• Journal of information and communication convergence engineering
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• v.13 no.2
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• pp.132-138
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• 2015

Enlarging the horizontal viewing angle is an important feature of integral imaging monitors. Thus far, the horizontal viewing angle has been enlarged in different ways, such as by changing the size of the elemental images or by tilting the lens array in the capture and reconstruction stages. However, these methods are limited by the microlenses used in the capture stage and by the fact that the images obtained cannot be easily projected into different displays. In this study, we upgrade our previously reported method, called SPOC 2.0. In particular, our new approach, which can be called SPOC 2.1, enlarges the viewing angle by increasing the density of the elemental images in the horizontal direction and by an appropriate application of our transformation and reshape algorithm. To illustrate our approach, we have calculated some high-viewing angle elemental images and displayed them on an integral imaging monitor.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.12
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• pp.3055-3062
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• 2014

3D integral imaging technique with an active mask is capable of displaying real 3D images with high resolution in space. In this paper, we present a novel 3D/2D convertible integral imaging display system using an active mask. For the proposed method, the principles of 3D, 2D, and 3D/2D composed operations are explained according to the displayed images through two LCD panels. In 3D mode, the elemental images and the mask images are displayed in two display panels. On the other hand, the light source image and 2D image are displayed in 2D mode. In addition, 3D/2D mode is obtained using the spatial separation for 3D and 2D modes. To show the feasibility of the proposed method, we carry out the preliminary experiments and present the optical results.

• Korean Journal of Bronchoesophagology
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• v.4 no.1
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• pp.43-51
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• 1998

Background： Three-dementional imaging with spiral CT(3D spiral CT) is a well established imaging modality which has been investigated in various clinical settings. However the 3D spiral CT in upper airway disease is rarely reported and its results are still obscure. Objectives： To access the usefulness of 3D spiral CT imaging in patients with upper airway diseases. Materials and Methods We performed 3D spiral CT in fourteen patients In whom upper airway diseases were clinically suspected. Nine of these patients had upper airway stenosis, two had laryngeal cartilage fracture, and three had laryngo-hypopharyngeal cancer. For evaluation of location and extent of the lesions, we compared the findings of 3D imaging with those of air tracheogram, conventional 2D CT images, endoscopic and operative findings. Results： In case of stenosis, 3D spiral CT provide significant useful information, particularly the site and length of the stenotic segment. But, it was difficult to define the fracture of the laryngeal framework and to detect the cartilagenous invasion by head and neck cancer using the 3D imaging. Conclusion : The 3D spiral CT was an useful adjunctive method to assess some kind of upper airway disease but not in others. So, we should compare the findings of 3D images with those of other diagnostic tools for accurate diagnosis of the upper airway disease.

• Investigative Magnetic Resonance Imaging
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• v.19 no.3
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• pp.178-185
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• 2015

Purpose: To compare the frequency of posterior globe flattening between two-dimensional T2-weighted imaging (2D T2WI) and three-dimensional (3D T2WI). Materials and Methods: Sixty-nine patients (31 female; mean age, 44.4 years) who had undergone both 5-mm axial T2WI and sagittal 3D 1-mm isovoxel T2WI of the whole brain for evaluation of various diseases (headache [n = 30], large hemorrhage [n = 19], large tumor or leptomeningeal tumor spread [n = 15], large infarct [n = 3], and bacterial meningitis [n = 2]) were used in this study. Two radiologists independently reviewed both sets of images at separate sessions. Axial T2WI and multi-planar imaging of 3D T2WI were visually assessed for the presence of globe flattening. The optic nerve sheath diameter (ONSD) was measured at a location 4 mm posterior to each globe on oblique coronal imaging reformatted from 3D T2WI. Results: There were significantly more globes showing posterior flattening on 3D T2WI (105/138 [76.1%]) than on 2D T2WI (27/138 [19.6%], P = 0.001). Inter-observer agreement was excellent for both 2D T2WI and 3D T2WI (Cohen's kappa = 0.928 and 0.962, respectively). Intra-class correlation coefficient for the ONSD was almost perfect (Cohen's kappa = 0.839). The globes with posterior flattening had significantly larger ONSD than those without on both 2D and 3D T2WI (P < 0.001; $6.14mm{\pm}0.44$ vs. $5.74mm{\pm}0.44$ on 2D T2WI; $5.90mm{\pm}0.47$ vs. $5.56mm{\pm}0.34$ on 3D T2WI). Optic nerve protrusion was significantly more frequent on reformatted 1-mm 3D T2WI than on 5-mm 2D T2WI (8 out of 138 globes on 3D T2WI versus one on 2D T2WI; P = 0.018). Conclusion: Posterior globe flattening is more frequently observed on 3D T2WI than on 2D T2WI in patients suspected of having increased intracranial pressure. The globes with posterior flattening have significantly larger ONSD than those without.

