무안경식 3 차원 디스플레이와 투사형 디스플레이를 이용한 깊이 융합 디스플레이의 관찰 특성 향상

학위논문 (박사)-- 서울대학교 대학원 : 전기·컴퓨터공학부, 2015. 8. 이병호.In this dissertation, various methods for enhancing the viewing characteristics of the depth-fused display are proposed with combination of projection-type displays or integral imaging display technologies. Depth-fused display (DFD) is one kind of the volumetric three-dimensional (3D) displays composed of multiple slices of depth images. With a proper weighting to the luminance of the images on the visual axis of the observer, it provides continuous change of the accommodation within the volume confined by the display layers. Because of its volumetric property depth-fused 3D images can provide very natural volumetric images, but the base images should be located on the exact positions on the viewing axis, which gives complete superimpose of the images. If this condition is not satisfied, the images are observed as two separated images instead of continuous volume. This viewing characteristic extremely restricts the viewing condition of the DFD resulting in the limited applications of DFDs. While increasing the number of layers can result in widening of the viewing angle and depth range by voxelizing the reconstructed 3D images, the required system complexity also increases along with the number of image layers. For solving this problem with a relatively simple configuration of the system, hybrid techniques are proposed for DFDs. The hybrid technique is the combination of DFD with other display technologies such as projection-type displays or autostereoscopic displays. The projection-type display can be combined with polarization-encoded depth method for projection of 3D information. Because the depth information is conveyed by polarization states, there is no degradation in spatial resolution or video frame in the reconstructed 3D images. The polarized depth images are partially selected at the stacked polarization selective screens according to the given depth states. As the screen does not require any active component for the reconstruction of images, projection part and reconstruction part can be totally separated. Also, the projection property enables the scalability of the reconstructed images like a conventional projection display, which can give immersive 3D experience by providing large 3D images. The separation of base images due to the off-axis observation can be compensated by shifting the base images along the viewers visual axis. It can be achieved by adopting multi-view techniques. While conventional multi-view displays provide different view images for different viewers positions, it can be used for showing shifted base images for DFD. As a result, multiple users can observe the depth-fused 3D images at the same time. Another hybrid method is the combination of floating method with DFD. Convex lens can optically translate the depth position of the object. Based on this principle, the optical gap between two base images can be extended beyond the physical dimension of the images. Employing the lens with a short focal length, the gap between the base images can be greatly reduced. For a practical implementation of the system, integral imaging method can be used because it is composed of array of lenses. The floated image can be located in front of the lens as well as behind the lens. Both cases result in the expansion of depth range beyond the physical gap of base images, but real-mode floating enables interactive application of the DFD. In addition to the expansion of depth range, the viewing angle of the hybrid system can be increased by employing tracking method. Viewer tracking method also enables dynamic parallax for the DFD with real-time update of base images along with the viewing direction of the tracked viewers. Each chapter of this dissertation explains the theoretical background of the proposed hybrid method and demonstrates the feasibility of the idea with experimental systems.Abstract i Contents iv List of Figures vi List of Tables xii Chapter 1 Introduction 1 1.1 Overview of three-dimensional displays 1 1.2 Motivation 7 1.3 Scope and organization 9 Chapter 2 Multi-layered depth-fused display with projection-type display 10 2.1 Introduction 10 2.2 Polarization-encoded depth information for depth-fused display 12 2.3 Visualization with passive scattering film 16 2.4 Summary 30 Chapter 3 Compact depth-fused display with enhanced depth and viewing angle 31 3.1 Introduction 31 3.2 Enhancement of viewing characteristics 34 3.2.1 Viewing angle enhancement using multi-view method 34 3.2.2 Depth enhancement using integral imaging 37 3.2.3 Depth and viewing angle enhancement 39 3.3 Implementation of experimental system with enhanced viewing parameters 44 3.4 Summary 51 Chapter 4 Real-mode depth-fused display with viewer tracking 52 4.1 Introduction 52 4.2 Viewer tracking method 55 4.2.1 Viewer-tracked depth-fused display 55 4.2.2 Viewer-tracked integral imaging for a depth-fused display 58 4.3 Implementation of viewer-tracked integral imaging 63 4.4 Summary 71 Chapter 5 Conclusion 72 Bibliography 74 초록 83Docto

