<p>The authors examined the effects of chair swiveling with the psycho-physiological effects of viewing short segments of 360° videos using a head-mounted display (HMD) in terms of the type of content. Twenty participants viewed 360° videos with varying features using an eye-tracking HMD consisting of a smartphone fitted in a case containing optics. Ten participants were seated on a swivel chair and the others on a fixed one. Objective indexes on gaze and body rotation and subjective indexes on simulator sickness, emotional reaction and immersion were measured. It was found that the features of content, especially camera motion, affect psychological effects like discomfort and observation behavior, and chair swiveling affects the behavior looking around, the reception of visual information and emotional response. It turns out that the rotating chair, which is easy to think that it supports the action the user sees, does not necessarily contribute to the user experience.</p>

<p>In this study, the effects on concentration of attention, cognitive activity such as memory was examined in consideration of humans' cognitive characteristic over 3D images about the partial 3D image which changed a part of picture. The experiment of concentration of attention was carried out by measuring reaction time in visual search task using a simple visual target and eye fixation while viewing natural color image. On the other hand, the experiment of cognitive effect such as memory, the searching time until the changes are recognized were computed using the change blindness subject. That needs the cognitive activity of comparing by memorizing a picture temporarily while turning a look for detection of change. As a result, it was suggested by the partial 3D image that an object has the cognitive effect which is easy to go up to consciousness and to remain in memory.</p>

<p>In this research, the effects on preference and visual characteristics were examined on correlations with changing parallax angle conditions in stereoscopic 3D images. Specifically, we investigated the influence of their preference decisions in 2D and 3D conditions as well as the different type of parallax angle including the negative and positive parallaxes. In experiment 1, six novel shapes excluding humans' experience were presented with five types of parallax angles (-0.5, -0.2, 0, 0.2, 0.5 degree). The experiment of paired comparison which selected one from two shapes was conducted and eye movement was measured. As a result, the negative parallax type was preferable to the positive angle, which was influenced by the absolute value of the parallax angles. In experiment 2, the time and numbers of eye fixation were measured by eye movement analysis under the same stimuli and apparatus when performing paired comparison tasks with two types of parallax angles (-0.5 and 0.5 degree). The result was that the time and numbers of eye fixation more increased during viewing negative parallax conditions than positive one.</p>

<p>This paper reports on the effect of the physical state of the body on touch sensations caused by collisions with virtual objects. The collision of a virtual object with a user's body in a virtual environment may cause an illusory touch, or haptic, sensation. We hypothesize that a real-world touch sensation of moving air on skin may augment an illusory touch sensation created by the visual representation of a collision with an object in a virtual scene. To assess this hypothesis, we performed experiments evaluating touch sensation in three conditions: with the user's body covered, with the user's body uncovered, and when blowing air onto the user. Our results showed that a touch sensation was strongly induced in the condition where the user's body was uncovered. Furthermore, the effect of blowing air onto the user differed depending on the body part that was stimulated and the representation of the virtual object. These results suggest that the top-down and bottom-up information for illusory touch sensation such as the user's physical state and the touch sensation of the air on skin had affected each other.</p>

<p>In this study, the authors examined behavioral characteristics during viewing 360-degree (360) images by measuring time-series change of body part rotations. In the experiment, two conditions were prepared. First was the HMD condition which a simple head-mounted display using a smartphone was used, and second was the LCD condition which a LC display with similar viewing angle was used. Four types of still images with different number of gaze targets were presented as the experimental stimuli. Under the two experimental conditions, body part rotations of the participants and subjective indexes on motion sickness and visual fatigue were measured and analyzed. From the results of the experiment, the authors found a common tendency of the late and peak in the time series rotation of body parts. The authors discussed further results of the experiment in terms of the basic tendencies of behavioral changes by viewing 360 images.</p>

This study contained two experimental examinations of the cognitive activities such as visual attention and memory in viewing stereoscopic (3D) images. For this study, partially converted 3D images were used with binocular parallax added to a specific region of the image. In Experiment 1, change blindness was used as a presented stimulus. The visual attention and impact on memory were investigated by measuring the response time to accomplish the given task. In the change blindness task, an 80 ms blank was intersected between the original and altered images, and the two images were presented alternatingly for 240 ms each. Subjects were asked to temporarily memorize the two switching images and to compare them, visually recognizing the difference between the two. The stimuli for four conditions (2D, 3D, Partially converted 3D, distracted partially converted 3D) were randomly displayed for 20 subjects. The results of Experiment 1 showed that partially converted 3D images tend to attract visual attention and are prone to remain in viewer's memory in the area where moderate negative parallax has been added.
In order to examine the impact of a dynamic binocular disparity on partially converted 3D images, an evaluation experiment was conducted that applied learning, distraction, and recognition tasks for 33 subjects. The learning task involved memorizing the location of cells in a 5 x 5 matrix pattern using two different colors. Two cells were positioned with alternating colors, and one of the gray cells was moved up, down, left, or right by one cell width. Experimental conditions was set as a partially converted 3D condition in which a gray cell moved diagonally for a certain period of time with a dynamic binocular disparity added, a 3D condition in which binocular disparity was added to all gray cells, and a 2D condition. The correct response rates for recognition of each task after the distraction task were compared. The results of Experiment 2 showed that the correct response rate in the partial 3D condition was significantly higher with the recognition task than in the other conditions. These results showed that partially converted 3D images tended to have a visual attraction and affect viewer's memory.

