Using cross‐talk simulation to predict the performance of anaglyph 3‐D glasses

Abstract— The anaglyph 3‐D method is a widely used technique for presenting stereoscopic 3‐D images. Its primary advantage is that it will work on any full‐color display (LCDs, plasmas, and even prints) and only requires that the user view the anaglyph image using a pair of anaglyph 3‐D glasses with usually one lens tinted red and the other lens tinted cyan (blue plus green). A common image‐quality problem of anaglyph 3‐D images is high levels of cross‐talk — the incomplete isolation of the left and right image channels such that each eye sees a “ghost” of the opposite perspective view. An anaglyph cross‐talk simulation model has been developed which allows the amount of anaglyph cross‐talk to be estimated based on the spectral characteristics of the anaglyph glasses and the display. The model is validated using a visual cross‐talk ranking test which indicates good agreement. The model is then used to consider two scenarios for the reduction of cross‐talk in anaglyph systems and finds that a considerable reduction is likely to be achieved by using spectrally pure displays. The study also finds that the 3‐D performance of commercial anaglyph glasses can be significantly better than handmade anaglyph glasses.     

Angular dependence of the performance of stereoscopic liquid‐crystal‐display (LCD) television using shutter glasses (SG)

Abstract— 3‐D cross‐talk typically represents the ratio of image overlap between the left and right views. For stereoscopic LCDs using shutter‐glasses technology, 3‐D cross‐talk for stereoscopic LCD TV with a diagonal size of 46 in. and vertical alignment (VA) mode was measured to change from 1% to 10% when the stereoscopic display is rotated around the vertical axis. Input signals consist of the left and right images that include patterns of different amounts of binocular disparity and various gray levels. Ghost‐like artifacts are observed. Furthermore, intensities of these artifacts are observed to change as the stereoscopic display is rotated about the vertical axis. The temporal luminance of the LCD used in stereoscopic TV was found to be dependent on the viewing direction and can be considered as one cause of the phenomenon of angular dependence of performance for stereoscopic displays.     

High‐resolution autostereoscopic 3‐D projection display with a space‐dividing iris‐plane shutter

Abstract— A high‐resolution autostereoscopic 3‐D projection display with a polarization‐control space dividing the iris‐plane liquid‐crystal shutter is proposed. The polarization‐control iris‐plane shutter can control the direction of stereo images without reducing the image quality of the microdis‐play. This autostereoscopic 3‐D projection display is 2‐D/3‐D switchable and has a high resolution and high luminance. In addition, it has no cross‐talk between the left and right viewing zones, a simple structure, and the capability to show multi‐view images.     

MUTED: Multi‐user 3‐D display

Abstract— Research described in this paper encompasses the design and building of glasses‐free (autostereoscopic) displays that utilize a direct‐view liquid‐crystal display whose backlight is provided by a projector and novel steering optics. This is controlled by the output of a multi‐user head‐position tracker. As the displays employ spatial multiplexing on a liquid‐crystal‐display screen, they are inherently 2‐D/3‐D switchable with 2‐D being achieved by simply displaying the same image in the left and right channels. Two prototypes are described in this paper; one incorporating a holographic projector and the other a conventional LCOS projector. The LCOS projector version addresses the limitations of brightness, cross‐talk, banding in the images, and laser stability that occur in the holographic projector version. The future development is considered and a comparison between the prototypes and with other 3‐D displays is given.     

Motion artifacts observed in 3‐D LCDs that use shutter glasses (SG 3D)

Abstract— Motion artifacts observed in 3‐D LCDs using shutter glasses (SG 3D) has been investigated. A ghost‐like artifact has been observed for static images due to incomplete image separation between the left and right views. The observed motion artifacts are different for the left and right views. And they occur even for images with zero binocular disparity. In this respect, the phenomena of observed artifacts in 3‐D moving images are differentfrom those of 3‐D static images. 3‐D motion artifacts were analyzed and are related to the moving speed of the images and the amount of binocular disparity.     

