Autostereoscopic display based on multi-layer lenticular lens

An autostereoscopic display based on a multi-layer lenticular lens was proposed. The autostereoscopic display is composed of a flat panel display and a multi-layer lenticular lens sheet, which includes a traditional single lenticular lens and an additional transparent layer. The focal length of the multi-layer lenticular lens can be changed by choosing the refractive index of the additional transparent layer to adjust the stereoscopic depth, and it is an easier and much more flexible way than changing lenticular lens's curvature radius. A 22-in. 9-view autostereoscopic display prototype was developed. The image crosstalk of the prototype is very small and it has good presentation to several viewers without wearing eyeglasses.     

基于插值算法的立体显示的图像合成与嵌入式实现

在多视点自由立体显示中,针对柱透镜光栅参数与显示器像素不匹配造成的串扰问题,提出利用图像插值的合成方法对图像进行缩放处理。以9视点为例,提出缩放比例系数k,实现双线性插值算法的改进。嵌入式样机测试结果表明,该方法能够满足显示器像素宽度与柱透镜参数的完全匹配,串扰度从13.55%降低到1.40%,降低了12.15%,图像分辨率明显提高,立体显示效果更好。     

Crosstalk elimination in multi-view autostereoscopic display based on polarized lenticular lens array

An autostereoscopic display composed of a directional backlight,an image display panel,a striped half-wave plate,and a polarized lenticular lens array is proposed.The directional backlight emitting the parallel light can redirect the cones of light to lenticular lens array and reduce the chromatic spatial-interference effect.The striped half-wave plate,located in front of the image display panel,transformed the polarization direction of the lights from the directional backlight into two mutually perpendicular directions.The polarized lenticular lens array not only can divide the light from the left and right view images to send to left and right eyes but also can reduce the crosstalk of the stereoscopic images.The proposed autostereoscopic display can produce high quality stereoscopic images without crosstalk at the optimal viewing distance.     

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,...     

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.     

立体显示用柱面透镜光栅的设计

分析了柱面透镜光栅的单柱面透镜的光传输特性,进而推导出柱面透镜光栅的曲率半径、节距和厚度等重要参量的计算公式.根据这些理论公式,为15英寸柱面透镜光栅自由立体显示器设计了柱面透镜光栅的参量,通过应用光学软件ASAP模拟该立体显示器的立体视区分布,得出该立体显示器能显示良好立体图像,从而验证了理论的正确性.     

消除自由立体显示串扰的定向背光源设计

定向背光柱透镜光栅式多视点自由立体显示器的串扰和亮度均匀性问题是影响其广泛应用的主要因素之一.本文通过分析串扰产生的原因,根据偏轴光线的成像光学原理,推导出液晶显示屏光开关板列单元与柱透镜组成的偏轴光学系统的参数计算式.提出一种液晶显示屏光开关蝶形单元结构,设计了采用该蝶形单元的定向背光自由立体显示背光源模组.模拟仿真结果表明:所设计的定向背光自由立体显示背光源可消除自由立体显示的串扰;在视点平面90%观看区域的串扰度小于0.5%,光束10%峰值宽度的串扰面积比γ=0,光束90%峰值宽度比普通液晶单元结构的增大37%,改善了不同位置观看图像亮度变化大的问题.     

裸眼3D LED显示的全息透镜板在线拼接的检测方法

全息透镜板的高精度拼接与装配是基于全息透镜技术的大屏幕LED裸眼3D显示系统搭建中的关键问题。理论计算与实验结果表明,全息透镜板与LED显示模组横向相对位置误差小于1.332mm时,可以满足显示的要求。基于裸眼3D显示系统的投射条纹,提出了基于投射条纹的全息透镜板位置实时调整方法。依据此方法提出了基于极大值测量条纹中心间距的图像处理算法,并结合LabView编写了图像处理程序。实验结果表明,使用该方法测得的亮暗条纹间距的测量精度为0.1mm,反算出全息透镜板与LED屏之间的位置误差小于0.03mm,满足实时调整全息透镜板位置的要求,可以作为全息透镜板在线拼接的检测方法。     

One-dimensional integral imaging based on parallax barrier

One-dimensional integral imaging (1DII) which only has horizontal disparity is a practical solution of high resolution in the vertical direction, low-cost, easy-viewable three-dimensional (3D) display. A 1DII based on a parallax barrier is proposed in this paper. The 1DII consists of a parallax barrier and a display panel. The operation principle and parameter calculation of the 1DII are described in detail. Two prototypes of the proposed 1DII and conventional 1DII based on a lenticular lens array are developed. The proposed 1DII improves the quality of the 3D image and provides larger viewing angle than that based on a lenticular lens array, and it is simpler and has lower cost than that based on a lenticular lens array.     