The paper introduce a cross-modal illusion of 'weak' tactile sensation. The illusion is induced by image of virtual object that is superimposed on observers' hands using a see-through Head Mounted Display (HMD). Observers can feel the weak tactile sensation with touching and moving the virtual object. This paper reports an experimental evaluation and questionnaire survey of the characteristics of this illusion. The results showed that three dimensional position of the contact of virtual object affected the occurrence of illusion. Furthermore, the results of surveys suggested that the illusion may cause not only the weak tactile but also the warm-cold or wind sensations.

The relationship between differences in individuals' past experience viewing stereoscopic images and their discomfort associated with 3D video was examined. In the current study, 21 subjects were categorized as either inexperienced or experienced viewers of stereoscopic images (12 and 9 subjects, respectively). Two commercially available 3D movies with different depth and motion characteristics were presented to the subjects under two different viewing conditions. Eye discomfort, fatigue in parts of the body, and mental workload were measured. We found that experienced viewers were affected more from moderate depth video with less motion, perhaps because of their higher degree of attention toward subtler depth detail. Experienced viewers reported more severe fatigue in the upper parts of their bodies, which could be attributed to their body adjustments effected in an effort to optimally receive depth information. Inexperienced viewers were affected more by images with more depth and motion, a result perhaps of their initial excitement to experience the new technology. It was shown that particularly depth-emphasized segments demand higher mental workload from experienced viewers, but the effect is transient and not cumulative. It was found that differences between the two groups are exaggerated under the near viewing condition.

本研究では，二眼式立体映像の呈示方式が与える生体影響に関して，基礎的な検討を行った．家庭向けの主要な呈示方式として，時間多重方式と空間多重方式に着目し，各方式において特有のアーチファクトを抽出し，それらの生理・心理的な影響について評価した．具体的に，時間多重方式ではファントムアレイ，偽視差，フリッカ，空間多重方式では，視野闘争，偽視差，解像度低下というアーチファクトを定義し，それらの強度や随伴の容易な単純刺激を用いて実験を行った．結果から，実験刺激によるアーチファクトの生起が確認され，それらが生理・心理的な影響を与え得ることが分かった．そして，アーチファクトの種類による影響の差異や相互作用と同時に，呈示方法の工夫によりアーチファクトを軽減する可能性も示唆された．

近年、唾液中コルチゾールが非侵襲的かつ簡便に用いることができるストレス指標として注目されている。本研究ではパニック障害患者を対象とし、認知行動療法（cognitive-behavioral therapy: CBT）プログラム実施に伴う唾液中コルチゾール分泌の変化を検討した。対象は9名の広場恐怖を伴うパニック障害患者であり、6回のセッションからなるCBTプログラムを実施した。プログラムの導入前と終了後に、質問紙・面接によってパニック障害重症度、回避行動、不安、抑うつ症状、一般性セルフ・エフィカシーを評価した。また導入前と終了後に唾液採取日を設け、一日6回（起床直後、15分後、30分後、3時間後、8時間後、就寝前）の唾液採取を実施した。得られたコルチゾール値から、傾き（直後から就寝前の値を減じたもの）、起床時反応（直後から15分・30分にかけてのコルチゾール反応の総面積）、一日分泌量（直後から8時間後までのコルチゾール分泌の総面積）を算出し、指標とした。分析の結果、プログラム終了後にパニック障害重症度、回避行動、一般性セルフ・エフィカシーが改善するとともに、コルチゾールの傾きが有意に上昇した（t[7]=2.51, p<0.05）。またプログラム前後の変化値をとり、スピアマンの相関分析を行ったところ、パニック障害重症度と一日分泌量（r_s=0.71, p<.05）、状態不安と一日分泌量（r_s=0.78, p<0.05）、状態不安と起床時反応（r_s=0.81, p<0.05）の間に有意な相関が認められ、重症度や不安の低下とともに一日分泌量や起床時反応が低下することが示された。これらの結果はCBTプログラムの効果が生理学的にも簡便に評価できる可能性を示している。唾液中コルチゾールを用いた研究は今後さらに増えると予想され、臨床的な場面でも、生理的評価の手法として、このような指標が積極的に使われることが望まれる。

小学校の識字学習方法では,通常学級に在籍する健常児及び発達性読み書き障害児を問わず同様の学習効果が得られる学習環境は実現していない.本論文は,通常学級に在籍する児童の識字学習支援を目的とし,文字構造の把握を直感的に認識できるようにするための立体視文字ブロックを提案し,その識字効果について検討した.立体視文字ブロックは,特殊な機材を必要とせず,筆順情報に基づき奥行位置が変化するように透過比率を設定した2枚の文字画像を,均一な厚みのある透過基板の前後面に密着させることで立体視可能な文字を再現する.本実験は,低学年の児童を対象とし,実験条件が立体視文字ブロックに表現される立体文字,統制条件が平面上に描かれた二次元の文字とし比較を行った.評価方法は,呈示文字から1字画の形状を弁別可能か,評価課題の正答率及び回答までの反応時間を測定した.実験の結果,健常児においても立体文字が平面文字より字画構成の弁別が容易であることが明らかとなった.

