There are several studies on estimating crosstalk of 3D displays. Crosstalk is an important factor in determining image quality of stereoscopic display. In previous study, gray to gray crosstalk model has been modified. In this paper, we use six commercial stereoscopic displays including passive polarized glasses and active shutter glasses, both left and right eyes were measured by a luminance meter to verify the gray to gray crosstalk model and analyze the stability of the measurement data using our standard operating procedure (SOP). According to the SOP, we use simple statistical method to verify the repeatability of data. Experimental results indicate that our measurement system can be used to estimate the value of gray to gray crosstalk of stereoscopic display, the uncertainty below 0.8% for FPR display and 3% for shutter glasses display at 95% confidence level. These results, can be used as an important parameters in stereoscopic display visual quality, also can be used as a design feedback for engineer.
The market of stereoscopic 3D TV grows up fast recently; however, for 3D TV really taking off, the interoperability of
shutter glasses (SG) to view different TV sets must be solved, so we developed a measurement method with ideal shutter
glasses (ISG) to separate time-sequential stereoscopic displays and SG. For measuring the crosstalk from time-sequential
stereoscopic 3D displays, the influences from SG must be eliminated. The advantages are that the sources to crosstalk are
distinguished, and the interoperability of SG is broadened. Hence, this paper proposed ideal shutter glasses, whose non-ideal
properties are eliminated, as a platform to evaluate the crosstalk purely from the display. In the ISG method, the
illuminance of the display was measured in time domain to analyze the system crosstalk SCT of the display. In this
experiment, the ISG method was used to measure SCT with a high-speed-response illuminance meter. From the time-resolved
illuminance signals, the slow time response of liquid crystal leading to SCT is visualized and quantified.
Furthermore, an intriguing phenomenon that SCT measured through SG increases with shortening view distance was
observed, and it may arise from LC leakage of the display and shutter leakage at large view angle. Thus, we measured
how LC and shutter leakage depending on view angle and verified our argument. Besides, we used the ISG method to
evaluate two displays.
Stereoscopic depth perception has been analyzed in many laboratory experiments since Wheatstone's (1838) discovery
that disparity is a sufficient and compelling stimulus for the perception of depth with mirror-type stereo displays. In this
paper, mirror-type stereo displays were used as the instrument to simulate the 3D image in the human factor experiment.
It can be used to simulate the 9 view 3D display by image processing method with different multi-view crosstalk levels
measured from luminance measurement device. The disparity of
multi-view images to form stereopsis with depth
perception is decided by the 9-view autostereoscopic 3D display that subject can properly fuse the image to get the
proper visual depth. Computer graphic method applied for multi-view content rendering with shooting distance of 70 cm
for each virtual camera. The distance between cameras is 5.6 cm with parallel capture to simulate the images accepted by
human eyes. The experimental design was used for testing subjective evaluations based on the questionnaire, and
ANOVA methods were used for analysis. Experimental variables of this human factor study for multi-view 3D display
are five levels of crosstalk distribution from measured data, with or without shadow effects and perspective line shown
within tested images. In addition, the result of acceptable system crosstalk level for multi-view stereoscopic display is
between Level 4.7 and Level 5.9 in average for the four tested images.
The ghost image induced by System-Crosstalk (SCT) of 3D display, due to optical hardware imperfections, is the major
factor to jeopardize stereopsis. The system crosstalk can be measured by optical measuring instrument and describes the
optical leakage from the neighboring viewing zones. The amount of crosstalk reduces the ability of the viewer to fuse the
stereo-images into 3D images. The Viewer-Crosstalk (VCT), combined with hardware and content issues, is an overall
evaluation of the ghost image and can be easily interpreted based on the principle of binocular 3D display. The
examination of different SCT values was carried out with a seven-grade subjective evaluation test. In our previous study,
it was shown that many other factors, such as contrast ratio, disparity and monocular cues of the images, play important
roles in the stereopsis. In this paper, we study the factors of stereo-images with different crosstalk levels that may affect
stereopsis. For simulate the interference between stereo-images, digital image processing are employed to assign
different levels of crosstalk to each other at properly specified disparity between images. Results of this research can
provide valuable reference to the content makers and for the optimized design of 3D displays with minimum System
Autostereoscopic displays have wider and wider applications, and optical quality evaluation is the bedrock for market
development. Unfortunately, we lack the 3D display measurement standard (3D DMS), human factor and even
standardized measurement instruments currently. Some studies reported the autostereoscopic display measurement using
current optical measurement instrument such as luminance meter, CCD and conoscope<sup>1</sup><sup>, </sup><sup>2, 3,</sup> <sup>4</sup>, but the problem now is
how to verify those data? In this paper, we measured the optimal viewing distance (OVD), designated eye positions
(DEP) and system-crosstalk of an autostereoscopic display and discussed some specific issues, like the affection of pupil
size and measurement distance, method to find out the OVD, etc. which is usually met in 3D display measurement, and
calculate the designated eye positions from the raw data using one-point method and two-point methods. The
measurement was made by a luminance meter and the results were compared to the designed parameters.
