Lenticular Lens Sheet Research Articles

P‐4.11: Autostereoscopic Three‐dimensional Display with Proper Slanted Angle

A method for estimating the proper slanted angle of an autostereoscopic lenticular lens sheet is proposed in this paper. A three‐dimensional(3D) display with the proper slanted lenticular lens sheet has the lower three‐dimension al(3D) crosstalk and less moiré pattern. To get the proper angle, a mathematical model describing the optical performance of the lenticular lens is established on the Snell's law and the ray tracing method. In this model, the shapes and the distribution of the display's subpixels are introduced as an important element to affect the slanted angle. A15.6” 3D display designed by this method is reported with a lower crosstalk and better 3D performance.

Correction of distorted 3-D images for misalignment of an optical structure in a multiview 3-D display system

For a multiview three-dimensional (3-D) display system using a two-dimensional (2-D) flat panel display, it is very important to attach accurately an optical plate such as a parallax barrier and a lenticular lens sheet onto a 2-D display panel for the best quality of 3-D images. In most practical cases, however, misalignment occurs since it is too difficult to align perfectly in assembly process. In general, angular misalignment results in the deterioration of 3-D image quality by some increase of crosstalk, so that the resulting 3-D images are even distorted as tilted ones. To correct distorted 3-D images, we propose a method to skew 3-D objects before each image for multiviews is taken by multiple cameras. For this, a formula is derived to determine the amount of skewing 3-D objects. And by using it, some experimental results are shown that distorted 3-D images in a misaligned multiview 3-D display system are completely corrected. Since skewing 3-D objects implies a coordinate transformation of 3-D space, this method can be also used in the manipulation of 3-D image data obtained from a depth camera in order to correct the distorted 3-D images caused by angular misalignment.

P‐96: Autostereoscopic Three‐dimensional Display Based on Sparse Lenticular Lens Sheet

Crosstalk is a primary factor in effecting the image quality of stereoscopic three dimensional (3D) displays. In this paper, we propose an autostereoscopic three‐dimensional (3D) display based on a sparse lenticular lens to reduce crosstalk and improve stereoscopic image quality. The sparse lenticular lens sheet includes a lenticular lens sheet and a light‐proof stripe array. To illustrate the superiority of the proposed display, a prototype is developed. The luminance distribution of each viewpoint at the optimum distance is measured. The results show that the proposed autostereoscopic 3D display presents clearer stereoscopic images and lower crosstalk compared with the conventional one.

A new LCL-lens array with electrodes of interlaced structure to be applied for auto-stereoscopic 3D displays

A new design of the liquid crystal lenticular (LCL) lens array with interlaced electrodes is proposed to realize an auto-stereoscopic 3D display. The structure of interlaced electrodes aims to generate a desired non-uniform electric filed to improve the focusing ability of the LCL-lens array with lower voltage drives. This paper is organized as first to describe the design criteria of a lenticular lens sheet for wide extended graphics array LCD panel. Based on the designed lenticular lens array, an LCL-lens array with proposed interlaced electrodes is next designed. The fabrication and the detailed structure are given. A series of experiments are then conducted and successfully verify the focusing capability and desired 3D display functions, that is, to separate two images to right and left eyes. Also, the developed auto-stereoscopic 3D display is able to adapt to varied viewer locations with favorable imaging quality.

Analysis of a color-matching backlight system using a blazed grating and a lenticular lens array

A high efficiency LCD employing a color-matching backlight system that consists of a collimation lenticular lens sheet, a blazed grating, and a focusing lenticular lens array is proposed and analyzed. The RGB lights that are collimated and dispersed from the collimation lenticular lens sheet and the blazed grating are incident on the RGB color filters by the focusing lenticular lens array. The color-matched transmittance was increased 183% and 121% for divergence angles of 2° and 11°, respectively, compared to a conventional backlight that does not use a blazed grating. The design, simulation, and experimental results for the prototype color-matching backlight system are presented.

