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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.

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, 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.