Image overlay surgery based on augmented reality : a systematic review

Acknowledgements We thank the staff of the Medical Library of the University of Aberdeen for their advice and Prof. Jennifer Cleland and Dr Jenny Gregory for discussion and support. This work was funded by the Roland Sutton Academic Trust (0053/R/17) and an Elphinstone PhD Scholarship from the University of Aberdeen.Postprin

A Review and Selective Analysis of 3D Display Technologies for Anatomical Education

The study of anatomy is complex and difficult for students in both graduate and undergraduate education. Researchers have attempted to improve anatomical education with the inclusion of three-dimensional visualization, with the prevailing finding that 3D is beneficial to students. However, there is limited research on the relative efficacy of different 3D modalities, including monoscopic, stereoscopic, and autostereoscopic displays. This study analyzes educational performance, confidence, cognitive load, visual-spatial ability, and technology acceptance in participants using autostereoscopic 3D visualization (holograms), monoscopic 3D visualization (3DPDFs), and a control visualization (2D printed images). Participants were randomized into three treatment groups: holograms (n=60), 3DPDFs (n=60), and printed images (n=59). Participants completed a pre-test followed by a self-study period using the treatment visualization. Immediately following the study period, participants completed the NASA TLX cognitive load instrument, a technology acceptance instrument, visual-spatial ability instruments, a confidence instrument, and a post-test. Post-test results showed the hologram treatment group (Mdn=80.0) performed significantly better than both 3DPDF (Mdn=66.7, p=.008) and printed images (Mdn=66.7, p=.007). Participants in the hologram and 3DPDF treatment groups reported lower cognitive load compared to the printed image treatment (p \u3c .01). Participants also responded more positively towards the holograms than printed images (p \u3c .001). Overall, the holograms demonstrated significant learning improvement over printed images and monoscopic 3DPDF models. This finding suggests additional depth cues from holographic visualization, notably head-motion parallax and stereopsis, provide substantial benefit towards understanding spatial anatomy. The reduction in cognitive load suggests monoscopic and autostereoscopic 3D may utilize the visual system more efficiently than printed images, thereby reducing mental effort during the learning process. Finally, participants reported positive perceptions of holograms suggesting implementation of holographic displays would be met with enthusiasm from student populations. These findings highlight the need for additional studies regarding the effect of novel 3D technologies on learning performance

Stereoscopic 3D Technologies for Accurate Depth Tasks: A Theoretical and Empirical Study

In the last decade an increasing number of application fields, including medicine, geoscience and bio-chemistry, have expressed a need to visualise and interact with data that are inherently three-dimensional. Stereoscopic 3D technologies can offer a valid support for these operations thanks to the enhanced depth representation they can provide. However, there is still little understanding of how such technologies can be used effectively to support the performance of visual tasks based on accurate depth judgements. Existing studies do not provide a sound and complete explanation of the impact of different visual and technical factors on depth perception in stereoscopic 3D environments. This thesis presents a new interpretative and contextualised analysis of the vision science literature to clarify the role of di®erent visual cues on human depth perception in such environments. The analysis identifies luminance contrast, spatial frequency, colour, blur, transparency and depth constancies as influential visual factors for depth perception and provides the theoretical foundation for guidelines to support the performance of accurate stereoscopic depth tasks. A novel assessment framework is proposed and used to conduct an empirical study to evaluate the performance of four distinct classes of 3D display technologies. The results suggest that 3D displays are not interchangeable and that the depth representation provided can vary even between displays belonging to the same class. The study also shows that interleaved displays may suffer from a number of aliasing artifacts, which in turn may affect the amount of perceived depth. The outcomes of the analysis of the influential visual factors for depth perception and the empirical comparartive study are used to propose a novel universal 3D cursor prototype suitable to support depth-based tasks in stereoscopic 3D environments. The contribution includes a number of both qualitative and quantitative guidelines that aim to guarantee a correct perception of depth in stereoscopic 3D environments and that should be observed when designing a stereoscopic 3D cursor

