Investigation of visual and game-playing performance under different genders,display and operation interfaces

Technological progress has led to 3D displays becoming a trend in the market, yet few studies have evaluated 3D techniques in head-mounted displays (HMD) under different topics simultaneously, such as gender and operation interfaces. This study investigated these research issues to examine the effect of gender (male, female), display interface (2D TV, 3D HMD), and operation interface (joystick, keyboard) on usability, accuracy, change of critical flicker frequency (change of CFF), Simulator Sickness Questionnaire (SSQ), and iGroup Presence Questionnaire (IPQ). Thirty participants with no NBA2K15 basketball game-playing experience were recruited in the experiment. The results showed significant effects of gender on accuracy, usability, and change of CFF, where males demonstrated higher accuracy, lower usability, and lower visual fatigue. In addition, display interface had significant effects on usability, SSQ and IPQ. The 2D TV was associated with higher usability and lower SSQ and IPQ. Furthermore, the operation interface had significant effects on accuracy, usability, change of CFF, and IPQ. The joystick led to a higher usability and IPQ but a lower change of CFF. The results provide suggestions to game players that choosing 2D TVs with joysticks generates greater usability. In addition, although they achieved a higher presence, players also had greater visual fatigue when wearing HMDs. This study concluded that males have better performance in accuracy and visual fatigue while females have better usability when playing basketball games.     

Effects of high pixel density on reading comprehension,proofreading performance,mood state,and physical discomfort

Displays with low pixel densities that were common in the 1980s and 1990s were shown to impair visual performance. Display technology, especially pixel density, has tremendously improved in recent years and new technologies allow densities of 264 ppi and beyond. Two experiments were conducted to test whether there are any measurable benefits of high pixel density displays (264 ppi) over moderate pixel density displays (132 ppi). In Experiment 1, participants performed a reading comprehension task on a display with either high or low pixel density. In Experiment 2, participants’ speed and performance in a proofreading task were compared using the same displays with high and low pixel density. There were no differences in reading comprehension and reading time (Experiment 1) as well as proofreading speed and performance (Experiment 2) between a 132 ppi and a 264 ppi display. However, subjective ratings of physical discomfort revealed significantly more complaints about headache and musculoskeletal strain in the 132 ppi condition than in the 264 ppi condition (Experiment 2). Reading comprehension, reading speed, and proofreading performance are unaffected by pixel densities above 132 ppi, but reading from high-resolution screens seems to be less exhausting at least subjectively. Thus, while large performance differences cannot be expected, displays with high pixel densities (264 ppi and above) have some advantage over displays with moderate (132 ppi or lower) pixel densities.     

Effects of display method,number of message lines,and text colour on Chinese comprehension and subjective preferences for an LED display

This study investigated the effects of display method, number of message lines and text colour on comprehension performance and subjective preferences for reading Chinese on a light‐emitting diode display. The factors and levels studied were: two text display methods (rapid serial visual presentation ‘rapid serial visual presentation (RSVP)’ and paged view scrolling), four numbers of message lines displayed at a time (one to four lines) and three text colours (amber, green and red). The RSVP method resulted in higher comprehension scores than the paged view scrolling method, and the green text produced better comprehension score than amber or red. However, the paged view scrolling received better subjective evaluation ratings than the RSVP method. A multiline display was found to be superior to a single‐line display for both comprehension scores and subjective evaluations. The results here provide useful ergonomics recommendations for choice of appropriate display method and format setting for presenting Chinese messages on light‐emitting diode displays.     

Effects of display technologies on operation performances and visual fatigue

The use of 3D stereoscopic display technology in all aspects of life has attracted considerable research attention. However, only few studies have simultaneously considered the effects of stereoscopic display technologies on visual fatigue and operating performances. This study with 36 participants (50% females; mean age = 23.17 years, SD = 3.3) analyzed the effects of display technologies, task complexity, and use time on operation performances, subjective and objective visual fatigue. Results indicated that display technology did not significantly affect the operation performances, whereas task complexity did. However, no interaction took place between them. Display technology had no significant effects on subjective visual fatigue and near-point accommodation (NPA) but affected critical fusion frequency (CFF) significantly. Use time had significant effects on both subjective and objective visual fatigue.     

