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Japan has become a more aged society and there are more drivers, 65 years of age and above. Cars represent an important mode of transportation for the elderly; however, in recent years, the number of traffic accidents caused by elderly drivers has been on the rise, and this has become a social issue. Thus, for the elderly drivers to encourage them to improve their driving, we study a driver agent system which consists of smartphone, communication robot and cloud service and provides the driving support by attention awakening and the feedback support based on driving behavior evaluation. In this paper, we presented a summary of the proposed agent and reported on a set of preliminary experiments using our agent in an actual car environment. From the analysis of subjective evaluations and fixation points during driving, the results revealed the possibility that the drivers accept the agent and supports from the agent during driving and that the agent in an actual car environment did not distract the driver.

Humans obtain information from their five senses, which include vision. In recent decades, numerous displays have been developed as a result of technological advancements, and such apparatuses can be used in daily life. The development of evaluation indicators for gaze data is a very important research topic in the hygiene field. In this chapter, we outline the types of eye movements, such as the saccade, smooth pursuit eye movement, vergence eye movement, optokinetic nystagmus, vestibulo-ocular reflex, and rotational eye movement. Thereafter, we introduce several methods for measuring eye movements, including the magnetic search coil method, pupil center corneal reflection method, limbus tracking meth-od, image analysis method, and electrooculography. Based on the eye movements measured by noncontact devices, indices are developed to evaluate the severity of visually induced motion sickness.

The viewers of three-dimensional (3D) movies often complain of blurring and bleeding. They sometimes experience visually induced motion sickness (VIMS). In this chapter, the effect of VIMS on body sway was examined using stabilograms. We measured the sway in the center of gravity before and during the exposure to images projected on a head-mounted display (HMD). Employing Double-Wayland algorithm, we measured the degree of determinism in the dynamics of the sway in the center of gravity with respect to viewing 3D movies on HMD. As a result, the dynamics of the sway during and before the exposure was considered to be stochastic. Thus, exposure to 3D movies would not change the dynamics to a deterministic one.

It is said that the most cause of traffic accidents is the lack of confirming the safety. Visual information from both eyes is one of the important factors for safe driving. In this paper, we collect eye-gaze data of drivers who watch a driving video, and try to develop a model of their eye movements to identify factors to enhance their safety. For the purpose of modeling, we adopted a recurrent neural network and Long Short-Term Memory (LSTM) to the collected eye-gaze data because the LSTM is able to deal with a time-series data such as the eye-gaze data. Moreover, we performed an experiment to evaluate the identification accuracy of drivers. The results indicated that the driver’s intention and habit can be approximated partially by the trained network, but it was insufficient to identify a personal driver for practical use.

The technology provides an enhanced visual experience with realistic scene portrayal, but is known to cause motion sickness when stereoscopic video clips of rotating or blurred images are viewed. Viewers complain of symptoms such as eye fatigue, nausea, and dizziness. The underlying cause of these symptoms has not been identified; therefore, an investigation to determine the mechanism for the motion sickness is necessary. Compared to the baseline test, the concentration of oxygenated hemoglobin in the occipital lobe increased significantly during a viewing for both background cases. The result is consistent with both visual recognition methods. Furthermore, for both background cases, the concentration in the upper occipital lobe significantly increased during peripheral viewing versus visual pursuit. Peripheral viewing might enhance the activity in the dorsal stream, which could serve as an indication to the mechanism causing 3D sickness.

液晶ディスプレイによる動画表示は特有の「ぼやけ」や「にじみ」を伴うという欠点があったが, OCB液晶技術によって開発されたディスプレイはこの問題を解消した. そこで, OCB液晶ディスプレイと従来からの液晶ディスプレイについて, 高齢者から若年者までの幅広い年齢層を対象として, 動画を注視している際の重心動揺の測定を行った. 被験者は, 20歳から73歳の正常裸眼視力または正常な矯正視力を有するとともに, 平衡機能に既往症のない55名を対象とした. OCB液晶ディスプレイと従来からの液晶ディスプレイには, 横方向にスクロールする地図を表示した. 重心動揺の測定結果は, 定量化指標を用いて比較検討を行った. その結果, OCBディスプレイと従来型ディスプレイの間に差が認められ, OCBディスプレイ注視時は重心の不安定さが改善されたことが示された. この傾向は, 若年層で著しく, 中年層と高齢者では従来型ディスプレイ注視時とOCBディスプレイ注視時との差異は有意ではなかった.

