<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 paper describes a study that focuses on disparity changes in emotional scenes of stereoscopic (3D) images, in which an examination of the effects on pleasant and arousal was carried out by adding binocular disparity to 2D images that evoke specific emotions, and applying disparity modification based on the disparity analysis of famous 3D movies.
From the results of the experiment, for pleasant, a significant difference was found only for the main effect of the emotions. On the other hand, for arousal, there was a trend of increasing the evaluation values in the order 2D condition, 3D condition and 3D condition applied the disparity modification for happiness, surprise, and fear. This suggests the possibility that binocular disparity and the modification affect arousal.

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.

In this study, a basic examination on psycho-physiological effects by display systems of stereoscopic 3D images (3D) was carried out. Time-multiplexing and spatial-multiplexing systems were focused as major 3D display systems for consumer use. Characteristic artifacts of each system were extracted, and their psycho-physiological effects were evaluated.Concretely, phantom array, pseudo parallax and flicker from time-multiplexing system, and binocular-rivalry, pseudo parallax and reduction of resolution from spatial-multiplexing system were defined as characteristic artifacts and represented by simple visual stimuli for experiments. From the results of the experiments, inductions of the artifacts were confirmed, and the psycho-physiological responses of the participants were changed by the intensity or combination of the artifacts. In addition, individual difference of the artifacts in the psycho-physiological effects and the interactions, and possibilities to reduce the effects by presentation methods were suggested.

The use of salivary cortisol is an active research area receiving much interest with implications for basic and clinical purposes. In this study, changes in salivary cortisol following cognitive-behavioral therapy (CBT) were investigated in patients with panic disorder. Nine patients with panic disorder with agoraphobia participated in a six-session CBT program. Panic disorder severity, avoidance behaviors, anxiety, depressive symptoms, and general self efficacy were evaluated before and after the program. Moreover, saliva samples for cortisol assessment were obtained 6 times (awakening, 15 and 30 minutes after awakening, 3 and 8 hours after awakening, and bedtime) before and after the program. Three cortisol parameters, the diurnal slope (changes in cortisol from awakening to bedtime), awakening response (the increase in cortisol secretion over the first 30 minutes after awakening), and total cortisol output over the day (cortisol area under the curve for the 8 hour periods after awakening) were computed for each day. Patients showed improvements in panic disorder severity, avoidance behaviors, and general self efficacy ratings following the CBT program. Analyses of cortisol parameters showed that the diurnal slope increased after completing the program (t[7]=2.51, p<0.05). Correlation analyses also demonstrated that an improvement in the panic disorder severity rating was associated with decreased total cortisol output (r_s=0.71, p<0.05) and that decreased levels of anxiety were associated with decreased total cortisol output (r_s=0.78, p<0.05) and awakening response (r_s=0.81, p<0.05). These results suggest that salivary cortisol could be a useful tool for evaluating the effects of CBT programs. It is likely that the use of salivary cortisol will continue to expand, thus being applied in a variety of clinical settings.

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.

Since 3D display methods and viewing environments vary widely, high-quality content is expected to become multi-purpose. Meanwhile, there is increasing interest in the bio-medical effects of various types of image content and there are moves toward international standardization, so safety and comfort need to be considered in 3D content production. The aim of the authors' research is to contribute to the production and application of 3D content that is safe and comfortable. In this paper, the authors focus on the process of changing the screen size, examining a scalable 3D conversion algorithm and evaluating its effectiveness. The authors evaluated the visual load imposed during the viewing of various 3D contents converted by the prototype algorithm by comparing them with ideal conditions and with content expanded without conversion. To examine the effects of screen size reduction on viewers, changes in user impression and experience were elucidated using an evaluation grid method.

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.

The authors have developed a literacy learning system that presents hiragana characters on a stereoscopic 3D display. Strokes of hiragana character were arranged in depth direction on this learning system. The authors used a Multi-layered Display (MLD) for representation of depth direction. The MLD does not cause any discrepancy between accommodation and convergence of human visual function. The system was evaluated by children with developmental dyslexia. Three hiragana characters written before and after using this system were compared. The results suggest that stereoscopic vision can help those with developmental dyslexia understand how to write hiragana characters.

This paper describes effects of stereoscopic 3-D images with dynamic optical correction on asthenopia recovery. The authors have developed a stereoscopic 3-D display with dynamic optical correction. In this study, the authors carried out two experiments in order to examine the effectiveness of asthenopia recovery using the 3-D display. In experiment 1, visual acuity tests and asthenopic subjective symptoms were performed before and after viewing stereoscopic 3-D images on the display, and the degree of asthenopia recovery was evaluated. In experiment 2, the subjects were persons whose work basically involved using VDTs all day long. Experiments in asthenopia recovery were carried out in the evening. Measurements were also taken in the morning in order to determine normal daytime vision. Additionally, a refraction feedback function for presenting stereoscopic 3-D images on the display was used for making the viewer's distance vision more effective. The results of the experiments suggested that asthenopia recovery using stereoscopic 3-D images with optical correction was more effective than 2-D images. It was suggested that although these asthenopia recoveries might be temporary, viewing stereoscopic 3-D images with optical correction created refreshing sensations such as felt upon awakening.