The value of Augmented Reality in surgery — A usability study on laparoscopic liver surgery

Augmented Reality (AR) is considered to be a promising technology for the guidance of laparoscopic liver surgery. By overlaying pre-operative 3D information of the liver and internal blood vessels on the laparoscopic view, surgeons can better understand the location of critical structures. In an effort to enable AR, several authors have focused on the development of methods to obtain an accurate alignment between the laparoscopic video image and the pre-operative 3D data of the liver, without assessing the benefit that the resulting overlay can provide during surgery. In this paper, we present a study that aims to assess quantitatively and qualitatively the value of an AR overlay in laparoscopic surgery during a simulated surgical task on a phantom setup. We design a study where participants are asked to physically localise pre-operative tumours in a liver phantom using three image guidance conditions — a baseline condition without any image guidance, a condition where the 3D surfaces of the liver are aligned to the video and displayed on a black background, and a condition where video see-through AR is displayed on the laparoscopic video. Using data collected from a cohort of 24 participants which include 12 surgeons, we observe that compared to the baseline, AR decreases the median localisation error of surgeons on non-peripheral targets from 25.8 mm to 9.2 mm. Using subjective feedback, we also identify that AR introduces usability improvements in the surgical task and increases the perceived confidence of the users. Between the two tested displays, the majority of participants preferred to use the AR overlay instead of navigated view of the 3D surfaces on a separate screen. We conclude that AR has the potential to improve performance and decision making in laparoscopic surgery, and that improvements in overlay alignment accuracy and depth perception should be pursued in the future

Review on Augmented Reality in Oral and Cranio-Maxillofacial Surgery: Toward 'Surgery-Specific' Head-Up Displays

In recent years, there has been an increasing interest towards the augmented reality as applied to the surgical field. We conducted a systematic review of literature classifying the augmented reality applications in oral and cranio-maxillofacial surgery (OCMS) in order to pave the way to future solutions that may ease the adoption of AR guidance in surgical practice. Publications containing the terms 'augmented reality' AND 'maxillofacial surgery', and the terms 'augmented reality' AND 'oral surgery' were searched in the PubMed database. Through the selected studies, we performed a preliminary breakdown according to general aspects, such as surgical subspecialty, year of publication and country of research; then, a more specific breakdown was provided according to technical features of AR-based devices, such as virtual data source, visualization processing mode, tracking mode, registration technique and AR display type. The systematic search identified 30 eligible publications. Most studies (14) were in orthognatic surgery, the minority (2) concerned traumatology, while 6 studies were in oncology and 8 in general OCMS. In 8 of 30 studies the AR systems were based on a head-mounted approach using smart glasses or headsets. In most of these cases (7), a video-see-through mode was implemented, while only 1 study described an optical-see-through mode. In the remaining 22 studies, the AR content was displayed on 2D displays (10), full-parallax 3D displays (6) and projectors (5). In 1 case the AR display type is not specified. AR applications are of increasing interest and adoption in oral and cranio-maxillofacial surgery, however, the quality of the AR experience represents the key requisite for a successful result. Widespread use of AR systems in the operating room may be encouraged by the availability of 'surgery-specific' head-mounted devices that should guarantee the accuracy required for surgical tasks and the optimal ergonomics

