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Dong J, Li Z, Liu X, Zhong W, Wang G, Liu Q, Song X. High-speed real 3D scene acquisition and 3D holographic reconstruction system based on ultrafast optical axial scanning. OPTICS EXPRESS 2023; 31:21721-21730. [PMID: 37381262 DOI: 10.1364/oe.489175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 05/30/2023] [Indexed: 06/30/2023]
Abstract
The lack of three-dimensional (3D) content is one of the challenges that have been faced by holographic 3D display. Here, we proposed a real 3D scene acquisition and 3D holographic reconstruction system based on ultrafast optical axial scanning. An electrically tunable lens (ETL) was used for high-speed focus shift (up to 2.5 ms). A CCD camera was synchronized with the ETL to acquire multi-focused image sequence of real scene. Then, the focusing area of each multi-focused image was extracted by using Tenengrad operator, and the 3D image were obtained. Finally, 3D holographic reconstruction visible to the naked eye can be achieved by the layer-based diffraction algorithm. The feasibility and effectiveness of the proposed method have been demonstrated by simulation and experiment, and the experimental results agree well with the simulation results. This method will further expand the application of holographic 3D display in the field of education, advertising, entertainment, and other fields.
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Abdelhalim I, Hamdy O, Khattab MA, Abdelkawi S, Hassab Elnaby S, Hassan AA. Evaluating the efficacy of Nd:YAG fourth harmonic (266 nm) in comparison with ArF excimer (193 nm) in laser corneal reshaping: ex vivo pilot study. Int Ophthalmol 2023:10.1007/s10792-023-02708-z. [PMID: 37083872 PMCID: PMC10400703 DOI: 10.1007/s10792-023-02708-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Accepted: 04/09/2023] [Indexed: 04/22/2023]
Abstract
PURPOSE Laser corneal reshaping is a common eye surgery utilized to overcome many vision disorders. Different UV laser wavelengths can be effective in the treatment. However, the ArF excimer laser (193 nm) is the most commonly used due to its high absorption in the cornea. In the current study, we investigate the efficacy of applying a solid-state laser (Nd:YAG fourth harmonic at 266 nm) for the corneal reshaping procedure. METHODS The utilized laser is generated using an optical setup based on a BBO nonlinear crystal which converts the Q-switched laser (532 nm) to its fourth harmonic (266 nm). Different pulse energies were applied with the same number of the shoots on ex vivo rabbit corneas, and the histological effect is studied. Moreover, the possible thermal damage on the treated corneal tissues was inspected via electron microscope. Additionally, the DNA damage on the corneal cells due to the application of the proposed laser was examined and compared with the existing technology (ArF Excimer laser at 193 nm) using the comet assay. RESULTS The histological examination revealed an appropriate ablation result with the minimum thermal effect at 1.5 mJ and 2.0 mJ. The overall results show that applying 50-shoots of the 1.5-mJ pulse energy using the proposed 266-nm solid-state laser produces the optimum ablation effect with the minimum thermal damage, and almost the same DNA damage occurred using the commercial 193-nm ArF excimer laser. CONCLUSION Solid-state laser at 266 nm could be a good alternative to the common 193-nm excimer laser for corneal reshaping procedures.
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Affiliation(s)
- Ibrahim Abdelhalim
- Engineering Applications of Laser Department, The National Institute of Laser Enhanced Sciences, Cairo University, Giza, 12613, Egypt
| | - Omnia Hamdy
- Engineering Applications of Laser Department, The National Institute of Laser Enhanced Sciences, Cairo University, Giza, 12613, Egypt.
| | - Mohamed A Khattab
- Department of Cytology and Histology, Faculty of Veterinary Medicine, Cairo University, Giza, 12211, Egypt
| | - Salwa Abdelkawi
- Vision Science Department, Biophysics and Laser Science Unit, Research Institute of Ophthalmology, Giza, Egypt
| | - Salah Hassab Elnaby
- Engineering Applications of Laser Department, The National Institute of Laser Enhanced Sciences, Cairo University, Giza, 12613, Egypt
| | - Aziza Ahmed Hassan
- Medical Applications of Laser Department, The National Institute of Laser Enhanced Sciences, Cairo University, Giza, 12613, Egypt
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Abdel-Harith M, Abdelazeem RM, Hamdy O, Abdel-Salam Z. Adaptive optics-based wavefront-enhanced laser-induced fluorescence (WELIF) for improved analytical performance. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2023; 15:212-220. [PMID: 36524606 DOI: 10.1039/d2ay01521h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
The current study proposes a novel optical approach based on an adaptive optics (AO) system to enhance the fluorescence intensity in the laser-induced fluorescence (LIF) technique. The proposed method, wavefront-enhanced LIF (WELIF), relies mainly on compensating for the aberrations arising from the excitation-laser wavefront. The AO system consists of an active correction element (deformable mirror (DM)) integrated with a Shack-Hartmann wavefront sensor (SHWFS). The overall system operates in a closed-loop configuration to compensate for the laser beam aberrations in real time. The performance of the interaction of the aberration-free excitation laser beam with solid samples, e.g., bone, leaf, polymer sheet, and with liquid samples, e.g., extra virgin olive oil (EVOO), showed a pronounced improvement in the fluorescence peak intensity. As an analytical application example, detailed WELIF measurements have been performed on five EVOO brands to demonstrate the validity of the new approach. Furthermore, the effectiveness of the proposed system was evaluated by measuring the enhancement factor, i.e., the ratio between the fluorescence peak intensity after aberration compensation (AC) relative to the initial peak intensity before aberration compensation (BC). The results reveal that the fluorescence peak intensities have been enhanced with ranges from 20% to 98% after compensation (AC). Besides, the results were statistically assessed based on the receiver operator characteristic (ROC) curve (84% sensitivity AC and 82% BC) and partial least squares regression, PLSR, with a 0.94 coefficient of determination AC compared to 0.90 BC.