In the present study, we examined the visual accommodation of subjects who were gazing fixedly at stereoscopic images on two different displays: a cathode ray tube (CRT) with the subjects wearing liquid crystal shutter glasses and a liquid crystal display (LCD) with the subjects not wearing liquid crystal shutter glasses. In Experiment 1, we measured accommodation in subjects viewing a moving stereoscopic image. In Experiment 2, we measured accommodation in subjects viewing moving stereoscopic images on an LCD and a CRT. In Experiment 3, we measured accommodation in subjects viewing a stereoscopic image moving from far to near on an LCD. In Experiment 4, we measured of accommodation in subjects viewing moving stereoscopic images (stereoscopic display mode) and non-stereoscopic images (2-D mode) on an LCD. The results suggested, the ciliary muscle is repeatedly strained and relaxed while the subject views the moving target. In the present study, the subjects’ accommodative amplitude was changed when the target moved from the near to far point, and vice versa. Ke yw ords: Accommodation, Binocular Vision, Stereoscopic Image and Visual Display

Visually induced motion sickness (VIMS) is caused by sensory conflict, the disagreement between vergence and visual accommodation while observing stereoscopic images. VIMS can be measured by psychological and physiological methods. We propose a mathematical methodology to measure the effect of three-dimensional (3D) images on the equilibrium function. In this study, body sway in the resting state is compared with that during exposure to 3D video clips on a liquid crystal display (LCD) and on a head mounted display (HMD). In addition, the Simulator Sickness Questionnaire (SSQ) was completed immediately afterward. Based on the statistical analysis of the SSQ subscores and each index for stabilograms, we succeeded in determining the quantity of the VIMS during exposure to the stereoscopic images. Moreover, we discuss the metamorphism in the potential functions to control the standing posture during the exposure to stereoscopic video clips.

It is physiologically known that the vestibular system and the autonomic nervous system interact with each other. The motion sickness can affect both these systems, and severity of the motion sickness is expected to be measured by dysfunction of the equilibrium system. We have proposed a new index, sparse density (SPD), of stationary stabilograms for detecting the metamorphism in the (temporally averaged) potential function of stochastic differential equations, which occurs when a human attempts to maintain an upright posture. It is known that a mathematical model of the body sway can be developed by a stochastic process. The authors have succeeded in finding the nonlinearity in the potential function. Subjects in a standing position were stimulated by a movie scrolling from left to right on a liquid crystal display (LCD) in measurement 1 and a stereoscopic video clip on an LCD in measurement 2. As a result, the dynamics of the body sway in the presence of the stimulus as well as in its absence were considered to be stochastic. The metamorphism in the potential function during exposure to blurred images and a stereoscopic video clip could be detected by using the SPD.

We propose a new index, sparse density (SPD), of stationary stabilograms for detecting the metamorphism in the (temporally averaged) potential function of stochastic differential equations, which occurs when a human attempts to maintain an upright posture. It is known that a mathematical model of the body sway can be developed by a stochastic process. The authors have succeeded in finding the nonlinearity in the potential function. In this study, subjects in a standing position were stimulated by three-dimensional (3-D) movies on an head-mounted display (HMD). We also measured the degree of determinism in the dynamics of the sway of the center of gravity of the subjects. The Double-Wayland algorithm was used as a novel method. As a result, the dynamics of the body sway in the presence of the stimulus as well as in its absence were considered to be stochastic. The metamorphism in the potential function during exposure to the conventional 3-D images could be detected by using the SPD.

It has been reported that even users of virtual environments and entertainment systems experience motion sickness. This visually induced motion sickness (VIMS) is known to be caused by sensory conflict, for instance, the disagreement between vergence and visual accommodation while viewing stereoscopic images. The simulator sickness questionnaire is a well-known tool that is used herein for verifying the occurrence of VIMS. We used the SSQ and also quantitatively measured head acceleration and sway of the center of gravity of the human body before and during the exposure to stereoscopic images on a head-mounted display. During the measurement, the subjects were instructed to maintain the Romberg posture for the first 60 s and a wide stance (with the midlines of heels 20 cm apart) for the next 60 s. We proposed a method to obtain stochastic differential equations (SDEs) as a mathematical model of the body sway on the basis of the stabilogram. While there are several minimal points of time-averaged potential function in the SDEs, the exposure decreases the gradient of the potential function. We have succeeded in estimating the decrease in the gradient of the potential function by using an index called sparse density.

In order to evaluate display devices, a geostationary image and the character were generally used in previous studies. We have proposed a new method for comparing the standing posture when a subject views a liquid crystal display (LCD) displaying a movie scrolling from the left to the right. In this study, we mathematically measured the degree of determinism in the dynamics of the sway of center-of-gravity. The Double-Wayland algorithm was used as a novel method. As a result, the dynamics of the sway when subjects viewed the movie as well that of the sway in the resting state was considered to be stochastic. The moving map task would not change it into a deterministic one.

Visually induced motion sickness (VIMS) is known to be caused by sensory conflict, which is the disagreement between vergence and visual accommodation while observing stereoscopic images. The simulator sickness questionnaire (SSQ) is a well-known method that is used herein for verifying the occurrence of VIMS. We quantitatively measure the sway of the centre of gravity of the human body before and during exposure to several images. During the measurement, subjects are instructed to maintain the Romberg posture for the first 60 s and a wide stance (midlines of the heels 20 cm apart) for the next 60 s. The stereoscopic images decrease the gradient of the potential function involved in the stochastic differential equations as a mathematical model of the body sway. We have succeeded in estimating the decrease in the gradient by using an index called sparse density.