투명한 매질에서의 광 경로 분석을 이용한 집약적 3차원 디스플레이

학위논문 (박사)-- 서울대학교 대학원 : 전기·컴퓨터공학부, 2017. 2. 이병호.본 박사학위 논문에서는 광학적으로 투명한 매질에서의 광 경로 분석을 바탕으로 집약적인 3차원 디스플레이 시스템을 구현하는 접근 방법에 대하여 논의한다. 3차원 영상 장치를 구성하는 요소와 시청자 사이의 물리적인 거리를 줄이는 것은 집약적인 3차원 디스플레이 시스템을 구현하는 직관적인 방법이다. 또한, 기존 시스템의 크기를 유지하면서 더 많은 양의 3차원 영상 정보를 표현하는 것 또한 집약적 3차원 디스플레이 시스템을 의미한다. 높은 대역폭과 작은 구조를 가진 집약적 3차원 디스플레이 시스템을 구현하기 위하여 다음의 두 가지 광학 현상을 이용한다. 등방성 물질에서의 전반사 특성과 이방성 물질에서의 복굴절 특성이다. 가시광 영역에서 빛을 투과시키는 두 매질의 고유 광학 특성을 기존의 3차원 디스플레이 시스템에 적용하기 위하여 광 경로 추적을 통하여 분석한다. 광 도파로의 전반사 특성은 집약적 다중 투사 3차원 디스플레이 시스템을 구현하기 위하여 사용한다. 투사 광학계의 영상 정보는 광 도파로로 입사, 내부에서 전반사를 통하여 진행하고, 이에 수평 투사 거리는 광 도파로의 두께로 제한된다. 다수의 전반사 이후 영상 정보는 광 도파로의 출사 면을 통해 빠져나가고, 렌즈에 의하여 최적 시청 지점에서 시점을 형성한다. 광 도파로 내부에서의 광 경로를 등가 모델을 통하여 조사하고, 이를 통해 다수의 투사 광학계로부터 생성된 다수의 시점 영상이 왜곡되는 것을 분석하고 보정한다. 10개의 시점을 제공하는 집약적 다중 투사 3차원 디스플레이 시스템을 통해 제안된 방법을 검증한다. 향상된 대역폭 특성을 가진 다중 투사 3차원 디스플레이와 다중 초점 헤드 마운트 디스플레이 구현을 위한 이방성 판을 이용한 편광 다중화 방법을 제안한다. 빛의 편광 상태, 이방성 판의 광축 방향에 따라 광 경로가 달라진다. 측면 방향으로의 광 경로 전환은 다중 투사 3차원 디스플레이 기술과 결합하여 시점을 측면 방향으로 두 배로 증가시킨다. 깊이 방향으로의 광 경로 전환은 헤드 마운트 디스플레이에서 다중 초점 기능을 구현한다. 광 경로 추적 시뮬레이션을 통해 이방성 판의 모양, 광축, 파장 등의 다양한 파라미터 변화에 따른 광 경로 전환을 분석한다. 각각의 기능에 맞도록 설계된 이방성 판과 편광 회전자를 실시간으로 결합하여, 다중 투사 3차원 디스플레이와 다중 초점 헤드 마운트 디스플레이의 대역폭이 2배 증가한다. 각 시스템에 대한 시작품을 제작하고, 제안된 방법을 실험적으로 검증한다. 본 논문에서는 광 도파로와 복굴절 물질을 이용하여 그 광 경로를 분석, 대형의 다중 투사 3차원 디스플레이 시스템과 개인 사용자의 헤드 마운트 디스플레이 시스템의 크기를 감소시키고, 표현 가능한 정보량을 증가시키는 방법을 제안한다. 광 도파로와 이방성 판은 기존의 3차원 디스플레이 시스템과 쉽게 결합이 가능하며, 제안된 방법은 향후 소형뿐만 아니라 중대형 3차원 디스플레이 시스템의 집약화에 기여할 수 있을 것으로 기대된다.This dissertation investigates approaches for realizing compact three-dimensional (3D) display systems based on optical path analysis in optically transparent medium. Reducing the physical distance between 3D display apparatuses and an observer is an intuitive method to realize compact 3D display systems. In addition, it is considered compact 3D display systems when they present more 3D data than conventional systems while preserving the size of the systems. For implementing compact 3D display systems with high bandwidth and minimized structure, two optical phenomena are investigated: one is the total internal reflection (TIR) in isotropic materials and the other is the double refraction in birefringent crystals. Both materials are optically transparent in visible range and ray tracing simulations for analyzing the optical path in the materials are performed to apply the unique optical phenomenon into conventional 3D display systems. An optical light-guide with the TIR is adopted to realize a compact multi-projection 3D display system. A projection image originated from the projection engine is incident on the optical light-guide and experiences multiple folds by the TIR. The horizontal projection distance of the system is effectively reduced as the thickness of the optical light-guide. After multiple folds, the projection image is emerged from the exit surface of the optical light-guide and collimated to form a viewing zone at the optimum viewing position. The optical path governed by the TIR is analyzed by adopting an equivalent model of the optical light-guide. Through the equivalent model, image distortion for multiple view images in the optical light-guide is evaluated and compensated. For verifying the feasibility of the proposed system, a ten-view multi-projection 3D display system with minimized projection distance is implemented. To improve the bandwidth of multi-projection 3D display systems and head-mounted display (HMD) systems, a polarization multiplexing technique with the birefringent plate