Monocular head-mounted displays (HMDs) will be a major tool for ubiquitous computing. However, monocular HMD visibility causes a decrease in the light received from the environment. Fluctuating light from the environment strongly affects the visibility of images presented on the monocular HMD. In the present study, we have studied a method for controlling HMD backlighting to improve visibility at the wearing a monocular HMD under variable lighting conditions. Three backlight control patterns were developed from Experiment I as psychophysical measurements, and their validities were subjectively evaluated in Experiment II. The results suggest increased visibilities at wearing a monocular HMD when controlling the backlight. Moreover, the rules for backlighting control are based on psychophysical theory.

Virtual Heritage is able to give the real feeling of cultural legacies as if one was actually there. This can be achieved by restoring those legacies which are difficult to experience in our daily lives. In this research, Virtual Heritage construction and evaluation of human model distribution towards its impression were performed. The preference degree of Virtual Heritage according to human model distribution was sought. The evaluation on the change of preference corresponding to the density of human model distribution was performed by focusing on the relation between the human model distribution and the impression change. As a result, it was verified that the human model distribution influences the preference degree, sense of reality, and etc. Under the condition of high density human model arrangement, it was confirmed that there are cases of decreased sense of reality due to the increased sense of pressure.

Recently, activities about the 3D digital archive of cultural heritages become very popular. The development of this technology aims at satisfying the competing ideals of preserving cultural heritage while at the same time making it available to the public. Rich expression by the stereoscopic 3D is suitable for the viewing of 3D data saved culture heritages. In this paper, we report on the work of archiving heritage of Chinese Maijishan Grotto and the developing of stereoscopic VR content for it. In our content, viewers can experience the precious cultural heritage which can't be usually watched. Representation of cultural heritage can be more lifelike by presenting stereoscopic images and interactions. In addition, the results of the subjective evaluation confirmed VR content's reality and 3D effects.

本研究では,発達性読み書き障害(Developmental Dyslexia以下,DD)の特徴的な認知特性と考えられている空間認知能力に着目し,文字に立体的な視覚情報を付加した平仮名の学習方法を考案した.具体的には,平仮名一文字を字画ごとに分解し,それぞれを異なる奥行き位置に配置することで視覚的な情報に書字方法も内包する学習方法である.文字の呈示には,Multi-layered Display(以下,MLD)を用いた.MLDは視覚系の不整合が生じる事なく立体呈示が可能なディスプレイである.立体視の効果を検証するためDD児に平仮名学習を行い評価した.評価方法は,学習前後に書字した字形を定量化し,お手本の字形との近似率を逸脱量を用いて比較する客観評価方法を用いた.評価の結果,学習後に書字した字形の逸脱量が学習前より減少していた.これは識字能力が向上したと考えられ,立体視の効果が示唆された.

本研究では, 光学補正により観察者の調節を適切に作用させられる立体ディスプレイを用いて, 立体映像を観察することによる眼精疲労の回復効果を検討した. 実験1では, 立体映像の観察前後に視力と眼精疲労の自覚症状を測定することで, 回復効果の程度を検討した. そして, 実験2では, 一日中VDT作業を行っている事務職員を被験者として, 朝の測定値および平面映像観察と比較することで回復効果を検討した. また, 被験者の視覚状態に合わせて徐々に遠方視させることを目的とした刺激呈示のフィードバック機能を用いて, 調節の緊張緩和を促した. 実験の結果から, 調節が適切に作用する立体映像は, 平面映像と比較して, 眼精疲労の回復効果が高いことが示された. 本研究で得られた眼精疲労の回復効果は, 一過性の反応であると考えられるが, 見えがはっきりするような感覚や眠気がなくなるような爽快感は, 調節が適切に呈示される立体映像により生じたのだと考察された.