Influence of 3‐D cross‐talk on qualified viewing spaces in two‐ and multi‐view autostereoscopic displays

Abstract— To estimate the qualified viewing spaces for two‐ and multi‐view autostereoscopic displays, the relationship between image quality (image comfort, annoying ghost image, depth perception) and various pairings between 3‐D cross‐talk in the left and right views are studied subjectively using a two‐view autostereoscopic display and test charts for the left and right views with ghost images due to artificial 3‐D cross‐talk. The artificial 3‐D cross‐talk was tuned to simulate the view in the intermediate zone of the viewing spaces. It was shown that the stereoscopic images on a two‐view autostereoscopic display cause discomfort when they are observed by the eye in the intermediate zone between the viewing spaces. This is because the ghost image due to large 3‐D cross‐talk in the intermediate zone elicits different depth perception from the depth induced by the original images for the left and right views, so the observer's depth perception is confused. Image comfort is also shown to be better for multi‐views, especially the width of the viewing space, which is narrower than the interpupillary distance, where the parallax of the cross‐talking image is small.     

Switching directional BLUs for full‐resolution auto‐stereoscopic 3D/2D and 2D/3D LCDs

Directional backlight unit (BLU) design concept was applied to realize full‐resolution field alternate auto‐stereoscopic liquid crystal displays (LCDs) with built‐in 3D/2D and 2D/3D. The application‐oriented BLU design requires priority in realizing 2D mode or 3D mode. The switching characteristic of BLU with two confronting illuminating sets was applied to build 2D mode into 3D display and 3D mode into 2D display. An LCD with 2D mode as primary function requires higher double‐sided luminance uniformity than 3D mode. On the other hand, an LCD with 3D mode requires higher single‐sided luminance uniformity than 2D mode. For increasing the double‐sided luminance uniformity for 2D mode as a primary function of the display, the former BLU design was realized by using uniform prismatic structure, that is, using uniform bilateral prismatic structure with a cross section of isosceles triangle on the back surface of the light‐guide plate. For increasing single‐sided luminance uniformity for 3D mode as a primary function of the display, the latter was realized by using graded angle design, that is, unilateral prisms with a cross section of a scalene triangle on the back surface of the light‐guide plate. The LCDs of small‐sized‐handheld game devices and still cameras were fabricated using the 3D/2D and 2D/3D displays.     

Prototyping and optical evaluation of 9‐in. OCB time‐division‐multiplexing 18‐view 3‐D display

Abstract— An integral imaging time‐division‐multiplexing 18‐view 3‐D display based on the one‐dimensional integral‐imaging (1‐D‐II) technique using a 9‐in. OCB‐LCD, lenticular sheet, and active shutter has been developed. By simulating a lens shape and a shutter structure and analyzing the light‐beam profile of the increasing‐parallax‐number region to find the best conditions, depth range, and viewing angle were an enhanced and a brighter and flicker‐less 3‐D image with smooth motion parallax was obtained.     

A time‐sequential multi‐projector autostereoscopic display

Abstract— We describe a new 28‐view 25‐in. autostereoscopic display that combines both time‐sequential and multi‐projector technology. It is constructed from four time‐sequential subsystems, which abut behind a single ferroelectric liquid‐crystal shutter. The display has a resolution of 512 × 384 pixels in 24‐bit color. It allows multiple viewers to simultaneously view stereoscopic images without the need for special glasses or headgear.     

3‐D displays — Technologies and testing methods

Abstract— This paper is a review of stereoscopic 3‐D display technologies and testing methods. The first part addresses the different 3‐D displays with focus on technologies. It gives both a background and the logic to group the technologies into categories. A family‐tree chartsummarizes the technology map. This categorization allows for logical grouping of test methods. The second part is a summary of testing procedures developed as part of the ICDM (International Committee for Display Metrology) standards group, affiliated with SID (Society of Information Display). Definitions to key test parameters pertinent to the evaluation of stereoscopic 3‐D displays including formulae development will be presented. This review paper can serve as an introduction to the 3‐D & Stereoscopic Displays chapter of the IDMS (Information Display Measurement Standard) version 1.0 that will be issued by the ICDM group later this year. The IDMS v1.0 will be the successor of the FPDM‐2 from VESA.     