is proposed. With the polarization state of the image and the direction of optic axis of the birefringent plate, the optical path of rays varies in the birefringent material. The optical path switching in the lateral direction is applied in the multi-projection system to duplicate the viewing zone in the lateral direction. Likewise, a multi-focal function in the HMD is realized by adopting the optical path switching in the longitudinal direction. For illuminating the detailed optical path switching and the image characteristic such as an astigmatism and a color dispersion in the birefringent material, ray tracing simulations with the change of optical structure, the optic axis, and wavelengths are performed. By combining the birefringent material and a polarization rotation device, the bandwidth of both the multi-projection 3D display and the HMD is doubled in real-time. Prototypes of both systems are implemented and the feasibility of the proposed systems is verified through experiments. In this dissertation, the optical phenomena of the TIR and the double refraction realize the compact 3D display systems: the multi-projection 3D display for public and the multi-focal HMD display for individual. The optical components of the optical light-guide and the birefringent plate can be easily combined with the conventional 3D display system and it is expected that the proposed method can contribute to the realization of future 3D display systems with compact size and high bandwidth.Chapter 1 Introduction 10 1.1 Overview of modern 3D display providing high quality 3D images 10 1.2 Motivation of this dissertation 15 1.3 Scope and organization 18 Chapter 2 Compact multi-projection 3D displays with optical path analysis of total internal reflection 20 2.1 Introduction 20 2.2 Principle of compact multi-projection 3D display system using optical light-guide 23 2.2.1 Multi-projection 3D display system 23 2.2.2 Optical light-guide for multi-projection 3D display system 26 2.2.3 Analysis on image characteristics of projection images in optical light-guide 34 2.2.4 Pre-distortion method for view image compensation 44 2.3 Implementation of prototype of multi-projection 3D display system with reduced projection distance 47 2.4 Summary and discussion 52 Chapter 3 Compact multi-projection 3D displays with optical path analysis of double refraction 53 3.1 Introduction 53 3.2 Principle of viewing zone duplication in multi-projection 3D display system 57 3.2.1 Polarization-dependent optical path switching in birefringent crystal 57 3.2.2 Analysis on image formation through birefringent plane-parallel plate 60 3.2.3 Full-color generation of dual projection 64 3.3 Implementation of prototype of viewing zone duplication of multi-projection 3D display system 68 3.3.1 Experimental setup for viewing zone duplication of multi-projection 3D display system 68 3.3.2 Luminance distribution measurement of viewing zone duplication of multi-projection 3D display system 74 3.4 Summary and discussion 79 Chapter 4 Compact multi-focal 3D HMDs with optical path analysis of double refraction 81 4.1 Introduction 81 4.2 Principle of multi-focal 3D HMD system 86 4.2.1 Multi-focal 3D HMD system using Savart plate 86 4.2.2 Astigmatism compensation by modified Savart plate 89 4.2.3 Analysis on lateral chromatic aberration of extraordinary plane 96 4.2.4 Additive type compressive light field display 101 4.3 Implementation of prototype of multi-focal 3D HMD system 104 4.4 Summary and discussion 112 Chapter 5 Conclusion 114 Bibliography 117 Appendix 129 초 록 130Docto