• The Research Journal of the Costume Culture
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• v.18 no.6
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• pp.1305-1317
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• 2010

This research aim concerns questioning how we can generate environments suggestive of nature fused with built environments through textiles. Through literature reviews and experiments with available the 3D imaging techniques of Holography, Lenticular and other new technologies, We have researched towards finding the most effective method for 3D imaging techniques for textile applications. This objective is to produce intriguing textile patterns and images in which the objects and colours change as viewpoints change. Experimental work was carried out in collaboration with professional textile researchers, scientists, artists and designers conducting research in this field.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.46-49
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• 2005

In this paper, a novel 2D/3D convertible display system based on integral imaging is proposed. Combining two liquid crystal display panels with integral imaging, it is possible to convert the display between two-dimensional mode and three-dimensional mode without mechanical movement. The proposed method is proven by preliminary experiments.

• Journal of the Korean Society for Nondestructive Testing
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• v.34 no.6
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• pp.441-446
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• 2014

A 3D ultrasound image is desired in many medical examinations. However, the implementation of a 2D array, which is needed for a 3D image, is challenging with respect to fabrication, interconnection and cabling. A 2D sparse array, which needs fewer elements than a dense array, is a realistic way to achieve 3D images. Because the number of ways the elements can be placed in an array is extremely large, a method for optimizing the array configuration is needed. Previous research placed the target point far from the transducer array, making it impossible to optimize the array in the operating range. In our study, we focused on optimizing a 2D sparse array transducer for 3D imaging by using a simulated annealing method. We compared the far-field optimization method with the near-field optimization method by analyzing a point-spread function (PSF). The resolution of the optimized sparse array is comparable to that of the dense array.

• Journal of the Korean Society of Hazard Mitigation
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• v.5 no.2 s.17
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• pp.1-8
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• 2005

Microwave tomographic imaging technology using a bi-focusing operator has been developed in order to detect the internal voids/objects inside concrete structures. The imaging system consists of several cylindrical or planar array antennas for transmitting and receiving signals, and a numerical focusing operator is applied to the external signals both in transmitting and in receiving fields. In this study, the authors developed 3-dimensional (3D) electromagnetic (EM) imaging technology to detect such damage and to identify exact location of steel rebars or dowel. The authors have developed sub-surface two-dimensional (2D) imaging technique using tomographic antenna array in previous works. In this study, extending the earlier analytical and experimental works on 2D image reconstruction, a 3D microwave imaging system using tomographic antenna way was developed, and multi-frequency technique was applied to improve quality of the reconstructed image and to reduce background noises. Numerical simulation demonstrated that a sub-surface image can be successfully reconstructed by using the proposed tomographic imaging technology. For the experimental verification, a prototype antenna array was fabricated and tested on a concrete specimen.

• Nuclear Engineering and Technology
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• v.56 no.4
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• pp.1460-1471
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• 2024

2D and 3D ultrasonic imaging has so far not been demonstrated in pure molten lead in the open literature. In this study the development of such an ultrasonic device for imaging is outlined and results from testing at 380 ℃ in lead are presented. The main difficulties were found to be achieving then maintaining suitable wetting while ensuring suitable durability of the device, both due to the harsh nature of molten lead and the elevated temperatures. The successful detection and imaging (2D and 3D), of differently shaped targets, where the features were above the size of the transmitted ultrasound beam was demonstrated.

• Korean Journal of Radiology
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• v.22 no.2
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• pp.243-252
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• 2021

Objective: To compare and correlate the findings of intravoxel incoherent motion (IVIM) magnetic resonance (MR) imaging and arterial spin labeling (ASL) imaging in characterizing parotid gland tumors. Materials and Methods: We retrospectively reviewed 56 patients with parotid gland tumors evaluated by MR imaging. The true diffusion coefficient (D), pseudo-diffusion coefficient (D^*), and fraction of perfusion (f) values of IVIM imaging and tumor-to-parotid gland signal intensity ratio (SIR) on ASL imaging were calculated. Spearman rank correlation coefficient, chi-squared, Mann-Whitney U, and Kruskal-Wallis tests with the post-hoc Dunn-Bonferroni method and receiver operating characteristic curve assessments were used for statistical analysis. Results: Malignant parotid gland tumors showed significantly lower D than benign tumors (p = 0.019). Within subgroup analyses, pleomorphic adenomas (PAs) showed significantly higher D than malignant tumors (MTs) and Warthin's tumors (WTs) (p < 0.001). The D^* of WTs was significantly higher than that of PAs (p = 0.031). The f and SIR on ASL imaging of WTs were significantly higher than those of MTs and PAs (p < 0.05). Significantly positive correlation was found between SIR on ASL imaging and f (r = 0.446, p = 0.001). In comparison with f, SIR on ASL imaging showed a higher area under curve (0.853 vs. 0.891) in discriminating MTs from WTs, although the difference was not significant (p = 0.720). Conclusion: IVIM and ASL imaging could help differentiate parotid gland tumors. SIR on ASL imaging showed a significantly positive correlation with f. ASL imaging might hold potential to improve the ability to discriminate MTs from WTs.