A common approach to characterizing autostereoscopic and polarization‐based 3‐D displays

Abstract— Autostereoscopic and polarization‐based stereoscopic 3‐D displays recreate 3‐D images by providing different images in the two eyes of an observer. This aim is achieved differently for these two families of 3‐D displays. It is shown that viewing‐angle measurements can be applied to characterize both types of displays. Viewing‐angle luminance measurements are made at different locations on the display surface for each view emitted by the display. For autostereoscopic displays, a Fourier‐optics instrument with an ultra‐high‐angular‐resolution VCMaster3D is used. For polarization‐based displays, a standard Fourier‐optics instrument with additional glass filters is used. Then, what will be seen by an observer in front of the display is computed. Monocular and binocular quality criteria (left‐ and right‐eye contrast, 3‐D contrast) was used to quantify the ability to perceive depth for any observer position. Qualified monocular and binocular viewing spaces (QMVS and QBVS) are deduced. Precise 3‐D characteristics are derived such as maximum 3‐D contrast, optical viewing freedom in each direction, color shifts, and standard contrast. A quantitative comparison between displays of all types becomes possible.     

2‐D/3‐D displays based on switchable lenticulars

Abstract— An attractive concept for 3‐D displays is the one based on LCDs equipped with lenticular lenses. This enables autostereoscopic multiview 3‐D displays without a loss in brightness. A general issue in multiview 3‐D displays is their relatively low spatial resolution because the pixels are divided among the different views. To overcome this problem, we have developed switchable displays, using liquid‐crystal (LC) filled switchable lenticulars. In this way, it is possible to have a high‐brightness 3‐D display capable of fully exploiting the native 2‐D resolution of the underlying LCD. The feasibility of LC‐filled switchable lenticulars was shown in several applications. For applications in which it is advantageous to be able to display 3‐D and 2‐D content simultaneously, a 42‐in. locally switchable prototype having a matrix electrode structure was developed. These displays were realized using cylindrically shaped lenticular lenses in contact with LC. An alternative for these are lenticulars based on gradient‐index (GRIN) LC lenses. Preliminary results for such switchable GRIN lenses are presented as well.     

A high resolution multi‐view 3D display using switchable liquid crystal lens

A 4.4‐inch 2D/3D switchable full high definition (FHD) six‐view 3D display with 3D resolution greater than 170 ppi has been accomplished. In addition to adopting low temperature polysilicon technology (LTPS), which is most suitable for high resolution displays, a new RGBW pixel arrangement using four‐square sub‐pixels has been devised. In 2D, a resolution greater than 500 ppi, accompanied with high luminance, has been achieved. A new liquid crystal lens (LCL) has been exploited for 2D/3D switching. By employing a special multielectrode structure and dedicated manufacturing process, an optical focal ratio less than 20%, which is essential for low 3D cross talk for a six‐view 3D display, has been attained by adopting the LCL. In the vertical direction of the display, there is no cross talk increase when the viewing position is changed because of the new pixel structure. The strong focal strength of the LCL combined with a revised high‐density multi‐view design give rise to a wide 3D viewing angle greater than 20 degrees in the horizontal direction and minimum cross talk less than 10%.     

Multi‐view 3‐D display employing a flat‐panel display with slanted pixel arrangement

Abstract— A flat‐panel display with a slanted subpixel arrangement has been developed for a multi‐view three‐dimensional (3‐D) display. A set of 3M × N subpixels (M × N subpixels for each R, G, and B color) corresponds to one of the cylindrical lenses, which constitutes a lenticular lens, to construct each 3‐D pixel of a multi‐view display that offers M × N views. Subpixels of the same color in each 3‐D pixel have different horizontal positions, and the R, G, and B subpixels are repeated in the horizontal direction. In addition, the ray‐emitting areas of the subpixels within a 3‐D pixel are continuous in the horizontal direction for each color. One of the vertical edges of each subpixel has the same horizontal position as the opposite vertical edge of another subpixel of the same color. Cross‐talk among viewing zones is theoretically zero. This structure is suitable for providing a large number of views. A liquid‐crystal panel having this slanted subpixel arrangement was fabricated to construct a mobile 3‐D display with 16 views and a 3‐D resolution of 256 × 192. A 3‐D pixel is comprised of 12 × 4 subpixels (M = 4 and N = 4). The screen size was 2.57 in.     