Physiological effects of intermittently illuminated textual displays

Optical equipment was developed to simulate visual display terminals (VDTs) with reversed presentation (bright background and dark characters). The decay time and mean luminance were kept constant, while the oscillating frequency varied. During one experiment subjects had to read text aloud for 60min. Before and after the reading, near point distance, critical flicker fusion frequency (CFF), visual acuity, stereo depth perception, lateral heterophoria and contrast sensitivity were measured. The 30 subjects had then to report their subjective reactions on a questionnaire. The following frequencies were used: 0, 30, 60, 90, 180 Hz. In addition subjects read a normally printed text with a luminance of 75 or 150 cd/m². The main finding was that of a strong decrease of the CFF after exposure to 30 and 60 Hz. It is suggested that for reversed presentation the refresh rate should be higher than 90 Hz.     

Improving SEM Inspection Performance in Semiconductor Manufacturing Industry

Scanning electron microscope (SEM) station is one of the major quality control tasks in wafer manufacturing process. During the process of examining defects on a screen for a certain period of time, SEM inspectors frequently complain about visual fatigue problems. The purpose of the study was to evaluate the effect of wafer‐coating condition (noncoating treatment and gold‐coating treatment) and liquid crystal display (LCD) monitor size (14‐inch and 19‐inch monitor) from the aspects of objective visual fatigue measures (NPA and CFF), subjective eye fatigue rating, and inspection performance. Twelve SEM inspectors participated in this experiment. The results indicated that the treatment of gold‐coating wafer showed significant difference on reducing objective visual fatigue in NPA and CFF change. Using a 19‐inch LCD monitor also demonstrated the effect on reducing eye fatigue as well as improving inspection performance. The improvement of using a gold‐coating treatment wafer and a 19‐inch LCD monitor to reduce SEM inspectors' visual fatigue and to increase inspection performance is thus recommended. © 2012 Wiley Periodicals, Inc.     

A study on differences in human perception between a real and an AR scene viewed in an OST‐HMD

With the recent growth in the development of augmented reality (AR) technologies, it is becoming important to study human perception of AR scenes. In order to detect whether users will suffer more from visual and operator fatigue when watching virtual objects through optical see‐through head‐mounted displays (OST‐HMDs), compared with watching real objects in the real world, we propose a comparative experiment including a virtual magic cube task and a real magic cube task. The scores of the subjective questionnaires (SQ) and the values of the critical flicker frequency (CFF) were obtained from 18 participants. In our study, we use several electrooculogram (EOG) and heart rate variability (HRV) measures as objective indicators of visual and operator fatigue. Statistical analyses were performed to deal with the subjective and objective indicators in the two tasks. Our results suggest that participants were very likely to suffer more from visual and operator fatigue when watching virtual objects presented by the OST‐HMD. In addition, the present study provides hints that HRV and EOG measures could be used to explore how visual and operator fatigue are induced by AR content. Finally, three novel HRV measures are proposed to be used as potential indicators of operator fatigue.     

Spectral influence of the normal LCD,blue-shifted LCD,and OLED smartphone displays on visual fatigue: A comparative study

In this study, we investigated the influence of the light spectra of the normal LCD, blue-shifted LCD, and OLED smartphone displays on visual fatigue based on subjective and objective measurements. The illuminance of the retinal photoreceptors was calculated for the three displays to quantify the components of the light spectra. The results showed that the accumulated visual fatigue decreased for the display with lower retinal illuminances of the S-, M-, and L-cones, and ipRGCs when the luminance and CCT were the same. In addition, the display with larger retinal illuminances of the M- and L-cones induced more visual fatigue related to dry eye. Hence, a slight shift of the blue light peak toward a longer wavelength is recommended for reducing visual fatigue. Furthermore, an evaluation model of the overall visual fatigue level is proposed.     