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Affiliation(s)
- Mohamed Abdel-Harith
- Cairo University, Laser Applications in Metrology, Photochemistry and Agriculture Dept, National Institute of Laser Enhanced Science, Egypt.
| | - Rania M Abdelazeem
- Cairo University, Engineering Applications of Lasers Dept, National Institute of Laser Enhanced Science, Egypt
| | - Omnia Hamdy
- Cairo University, Engineering Applications of Lasers Dept, National Institute of Laser Enhanced Science, Egypt
| | - Zienab Abdel-Salam
- Cairo University, Laser Applications in Metrology, Photochemistry and Agriculture Dept, National Institute of Laser Enhanced Science, Egypt.
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Abdelazeem RM, Ghareab Abdelsalam Ibrahim D. Discrimination between normal and cancer white blood cells using holographic projection technique. PLoS One 2022; 17:e0276239. [PMID: 36264929 PMCID: PMC9584458 DOI: 10.1371/journal.pone.0276239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2021] [Accepted: 10/03/2022] [Indexed: 11/15/2022] Open
Abstract
White blood cells (WBCs) play a vital role in the diagnosis of many blood diseases. Such diagnosis is based on the morphological analysis of blood microscopic images which is performed manually by skilled hematologist. However, this method has many drawbacks, such as the dependence on the hematologist's skill, slow performance, and varying accuracy. Therefore, in the current study, a new optical method for discrimination between normal and cancer WBCs of peripheral blood film (PBF) images is presented. This method is based on holographic projection technique which is able to provide an accurate and fast optical reconstruction method of WBCs floating in the air. Besides, it can provide a 3D visualization map of one WBC with its characterization parameters from only a single 2D hologram. To achieve that, at first, WBCs are accurately segmented from the microscopic PBF images using a developed in-house MATLAB code. Then, their associated phase computer-generated holograms (CGHs) are calculated using the well-known iterative Fourier transform algorithm (IFTA). Within the utilized algorithm, a speckle noise reduction technique, based on temporal multiplexing of spatial frequencies, is applied to minimize the speckle noise across the reconstruction plane. Additionally, a special hologram modulation is added to the calculated holograms to provide a 3D visualization map of one WBC, and discriminate normal and cancer WBCs. Finally, the calculated phase-holograms are uploaded on a phase-only spatial light modulator (SLM) for optical reconstruction. The optical reconstruction of such phase-holograms yields precise representation of normal and cancer WBCs. Moreover, a 3D visualization map of one WBC with its characterization parameters is provided. Therefore, the proposed technique can be used as a valuable tool for interpretation and analysis of WBCs, this in turn could provide an improvement in diagnosis and prognosis of blood diseases.
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Affiliation(s)
- Rania M. Abdelazeem
- Engineering Applications of Laser Department, National Institute of Laser Enhanced Sciences “NILES”, Cairo University, Giza, Egypt
- * E-mail:
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Pi D, Liu J, Wang Y. Review of computer-generated hologram algorithms for color dynamic holographic three-dimensional display. LIGHT, SCIENCE & APPLICATIONS 2022; 11:231. [PMID: 35879287 PMCID: PMC9314381 DOI: 10.1038/s41377-022-00916-3] [Citation(s) in RCA: 48] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 06/13/2022] [Accepted: 06/21/2022] [Indexed: 05/20/2023]
Abstract
Holographic three-dimensional display is an important display technique because it can provide all depth information of a real or virtual scene without any special eyewear. In recent years, with the development of computer and optoelectronic technology, computer-generated holograms have attracted extensive attention and developed as the most promising method to realize holographic display. However, some bottlenecks still restrict the development of computer-generated holograms, such as heavy computation burden, low image quality, and the complicated system of color holographic display. To overcome these problems, numerous algorithms have been investigated with the aim of color dynamic holographic three-dimensional display. In this review, we will explain the essence of various computer-generated hologram algorithms and provide some insights for future research.
