Exploring and modeling unimanual object manipulation on multi-touch displays

Touch-sensitive devices are becoming increasingly wide-spread, and consequently gestural interfaces have become familiar to the public. Despite the fact that many gestures require frequently dragging, pinching, spreading, and rotating the finger-tips, there currently does not exist a human performance model describing this interaction. In this paper, a novel user performance model is derived for virtual object manipulation on touch-sensitive displays, which involves simultaneous translation, rotation, and scaling of the object. Two controlled experiments with dual-finger unimanual manipulations were conducted to validate the new model. The results indicate that the model fits the experimental data well (with R² and R values above 0.9), and performs the best among several alternative models. Moreover, based on the analysis of the empirical data, the simultaneity nature of manipulation in the task is explored and several design implications are provided.     

Effects of 3D displays: A comparison between shuttered and polarized displays

The current study investigates the effects of 3D displays (shuttered display vs. polarized display). People experienced superior fidelity and brightness when they watched 2D still images on a shuttered display, rather than on a polarized display. Conversely, people experienced greater brightness when they watched 3D still images on a polarized display, rather than on a shuttered display. Second, people were able to read a smaller font or characters on a shuttered display than on a polarized display. Third, people noticed flickering on a shuttered display when they watched 3D images. Fourth, people experienced greater brightness when they watched 3D moving images on a shuttered display, rather than on a shuttered display. The perceived brightness of the screen positively correlated with enjoyment, content satisfaction, and 3DTV satisfaction when the viewers watched a 3D movie. The flickering, on the other hand, has a negative correlation with enjoyment and 3DTV satisfaction.     

A comparison of hierarchically paged and scrolling displays for fault finding

The selection of test points when fault finding with a hierarchically paged display is more efficient than when using a scrolling display. However, this difference is not found with more able subjects. An unexpected finding is that both displays seem to facilitate more consistent performance than that obtained when the operator's view of the system is unrestricted. The effect of restricting system information by a ‘window’, as both types of display do, is discussed in terms of strategies operators may adopt in consequence, in particular strategies to cope with memory load.     

Analytical model for three-dimensional light-field displays based on voxel construction

Three-dimensional light-field displays (3D-LFDs) can provide viewers with glass-free 3D images. The display effect of reconstructed 3D images is closely related to the number of 3D object points that the 3D display system can construct, which can be regarded as the information quantity of the 3D-LFDs. However, the information quantity presented by a 3D-LFD is limited by fixed hardware parameters such as display panels and optical components. It is difficult to present an ideal 3D visual experience with the increase in display depth. In this paper, an analytical model based on voxel construction for 3D-LFDs is proposed, which can estimate the information quantity that a 3D-LFD can reproduce. The variation regularity of information quantity with display depth is analyzed and the influence of hardware parameters on display effect is discussed. With the proposed strategies, the display effect can be improved in a targeted manner without blurring and aliasing by adjusting the hardware parameters in display systems and matching the information quantity at different display depths.     

A new modeling interface for the pen-input displays

Sketch interactions based on interpreting multiple pen markings into a 3D shape is easy to design but not to use. First of all, it is difficult for the user to memorize a complete set of pen markings for a certain 3D shape. Secondly, the system will be waiting for the user to complete the sequence of the pen markings, often causing a certain mode error. To address these problems, we present a novel, interaction framework, suitable for interpretations based on single-stroke marking on pen-input display; within this framework 3D shape modeling operations are designed to create appropriate communication protocols.     

Comparative studies of single-polarizer reflective liquid-crystal displays

Abstract— The electro-optic effects and viewing-angle characteristics of some recently developed single-polarizer reflective liquid-crystal displays are compared under the same material parameters. The mixed-mode twisted-nematic cells and biaxial film-compensated thin homogeneous cells are promising for both direct-view and projection displays employing crossed polarizers. How to improve contrast ratio for the parallel-polarizer displays remains a technical challenge.     

