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Recently, the novel loop-up table(N-LUT) method to solve the tremendous memory problem of the conventional look-up table (LUT) method as well as to increase the generation speed of hologram patterns has been proposed. But, as the resolution of an input 3-D object is enhanced, the number of object points to be calculated for generation of its hologram pattern also increases, which results in a sharp increase of the computation time. Therefore, in this paper, a new approach for fast generation of the hologram pattern of 3-D object images is proposed by using the block redundancy feature of 3-D object images and the N-LUT method. Experimental results show that in the proposed method the number of object points and the overall computation time have been reduced by 43.3 % and 47.9 %, respectively compared to those of the conventional method for the case of the block size. These good experimental results finally confirm the feasibility of the proposed method.

In this paper, a new method to efficiently generate the 3-D(three-dimensional) video holograms for 3-D moving scenes, which is called here the TSR-N-LUT method, is proposed by the combined use of temporal-spatial redundancy(TSR) of 3-D video images and novel look-up table(N-LUT) technique. That is, in the proposed scheme, with the differential pulse code modulation (DPCM) algorithm, temporally redundancy redundant data in the inter-frame of a 3-D video images are removed between the frames, and then inter-line redundant data in the inter-frame of 3-D video images are also removed by using the DPCM method between the lines. Experimental results show that the proposed method could reduced the number of calculated object points and the calculation time of one object point by 23.72% and 19.55%, respectively on the average compared to the conventional method. Good experimental results with 3-D test moving pictures finally confirmed the feasibility of the proposed method to the fast generation of CGH patterns of the 3-D video images.

In this paper, a new stereo object tracking system using the disparity motion vector (DMV) is presented. In the proposed method, the time-sequential disparity maps are extracted from the sequence of the stereo input image pairs and then, the DMV defined as a disparity difference between two consecutive disparity maps is sequentially estimated from these disparity maps. Just like the motion vectors in the conventional video signals, the DMV provides us with motion information of a moving target by showing a relatively large change of the disparity values in the target areas. Accordingly, using this DMV the target area and its location coordinates can be detected. Basing on these locational data of a moving target, the pan/tilt embedded in the stereo camera system can be controlled and as a result, real-time stereo tracking of a moving target can be achieved. From some experiments with 9 frames of the stereo image pairs having 256 × 256 pixels, it is shown that the proposed DMV-based stereo object tracking system can track the moving target with a relatively low error ratio of about 3.05% on average.

Thus far, a general approach to prevent the occurrence of the red tide phenomena and to minimize its resultant damage is to predict the spread point of the red tide. For that, conventionally a set of microalgae are periodically sampled from several shore areas and their numbers of microalgae per unit area are simply counted to predict the threshold level of the spread point of the red tide. However, this approach cannot foresee a decisive symptom for spreading of the red tide in advance. Accordingly, in this paper, we propose a novel approach for accurate prediction of the spread point of red tide by measuring and analyzing the three-dimensional (3-D) volume information of the microalgae with the digital holographic microscopy (DHM). This volume information of the microalgae can be converted into the thickness information through digital holographic reconstruction. With these thickness data, the volume variations of microalgae in time can be finally measured and analyzed. Experiments with several samples of microalgae may confirm the feasibility of the proposed method in the practical application.

In the conventional visual inspection system with naked eyes, a camera has been mostly employed for detection of scratches or glass dust, so that it may be difficult to discriminate between the high-grade and the low-grade mass components. Therefore, here we propose a novel three-dimensional (3-D) visual inspection scheme for effective detection of defects of the transparent materials based on a digital holographic microscopy, which is optically implemented as a form of transmission-typed shearing interferometer. In the proposed method, quantitative data are obtained by converting the phase information of the transparent touch panel or the substrate glass into its depth or thickness information. Then, by using 3-D data extracted from the depth or thickness information of transparent touch panel or substrate glass, we can accurately discriminate between the high-grade and the low-grade mass components. Experiments with test objects confirm the feasibility of the proposed method in the practical applications. Based on these experimental results, the proposed method expects to improve the production yield rate of the original mother glass of the transparent touch panel or the substrate glass used in the LCM.

As an approach for a 3D real image display system without special glasses, a Fresnel lens-based 3D rear-projection display system is implemented. In this display system, the conventional 2D video image is projected into the air through some projection optics, a screen and a pair of Fresnel lens and as a result, it can form a floating video image having a real depth. But in the conventional floating display system some image distortions might be occurred in the floating image plane, in which a flat screen has been mostly used for providing an adequate input image plane. In this paper, as a new approach to alleviate this image distortion problem, a Fresnel lens-based floating display system employing a curved screen is suggested and some computer simulations and practical experiments are carried out. That is, optimum design parameters of a curved screen for reducing image distortion is found out through some computer simulation using an optics design program of Light Tools and its performance in the floating system is experimentally verified and compared with those of the flat screen. Experimental results with a curved screen shows some decrease of image distortion in the floating image plane by comparing with that of the flat screen. This feasibility test suggests a possibility of implementation of a new Fresnel lens-based 3D projection display system with improved image distortion using a curved screen.