일상용 근안 디스플레이에 대한 연구: 폼 팩터, 시야각, 아이박스, 투명 및 3차원 홀로그래픽 디스플레이

학위논문(박사) -- 서울대학교대학원 : 공과대학 전기·정보공학부, 2021.8. 이병호.The purpose of the display technology is to deliver visual information through light. When the information becomes larger in its amount and more similar to the natural 3D scene, the user will get a more immersive experience. In this point of view, among many 3D display technologies, the near-eye display (NED) can provide the most immersive experience since it utilizes the information in the most efficient way. Nevertheless, the NED devices are still struggling to penetrate the public market because of the bottlenecks of performance in their optical systems. Especially, among the major required performances, the form factor of the NED optical system is the most urgent problem to solve for NED's daily use in public. In this dissertation, three different methods are presented to reduce the form factor of the NEDs while considering the trade-off with the other performances. In Chapter 2, a method to make a glasses-sized virtual reality (VR) NED is presented. While having a thin form factor, other performances are still comparable such as field of view (FOV), eye-box, and resolution. In Chapter 3, a method to reduce the form factor of the holographic NED is presented, which can offer accommodation 3D focus cue. Conventional holographic projection part which required tens of centimeters of path length can be substituted by a 2 mm thick Bragg grating filter. In Chapter 4, a method to reduce the form factor of a holographic optical see-through NED is presented. When the holographic NED is combined with the waveguide image combiner, both the thin and transparent glass-like form factor of waveguide and the capability of 3D holographic display can be acquired. Moreover, this method also can enlarge the narrow eye-box of the holographic NED. The NED technology just started to run. The goal of the daily-use NED seems far but surely it is in a visible future. The author believes the daily-use NED will revolutionize peoples' lifestyles like smartphones have done. Hopefully, these works' effort toward the daily-use NED will contribute to the upcoming future.디스플레이 기술의 목적은 빛을 통해 시각정보를 전달하는 것이다. 디스플레이가 더 많은 양의 정보를 전달하고, 자연스러운 3D 환경과 더 비슷한 정보를 제공할 수 있을 때, 사용자는 몰입감을 경험할 수 있다. 이러한 정보 전달의 관점에서, 근안 디스플레이는 가장 효율적인 방법으로 많은 자유도를 가지면서 정보를 전달할 수 있는 기술이기 때문에, 가장 몰입감 있는 디스플레이 기술이라고 말할 수 있다. 그럼에도 불구하고 근안 디스플레이는 여전히 시장에 침투하기 위해서 고군분투하고 있다. 여기서 광학계 성능이 병목현상이 되고 있다. 특히 여러 성능들 중에서도 폼 팩터는 일상용 근안 디스플레이를 위해서 가장 시급하게 해결해야하는 문제이다. 이 학위논문에서는 근안 디스플레이의 폼팩터를 줄이면서도 다른 성능을 크게 해치지 않을 수 있는 세 가지 방법을 소개한다. 제 2장에서는 안경 크기의 가상현실용 근안 디스플레이를 만드는 방법을 소개한다. 이 시스템은 얇은 폼팩터를 가졌음에도 시야각, 아이박스, 해상도 등의 다른 성능도 크게 훼손되지 않는다. 제 3장에서는 3차원 초점조절반응을 제공할 수 있는 홀로그래픽 근안 디스플레이에서 폼팩터를 줄일 수 있는 방법을 소개한다. 기존 홀로그래픽 투사 광학계는 수십 센티미터의 광경로가 필요했지만, 이 시스템을 2 mm 두께의 Bragg 격자만으로 대체할 수 있다. 제 4장에서는 홀로그래픽 투명 근안 디스플레이에서의 폼팩터를 줄일 수 있는 방법을 소개한다. 홀로그래픽 근안 디스플레이가 광도파로 영상결합기와 결합되면 두 가지 장점을 모두 가질 수 있다. 따라서 광도파로의 투명하고 얇은 폼팩터와 홀로그래픽 디스플레이의 3차원 초점조절반응 제공가능한 특성을 모두 가질 수 있다. 