本論文ではユネスコの世界危機遺産であるイランのバム城塞(2003年の地震で破壊)の3次元CG復元とバーチャルリアリティの国際研究プロジェクトについて報告する。地図,写真,ムービー等の多様なデータ源についての分析的,相対的な研究および3DCGの基本データとしての知識ベースを提供する際の情報の欠落についても言及する。城塞の南北2つの主軸に沿って位置する破壊された建造物の3CDGツールを使用したシミュレーションプロセスおよび3DCG復元について述べる。また異なるデータタイプの地図,写真,ムービー,地形データ,スケッチなどを異なったチーム間で同時使用して破壊された建造物の3次元CG復元するプロセスについても述べている。セマンティックな3次元復元を保障するために導入したメタデータベースのレイヤーネイミングによるモデリングの主要なアプローチについても述べる。さらに,現場の複雑な粘土レンガ建造物のモデリングツールについても述べる。また建築学的,歴史的背景を考慮した,3DCG復元の精度を上げるための専門家向けのディジタル資源についても述べる。最後に,本3DCGモデリングの補強,インターネットを使った3DVRの公開などの計画について言及する。

A field-sequential colour projection system can display colour images using a single panel. Such a system, however, produces characteristic trichromatic separation, or "colour breakup". Colour breakup is the perceived splitting of the white portions of an image into its red, green, and blue components when the image is projected with the colour sequential method and the viewer's eyes are moving rapidly. Viewing images containing colour breakup may cause visual fatigue and other symptoms of asthenopia. In this study, the authors examine the various subjective symptoms of asthenopia that can be caused by colour breakup. (c) 2007 Elsevier B.V. All rights reserved.

Recently, attention is being brought to exposure treatment methods using Virtual Reality for those suffering from panic disorder accompanied by agoraphobia. Overseas, contents for exposure treatment introducing Virtual Reality began development in the 1990s and positive evaluations are being made regarding its treatment methods and treatment effects. On one hand, there are still no cases developed professionally in Korea and even evaluations cases introduced into treatment are being made using contents developed overseas. For such reasons, this study has attempted to develop Virtual Reality Exposure contents which fully reflect Japan's culture and environment. Developed contents were focused on subway environments where avoidance was shown the most among patients receiving treatment in community hospitals. Contents were produced through Virtual Reality by modeling existing places and objects in their actual size to express a high sense of reality. Also, mutual interaction functions were strengthened to allow exposure suitable to the diverse symptoms of each patient. Although evaluations through this study are still in progress, changes in avoidance behavior regarding anxiety and fear are being confirmed and treatment effects are being verified through additional experiments.

Monocular head-mounted displays (HMDs) can be used with wearable computers. However, such displays can cause binocular rivalry, a phenomenon in which the left and right images alternate, and is unstable. Binocular rivalry, when using HMD, causes the image of the environment to alternate with the HMD image, or even the total loss of perception of the image from the HMD. Binocular rivalry can occur with displays of any resolution. In this study, we used optokinetic nystagmus (OKN) to reduce binocular rivalry. A special stimulus synchronized to the occurrence of binocular rivalry was used to trigger OKN. The subject was asked to observe a visual stimulus and press a trigger button whenever binocular rivalry occurred. This initiated the presentation of a specific spatial frequency stimulus that broke up the rivalry. Electro-oculogram (EOG) electrodes recorded the observer's possible loss of perception of the HMD image, helping to confirm the occurrence of binocular rivalry. Sixteen subjects participated in the experiments. The results indicate that synchronizing special stimuli to the viewers' responses in order to induce OKN can reduce binocular rivalry.

This paper proposes the safety-education VR contents to make subjects experience the state of cognition that causes accident easily. On the working environment, the accident is often caused by the failure of operation that is called as human error. One of the cause of these error is inappropriate attention management. The ability to manage a cognitive resource is called the metacognition, and the improvement of this ability is effective in prevention of accidents. For the improvement of the metacognition ability, it is important not only knowledge of accidents but also the reflection of state of cognition when the accident happens. We propose to use the illusion of body image that was caused by cross modality stimulation for experience of accidents. It is thought that approach to dangerous part can be reproduced by control of body image using that illusion. We examined the method of presenting cross modality stimulation for control of body image to develop the safety-education VR contents.

A field-sequential color projection system can display color images using a single panel. However a characteristic trichromatic separation, or 'color breakup ' occurs. The viewing of images in which color breakup occurs may cause visual fatigue and mental stress. Moreover, it is expected that the state of viewing is different. In this study, the authors examine, from the standpoint of human factors, the physiological changes that can result from the viewing of images with color breakup.

Color breakup is the perceived splitting of the white portions of an image into its red, green, and blue components when the image is projected with the color sequential method and the viewer is moving his or her eyes. This study aims to evaluate how color breakup affects symptoms of visual fatigue in people with congenital nystagmus. The eyes of people with congenital nystagmus continuously oscillate leading to color breakup without pause. One in every 1 500 persons is afflicted with congenital nystagmus. Many sufferers have almost no symptoms in daily life except for a mild deterioration of visual acuity. Five subjects with congenital nystagmus were shown a 15-min portion of a movie projected with three video projectors (one liquid cyrstal display (LCD) projector and two single-chip digital light processing (DLP) projectors). They were subjectively evaluated both pre- and post-viewing with a questionnaire listing visual fatigue symptoms. One subject was tested in an additional experiment using six more projectors. Results indicated that subjects with congenital nystagmus felt severe visual fatigue after they viewed images produced by color sequential projectors. Mechanism of the cause of visual fatigue is not clear in general and in color breakup in congenital nystagmus, however, it was clear that people with nystagmus felt continuing color breakup as a flickering image. Flickering light is a major cause of visual fatigue. Color sequential projectors are best avoided in public settings, such as classrooms, lecture theaters and conference sites.