3D display with uniform resolution and low crosstalk based on two parallax interleaved barriers

The resolution of the parallax image is inversely proportional to the view number in the horizontal direction for the traditional autostereoscopic display based on a parallax barrier. To balance the resolution in the vertical and horizontal directions, two parallax interleaved barriers are designed. The liquid crystal display panel provides the synthetic image with square pixel units, and the pixels in a unit are distributed to different horizontal views. Two parallax interleaved barriers work together to modulate pixels in vertical and horizontal directions. 3D display with uniform resolution and low crosstalk is demonstrated.     

Stereo viewing zone in parallax-barrier-based autostereoscopic display

A well-designed parallax barrier autostereoscopic display can produce high-quality stereo images with little crosstalk or even without crosstalk in the stereo viewing zones. The concept of stereo image quality factor was defined to indicate the stereo viewing zone of an autostereoscopic display. According to the structure and principle of the display, the formulae of stereo image quality factor were deduced. Simulated program was developed to calculate stereo image quality factor. The simulated results of stereo image quality factor for a 19-in autostereoscopic display monitor show that stereo image quality factor can indicate the stereo viewing zone of autostereoscopic displays. The simulated results also show that the value of stereo image quality factor is equal to 1 at only few positions where viewers can see very good stereo images without crosstalk. And the viewers who stay at the optimal viewing distance can see the best stereo images on the display screen. The research of the stereo viewing zone helps in the design of such autostereoscopic display devices with little or without crosstalk.     

Autostereoscopic 3D projection display based on two lenticular sheets

We propose an autostereoscopic three-dimensional (3D) projection display. The display consists of four projectors, a projection screen, and two lenticular sheets. The operation principle and calculation equations are described in detail and the parallax images are corrected by means of homography. A 50-inch autostereoscopic 3D projection display prototype is developed. The normalized luminance distributions of viewing zones from the simulation and the measurement are given. Results agree well with the designed values. The proposed prototype presents full-resolution 3D images similar to the conventional prototype based on two parallax barriers. Moreover, the proposed prototype shows considerably higher brightness and efficiency of light utilization.     

基于自由曲面的裸眼3D显示柱透镜光栅设计

设计了一种用于裸眼3D显示屏的低串扰新型双面柱透镜光栅板,光栅板的入射面为等间距排列的与显示器子像素数量相同的凹形自由曲面光栅结构,出射面为斜置的凸形自由曲面光栅结构.根据裸眼3D显示原理和几何光学原理推导了双面光栅板的光栅单元自由曲面设计公式和光栅参数计算公式.通过MATLAB编程计算和SolidWorks软件建模得到光栅板模型.用TracePro软件对所设计的光栅板模型进行光线追迹仿真,结果表明:参数优化后的6视点斜置柱透镜双面光栅3D显示在最佳视角的图像串扰度为0.068%,与传统6视点斜置柱透镜光栅的最佳视角图像串扰度相比降低了2个数量级,并且在观看距离2 000mm~3 000mm范围内图像串扰度基本不变.     

狭缝光栅、柱面透镜光栅及其新构型在三维显示中的应用

介绍了三维显示技术的研究现状,综述了狭缝光栅和柱面透镜光栅在自由立体显示技术中的重要应用。回顾了各种光栅式自由立体显示系统的结构和原理;提出了如何根据狭缝光栅和柱面透镜光栅的特殊光学性质,在传统的立体显示系统中添加各种光栅形成灵活组合结构来提高立体显示效果,强调了它们在减小串扰、增大视场角、避免摩尔条纹以及提供更全面的三维信息等方面的作用。最后指出基于两种光栅的叠加构成面积大、参数均匀、价格低廉的新型透镜可实现全视差立体显示,对探索自由立体显示技术的研究很有意义。     