Moiré reduction by a diffuser in a multiview 3‐D imaging system

Abstract— Diffusers with different characteristics were inserted between the viewing‐zone forming optics and the image display panel of a contact‐type multiview 3‐D imaging system to examine their effects on moiré and cross‐talk in the system. The diffusers are effective in reducing the moiré but induce an increase in cross‐talk in most cases. However, a diffuser with the characteristics of a 200‐μm‐pitch lenticular diffuser or a scatter plate used in mobile phones can be used to reduce moiré because it does not cause any noticeable increase in the cross‐talk but still preserves the image properties without using a diffuser. This means that a diffuser can be used to reduce moiré in a contact‐type multiview 3‐D imaging system without significantly sacrificing image quality.     

Development of a 42‐in. 2‐D/3‐D switchable display using multi‐view technology for public‐information‐display applications

Abstract— A 42‐in. 2‐D/3‐D switchable display operating in a parallax‐barrier‐type system consisting of liquid‐crystal displays (LCDs) has been developed. The system displays 2‐D images in full resolution, without any degradation to the original 2‐D images, and 3‐D autostereoscopic images with resolutions higher than SVGA with wide viewing zones electrically controlled by the parallax‐barrier system. The system is intended for use in public‐information displays (PIDs), a booming field, and as displays for gaming, medical, and simulation applications.     

Optical simulation for cross‐talk evaluation and improvement of autostereoscopic 3‐D displays with a projector array

Abstract— Multi‐view spatial‐multiplexed autostereoscopic 3‐D displays normally use a 2‐D image source and divide the pixels to generate perspective images. Due to the reduction in the resolution of each perspective image for a large view number, a super‐high‐resolution 2‐D image source is required to achieve 3‐D image quality close to the standard of natural vision. This paper proposes an approach by tiling multiple projection images with a low magnification ratio from a microdisplay to resolve the resolution issue. Placing a lenticular array in front of the tiled projection image can lead to an autostereoscopic display. Image distortion and cross‐talk issues resulting from the projection lens and pixel structure of the microdisplay have been addressed with proper selection of the active pixel and adequate pixel grouping and masking. Optical simulation has shown that a 37‐in. 12‐view autostereoscopic display with a full‐HD (1920 × 1080) resolution can be achieved with the proposed 3‐D architecture.     

Psychophysical evaluations of a current multi‐view 3‐D display: Its advantages in glossiness reproduction

Abstract— Although two‐view 3‐D displays requiring stereo glasses are on the market, the shape of objects they present is distorted when the observer's head moves. This problem can be solved by using a (passive) multi‐view 3‐D display because such a display can produce motion parallax. Another problem has to do with the surface quality of the presented object, but little is known about the fidelity of such displays as far as the surface quality goes. Previously, it was found that a two‐view 3‐D display has a problem in which glossiness deteriorates when the observer's head moves and that it can be alleviated by using a head tracker, whose data enables the display to produce correct motion parallax and luminance changes when the viewer's head moves. Here, it was determined whether this problem can be solved by using commercially available multi‐view 3‐D displays, whose finite number of viewpoints and certain amount of cross‐talk, however, make luminance changes inexact and smaller than they should be. It was found that this display can solve the problem to a certain extent.     

Retracted: Computer‐aided ergonomics and visualization for improving 3D display techniques

Although there have been numerous studies regarding three‐dimensional (3D) display techniques and Flash technology, there has been little discussion of how to apply the 3D display technique to Flash applications. In this study, we develop a method that uses passive 3D display glasses, which are cheaper than other 3D display techniques, to reduce the cost and popularize this technique for web applications. The 3D red‐blue filter glasses are inexpensive and can be manufactured easily. We also look at how to construct a Flash game and test its 3D effects using the red‐blue filter glasses. © 2012 Wiley Periodicals, Inc.     

A novel quarter‐wave retardation film for improving viewing angle properties in time‐sequential stereoscopic 3D‐LCDs

We have successfully developed a quarter‐wave retardation film (QWF) for wide viewing angle 3D liquid crystal displays (3D‐LCDs) that provides high luminance, low crosstalk, low color change, and low head‐tilt‐angle dependency. It was found that the out‐of‐plane retardation (Rth) of the QWF in the LCD needs to be close to 0 nm in order to improve the 3D display properties at an off‐axis position and that the in‐plane retardation (Re) needs to be adjusted from 120 to 130 nm to achieve low color change with head tilting. We adopted a coating process for making our QWF because of its potential for retardation control. 3D‐LCDs with this QWF whose Rth was nearly zero had high performance and allowed off‐axis other than on‐axis.