Advances towards high‐resolution pack‐and‐go displays: A survey

Abstract— Tiled displays provide high resolution and large scale simultaneously. Projectors can project on any available surface. Thus, it is possible to create a large high‐resolution display by simply tiling multiple projectors on any available regular surface. The tremendous advancement in projection technology has made projectors portable and affordable. One can envision displays made of multiple such projectors that can be packed in one's car trunk, carried from one location to another, deployed at each location easily to create a seamless high‐resolution display, and, finally, dismantled in minutes to be taken to the next location — essentially a pack‐and‐go display. Several challenges must be overcome in order to realize such pack‐and‐go displays. These include allowing for imperfect uncalibrated devices, uneven non‐diffused display surfaces, and a layman user via complete automation in deployment that requires no user invention. We described the advances we have made in addressing these challenges for the most common case of planar display surfaces. First, we present a technique to allow imperfect projectors. Next, we present a technique to allow a photometrically uncalibrated camera. Finally, we present a novel distributed architecture that renders critical display capabilities such as self‐calibration, scalability, and reconfigurability without any user intervention. These advances are important milestones towards the development of easy‐to‐use multi‐projector displays that can be deployed anywhere and by anyone.     

Measurement of image quality for large-screen displays based on audience viewing: Overview of standardization and preliminary study on laser projection displays and LED displays

The large screens used in stadiums, shopping malls, and movie theaters typically have multiple viewers looking at them simultaneously. The quantification of these displays' image quality would require more considerations of measurements at different locations to satisfy the multiviewing condition. In this paper, we describe the practical implementation method involved in the current standardization activities. Additionally, a vantage point measurement method is studied. In the actual use case scenarios, the vantage point method is more appropriate. This method mimics the viewing behavior of audiences. The displays we measured were laser projection and LED. The method shows validity in both displays. Using the vantage point method, the experimental data show that the existing large displays may have very prominent differences in luminance and chromaticity at different viewing locations.     

Measurement of light incident on mobile displays in various environments

Abstract— By using a single‐lens digital camera with an attached 180° fisheye lens, the incident light at the surface of a mobile display in 112 different environments, including outdoor and indoor environments and inside an automobile, were measured. The data were analyzed for some typical environments in which mobile displays are used. The results of this research can be used in the design of reflective and transflective LCDs, making maximum use of ambient light.     

Conformable displays based on polymer‐dispersed liquid‐crystal materials on flexible substrates

Abstract— We have developed a process that enables one to conform polymer‐dispersed liquid‐crystal (PDLC) displays into a particular shape indefinitely. Planar PDLC displays are first fabricated between indium tin oxide (ITO) coated polyethylene terephthalate (PET) substrates. This fully functional display can then be conformed to a particular shape by heating above the glass‐transition temperature of PET and then allowing it to cool down to room temperature. The display retains its shape and is fully functional after processing. We have created spiral‐and wave‐like samples and have demonstrated their operation after the conformal process. The stress is relieved in the substrate by conforming. Temperature effects on polymer substrates were investigated for two types of polymer films (PET/ITO substrates and a conducting polymer PEDOT:PSS/PET substrate) to analyze the effects of temperature on the resistance and mechanics of the films under an applied uniaxial strain. We have found a decrease in contrast of the PDLC after conforming, but surprisingly, a reduced threshold voltage and reduced hysterisis occurs.     

Human factors of 3‐D displays

Abstract— This paper provides a selected review of a number of important perceptual and human‐factors issues that arise when 3‐D displays are designed and used. This review and analysis draws heavily from the basic vision literature in order to help provide insight for future design solutions for 3‐D displays. Issues discussed include (1) the basics of human stereopsis, (2) interocular crosstalk, (3) oculomotor responding and distance scaling of binocular disparity information, (4) accommodative‐vergence mismatch, and (5) stereoanomly. The paper concludes with a presentation of several recommendations for the design of 3‐D displays.     