The effect of VDU colour on visual fatigue in the fovea and periphery of the visual field

The effect of the display of a visual display unit (VDU) on visual fatigue was investigated using the critical flicker frequency (CFF) paradigm. The results indicate that fatigue, as measured by CFF, varied as the VDU colour and eccentricity changed in the visual field. It was found that blue and red, that is, both extremes of the visible spectrum, strongly caused visual fatigue in the visual field when compared to green and yellow, that is, the middle range of the visible spectrum. Furthermore, for yellow and blue, VDU signal fatigue tended to decrease as the distance from the fovea increased. whereas for red and green, it increased by up to 10° in the periphery and then tended to decrease. The results indicate that yellow and green cause less fatigue in the periphery and fovea, respectively.     

Relationship between phoria and visual fatigue in autostereoscopic 3D displays

Many people complain about visual fatigue arising from viewing three‐dimensional (3D) displays. This paper investigates relationship between visual fatigue and viewers' phoria for viewing autostereoscopic 3D displays. Visual fatigue is evaluated through subjective symptoms with a questionnaire and optometric indicators comprising fusion range as well as accommodation convergence/accommodation (AC/A) ratio to measure the variation in visual functions. A screening test is adopted to divide the subjects into two groups based on whether they suffer from phoria. Then a 2 × 2 × 2 mixed design experiment is conducted with display type, viewing stage, and visual state as factors to examine visual fatigue during viewing session. The results show that phoria subjects obtain more severe visual fatigue than normal on subjective evaluation. The normal subjects reveal a more marked difference with phoria in fusion range and AC/A ratio after viewing 3D video clip. Fusion range can significantly distinguish between the two‐dimensional (2D) and 3D condition as well as between the pre‐ and post‐viewing stages. The sensitivity and specificity of fusion range is higher than AC/A ratio with respect to viewing of 3D contents, so it is more appropriate as an optometric indicator of visual fatigue for autostereoscopic 3D displays.     

Reading from screen versus paper: there is no difference

This paper considers the effect of presentation medium on reading speed and comprehension. By directly comparing performance using screen and paper presentations, it examines the argument that it takes longer to read from a screen-based display than from paper, and that comprehension will be lower. The hypothesis is also tested that it takes longer to read light characters on a dark background compared with dark characters on a light background, and that comprehension will be lower with light-character displays. Altogether four conditions were used, with two passages read in each condition: screen with dark characters, screen with light characters, paper with dark characters, and paper with light characters. Subjects also ranked the four conditions for preference. No significant difference was found in either reading speed or comprehension between screen and paper, or between dark and light character displays. Some preference differences were found, however. Reasons for the lack of reading and comprehension differences are discussed, and it is argued that this reflects the close attention to experimental detail paid in the present experiment, which has often been missing in past studies.     

基于眼动数据的视觉疲劳检测方法研究

视觉疲劳的产生不仅会导致工作效率低下、视力降低,甚至可能导致很多意外伤害.如何简便、快速地检测视觉疲劳是亟需解决的课题.提出一种利用特殊字搜索并结合阅读任务来对视觉疲劳进行快速检测的方法.测试者需在所提供的阅读材料中通过扫视行为寻找出文内的特殊字符,同时完成相应的阅读理解任务.实验在Tobii X230眼动仪监测下完成.系统记录任务完成过程中的瞳孔直径比、兴趣域个数等眼动数据信息,并采用BP神经网络对用户的视觉疲劳状态进行判定.基于10位测试者的实验结果表明,分类精度达到了95.2%,证实了该方法的有效性.     