게다가, 이 방법은 홀로그래픽 근안 디스플레이에서 문제가 되었던 좁은 아이박스에 대한 문제도 해결할 수 있다. 근안 디스플레이 기술은 이제 달리기 시작했다. 일상용 근안 디스플레이에 대한 꿈은 멀어보이지만 분명히 보일만한 거리에 있다. 저자는 일상용 근안 디스플레이가 마치 스마트폰이 그랬듯이 사람들의 삶의 방식을 개혁할 것이라고 믿는다. 이 학위논문연구에서의 노력이 다가오는 미래에 기여할 수 있기를 바란다.1 Introduction 1 1.1 Near-eye display (NED) 1 1.1.1 Display and information 1 1.1.2 3D displays and NED 4 1.2 Daily-use NED 9 1.2.1 VR, AR, and daily-use NED 9 1.2.2 Performance of NED optics 11 1.2.3 Priority of performance for daily-use NED 15 1.3 Dissertation overview 17 2 Compact VR NED using optimized lens array 19 2.1 Introduction 19 2.2 Related works 23 2.2.1 Conventional VR optics 23 2.2.2 Pancake VR optics 23 2.2.3 Lenslet array and light field near-eye display 24 2.2.4 Waveguide near-eye displays 24 2.3 Design approach 25 2.3.1 Why conventional VR is bulky 25 2.3.2 Lenslet array and collecting lens 27 2.3.3 Fresnel lens 29 2.3.4 Polarization-based optical folding (pancake lens) 31 2.4 Design space 33 2.4.1 Light field analysis 33 2.4.2 Design parameter selection 36 2.5 Aberration analysis 38 2.5.1 Fresnel lens selection 38 2.5.2 Image distortion 41 2.6 Implementation 43 2.6.1 Benchtop prototype 43 2.6.2 VR glasses prototype 44 2.7 Display result 46 2.7.1 Camera used in experiments 46 2.7.2 FOV and image distortion 47 2.7.3 Eye-box and pupil swim distortion 49 2.7.4 Resolution and chromatic aberration 50 2.7.5 VR glasses prototype 52 2.8 Discussion and future works 53 2.8.1 System thickness 53 2.8.2 Leakage noise 53 2.8.3 Fresnel lens optimization 54 2.8.4 Pupil tracker synchronization 55 2.8.5 See-through display 55 2.9 Conclusion 55 3 Compact holographic projection using Bragg grating noise filter 57 3.1 Introduction 57 3.2 Related works 58 3.3 Principles 59 3.3.1 Angular stop filter (ASF) 59 3.3.2 Noise in a holographic display 60 3.4 Filter design 61 3.4.1 Design of DC angular stop filter (ASF) 61 3.4.2 Design of high-order angular stop filter (ASF) 64 3.5 Experiments 64 3.6 Discussion 69 3.6.1 Effect of ring-shaped filtered region 69 3.6.2 Application to full color holographic display 69 3.7 Conclusion 70 4 Compact holographic AR NED using waveguide image combiner 73 4.1 Introduction 73 4.1.1 Terminology 74 4.2 Trade-offs in conventional holographic see-through NED 75 4.2.1 Optical see-through property and form factor 75 4.2.2 Holographic NED and narrow eye-box 76 4.3 Limitation of conventional waveguide image combiner 78 4.3.1 Basic principle of waveguide image combiner 78 4.3.2 Limitation in providing accommodation 3D focus cue 80 4.4 Principle of holographic waveguide NED 82 4.4.1 Capability of accommodation 3D focus cue 82 4.4.2 Capability of the eye-box shifting 85 4.5 Algorithm 86 4.5.1 Algorithm for input hologram calculation 86 4.5.2 Algorithm for waveguide system measurement 94 4.6 Experimental results 98 4.6.1 Holographic waveguide NED setup 98 4.6.2 Waveguide system model estimation 101 4.6.3 3D waveguide display results 103 4.7 Discussion 104 4.8 Conclusion 106 5 Conclusion 109 Appendix 124 초록 125박