In this paper, as an approach for a wide 3D real image display system without special glasses, a 100" Fresnel lens-based 3D real-projection display system is implemented and its physical size is designed by 2800x2800x1600 mm3 in length, width and depth, respectively. In this display system, the conventional 2D video image is projected into the air through some projection optics and a pair of Fresnel lens and as a result, it can form a floating video image having a real depth. From some experiments with the test video images, the floated 3D video images with some depth have been realistically viewed, in which forward depth of the floated 3D image from the display screen is found to be 35~47 inches and the viewing angle to be 60 degrees, respectively. This feasibility test for the prototype of 100" Fresnel lens-based 3D real image rear-projection display systems suggests a possibility of its practical applications to the 3D advertisements, 3D animations, 3D games and so on.

In this paper, an incoherent holographic 3D imaging and display system usinga modified triangular interferometer is implemented and demonstrated. The incoherent holographic system based-on this modified triangular interferometer employs the superposition of Fresnel zone patterns in which the positions and intensities of the object points are uniquely encoded and from this system the complex holograms without bias and conjugate image for 3D object can be obtained. That is, the light reflected from a 3D object is divided into two beams by a beam splitter and input to the modified triangular interferometer. All patterns of two optical wave that travel the modified triangular interferometer in the clockwise and counterclockwise directions is detected by the CCD camera. Here, four pairs of interference pattern are detected by controlling combination of the waveplates in the modified interferometer system then, a complex hologram pattern without bias and conjugated image can be obtained through the modification process of these four patterns. The Mach-Zehnder interferometer is also employed, in this paper, to reconstruct this complex hologram. The real and imaginary parts of the complex hologram are placed in the upper and the lower arms of the interferometer. The Mach Zehnder intrferometer is used to reconstruct the comeplx hologram. That is, the real and imaginayr parts of a complex hologram are placed in each arm of the interferometer, respectively. And illuminating them coherently and recombining the light passed throught eh transparenceis bytheuse of the beam splitter allows the complex addition to be performed. Then, the desired 3D image is reconstructed through Fresnel diffraction, in which the panel plays a role of a holographic optical element. From some experiments with 3D object of "dies", it is suggested that a practical incoherent holographic 3D imaging and display system using a modifeid triangular interferometer can be implemented, in which the bias and conjugate image problems are alleviated.

As a new approach to implement a function of the conventional lenticular sheet used in the autostereoscopic 3D display system, a VHLS (volume holographic lenticular sheet) is suggested. This VHLS is made by recording the MxN (M: number of view, N: number of window pitch) vertical stripe patterns on a volume holographic recording material using an angular multiplexing method. In the experiment, 4-view VHLS is manufactured by using a Dupont photopolymer (HRF-150-100) and then, a VHLS-based autostereoscopic 3D display system is implemented. 4-view strip patterns of 4 x 256 pixels are synthesized to be an image of 1024 x 768 pixels in GUI (graphic user interface) environment, in which the synthesized image consists of 256 pitches and each pitch is composed of 4 pixels. Then, each strip pattern is sequentially recorded in the photopolymer with the corresponding angular-multiplexed reference beams. Some experimenal results show that 4-view imge patterns are diffracted from a synthesized image through the VHLS and these beams are spatially separated each other on the screen, so that a possibility of implementing a new VHLS-based multiview autostereoscopic 3D display system is suggested.

In this paper, a new high-resolution (XGA) SLM is implemented through modification of a commercial TFT-LCD beam projector and its optical modulation characteristics are analyzed as well. The optic module, projection lamp and cooling fans are removed from the beam projector and instead, the electric circuits to compensate their removal are manufactured and inserted into the beam projector, a new high-resolution SLM is finally implemented. Some experiments on the optical modulation characteristics of the implemented SLM have been carried out by using the Mach-Zehnder interferometer. These experimental results show a good optical linearity in amplitude and phase modulation and as a result, the implemented LC-SLM is suggested as a new low-cost, high-resolution input and filter devices for the optical information processing systems.

In this paper, a photopolymer-based VHOE is optimally manufactured and using this VHOE, an experimental model of the VHOE-based 8-view stereoscopic display system is implemented. That is, the VHOE is optically made by angle-multiplexed recording of 8-view's diffraction gratings in the Dupont's photopolymer(HRF-150-100) using an optimized exposure-time scheduling scheme and then, the VHOE-based 8-view stereoscopic display system is implemented, in which the incident angles of the diffracted reference beams of the VHOE are sequentially synchronized with the respective 8-view stereo images displayed on the LCD panel. From some experimental results using 8-view test images, it is found that 8-view stereo images can be diffracted to the eight different directions corresponding to the incident angles of the reference beams and there is some disparity between the stereo images. From these experimental results, a possibility of implementing the VHOE-based multi-view stereoscopic 3D display system is also suggested.