Optical performance characterization of flexible mobile displays

The high interest in the display industry to produce curved or flexible displays for mobile, wearable, and television markets has raised concerns on the performance of displays in their bent state. Flexible display technologies have been developed for this purpose, but their optical characteristics have not been previously reported at various degrees of curvature. The measurement of flexible displays is possible only with special measurement arrangements using common display characterization devices. A conoscope with a working distance of 15 mm was used to demonstrate the curvature dependence of luminance, viewing angle, and color coordinates of the white point of a flexible active‐matrix organic light‐emitting display. The results show that the effect of curvature on the optical characteristics of the display is most evident at the smallest measured bending radii of +/?50 mm and that the effects are most visible when viewing the bent ends of the display, from the central normal vantage point, with uniform curvature along the display.     

Comparison of reflective PNLCDs and reflective single‐polarizer Heilmeier guest‐host displays

In this paper, the applicability of a zero‐polarizer reflective display (PNLC) and a single‐polarizer reflective display (Heilmeier guest host) for direct‐view applications is analyzed. A measurement set‐up is designed to analyze the applicability of all types of reflective displays. Simulation of the different types of illumination caused by the environmental light is essential for this set‐up. The measurements indicate that the contrast ratio and reflectance greatly depend on the type of illumination. It is demonstrated that the worst‐case illumination for one display technology may be the best‐case illumination for another one and vice versa.     

A comparative evaluation of in-vehicle side view displays layouts in critical lane changing situation

Abstract

This study conducted a driving simulator experiment to comparatively evaluate three in-vehicle side view displays layouts for camera monitor systems (CMS) and the traditional side view mirror arrangement. The three layouts placed two electronic side view displays near the traditional mirrors positions, on the dashboard at each side of the steering wheel and on the centre fascia with the two displays joined side-by-side, respectively. Twenty-two participants performed a time- and safety-critical driving task that required rapidly gaining situation awareness through the side view displays/mirrors and making a lane change to avoid collision. The dependent variables were eye-off-the-road time, response time, and, ratings of perceived workload, preference and perceived safety. Overall, the layout placing the side view displays on the dashboard at each side of the steering wheel was found to be the best. The results indicated that reducing eye gaze travel distance and maintaining compatibility were both important for the design of CMS displays layout.

Practitioner Summary: A driving simulator study was conducted to comparatively evaluate three in-vehicle side view displays layouts for camera monitor systems (CMS) and the traditional side view mirror arrangement in critical lane changing situation. Reducing eye movement and maintaining compatibility were found to be both important for the ergonomics design of CMS displays layout.     

Colour names and focal colours on electronic displays

This study identified the colours that were perceived as being the best examples (focal colours) of 10 common colour names when viewed on an electronic display. A total of 204 colours derived from a reflective surface colour measurement system (Munsell) were converted to the Commission Internationale de l'Eclairage (CIE) 1976 system and presented on a cathode ray tube (CRT). Forty subjects chose what was perceived as the best examples for each of the following colour terms: purple, blue, aqua, green, yellow, orange, red, pink, grey, and white. Results show that focal colours on a CRT do not always correspond to the typical colours used or to the best examples for reflective surface colours. The display designer should consider these differences when selecting colours for a display.     

A first demonstration and analysis of the biprimary color system for reflective displays

A new biprimary color system is demonstrated for single‐layer reflective displays, capturing much of the improved color performance of multilayer displays while potentially maintaining single‐layer display advantages in high resolution and faster switching. Electrophoretic pixels were operated with dual‐particle complementary‐colored dispersions such as green/magenta (G/M). Using simple interdigitated three‐electrode architecture, four colored states (KWGM) were achieved with a preliminary contrast ratio of 10 : 1. Furthermore, biprimary ink dispersions were shown to be functional in a more advanced electrokinetic pixel structure. A full‐color biprimary pixel contains three complementary subpixels (G/M, B/Y, R/C), and the requisite electrophoretic ink dispersions were also formulated and spectrally characterized in this work. Lastly, theoretical color space mapping confirms that the biprimary concept provides twice the brightness and twice the color fraction compared with the conventional RGBW subpixel approach, and that the biprimary concept can approach performance close to that of magazine print (Specifications for Web‐Offset Print).     

