Ai-Hong Wang

Autostereoscopic display based on two-layer lenticular lenses

An autostereoscopic display based on two-layer lenticular lenses is proposed. The two-layer lenticular lenses include one-layer conventional lenticular lenses and additional one-layer concentrating-light lenticular lenses. Two prototypes of the proposed and conventional autostereoscopic displays are developed. At the optimum three-dimensional view distance, the luminance distribution of the prototypes along the horizontal direction is measured. By calculating the luminance distribution, the crosstalk of the prototypes is obtained. Compared with the conventional autostereoscopic display, the proposed autostereoscopic display has less crosstalk, a wider view angle, and higher efficiency of light utilization.

Image Processing to Eliminate Crosstalk Between Neighboring View Images in Three-Dimensional Lenticular Display

In the multiview autostereoscopic 3D lenticular displays, the crosstalk between the neighboring view images at each view images optimal viewing position influences the image quality and lowers the visual comfort of observers. A method is proposed to eliminate the crosstalk by correcting the intensity values of subpixels on synthetic images. We analyze the causes of crosstalk based on a synthetic image and deduce the equations of crosstalk elimination according to the relationship between the crosstalk coefficients of each view image observed through the lenticular sheet, the intensity values of subpixels displayed on the synthetic images, and the intensity values of subpixels observed through the lenticular sheet at the optimal viewing position. The experiment results verify the effectiveness of the proposed method. The method for crosstalk elimination is by means of image processing, and it does not change the parameters of the lenticular lens and the structure of the display screen.

Cross-talk reduction by correcting the subpixel position in a multiview autostereoscopic three-dimensional display based on a lenticular sheet

A method is proposed to alleviate the cross talk in multiview autostereoscopic three-dimensional displays based on a lenticular sheet. We analyze the positional relationship between subpixels on the image panel and the lenticular sheet. According to this relationship, optimal synthetic images are synthesized to minimize cross talk by correcting the positions of subpixels on the image panel. Experimental results show that the proposed method significantly reduces the cross talk of view images and improves the quality of stereoscopic images.

Crosstalk reduction in multi-view autostereoscopic three-dimensional display based on lenticular sheet

A method to reduce crosstalk in multi-view autostereoscopic three-dimensional (3D) displays based on the lenticular sheet is proposed. Correcting the luminance values of each parallax image displayed on the display screen is employed. We analyze the causes of crosstalk. We deduce the formulas of crosstalk reduction according to the relationship between crosstalk coefficients of each parallax image observed through the lenticular sheet, luminance values of each parallax image displayed on the display screen, and luminance values of each parallax image observed through the lenticular sheet at each viewing position. Experimental results verify the effectiveness of the proposed method.

Stereo viewing zone in autostereoscopic display based on parallax barrier

A well-designed autostereoscopic display based on parallax barrier can produce high-quality stereo images without crosstalk in the stereo viewing zones. The concept of stereo image quality factor was defined to indicate the stereo viewing zone of the display. The stereo viewing zone was analyzed using geometry principle. Simulated program was developed to calculate the stereo viewing zone. The calculated results of an autostereoscopic display monitor were given and the stereo viewing zone was obtained by defining threshold value of stereo image quality factor.

Depth‐map generation for multi‐view autostereoscopic 3‐D displays based on the SIFT algorithm constrained by boundary

— A depth-map estimation method, which converts two-dimensional images into three-dimensional (3-D) images for multi-view autostereoscopic 3-D displays, is presented. The proposed method utilizes the Scale Invariant Feature Transform (SIFT) matching algorithm to create the sparse depth map. The image boundaries are labeled by using the Sobel operator. A dense depth map is obtained by using the Zero-Mean Normalized Cross-Correlation (ZNCC) propagation matching method, which is constrained by the labeled boundaries. Finally, by using depth rendering, the parallax images are generated and synthesized into a stereoscopic image for multi-view autostereoscopic 3-D displays. Experimental results show that this scheme achieves good performances on both parallax image generation and multi-view autostereoscopic 3-D displays.

Elimination of vertical parallax in multi-view parallax images

In three-dimensional displays, large vertical parallax in parallax images is disadvantageous to stereo vision due to the presence of visual fatigue. Based on the principle that homologous points in different parallax images correspond to the same object point, a method is proposed to eliminate the vertical parallax in multi-view parallax images. The coordinate mapping relationship between a standard parallax image and an awaiting rectification parallax image is established according to the coordinates of the image points of the rectangular calibration board vertices. Experiments are conducted, and results prove that the proposed method is reliable.

Stereoscopic Image Acquisition and Autostereoscopic Display

Stereoscopic image acquisition and stereoscopic three dimensional (3D) displays are interdependent and inseparable. The scenes reproduced in 3D displays are captured by stereoscopic image acquisition, and the contents obtained by stereoscopic image acquisition are finally shown in 3D displays. The paper reviews various layout structures of the stereo cameras and their advantages and advantages. The structures, principles and properties of parallax barrier and lenticular lens autostereoscopic 3D displays are also expounded in the paper.

Virtual toed-in camera method to eliminate parallax distortions of stereoscopic images for stereoscopic displays

— The parallax images captured by a toed-in camera have positive and negative horizontal parallax for stereoscopic displays, but they also have parallax distortions including horizontal and vertical distortions. The virtual toed-in camera method can eliminate the horizontal distortion and reduce the vertical distortion. The parallax formulae for the corrected-parallax images were deduced. The experiments were carried out and the results proved that the method was accurate. Good stereoscopic images without horizontal distortion and with little vertical distortion were presented on an autostereoscopic display.