汉语阅读理解中词义判断题的解答研究

阅读理解任务是在给定的单篇文本上,要求计算机根据文本的内容对相应的问题作出回答。以北京语文高考阅读理解为背景,对其中的词义判断题进行了分析与研究,提出了一个基于支持度计算的解答框架,并尝试使用语言模型、点互信息与句子相似度3种方法来计算支持度。通过实验验证,3种方法在真实数据集和自动构造的数据集上均有一定成效。其中,基于点互信息的支持度计算方法在真实数据集上表现最好,获得了75%的选项正确率。     

Combined effects of working environmental conditions in VDT work

The combined effects of city noise and luminance of the computer display were evaluated from the changes in lymphocytes and mental activities of participants. Healthy male students were tested under the following four experimental conditions: (1) a calculating task on a video display terminal (VDT) with luminance of 90 cd m(-2) without city noise; (2) a calculating task on a VDT with luminance of 20 cd m(-2) without city noise; (3) a calculating task on a VDT with luminance of 90 cd m(-2) with city noise of 70 dB(A); and (4) a calculating task on a VDT with luminance of 20 cd m(-2) with city noise of 70 dB(A). A visual reaction test (VRT) was performed, and critical flicker fusion frequency (CFF), heart rate (HR), numbers of circulating white blood cells (WBCs), lymphocyte subsets and subjective symptoms of fatigue were measured (1) before; (2) just after; and (3) 30 min after each 60 min test. Subjective symptoms of fatigue significantly increased just after experiments conducted under the two noisy conditions. VRT and CFF showed significant changes in the case of the high-luminance display with noise. WBCs and neutrophils showed significant increases in the two quiet conditions. These results suggested that high luminance with noise had the most effect on subjective fatigue and mental activities.     

3‐D crosstalk and luminance uniformity from angular luminance profiles of multiview autostereoscopic 3‐D displays

Abstract— Autostereoscopic 3‐D display technologies enable a more immersive media experience by adding real depth to the visual content. However, the method used for the creation of a sensation of depth or stereo illusion contains several display design and content‐related issues that need to be carefully considered to maintain sufficient image quality. Conventionally, methods used for 3‐D image‐quality evaluations have been based on subjective testing. Optical measurements, in addition to subjective testing, can be used as an efficient tool for 3‐D display characterization. Objective characterization methods for autostereoscopic displays have been developed. How parameters affecting stereo image quality can be defined and measured, and how their effect on the stereo image quality can be evaluated have been investigated. Developed characterization methods are based on empirically gathered data. In this paper, previously presented methodology for two‐view displays is extended to cover autostereoscopic multiview displays. A distinction between displays where the change in content occurs in clear steps when the user moves in front of the display, and displays where the apparent movement of the objects is more continuous as a function of the head movement is made. Definitions for 3‐D luminance and luminance uniformity, which are equally important, as well as 3‐D crosstalk, which is the dominant factor in the evaluations of the perceived 3‐D image quality, is focused upon.     

论杂志版面设计的视觉引导和阅读体验

中国是期刊出版大国,每年有总印数30多亿册的近万种各类杂志面世,杂志已渗透到大众生活的方方面面。在人们杂志消费需求日益扩大的今天,如何更好地提升杂志版面的设计水平,更好地服务于读者并满足市场的需求,是一个极有意义的时代课题。文章以视觉引导设计和视觉阅读体验为研究视角,旨在探讨杂志版面设计的新趋势与新理念,并更深层次地思考在为读者提供丰富阅读内容的同时,杂志如何通过版面设计提供给读者更多的阅读体验和艺术跨界体验,从而进一步拓展杂志版面设计的广度和深度。     

Effect of display factors on Chinese reading times, comprehension scores and preferences

This paper presents the results of research on elemental standard reading time estimates for traditional Chinese characters on computer displays and explores the factors that may affect the time estimates. Seventy-two native Chinese readers, aged 19 to 24, were asked to read 16 simple passages and then answer four multiple-choice questions. Results indicated that the basic reading time was 213 milliseconds per character (msC^- 1) for comprehending the messages conveyed by the passages. Analysis of variance showed that font type, character size, line spacing and display polarity affected reading speed. Traditional Chinese characters of Ming style, 14-point size, double line spacing and positive polarity produced faster reading times and higher preferences than characters of Li style, 10-point size, single line spacing and negative polarity. However, only character size had a significant influence on comprehension score. Recommendations for appropriate display formats and layouts for traditional Chinese characters on computer displays based on the results of subjective preferences and objective measures are discussed.     