Perceptions of electronic navigation displays

This study evaluated aesthetics and usability of in-vehicle electronic navigation maps. Experiment 1 examined map displays that varied in the amount of information presented, abstraction level, graphic/colour style and the existence of landmarks in both urban and rural environments using objective and subjective measures. Twenty participants performed navigation/localisation tasks using various map configurations while driving a driving simulator and completed usability and aesthetic questionnaires. The minimal detail map produced better performances and higher usability and aesthetic ratings when using maps with no landmarks. Adding information in the form of landmarks was found advantageous compared to additional textual information. Abstractions were most advantageous when combined with minimal amount of detail. Moderate abstractions were sufficient for obtaining the desired benefits when more details were present. The graphic/colour style affected subjective perceptions. Overall, high correlations were found for the perceived aesthetics and usability scales, however, low correlations were found between actual usability (i.e. performance) and perceived usability pointing to the importance of using both objective and subjective usability measures. Experiment 2 examined how maps varying in their aesthetic level (aesthetic versus non-aesthetic), different colour arrangements, and 2D versus 3D landmarks affect subjective and objective measures. Participants distinguished between usability and aesthetic perceptions and usability perceptions were less affected by aesthetics when the aesthetic level of the maps was low. Colour arrangement did not affect the measures examined. Both 2D and 3D landmarks were found to be aesthetic and usable. We conclude this article with guidelines for designing in-vehicle navigation map displays.     

Light-field head-mounted displays reduce the visual effort: A user study

Head-mounted displays (HMDs) allow the visualization of virtual content and the change of view perspectives in a virtual reality (VR). Besides entertainment purposes, such displays also find application in augmented reality, VR training, or tele-robotic systems. The quality of visual feedback plays a key role for the interaction performance in such setups. In the last years, high-end computers and displays led to the reduction of simulator sickness regarding nausea symptoms, while new visualization technologies are required to further reduce oculomotor and disorientation symptoms. The so-called vergence–accommodation conflict (VAC) in standard stereoscopic displays prevents intense use of 3D displays, so far. The VAC describes the visual mismatch between the projected stereoscopic 3D image and the optical distance to the HMD screen. This conflict can be solved by using displays with correct focal distance. The light-field HMD of this study provides a close-to-continuous depth and high image resolution enabling a highly natural visualization. This paper presents the first user-study on the visual comfort of light-field displays with a close-to-market HMD based on complex interaction tasks. The results provide first evidence that the light-field technology brings clear benefits to the user in terms of physical use comfort, workload, and depth matching performance.     

Multibeam and multipanel displays: Some perceptual effects of scan architecture

Abstract— Scan architectures involving multiple beams or panels provide a means of increasing display resolution. However, the spatiotemporal pattern of such a scan may differ appreciably from the sampling lattice of standard input devices. If there are discrepancies between the scan pattern used to display a sequence of spatial images and the sampling lattice used to create that sequence, the space‐time display image may not be an accurate reconstruction of the original image. To illustrate the types of error that can occur, this paper presents an analysis of the form and motion distortions that result when a standard, progressive scan is used to display computer‐generated constant‐velocity motion sequences. A summary of pertinent psychophysical research indicates why these distortions are rarely detectable and provides a basis for estimating the perceptual salience of distortions created by combinations of sampling lattices and scan patterns. Finally, an analysis of several possible parallel‐ scan architectures indicates that some will introduce relatively large temporal delays between updates of spatially adjacent areas and thereby seriously distort computer‐generated images.     

Reliability of transparent conducting substrates for rollable displays: A cyclic loading investigation

Abstract— Failure mechanisms for flexible conducting substrates are investigated herein in the context of rollable/flexible display applications. Cyclic loading experiments (substrates subjected to multiple cycles of tensile strain) were carried out on both ITO‐coated PET and PEDOT:PSS‐coated PET substrates. The resistance was measured after each bending cycle. The resistance increased with the number of cycles and was not reversible. Even when the tensile strain on the ITO/PET was below the virgin cracking threshold (～2%) previously reported [Appl Phys Lett ⁷⁶, 1425 (2000)], slight increases in resistance were measurable after just a few cycles.