the manufacturing of large-area diffractive lenses. In SWITSH, a low NA diffractive lens modulates the light from an object, and the modulated light is interfered with light from the same object that reaches beyond the aperture of the diffractive lens. The resulting self-interference hologram is processed with the pre-recorded point spread hologram using the Lucy-Richardson-Rosen algorithm. Since the self-interference hologram is formed by collecting light beyond the NA of the diffractive lens, it acquires the object information corresponding to the higher spatial frequencies of the object. Consequently, a higher imaging resolution is obtained in SWITSH compared to that of direct imaging with a diffractive lens. In the proof-of-concept study, a resolution improvement of an order was demonstrated. However, the optical architecture of the first version of SWITSH was not optimal, as the strength of the self-interference signal was weak. In this study, we improve SWITSH using different coded apertures, such as axicon and spiral element. An improvement in the strength of the self-interference signal was noticed with the axicon and spiral element. Simulation and experimental results using a diffractive lens, axicon and spiral element are presented.
Computational Imaging Using Deterministic Optical Fields and Non-linear Reconstruction
(Imaging and Applied Optics Congress 2022 (3D, AOA, COSI, ISA, pcAOP), 2022) Arockiaraj, Francis Gracy; Selva, Shakina Jothi; Inbanathan, Stephen Rajkumar; Kamalam, Manueldoss Beaula Ruby; Rajeswary, Aravind Simon John Francis; Anand, Vijayakumar; Rosen, Joseph
Computational imaging techniques are indirect ones consisting of two steps: optical recording and computational reconstruction. In this study, deterministic optical fields such as Bessel, Airy, Gaussian and Laguerre-Gaussian were studied in this indirect imaging framework.
Enhanced design of multiplexed coded masks for Fresnel incoherent correlation holography
(Scientific Reports, 2023) Gopinath, Shivasubramanian; Bleahu, Andrei; Kahro, Tauno; Rajeswary, Aravind Simon John Francis; Kumar, Ravi; Kukli, Kaupo; Tamm, Aile; Rosen, Joseph; Anand, Vijayakumar
Fresnel incoherent correlation holography (FINCH) is a well-established incoherent digital holography technique. In FINCH, light from an object point splits into two, differently modulated using two diffractive lenses with different focal distances and interfered to form a self-interference hologram. The hologram numerically back propagates to reconstruct the image of the object at different depths. FINCH, in the inline configuration, requires at least three camera shots with different phase shifts between the two interfering beams followed by superposition to obtain a complex hologram that can be used to reconstruct an object’s image without the twin image and bias terms. In general, FINCH is implemented using an active device, such as a spatial light modulator, to display the diffractive lenses. The first version of FINCH used a phase mask generated by random multiplexing of two diffractive lenses, which resulted in high reconstruction noise. Therefore, a polarization multiplexing method was later developed to suppress the reconstruction noise at the expense of some power loss. In this study, a novel computational algorithm based on the Gerchberg-Saxton algorithm (GSA) called transport of amplitude into phase (TAP-GSA) was developed for FINCH to design multiplexed phase masks with high light throughput and low reconstruction noise. The simulation and optical experiments demonstrate a power efficiency improvement of ~ 150 and ~ 200% in the new method in comparison to random multiplexing and polarization multiplexing, respectively. The SNR of the proposed method is better than that of random multiplexing in all tested cases but lower than that of the polarization multiplexing method.
Enhanced design of pure phase greyscale diffractive optical elements by phase-retrieval-assisted multiplexing of complex functions
(2023) Gopinath, Shivasubramanian; Bleahu, Andrei; Kahro, Tauno; Rajeswary, Aravind Simon John Francis; Kumar, Ravi; Kukli, Kaupo; Tamm, Aile; Rosen, Joseph; Anand, Vijayakumar
Holographic solution to a fundamental problem in diffractive optics: resolution beyond diffraction and lithography limits
(2023) Bleahu, Andrei; Gopinath, Shivasubramanian; Xavier, Agnes Pristy Ignatius; Kahro, Tauno; Reddy, Andra Naresh Kumar; Arockiaraj, Francis Gracy; Smith, Daniel; Ng, Soon Hock; Katkus, Tomas; Rajeswary, Aravind Simon John Francis; Angamuthu, Praveen Periyasami; Pikker, Siim; Kukli, Kaupo; Tamm, Aile; Juodkazis, Saulius; Rosen, Joseph; Anand, Vijayakumar
Incoherent Digital Holography using Spiral Rotating Point Spread Functions Created by Double-helix Beams
(Digital Holography and 3-D Imaging 2022, 2022) Dubey, Nitin; Anand, Vijayakumar; Khonina, Svetlana; Kumar, Ravi; Reddy, Andra Naresh Kumar; Rosen, Joseph
A new incoherent 3D imaging system with a rotating point spread function has been developed. Different computational reconstruction methods such as non-linear reconstruction and the Lucy-Richardson-Rosen algorithm were tested, and their performances were compared.