Effects of refresh rates of a simulated CRT display with bright characters on a dark screen

Twenty-nine subjects carried out a 3 hour reading task at a simulated CRT. In the apparatus chopper discs generated oscillating luminances of bright characters of 30, 60, 90, 180 and 0 Hz. A further control experiment was conducted with a printed text. The oscillating luminances had an approximate decay time of 4 ms (to 10% of peak luminance). The character luminance was kept constant (75 cd/m²). In the simulated CRT all characters oscillated simultaneously.Before, during and after each reading task, the following parameters were determined: Near point distance, critical flicker frequency (CFF), visual acuity, heterophorias, contrast sensitivity, eye blinking rate, and subjective symptoms of discomfort. The reading speed was continuously recorded. Furthermore the CFF at the simulated CRT was determined.The range of individual CFF at the simulated CRT was found between 40 and 56 Hz. It is concluded that most models of VDTs have today refresh rates lying in a critical range of CFF. In every condition the reading task was found to have an effect on visual functions and caused visual discomfort. Differentiated results among the six conditions were only observed for CFF and visual discomfort. The visible flicker (30 Hz) produced the strongest effects while 180 Hz, 0 Hz and the printed text were associated with relatively small effects.     

Combined effects of working environmental conditions in VDT work

The combined effects of city noise and luminance of the computer display were evaluated from the changes in lymphocytes and mental activities of participants. Healthy male students were tested under the following four experimental conditions: (1) a calculating task on a video display terminal (VDT) with luminance of 90 cd m^-2 without city noise; (2) a calculating task on a VDT with luminance of 20 cd m^-2 without city noise; (3) a calculating task on a VDT with luminance of 90 cd m^-2 with city noise of 70 dB(A); and (4) a calculating task on a VDT with luminance of 20 cd m^-2 with city noise of 70 dB(A). A visual reaction test (VRT) was performed, and critical flicker fusion frequency (CFF), heart rate (HR), numbers of circulating white blood cells (WBCs), lymphocyte subsets and subjective symptoms of fatigue were measured (1) before; (2) just after; and (3) 30 min after each 60 min test. Subjective symptoms of fatigue significantly increased just after experiments conducted under the two noisy conditions. VRT and CFF showed significant changes in the case of the highluminance display with noise. WBCs and neutrophils showed significant increases in the two quiet conditions. These results suggested that high luminance with noise had the most effect on subjective fatigue and mental activities.     

Effects of electronic‐book display and inclination on users' comprehension under various ambient illuminance conditions

Abstract— This study used several electronic‐book (e‐book) displays (a conventional LCD under transmissive mode, a conventional LCD under reflective mode, a Ch‐LC display, and an e‐ink display) to investigate the effect of e‐book inclination (105° and 135°) and ambient illuminance (200, 800, 1500, and 2200 lux) on the comprehension of subjects. Results indicate that the ambient illuminance does not significantly affect the comprehension of subjects. However, their comprehension differed significantly when using different e‐book displays. In addition, the interaction between illuminance and e‐book display had a significant effect on their comprehension. When the ambient illuminance was set at 800, 1500, and 2200 lux, the subjects' comprehension for reading different e‐book displays did not show a significant difference. When the ambient illuminance was set at 200 lux, however, their comprehension for reading a Ch‐LC display, an e‐ink display, and a conventional LCD under transmissive mode were better than their comprehension of reading a conventional LCD under reflective mode. Regarding the inclination for using e‐books, the subjects' comprehension was better under 105° than that under 135°.