狭缝光栅、柱面透镜光栅及其新构型在三维显示中的应用

介绍了三维显示技术的研究现状,综述了狭缝光栅和柱面透镜光栅在自由立体显示技术中的重要应用。回顾了各种光栅式自由立体显示系统的结构和原理;提出了如何根据狭缝光栅和柱面透镜光栅的特殊光学性质,在传统的立体显示系统中添加各种光栅形成灵活组合结构来提高立体显示效果,强调了它们在减小串扰、增大视场角、避免摩尔条纹以及提供更全面的三维信息等方面的作用。最后指出基于两种光栅的叠加构成面积大、参数均匀、价格低廉的新型透镜可实现全视差立体显示,对探索自由立体显示技术的研究很有意义。     

Shared pixel based parallax barrier 3D display with high brightness

The parallax barrier 3D display is an autostereoscopic display with low cost. However, the conventional parallax barrier 3D display has a disadvantage of low brightness. Therefore, a parallax barrier 3D display based on shared pixels is proposed. The shared pixels have adapted pixel values which limit crosstalk in a low level, so that they can be displayed simultaneously in both two parallax images. These pixels increase aperture ratio of the parallax barrier. Therefore, they can bring high brightness. A prototype of the proposed 3D display is developed and it has higher brightness than those based on the conventional one.     

A 3D image interleaving method for real-time autostereoscopic display based on GPU

Multiview autostereoscopic systems display three-dimensional (3D) images interleaved from parallax images to provide adequate viewing zones for viewers. A 3D image interleaving method based on parallel processing with Graphic Processing Unit (GPU) is proposed to accelerate the image interleaving for real-time autostereoscopic displays. The proposed method is implemented with Direct3D Application Programming Interface (API) library. Masks used to interleave the 3D images are generated according to some particular principles. Both multiple texture blending and alpha blending operations are used to interleave a 3D image. The experiments prove that high interleaving efficiency and good stereoscopic sense can be obtained. The proposed method meets the requirement of real-time multiview autostereoscopic displays and avoids extra shader program.     

平面三维显示技术的研究现状

平面三维显示技术是近年来最新出现的虚拟现实显示技术,其最大的特点是观察者无需使用任何辅助附加设备,直接用肉眼就可看到屏幕上显示的三维图像。为推进三维显示技术的发展,进一步研究了视差立体成像原理,并据此介绍几种平面三维显示方法及其工作原理,包括障栅立体显示、微柱透镜阵列立体显示、偏振片立体显示和基于微柱透镜立体显示原理的多视点系统,阐述并分析了系统的优缺点。以日本三洋公司的四视角立体显示装置、南京大学的多视点三维显示系统和NEC液晶科技的HDDP三维显示系统为例,描述了国内外该项技术近期的研究现状,分析了存在的技术难点,展望了该应用领域的发展前景。     

Micro-projection dynamic backlight for multi-view 3D display

A micro-projection dynamic backlight for multi-view three-dimensional(3 D) display is proposed. The proposed backlight includes a light emitting diodes(LEDs) array, a lenticular lens array, and a scattering film. The LED array, the lenticular lens,and the scattering film construct a micro-projection structure. In this structure, the LEDs in the array are divided into several groups. The light from each LED group can be projected to the scattering film by the lenticular lens and forms a series of bright stripes. The different LED groups have different horizontal positions, so these bright stripes corresponding to different LED groups also have different horizontal positions. Therefore, they can be used as a dynamic backlight.Because the distance between the LEDs array and the lenticular lens is much larger than the distance between the lenticular lens and the scattering films, the imaging progress will make the width of the bright stripes much smaller than that of the LEDs, and the pitch of the stripes is also decreased. According to the 3 D display theory, the bright stripes with small width and pitch help to increase the number of views. Therefore, the proposed micro-projection dynamic backlight is very suitable for multi-view 3 D display. An experimental prototype was developed, and the experimental results show that the micro-projection dynamic backlight can correctly complete the directional projection of the parallax images to form a 3 D display.     

Autostereoscopic three-dimensional display with high dense views and the narrow structure pitch

An auto-stereoscopic three-dimensional （3D） display method with the narrow structure pitch and high dense viewpoints is presented. Normally, the number of views is proportional to the structure pitch of the lenticular lens array. Increasing the density of views will decrease the spatial display resolution. Here a lenticular lens array with one pitch covering 5.333 subpiexels and a novel subpixel arrangement method are designed, and a 32 view 3D display is demonstrated. Compared with the traditional 6-view 3D display, the angular resolution and the displayed depth of field are significantly improved.