Incoherent nonlinear deconvolution using an iterative algorithm for recovering limited-support images from blurred digital photographs
(Optics Express, 2024) Rosen, Joseph; Anand, Vijayakumar
Recovering original images from blurred images is a challenging task. We propose a new deconvolution method termed incoherent nonlinear deconvolution using an iterative algorithm (INDIA). Two inputs are introduced into the algorithm: one is a random or engineered point spread function of the scattering system, and the other is a blurred or distorted image of some object produced from this system. The two functions are Fourier transformed, and their phase distributions are processed independently of their magnitude. The algorithm yields the image of the original object with reduced blurring effects. The results of the new method are compared to two linear and two nonlinear algorithms under various types of blurs. The root mean square error and structural similarity between the original and recovered images are chosen as the comparison criteria between the five different algorithms. The simulation and experimental results confirm the superior performance of INDIA compared to the other tested deblurring methods.
Incoherent nonlinear deconvolution using an iterative algorithm for recovering limited-support images from blurred digital photographs
(2024) Rosen, Joseph; Anand, Vijayakumar
Recovering original images from blurred images is a challenging task. We propose a new deconvolution method termed incoherent nonlinear deconvolution using an iterative algorithm (INDIA). Two inputs are introduced into the algorithm: one is a random or engineered point spread function of the scattering system, and the other is a blurred or distorted image of some object produced from this system. The two functions are Fourier transformed, and their phase distributions are processed independently of their magnitude. The algorithm yields the image of the original object with reduced blurring effects. The results of the new method are compared to two linear and two nonlinear algorithms under various types of blurs. The root mean square error and structural similarity between the original and recovered images are chosen as the comparison criteria between the five different algorithms. The simulation and experimental results confirm the superior performance of INDIA compared to the other tested deblurring methods.
Interferenceless coded aperture correlation holography: history, development, and applications
(2023) Rosen, Joseph; Anand, Vijayakumar
Interferenceless incoherent digital holography with binary coded apertures optimized using direct binary search
(Elsevier B.V., 2022) Kumar, Manoj; Anand, Vijayakumar; Rosen, Joseph
Coded aperture correlation holography offers 3D imaging with improved lateral and axial resolutions. This study is an additional advancement in the line of imaging systems with a pseudorandom coded aperture. Starting with the coded aperture correlation holography system implemented on an incoherent on-axis interferometer, we proposed interferenceless and lensless versions of the system. In the present study, we propose replacing the multi-values phase aperture mask with a binary mask. Two binary masks synthesized iteratively are used in two camera shots. Each mask is obtained from an iterative optimization process known as direct binary search, where the optimized cost function is the peak-to-background ratio of a reconstructed point object. Overall, the system demonstrates a lower background noise compared to other methods, enabling 3D imaging capability with only two camera shots, a substantial improvement in comparison to the many shots in the original systems. Using binary masks might extend the usefulness of the coded aperture holography for new regions in the electromagnetic spectrum other than the visual band, as of X-ray and THz bands.
Interferenceless incoherent digital holography with binary coded apertures optimized using direct binary search
(2023) Kumar, Manoj; Anand, Vijayakumar; Rosen, Joseph
Coded aperture correlation holography offers 3D imaging with improved lateral and axial resolutions. This study is an additional advancement in the line of imaging systems with a pseudorandom coded aperture. Starting with the coded aperture correlation holography system implemented on an incoherent on-axis interferometer, we proposed interferenceless and lensless versions of the system. In the present study, we propose replacing the multi-values phase aperture mask with a binary mask. Two binary masks synthesized iteratively are used in two camera shots. Each mask is obtained from an iterative optimization process known as direct binary search, where the optimized cost function is the peak-to-background ratio of a reconstructed point object. Overall, the system demonstrates a lower background noise compared to other methods, enabling 3D imaging capability with only two camera shots, a substantial improvement in comparison to the many shots in the original systems. Using binary masks might extend the usefulness of the coded aperture holography for new regions in the electromagnetic spectrum other than the visual band, as of X-ray and THz bands.