In the present study, we examined the visual accommodation of subjects who were gazing fixedly at 3D images from two different displays: a cathode ray tube (CRT) while wearing special glasses and a liquid crystal display (LCD) while not wearing special glasses. The subjects in this experiment were two healthy people aged 22 and 39 years, all with normal vision. The instrument objectively measured visual accommodative changes of the right eye in both binocular and natural viewing conditions. The results suggested that it was easy and comfortable to focus on both the LCD and CRT. When the subjects viewed the progressively receding target, their accommodation was about 0.8 D at the presumed furthest points, a level at which the ciliary muscle is relaxed. The accommodative power differed by about 1.5 D from the near to far point. Thus, the ciliary muscle is repeatedly strained and relaxed while the subject views the moving target.

The viewers of three-dimensional (3D) movies often complain of blurring and bleeding. They sometimes experience visually induced motion sickness (VIMS). In this study, the effect of VIMS on body sway was examined using stabilograms. We measured the sway in the center of gravity before and during the exposure to images projected on a head-mounted display (HMD). While viewing, the subjects were instructed to remain in the Romberg posture for the first 60 seconds and maintain a wide stance (midline of the heels, 20 cm apart) for the next 60 seconds. Employing Double-Wayland algorithm, we measured the degree of determinism in the dynamics of the sway in the center of gravity with respect to viewing 3D movies on HMD. As a result, the dynamics of the sway during and before the exposure was considered to be stochastic. Thus, exposure to 3D movies would not change the dynamics to a deterministic one.

The purpose of this study was to clarify the effect on visual function of gazing at stereoscopic images on a head mounted display (HMD). We measured visual accommodation during stereoscopic viewing while using a HMD by using our original instrument of measurement. The presented image was shown 3-dimensionally on an HMD set up at a visual distance of 3 cm. A spherical object moved back and forth toward and away from the observer in a 10 sec cycle. While the subjects were gazing at the 3D image with both eyes, the lens accommodation in the right eye was measured and recorded. Accommodation to the virtual objects was shown during the viewing of stereoscopic images of 3D computer graphics, but was not shown when the images were displayed without appropriate binocular parallax. It is suggested that stereoscopic moving images on HMD induced the visual accommodation by the expansion and contraction of the ciliary muscle, which is synchronizing with convergence.

Often, people travelling in ships, trains, aircraft, and cars tend to experience motion sickness. It has been reported that even users of virtual environments and entertainment systems experience motion sickness. This visually induced motion sickness (VIMS) is known to be caused by sensory conflict, which is the disagreement between vergence and visual accommodation while observing stereoscopic images. VIMS can be measured by psychological and physiological methods. The simulator sickness questionnaire (SSQ) is a well-known method that is used herein for verifying the occurrence of VIMS. We also quantitatively measure the sway of the centre of gravity of the human body before and during exposure to several types of movies. During the measurement, subjects are instructed to maintain the Romberg posture for the first 60 s and a wide stance (with midlines of the heels 20 cm apart) for the next 60 s. The centre of gravity is projected on a plane that is parallel to the ground. The body sway is recorded as a stabilogram on the plane. According to previous research, a stochastic process is regarded as a mathematical model that generates stabilograms. We propose a method to obtain stochastic differential equations (SDEs) as a mathematical model of the body sway on the basis of the stabilogram. While there are several minimal points of the temporally averaged potential function involved in the SDEs, the stereoscopic images decrease the gradient of the potential function. We have succeeded in estimating the decrease in the gradient of the potential function by using an index called sparse density.

An experiment was conducted on the ease with which a car navigation system could be read by elderly, middle-aged and young people. 127 subjects (19-76 years of age) evaluated ease of reading of the displayed characters. The experiment evaluated characters displayed on a liquid crystal display (LCD) similar to those used in car navigation systems, and evaluated readability in 9 stages. Five character sizes for traffic terms and two languages (Japanese and English) were used in the experiment. The experiment was conducted with the LCD in 2 positions: directly in front of the subject and diagonal to the left (about 30 degrees). The results showed that the directly frontward position was significantly more readable than the position of diagonal to the left.

The purpose of this study was to examine the relationships between the visibility of mobile phone displays and aging effects on subjects' visual functions, based on measurements of vision, including near visual acuity and cataract cloudiness. In the relation between Character size, CC, and NVA, visibility was lower with smaller character size "S". In the relation between Contrast, CC, and NVA, the organoleptic evaluations showed significant differences in contrast. The subjects' attached a high value to the negative display mode, especially when the subject's CC was more than 200. Such considerations are particularly important for elderly users who have marked deterioration of visual function.