We simulated videogame scenes in simplified 3D computer graphics and evaluated the discomfort from the images by altering the simulation parameters. In the evaluation, the subjects viewed the images including oscillating motion and rotating motion with or without a fixation object. The subjective symptoms on the discomfort of image, degree of motion sickness, sense of eye movement and body movement were assessed by a 5 point rating questionnaire. Besides, the eye movements during viewing the stimuli were measured by using video camera. We found a significant relationship between the discomfort of the images and the sense of eye movement under the condition of oscillating motion. Moreover, the eye movements were reduced by adding the fixation object into the images.

眼精疲労を解消するための立体映像システムの試作を行い,その効果について生理・心理的な側面から評価を行った.

In this study, the authors developed and evaluated the virtual classroom system on cyberspace for hospitalized children. In this system, children can study and communicate with children of the outside of the hospital. The authors evaluated this system from the following viewpoints; (1) Psycho-physiological effects on children. (2) Usability of interface. (3) Spatial design of cyberspace. This paper reports the results of the experiment and discusses the validity of cyberspace in terms of education for hospitalized children.

This chapter describes 3D displays for stereoscopic images. The 3D display system will be used in broadcasting and other applications the world over in and after 2010. In this chapter, principle, technological trend and effects on human body of 3D displays are described. In addition, the activities of authors for application of 3D displays are introduced. (C) 2002 Elsevier Science B.V. All rights reserved.

In this study, we developed the system of stereoscopic images for the purpose of the welfare application to the elderly. We carried out 2 experiments to evaluate the system. On experiment 1, we confirmed the stereoscopic vision of the elderly and examined the system and the image contents. On experiment 2, we mounted 3D display on the gait-training machine and examined the system and the image contents. From the result of 2 experiments, 3 points were suggested. 1) The subjects of this system were designated the activities of daily living (ADL) as a judgment. 2) There were both affirmative and negative opinion on the image presentation. 3) It was important to select the image contents.

In this study, we carried out an experiment to compare visual load induced by images of head mount display (HMD) with different convergence of optical system. The results showed a significant aftereffect on the accommodation response time after the subjects viewed stereoscopic 3-D images on HMD. When the convergence of optical system of HMD was mismatched with the optical distance of images, the aftereffect was remarkable. The results are discussed in terms of the mismatch of accommodation and convergence in human eyes.

Manufacturing systems that employ modern technology often deprive workers of their humanity. One such example is seen in teleconferencing between remote plants. Here, it is difficult for participants to make eye-to-eye contact, a major obstacle in the communication of the participants' intentions and emotions. Indeed participants often complain that the facial expressions or emotions of the other side are difficult to perceive, that it is difficult to carry on a friendly, warm conversation, or that it is difficult to convey one's intentions to the other. They thus tend to become irritated during these conferences, and at times make erroneous judgements. In such situations, it can be said that the system users are being deprived of their humanity. This occurs because a machine or computer, when placed between two people communicating, interferes with a natural communication. What measures are there then to achieve a natural communication in such a setting, with a machine or computer between those communicating? These methods are classified here. In this study, a system for communicating 'presence' was employed to achieve a natural communication. The prototype system is called a 'dummy head for 3-D audiovisual recording'. Using this dummy head, dialogue between operators, remote control, as well as the recording of a skilled worker's use of his hands were carried out, and the results were evaluated. From these results, the authors report on how the prototype system, when placed between humans, helps to achieve a natural communication. Finally, some examples are given to show the human need for achieving a natural communication in such interface situations.

Stereoscopic 3-D images are used with a lot of virtual reality systems because of their sense of reality. At the same time, in the training that heightens levels of self control of autonomic responses with images, it is thought that reality of software is important. Therefore, the authors investigated use of 3-D images as a technical tool to heighten the reality of software. In this study, a laboratory was transformed into a relaxation room using 3-D images with fragrances and an experiment was carried out to examine the psychological effect of it. From the results of this study, the authors reported on the effects of fragrances on psychological responses when viewing 3-D images and the possibilities of producing these effects for relaxation.

Experiments were conducted to understand the basic characteristics of pointing to three-dimensional images generated by stereoscopic images. The experimental examination found that it was difficult to point to the correct position of the image and that the depth of the image was underestimated so that the object perceived by the subject was distorted. Subjects who were familiar with viewing 3-D images made less error in position and size perception than did subjects having little experience in viewing 3-D images. These results imply that the performance of 3-D pointing in stereoscopic 3-D images will improve with experience although it is difficult to perform a 3-D pointing precisely.

2眼式立体映像が, どのような情動反応を引き起こすか, また, 2眼式立体映像によってリラクセーションが可能であるかどうかを調べるために, 2つの実験を行った.実験の結果, 2眼式立体映像は, (1)心理的・生理的反応の両側面において情動反応を引き起こす, (2)その効果は, 従来の平面映像よりも, とりわけ心理反応において顕著である, (3)心理反応においては, それぞれ映像内容に対応した変化が認められた, (4)生理反応に関しては, 指尖容積脈波と表面皮膚温において, それぞれ映像内容に対応した変化が認められた, といった諸点が確認された.これらの結果は, 2眼式立体映像による自律系反応の自己制御の可能性があることを示唆している.