프로젝션 기반 무안경 방식 멀티뷰 3D 디스플레이에서 구면 렌티큐라 렌즈 시트를 이용하여 재생된 입체영상의 해상도를 증가시키는 광학적 접근 방법

Multi-view 3D displays based on a limited number of pixels have the problem that the stereo-scopic image has a low resolution because of increasing view number. To solve the problem of low resolution, we propose an optical approaching method that focuses the width of a unit pixel by using a commercial spherical shape lenticular lens sheet and increases the effective resolution by increasing the number of sources of light in the multi-view 3D display system based on projection type. The method was performed in such an order that several main derivable parameters were defined, and, through the theoretical and experimental result, the value of the contractible unit pixel width and the scalable effective resolution was derived in a given system environment. As a result, for the case that the ray of light from the projector transmitted the 25 LPI lenticular lens sheet which has the pitch size 1.016 mm, the focused unit pixel width was 0.19 mm and the scalable effective resolution was, at most, 5 times wider than the original one. In addition, the range of depth of focus was 1.496 mm, which shows us the range of thickness tolerances of commercial spherical shape lenticular lens sheet and sufficient optical alignment tolerances.

Cross-lenticular lens array for full parallax 3-D display with crosstalk reduction

As a 3-D display technology, stereoscopic imaging with lenticular lens sheet can only offer viewers the horizontal parallax. To reconstruct the 3-D image with parallax in both horizontal and vertical directions, the full parallax technique with micro-lens array was proposed. But due to the fabrication constraints and cost concerns of the micro-lens array, application of the full parallax technique is restricted in practice. In this paper we revisited the lenticular sheet method and cross-lenticular lens array formed by two lenticular sheets overlapped orthogonally. By analyzing the optical properties of this cross-lenticular lens array, we found that it has reasonable imaging qualities as a conventional micro-lens array. Besides, due to the poor optical property of the outskirt area of the cross-lenticular lens, the cross-lenticular lens array has better crosstalk suppression capability than the conventional one. Based on the analysis, in this paper, we used the proposed lens array to reconstruct a 3-D image and verified its practicability. The cross-lenticular lens array was found feasible to take the full parallax technique into commercial applications, with comparable advantages in terms of low-cost and easy fabrication over a large area.

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.

TFT-LCD의 3차원 영상출력을 위한 렌티큘러 렌즈 최적설계

In this study, we have researched the optimum design method of the lenticular lens sheet for 3D displays on a TFT-LCD panel, to offer a more stable stereoscopic image, improved 3D quality, and a wider viewing zone. Especially, we have defined the viewing zone width (a parameter denoted as Z) to apply it to the optimum design. The results of this new design method have been compared with the existing design method. As a result, it is revealed that the proposed design method improves the stereoscopic image quality by reducing the black matrix zone width.

A study on the expression of motion graphics that to be using lenticular lens sheets

A study on the expression of motion graphics that to be using lenticular lens sheets

20.1: Mobile 3D Displays Based on a LTPS 2.4” VGA LCD Panel Attached with Lenticular Lens Sheets

AbstractWe developed the prototypes of 2‐view and multi‐view 3D displays based on LTPS 2.4″ VGA LCD panel with lenticular lens array sheets. In case of a 2‐view 3D, we attached the lens sheets, appropriate to a fine pitch LCD, in front of the panel. Throughout the advantage of high resolution, good 3D image quality was achieved with thinness and high brightness. for a multi‐view 3D, due to its large view number, smooth motion parallax and low visual fatigue are observed. From the results, we believe that the VGA LCDs with lenticular lens sheets are suitable for the application of the mobile 3D displays.

조명각 변조 방식의 3차원 입체영상 표시장치설계 및 공차분석

In order to realize a 3-D stereoscopic display module with alternating illumination angles, several conditions required for a lenticular lens sheet were established, and then both the lens specification and the module structure were designed. Also the performance of the stereoscopic module and its tolerance characteristics were evaluated by simulating the intensity distribution on the observation plane with a finite-ray tracing technique. From the evaluation, it was known that an intersection area between two adjacent lenses should not be filled and that the lateral mismatch between a planar liquid crystal shutter and a lens sheet should be minimized.

32.3: An Eyeglass‐Free Rear‐Cross‐Lenticular 3‐D Display

AbstractWe have developed a new method of an eyeglass‐free stereoscopic display, which we call “Rear‐Cross‐Lenticular 3‐D Display” (RCL3D). The RCL3D consists of a LCD panel, two lenticular lens sheets which run perpendicular to each other, a Checkered Pattern Mask and a backlight panel. On the LCD panel, a composite image which consists of alternately arranged horizontally striped images for right eye and left eye, is displayed. This composite image form is compatible with the field sequential stereoscopic image data. We made prototype of the RCL3D (14.5″, XGA) and confined the good quality of the stereoscopic 3‐D images. But there is slight crosstalk with the prototype. The measured crosstalk is around 5%. According to the results of a simulation of illumination profile in viewing zone, LCD with less reflectance and scattering is expected for RCL3D to reduce the crosstalk.