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Affiliation(s)
- Dapu Pi
- Beijing Engineering Research Center for Mixed Reality and Advanced Display, School of Optics and Photonics, Beijing Institute of Technology, Beijing, 100081, China
| | - Juan Liu
- Beijing Engineering Research Center for Mixed Reality and Advanced Display, School of Optics and Photonics, Beijing Institute of Technology, Beijing, 100081, China.
| | - Yongtian Wang
- Beijing Engineering Research Center for Mixed Reality and Advanced Display, School of Optics and Photonics, Beijing Institute of Technology, Beijing, 100081, China
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Abdelazeem RM, Agour M. Optical inspection of single vision soft contact lenses based on an active adaptive wavefront sensor. APPLIED OPTICS 2022; 61:141-148. [PMID: 35200813 DOI: 10.1364/ao.441289] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 11/28/2021] [Indexed: 06/14/2023]
Abstract
We present an experimental configuration for optical inspection of single vision soft contact lenses based on an active adaptive wavefront sensor. At first, the soft lenses were immersed in a saline filled wet cell to prevent surface deformation during measurements. Thereafter, refractive powers and aberrations were accurately measured before and after correcting illumination laser beam aberrations and wet cell-induced aberrations. The results reveal that there is a significant difference between the measured aberrations and refractive powers before and after aberration compensation. Accordingly, the proposed system is recommended as an optical inspection tool for precise assessment of commercially available contact lenses.
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Aju D., Joseph SS. 3D Reconstruction Methods Purporting 3D Visualization and Volume Estimation of Brain Tumors. INTERNATIONAL JOURNAL OF E-COLLABORATION 2022. [DOI: 10.4018/ijec.290296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This work proposes the Crust algorithm for 3D reconstruction of brain tumor, an effective mechanism in the visualization of tumors for presurgical planning, radiation dose calculation. Despite the promising performance of Crust algorithm in reconstruction of Stanford models, it has not yet been considered in 3D reconstruction of brain tumor. Validation of the results is done using the comparison of the 3D models from two cutting edge techniques namely the Marching Cube and the Alpha shape algorithm. The obtained result shows that Crust algorithm provides the brain tumor model with an average quality of triangle meshes ranging from 0.85 to 0.95. Concerning the visual realism, the quality of Crust algorithm models is higher on comparison to the other models. Precision of tumor volume measurement by convex hull method is analysed by repeatability and reproducibility. The standard deviations of repeatability were between 2.03 % and 3.97 %. The experimental results show that Linear Crust algorithm produces high quality meshes with average quality of equilateral triangles close to 1.
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Affiliation(s)
- Aju D.
- Vellore Institute of Technology, India
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Bori E, Pancani S, Vigliotta S, Innocenti B. Validation and accuracy evaluation of automatic segmentation for knee joint pre-planning. Knee 2021; 33:275-281. [PMID: 34739958 DOI: 10.1016/j.knee.2021.10.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 09/28/2021] [Accepted: 10/12/2021] [Indexed: 02/02/2023]
Abstract
BACKGROUND Proper use of three-dimensional (3D) models generated from medical imaging data in clinical preoperative planning, training and consultation is based on the preliminary proved accuracy of the replication of the patient anatomy. Therefore, this study investigated the dimensional accuracy of 3D reconstructions of the knee joint generated from computed tomography scans via automatic segmentation by comparing them with 3D models generated through manual segmentation. METHODS Three unpaired, fresh-frozen right legs were investigated. Three-dimensional models of the femur and the tibia of each leg were manually segmented using a commercial software and compared in terms of geometrical accuracy with the 3D models automatically segmented using proprietary software. Bony landmarks were identified and used to calculate clinically relevant distances: femoral epicondylar distance; posterior femoral epicondylar distance; femoral trochlear groove length; tibial knee center tubercle distance (TKCTD). Pearson's correlation coefficient and Bland and Altman plots were used to evaluate the level of agreement between measured distances. RESULTS Differences between parameters measured on 3D models manually and automatically segmented were below 1 mm (range: -0.06 to 0.72 mm), except for TKCTD (between 1.00 and 1.40 mm in two specimens). In addition, there was a significant strong correlation between measurements. CONCLUSIONS The results obtained are comparable to those reported in previous studies where accuracy of bone 3D reconstruction was investigated. Automatic segmentation techniques can be used to quickly reconstruct reliable 3D models of bone anatomy and these results may contribute to enhance the spread of this technology in preoperative and operative settings, where it has shown considerable potential.
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Affiliation(s)
- Edoardo Bori
- BEAMS Department, Université Libre de Bruxelles, Bruxelles, Belgium.
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Correction: Three-dimensional visualization of brain tumor progression based accurate segmentation via comparative holographic projection. PLoS One 2021; 16:e0251614. [PMID: 33970964 PMCID: PMC8109771 DOI: 10.1371/journal.pone.0251614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
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