<p>本研究ではスマートフォンを用いた簡易型ヘッドマウントディスプレイ（HMD）による立体視（3D）コンテンツの観察において，画面サイズの変化がユーザ体験に及ぼす影響とその補正方法について，実験的な検討を行った．具体的には，簡易型HMDを用いて3Dコンテンツの呈示サイズを変化させた際のユーザ体験として，立体感，自然さ，臨場感，見やすさ，視覚負担の5項目について7件法で回答を求めた．呈示サイズと水平方向のシフトによる補正の有無を要因とした検討の結果，呈示サイズがユーザ体験に影響し，補正によりその影響が軽減されることが確認された．</p>

This paper was intended to examined whether the body sway during viewing stereoscopic three-dimensional (3D) tilted images was stable or not. Tilted 3D image was composed of directional information in which monocular disparity tilled by using a simple gradient depth map. Experiments were carried out to evaluate body sway using CG driving simulator in the five viewing conditions; left tilted 3D, right tilted 3D, forward tilted 3D, backward tilted 3D, and 2D condition. Standing twenty participants body sway was measured by using balance wii board while driving and judging on direction before trespassing the intersection. As a result, it was suggested that body sway was significantly increased to select same direction in left and right tilted image conditions.

The methods available for delivering stereoscopic (3D) display using glasses can be classified as time-multiplexing and spatial-multiplexing. With both methods, intrinsic visual artifacts result from the generation of the 3D image pair on a flat panel display device. In the case of the time-multiplexing method, an observer perceives three artifacts: flicker, the Mach-Dvorak effect, and a phantom array. These only occur under certain conditions, with flicker appearing in any conditions, the Mach-Dvorak effect during smooth pursuit eye movements (SPM), and a phantom array during saccadic eye movements (saccade). With spatial-multiplexing, the artifacts are temporal-parallax (due to the interlaced video signal), binocular rivalry, and reduced spatial resolution. These artifacts are considered one of the major impediments to the safety and comfort of 3D display users. In this study, the implications of the artifacts for the safety and comfort are evaluated by examining the psychological changes they cause through subjective symptoms of fatigue and the depth sensation. Physiological changes are also measured as objective responses based on analysis of heart and brain activation by visual artifacts. Further, to understand the characteristics of each artifact and the combined effects of the artifacts, four experimental conditions are developed and tested. The results show that perception of artifacts differs according to the visual environment and the display method. Furthermore visual fatigue and the depth sensation are influenced by the individual characteristics of each artifact. Similarly, heart rate variability and regional cerebral oxygenation changes by perception of artifacts in conditions.

New display technologies, such as 3D stereoscopic displays, provide opportunities to enhance the user experience (UK) in digital games. A widely-held belief is "the more stereo, the better experience." The purpose of this study is to examine this belief and evaluate the added value of 3D stereo to the UX in games. Stereo separation in a display was varied, and a multidimensional UX was measured using a psychological Presence-Involvement-Flow Framework(2) (PIFF2) in a between-subjects design. The PIFF2 findings were further supported by both qualitative and objective measures. Users' descriptions of the game were included as well as adverse symptoms, open-ended negative aspects of 3D stereo, basic eye physiology, objective performance metrics, and fundamental background variables. This hybrid qualitative-quantitative methodology shows that more stereo does not lead to better UX. It was shown that a moderate level of stereo separation affected the UX most by increasing the sense of presence among the users. These results deepen the previous findings in investigating the stereo effect in different media. The advantage of using multidimensional measures to evaluate UX, the added value of 3D stereo, and the practical implications of the results are further discussed.

This paper describes the making of stereoscopic 3-D movies utilizing the Metaverse. The authors focused on machinima, which is a way to make movies using PCs and video games. A tool for making stereoscopic 3-D movies in Second Life is proposed. The tool also enables running experiments with different ways of stereo shooting. The purpose of this study was to propose a novel method that supports movie creators to make stereoscopic 3-D movies easily.

Conventional stereoscopic (3D) displays using binocular parallax generate unnatural conflicts between convergence and accommodation. These conflicts can affect the observer's ability to fuse binocular images and may cause visual fatigue. In this study, time series changes in visual fatigue and depth sensation when viewing stereoscopic images with changing parallax were examined. In particular, the physiological changes, including the subjective symptoms of visual fatigue, when viewing five parallax conditions, were examined. Then a comparative analysis of the 2D and 3D conditions was performed based on the visual function. To obtain data regarding the visual function, the time series changes in the spontaneous-blinking rate before and during the viewing of 3D images were measured. The time series change results suggest that 2D and 3D images cause significantly different types of visual fatigue over the range of binocular disparity. © 2009 Taylor &amp
Francis Group, LLC.