A multiview autostereoscopic LCD display with a localized 2D/3D switching function is developed based on the
actively switchable parallax barrier technology. This switchable barrier comprises of an electro-optically switchable
liquid crystal (LC) and a microretarder. Polymer dispersed liquid crystal (PDLC) with switchable clear and diffusing
states and twisted nematic liquid crystal (TNLC) with polarization switching function are used as switching devices. The
microretarder is prepared by self-developed multibeam laser scanning process, which is clean, friendly to the
environment, and easy for scale up and mass production. The influence factors on the image qualities of 3D displays
based on LCD panel technology are analyzed and discussed. Some solutions have proposed to solve the commercial
A microretarder for stereoscopic display is a film consisting of horizontal or vertical stripes with alternating null
and half-wave phase retardation states. An LCD with a microretarder attached on the front side can display good-quality
stereoscopic images when viewed with polarization glasses. It is now the easiest and cheapest way to present
stereoscopic images on a flat-panel display. However, the space caused by the glass between the retarder layer and the
LC layer of the panel seriously limits the vertical view angle, which, in turn, limits the application of this technology. In
this paper, a process for thin-film microretarder is developed using reactive liquid crystal. The material and the process
are essentially compatible with current LC panel processes. Since the thin-film microretarder is to be fabricated in the
cell of an LC panel, the retarder layer and the LC layer can be fabricated as close to each other as possible. A nearly
unlimited 3D view angle can be achieved for the display.
We investigated the spatial summation effect on pedestals with difference luminance. The targets were luminance modulation defined by Gaussian functions. The size of the Gaussian spot was determined by the scale parameter (standard deviation, σ) which ranged from 0.13°to 1.04°. The local luminance pedestal (2° radius) had mean luminance ranged from 2.9 to 29cd/m<sup>2</sup>. The no-pedestal condition had a mean luminance 58cd/m<sup>2</sup>. We used a QUEST adaptive threshold seeking procedure and 2AFC paradigm to measure the target contrast threshold at different target sizes (spatial summation curve) and pedestal luminance. The target threshold decreased as the target spatial extent increased with a slope -0.5 on log-log coordinates. However, if the target size was large enough (σ>0.3°), there was little, if any, threshold reduction as the target size further increased. The spatial summation curve had the same shape at all pedestal luminance levels. The effect of the pedestal was to shift the summation curve vertically on log-log coordinates. Hence, the size and the luminance effects on target detection are separable. The visibility of the Gaussian spot can be modeled by a function with a form f(L)*g(σ) where f(L) is a function of local luminance and g(σ) is a function of size.
Entertainment is usually considered an important application for stereoscopic display technologies. In order to provide more realistic and exciting VR effect, it is desirable to have as large screen as possible. However, the screen sizes of current autostereoscopic display technologies are limited by either the displaying panel or the optical components. In a government-sponsored project, we designed and fabricated a novel projection screen for autostereoscopic display. The screen consists of two layers of microretarder and a layer of polarization reserved diffuser. Both the screens and the projectors can be arrayed to build a large autostereoscopic display system. Curved or multi-plane screens are also possible. This kind of autostereoscopic display screen has the advantages of ease to scale up, low cost and no precise alignment between the projectors and the screen required. In this paper, the manufacture considerations of such a screen are studied and the experimental results are presented.
The ghost-image issue induced by crosstalk in stereoscopic, especially autostereoscopic, display systems has been believed to be a major factor to jeopardize stereopsis. Nevertheless, it is found that in some cases the stereopsis remains effective even with serious crosstalk. In fact, many other factors, such as contrast ratio, disparity, and monocular cues of the images, play important roles in the fusion of stereo images. In this paper, we study the factors in an image that may affect stereo fusion, and provide a macroscopic point of view to get a reasonable criterion of system crosstalk. Both natural and computer-generated images are used for detailed evaluation. Image processing techniques are adopted to produce desired characteristics. The results of this research shall be of reference value to content makers of stereoscopic displays, in addition to their designers.
3D image display devices have wide applications in medical and entertainment areas. Binocular (stereoscopic) imaging without glasses, especially spatial-multiplexed displays such as lenticular display, barrier strip display, and single-lens stereoscopic display, is one of the most powerful and popular ways for life-like presentation of our 3D environments. The definition and relationship of the image contrast and viewer crosstalk are reviewed and clarified. They are measured and compared on three different types of 3D display systems, including shutter-glasses stereoscopic display, image splitter autostereoscopic display and dual-panel autostereoscopic display.
A micro-retardation array is a plate consisting of two or more optical retardation states that are micro-patterned within different regions of the plate. A LCD panel with the micro-retardation array can be used to display stereoscopic images watched with or without special glasses by encoding right-eye image and left-eye image with periodically horizontal stripes of different polarization states. For example, the odd rows of stripes are assigned to have zero retardation and the even rows of stripes with a half- wavelength retardation or vice versa. The width of each stripe is of the order of hundreds of microns. This paper describes a fabrication process of micro-retardation array with high contrast ratio, well-defined stripe boundary and green process. The fact that the retardation property of polymer film will be changed by heat process is used in this fabrication process. It is shown that by accurately controlling the power and spot-size of a CO<SUB>2</SUB> laser, the retardation property of a polymeric film, such as PC and ARTON can be tailored within a localized area without altering the retardation of the untreated areas. In addition, the contrast ratios of micro-retardation array are measured and analyzed, the performance of an autostereoscopic display system using the micro-retardation array is also described.