Nonlinear Reconstruction of Images from Patterns Generated by Deterministic or Random Optical Masks—Concepts and Review of Research
(Journal of Imaging, 2022) Smith, Daniel; Gopinath, Shivasubramanian; Arockiaraj, Francis Gracy; Reddy, Andra Naresh Kumar; Balasubramani, Vinoth; Kumar, Ravi; Dubey, Nitin; Ng, Soon Hock; Katkus, Tomas; Selva, Shakina Jothi; Renganathan, Dhanalakshmi; Kamalam, Manueldoss Beaula Ruby; Rajeswary, Aravind Simon John Francis; Navaneethakrishnan, Srinivasan; Inbanathan, Stephen Rajkumar; Valdma, Sandhra-Mirella; Praveen, Periyasamy Angamuthu; Amudhavel, Jayavel; Kumar, Manoj; Ganeev, Rashid A.; Magistretti, Pierre J.; Depeursinge, Christian; Juodkazis, Saulius; Rosen, Joseph; Anand, Vijayakumar
Indirect-imaging methods involve at least two steps, namely optical recording and computational reconstruction. The optical-recording process uses an optical modulator that transforms the light from the object into a typical intensity distribution. This distribution is numerically processed to reconstruct the object’s image corresponding to different spatial and spectral dimensions. There have been numerous optical-modulation functions and reconstruction methods developed in the past few years for different applications. In most cases, a compatible pair of the optical-modulation function and reconstruction method gives optimal performance. A new reconstruction method, termed nonlinear reconstruction (NLR), was developed in 2017 to reconstruct the object image in the case of optical-scattering modulators. Over the years, it has been revealed that the NLR can reconstruct an object’s image modulated by an axicons, bifocal lenses and even exotic spiral diffractive elements, which generate deterministic optical fields. Apparently, NLR seems to be a universal reconstruction method for indirect imaging. In this review, the performance of NLR is investigated for many deterministic and stochastic optical fields. Simulation and experimental results for different cases are presented and discussed
Optical Imaging Using Coded Aperture Correlation Holography (COACH) with PSF of Spatial-Structured Longitudinal Light Beams—A Study Review
(2024) Rosen, Joseph; Anand, Vijayakumar
Spatial-structured longitudinal light beams are optical fields sculpted in three-dimensional (3D) space by diffractive optical elements. These beams have been recently suggested for use in improving several imaging capabilities, such as 3D imaging, enhancing image resolution, engineering the depth of field, and sectioning 3D scenes. All these imaging tasks are performed using coded aperture correlation holography systems. Each system designed for a specific application is characterized by a point spread function of a different spatial-structured longitudinal light beam. This article reviews the topic of applying certain structured light beams for optical imaging.
Review of engineering techniques in chaotic coded aperture imagers
(2022) Anand, Vijayakumar; Rosen, Joseph; Juodkazis, Saulius
Coded aperture imaging (CAI) is a technique to image three-dimensional scenes with special controlled abilities. In this review, we survey several recently proposed techniques to control the parameters of CAI by engineering the aperture of the system. The prime architectures of these indirect methods of imaging are reviewed. For each design, we mention the relevant application of the CAI recorders and summarize this overview with a general perspective on this research topic.
Roadmap of incoherent digital holography
(Applied Physics B, 2022) Tahara, Tatsuki; Zhang, Yaping; Rosen, Joseph; Anand, Vijayakumar; Cao, Liangcai; Wu, Jiachen; Koujin, Takako; Matsuda, Atsushi; Ishii, Ayumi; Kozawa, Yuichi; Okamoto, Ryo; Oi, Ryutaro; Nobukawa, Teruyoshi; Choi, Kihong; Imbe, Masatoshi; Poon, Ting-Chung
This roadmap article focuses on spatially incoherent digital holography (IDH). Representative IDH methods such as optical scanning holography (OSH), Fresnel incoherent correlation holography (FINCH), coded aperture correlation holography (COACH), IDH with a Fresnel zone aperture, and IDH with an interferometer along with a state-of-the-art optical device are introduced as modern IDH methods. We describe these IDH techniques with applications of three-dimensional (3D) imagers, 3D thermography, and 3D microscopy.
Roadmap of incoherent digital holography
(2022) Tahara, Tatsuki; Zhang, Yaping; Rosen, Joseph; Anand, Vijayakumar; Cao, Liangcai; Wu, Jiachen; Koujin, Takako; Matsuda, Atsushi; Ishii, Ayumi; Kozawa, Yuichi; Okamoto, Ryo; Oi, Ryutaro; Nobukawa, Teruyoshi; Choi, Kihong; Imbe, Masatoshi; Poon, Ting‑Chung
Roadmap on chaos-inspired imaging technologies (CI2-Tech)
(Springer Nature, 2022) Rosen, Joseph; de Aguiar, H.B.; Anand, V.; Baek, Y.; Gigan, S.; Horisaki, R.; Hugonnet, H.; Juodkazis, S.; Lee, K.; Liang, H.; Liu, Y.
In recent years, rapid developments in imaging concepts and computational methods have given rise to a new generation of imaging technologies based on chaos. These chaos-inspired imaging technologies (CI2-Tech) consist of two directions: non-invasive and invasive. Non-invasive imaging, a much older research direction with a goal of imaging through scattering layers, has reached faster, smarter, and sharper imaging capabilities in recent years. The invasive imaging direction is based on exploiting the chaos to achieve imaging characteristics and increase dimensionalities beyond the limits of conventional imagers. In this roadmap, the current and future challenges in invasive and non-invasive imaging technologies are presented.