本研究では,学習障害児の視覚的な認知特性に着目し,コンピュータ上での視覚的訓練方法を考案した.具体的には,漢字1文字を字画に分解し,再構成させる方法(分割・再構成法)である.漢字を細分割化し,視覚的に字画の形状を区別できるようにすることが,小児の書字スキルにどのように影響するかを調べた.学習障害児に,分割・再構成法による書字学習と視写法による書字学習を行い,訓練効果を比較した.その結果,短時間の訓練において,習得した漢字の構成に関する記憶は,分割・再構成法で長期間保持されることがわかった.視覚性の記憶が優位な学習障害児において,本法を用いた学習の有効性が示唆された.

In this study, the authors evaluated stereoscopic image quality for mobile devices using IBQ (Interpretation-based quality) methodology. In the experiment, paired comparisons and interviews were integrated for understanding user experience under various viewing conditions. This paper describes the results of the experiment and discusses the characteristics in the mobile stereoscopic imaging.

Digital 3D cinema has recently become popular and a number of high-quality 3D films have been produced. However, in contrast with advances in 3D display technology, it has been pointed out that there is a lack of suitable 3D content and content creators. Since 3D display methods and viewing environments vary widely, there is expectation that high-quality content will be multi-purposed. On the other hand, there is increasing interest in the bio-medical effects of image content of various types and there are moves toward international standardization, so 3D content production needs to take into consideration safety and conformity with international guidelines. The aim of the authors' research is to contribute to the production and application of 3D content that is safe and comfortable to watch by developing a scalable 3D conversion technology. In this paper, the authors focus on the process of changing the screen size, examining a conversion algorithm and its effectiveness. The authors evaluated the visual load imposed during the viewing of various 3D content converted by the prototype algorithm as compared with ideal conditions and with content expanded without conversion. Sheffe's paired comparison method was used for evaluation. To examine the effects of screen size reduction on viewers, changes in user impression and experience were elucidated using the IBQ methodology. The results of the evaluation are presented along with a discussion of the effectiveness and potential of the developed scalable 3D conversion algorithm and future research tasks.

A floating-image display produces 3-D effects using a lens system that makes an image appear to float in the air. The authors examine the effects on depth perception and asthenopia of viewing a floating image that continuously changes in size. The results of the experiments suggest that viewers perceive the floating image to be moving back and forth as the image size changes despite the Act that the image's actual position does not change. Monocular depth cues, especially changes in size, enhanced the 3-D effects of images presented on the floating-image display.

This paper presents ergonomic approaches to editing and evaluating content for 3D displays. Two systems, a nonlinear editing system and an evaluation system, were developed to improve viewing safety and comfort for 3D content observ ers and provide better usability for the creators from the viewpoint of ergonomics. © 2007 Taylor &amp
Francis Group, LLC.

This paper describes the trial development of an ergonomic evaluation system for stereoscopic video production. The purpose of the system is to quantify the parallax distribution of stereoscopic images and evaluate their viewing safety and comfort. The authors processed the images to extract the optical flow between the right and left images. The reference values for safety and comfort were obtained from two subjective evaluation and precedent studies. This paper reports the results of the experiments and the development of a prototype evaluation system.

A degree of crowdedness in public pedestrian space is obtained from sequences of greyscale images and still colour images in order to provide a route selection hint to pedestrians. Two measures are employed: amount of motion and colour entropy, and they are used selectively depending on the nature of target space. The pedestrian space is categorised into two: smooth and stagnated. The smooth space urges pedestrians to flow smoothly without pausing, while the stagnated space invites pedestrians to pause for socialising. A degree of stagnation, obtained from accumulated differentiated images, is used to distinguish these two types of space. The amount of motion and the colour entropy are compared against human's sense of crowdedness for evaluation. The experiments have shown that the amount of motion represents the smooth space's crowdedness well, while the colour entropy is suitable for evaluating the stagnated space. It has also shown tendency of significance between the degree of stagnation and the types of space.

The purpose of this study was to consider a practical application of a newly developed stereoscopic 3-D display that solves the problem of discrepancy between accommodation and convergence. The display uses dynamic optical correction to reduce the discrepancy, and can present images as if they are actually remote objects. The authors thought the display may assist in recovery from asthenopia, which is often caused when the eyes focus on a nearby object for a long time, such as in VDT (Visual Display Terminal) work. In general, recovery from asthenopia, and especially accommodative asthenopia, is achieved by focusing on distant objects. In order to verify this hypothesis, the authors performed visual acuity tests using Landolt rings before and after presenting stereoscopic 3-D images., and evaluated the degree of recovery from asthenopia. The experiment led to three main conclusions:
(1) Visual acuity rose after viewing stereoscopic 3-D images on the developed display.
(2) Recovery from asthenopia was particularly effective for the dominant eye in comparison with the other eye.
(3) Interviews with the subjects indicated that the Landolt rings were particularly clear after viewing the stereoscopic 3-D images.