This paper provides a report of a research project on virtual revival of the Citadel of Bam, a UNESCO world heritage site in danger that was destroyed in an earthquake in 2003. The simulation of damaged buildings that lies along the primary axes of the citadel and 3-D reconstitution using state-of-the-art 3DCG tools are presented. The key approach to 3-D modeling of the destroyed buildings is complementary usage of heterogeneous data such as 2-D maps, photos, cartography maps, and sketches in collaboration between different teams. As the basic 2-D maps had error, analytic and comparative research is conducted on diverse data resources to create a knowledge-base for the 3DCG restoration of the site. The process of modeling is completed with regard to the complicated and curved mud brick buildings with traditional architectural details. For this purpose proper functions of the tools is selected and in some cases different tools are used. The modeling is done by linking the component with their semantic by a metadata-based layer naming process. The tasks of evaluating the historical, architectural, and technical details of the 3-D buildings are done in parallel with the modeling by a team of CG and architecture experts in order to increase the precision of the 3DCG reconstitution so that it can be used as a reference for the physical restoration. The first trial version of virtual reality demonstration of the main axes of the Citadel of Bam is described. The paper concludes with proposals to enhance the process of simulation and also to open the restricted views of the virtual reconstitution on Internet.

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.

In this paper, presence display systems utilizing human body information that promoted by the authors are described as followings; (1) a stereoscopic display using dynamic optical correction, (2) a body-image display using an illusion.

A field-sequential color projection system can display color images using a single panel. However, it suffers from a characteristic trichromatic separation known as "color breakup". The viewing of images exhibiting color breakup may cause visual fatigue and mental stress. In this study, the authors examine, from the standpoint of human factors, the objective and subjective symptoms 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.

In this study, the authors examined the psycho-physiological effects related to asthenopia and caused by viewing image contents using a monocular head mount display (HMD). In the psychological responses, although a significant increase in asthenopic subjective symptoms was found after 30 minutes' viewing, recovery to near pre-viewing conditions was possible by taking 15 minutes rest. On the other hand, in terms of physiological responses, few changes of the refraction of the eye after viewing were found.

The authors developed the stereoscopic 3-D display system for reduction of asthenopia, and evaluated it from the view point of psycho-physiological responses.

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.

Two experiments to examine the effects of the stereoscopic images on the emotional states and on relaxation confirmed the following : <BR>1) Stereoscopic images have both psychological and physiological effects.<BR>2) Psychological effects are more notable than are those of 2D images.<BR>3) Psychological changes depend on images contents (activation and relaxation).<BR>4) Physiological changes (volume pulse wave and skin surface temperature) also depend on images contents.<BR>These results suggest that stereoscopic images cause emotional changes (activation and relaxation) and that there is a possibility of the selfcontrol of autonomic nerves by stereoscopic images.

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.

In video abstraction, viewer's emotional reactions to original video play an important role because people often choose what to watch based on the emotional context. We have devised a method for incorporating viewer's perceived impressions in video abstraction. The impression level is measured by the degree of arousal, based on two measures of heart activity: deceleration of heart rate and activation of the higher frequency component of the heart rate variability. For an evaluation of our method, we performed two sets of experiments comparing the abstracts generated by our method against subjective selections. Three short videos with different arousal levels (two arousing and one calm) were used. In Experiment 1, shot matching between two abstracts was examined: the arousing videos showed a 50% match, while the calm one showed a 30% match. In Experiment 2, the abstracts were displayed to the subjects, which they evaluated subjectively: our method generated good results in the arousing/pleasant video.

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.

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.

A field-sequential color projection system displays color images using a single panel and a color filter wheel. The wheel spins very rapidly, and creates a sequence of red, green, blue, and white images that combine to create a single full-color image. Although the use of a single panel can reduce both projector size and costs, the field-sequential color projection mechanism causes the observer to perceive trichromatic separation during times of rapid eye movement. This phenomenon is called "color breakup". We examine the characteristics of saccadic eye movement, which result from viewing images containing color breakup. We describe two experiments that were conducted to examine the effects of color breakup as manifested through the ergonomic indices of eye movement and the subjective symptoms of asthenopia.

The experimental production of an ergonomic evaluation system for stereoscopic 3-D images is described. The purpose of the system is to quantify the depth sensation of 3-D images and to evaluate them. Image processing was applied to compute the optical flow between right and left videos. The functionality of the system was examined by referring to previous reports and by conducting two experiments. The results of the improvement and the validity of the system in terms of 3-D image creation are reported.

We developed a prototype system to reduce asthenopia by using stereoscopic 3-D images that moved in depth direction, and evaluated the effects of the system. Accommodative step response time, profiles of mood states and refractions were measured as indexes for examining the subject's visual fatigue. In young subjects, the accommodative relaxation time tended to be shortened by watching the images. This tendency indicates that the ciliary muscle quickly relaxed. In contrast, we observed an increase of accommodation in some aged subjects while they viewed the images. These results suggest that the work of the ciliary muscle is activated by observing the images. Our results suggest the possibility that viewing stereoscopic 3-D images can reduce asthenopia.

We developed software for the non-linear editing of stereoscopic 3-D movies. This software has functions unique to stereoscopic 3-D movies and works on a personal computer. Editing is much simpler with this software than it is with conventional systems that require four synchronized video tape recorders. At the same time, the software makes possible the post-recording adjustment of field-sequential 3-D movies, a difficult task for conventional editing systems. In addition, the results of the usability test confirmed the software's ease of use and enhancement of editing tasks.