We have developed a stereoscopic 3-D display system with dynamic optical correction that reduces the optical discrepancy. The contents of this system allows various camera controls in virtual space to produce different impressions. This is accomplished by means of a customized VR authoring tool attached to the system. We examined camera control patterns in VR space and effective expression techniques using this system. The results show that various camera control patterns significantly affect the Subject's impression of the images.

Stereoscopic video teaching can facilitate understanding for current minimally-invasive operative techniques. This project was created to set up a digital stereoscopic teaching environment for training of ENT residents and medical students. We recorded three ENT operative procedures (tympanoplasty, paranasal sinus operation and laser chordectomy) at the University Hospital Aachen. The material was edited stereoscopically at the Waseda University and converted into a streaming 3-D video format, which does not depend on PAL or NTSC signal standards. Video clips were evaluated by 5 ENT specialists and 11 residents in single sessions on an LCD monitor (8) and a CRT monitor (8). Emphasis was laid on depth perception, visual fatigue and time to achieve stereoscopic impression. Qualitative results were recorded on a visual analogue scale, ranging from I (excellent) to 5 (bad). The overall impression was rated 2,06 to 3,13 in the LCD group and 2,0 to 2,62 in the CRT group. The depth impression was rated 1,63 to 2,88 (LCD) and 1,63 to 2,25 (CRT). Stereoscopic video teaching was regarded as useful in ENT training by all participants. Further points for evaluation will be the quantification of depth information as well as the information gain in teaching junior colleagues.

The authors have developed a binocular-type display system that allows digital archives of cultural assets to be viewed in their actual environment. The system is designed for installation in locations where such cultural assets were originally present. The viewer sees buildings and other heritage items as they existed historically by looking through the binoculars. Images of the cultural assets are reproduced by stereoscopic 3D CG in cyberspace, and the images are superimposed on actual images in real-time. This system consists of stereoscopic CCD cameras that capture a stereo view of the landscape and LCDs for presentation to the viewer. Virtual cameras. used to render CG images from digital archives. move in synchrony with the actual cameras, so the relative position of the CG images and the landscape on which they are superimposed is always fixed. The system has manual controls for digital zoom. Furthermore, the transparency of the CG images can be altered by the viewer. As a case study for the effectiveness of this system, the authors chose the Heijyoukyou ruins in Nara, Japan. The authors evaluate the sense of immersion, stereoscopic effect, and usability of the system.

This paper describes an examination of a stereoscopic 3-D display system using a correction lens. The purpose of the system is to reduce the accommodation and convergence difference during viewing stereoscopic 3-D images by using simple technique. This correction lens is a mono-focal lens, and added to the polarized filter glasses.
In this study, the authors carried out three experiments in order to examine the appropriate utilization conditions and effects of the correction lens. In experiment 1, the refractive power of correction lens was examined under six conditions in which distances of accommodation and convergence were theoretically equal. In experiment 2, the presenting condition of stereoscopic 3-D images suitable for the correction lens was examined by measurement of refractions during viewing visual target that moved in depth direction. In experiment 3, the effectiveness of the correction lens was examined by using the utilization conditions obtained in experiment 1 and 2.
From the results of the experiments, the following conclusions were drawn.
(1) Correction lenses shift the accommodation distance.
(2) Using a correction lens with the appropriate refractive power and setting the appropriate conditions for presenting stereoscopic 3-D images reduced the difference between accommodation and convergence.
(3) The use of a correction lens affected the subjective symptoms of asthenopia.

We describe the development and evaluation of an electro-optical 3D adapter for recording stereoscopic 3D images with a standard video camcorder. The adapter uses a combination of liquid crystal shutters and a half prism to record right and left images in each field of an NTSC signal. The purpose of this study was to develop a simple and usable 3D recording system. We investigated the usability of a conventional-model 3D adapter and examined solutions to the problems we found. This adapter has the following characteristics.
(1) The 3D recordings were made using the parallel method
(2) The frame of the adapter does not obstruct light in any part of the images
(3) A correcting lens is used in close-up recordings to equalize the sizes of the right and left images
(4) The vertical disparity of each image is easy to adjust
(5) The base length can be adjusted to between 65mm and 90mm.

This paper describes the development of software for non-linear editing of stereoscopic 3-D movies. The purpose of the software is to simplify the creation of stereoscopic 3-D movies as well as reduce production costs.
The software has the following functions.
(1) Separate a field-sequential movie file into right and left movie files
(2) Display right and left movie files on time base
(3) Adjust horizontal and vertical disparities
(4) Adjust image size and rotation
(5) Correct inverted fields
(6) Measure the theoretical distance of a presented image
(7) Adjust movies created using the parallel recording method
(8) Combine right and left movie files into a field-sequential 3-D movie file
This paper reports the results of the development of the software and discusses the usefulness of the software for editing stereoscopic 3-D movies.

This paper describes a production of stereoscopic 3-D movies of a Spanish monastery for a digital archive. The authors have previously produced and presented an experimental virtual museum of Japanese Buddhist art in 1995. The purpose of this study was to produce a parallel with it, and to examine a simple method for the production.