WO2015168969A1 - 基于振动光栅的裸眼立体显示方法与装置 - Google Patents

基于振动光栅的裸眼立体显示方法与装置 Download PDF

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Publication number
WO2015168969A1
WO2015168969A1 PCT/CN2014/078686 CN2014078686W WO2015168969A1 WO 2015168969 A1 WO2015168969 A1 WO 2015168969A1 CN 2014078686 W CN2014078686 W CN 2014078686W WO 2015168969 A1 WO2015168969 A1 WO 2015168969A1
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grating
stereoscopic
image
pixel
display
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French (fr)
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侯春萍
王晓燕
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Tianjin University
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Tianjin University
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N13/00—Stereoscopic video systems; Multi-view video systems; Details thereof
    • H04N13/30—Image reproducers
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B30/00—Optical systems or apparatus for producing three-dimensional [3D] effects, e.g. stereoscopic images
    • G02B30/20—Optical systems or apparatus for producing three-dimensional [3D] effects, e.g. stereoscopic images by providing first and second parallax images to an observer's left and right eyes
    • G02B30/26—Optical systems or apparatus for producing three-dimensional [3D] effects, e.g. stereoscopic images by providing first and second parallax images to an observer's left and right eyes of the autostereoscopic type
    • G02B30/27—Optical systems or apparatus for producing three-dimensional [3D] effects, e.g. stereoscopic images by providing first and second parallax images to an observer's left and right eyes of the autostereoscopic type involving lenticular arrays
    • G02B30/29—Optical systems or apparatus for producing three-dimensional [3D] effects, e.g. stereoscopic images by providing first and second parallax images to an observer's left and right eyes of the autostereoscopic type involving lenticular arrays characterised by the geometry of the lenticular array, e.g. slanted arrays, irregular arrays or arrays of varying shape or size
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B30/00—Optical systems or apparatus for producing three-dimensional [3D] effects, e.g. stereoscopic images
    • G02B30/20—Optical systems or apparatus for producing three-dimensional [3D] effects, e.g. stereoscopic images by providing first and second parallax images to an observer's left and right eyes
    • G02B30/26—Optical systems or apparatus for producing three-dimensional [3D] effects, e.g. stereoscopic images by providing first and second parallax images to an observer's left and right eyes of the autostereoscopic type
    • G02B30/30—Optical systems or apparatus for producing three-dimensional [3D] effects, e.g. stereoscopic images by providing first and second parallax images to an observer's left and right eyes of the autostereoscopic type involving parallax barriers
    • G02B30/32—Optical systems or apparatus for producing three-dimensional [3D] effects, e.g. stereoscopic images by providing first and second parallax images to an observer's left and right eyes of the autostereoscopic type involving parallax barriers characterised by the geometry of the parallax barriers, e.g. staggered barriers, slanted parallax arrays or parallax arrays of varying shape or size

Definitions

  • the present invention relates to the field of naked eye three-dimensional stereoscopic display technology, and more particularly to an apparatus and a principle for increasing a stereoscopic viewing zone of a naked eye three-dimensional display while maintaining high resolution of a stereoscopic image. Specifically, it relates to a naked eye stereoscopic display method and apparatus using a vibration grating.
  • the naked eye stereo display technology has developed rapidly in recent years. Stereoscopic display has been favored by people because of its large amount of information and good visual effects. It has broad application prospects in 3D movies, 3D TV, industrial detection, medical inspection, aerospace technology, entertainment performance and so on.
  • the naked-eye stereoscopic display technology can provide people with more freedom and better visual experience, especially for young children and patients, because it does not require viewers to wear any auxiliary visual aids than traditional stereoscopic display technologies that require auxiliary visual aids. This is especially true for viewers with nearsightedness.
  • the raster naked-eye stereoscopic display technology utilizes parallax between the left and right eyes to achieve stereoscopic imaging.
  • the specific method is: placing a special grating on the two-dimensional flat panel display, and then using the grating to transmit the left and right eye images, the occlusion characteristics and the stereoscopic characteristics of the human, and projecting the left eye viewpoint image to the viewer's left eye.
  • the right eye viewpoint image is projected to the viewer's right eye, thereby giving the viewer a stereoscopic feeling.
  • a grating is a material made by printing or pressing technology that is attached to or outside the screen or screen to enable a person to see a stereoscopic image or a stereoscopic video using the principle of binocular parallax fusion.
  • the gratings used for autostereoscopic display can be divided into three categories: slit gratings (commonly known as black gratings), prism mirror gratings (commonly known as white gratings), and dot matrix gratings.
  • the two-view naked-eye stereoscopic display Since the two-view naked-eye stereoscopic display has the disadvantage of small stereoscopic viewing zone, it is usually used on a smaller-sized screen, such as on a mobile phone screen that is only viewable by one person. In order to obtain a larger stereoscopic viewing zone in front of a large-sized screen, it is common practice to change the dual-view stereoscopic display into a multi-view stereoscopic display, such as 5, 8 or 9 viewpoints and the like.
  • a stereoscopic image (the term "image” here includes both a still image and a video image, the same behind) is composed of two images, that is, two viewpoint images, which are customarily used.
  • the images are referred to as a left eye image and a right eye image, respectively.
  • a left eye image and a right eye image When displaying, use the half pixel on the display to display the left eye image and the other half to display the right eye image. Since there are only two viewpoints, the direction and position of the viewing are fixed, and the area where the viewer can form a stereoscopic effect (stereoscopic viewing zone) is very narrow and discontinuous, once the person's head moves slightly, or changes the viewing. The position, or change of the viewing direction, the stereoscopic feeling may disappear immediately, and the reverse parallax occurs.
  • multi-view autostereoscopic display technology is generally adopted on a large-sized naked-eye stereoscopic display device.
  • Multi-view naked-eye stereo display takes into account both binocular parallax and motion parallax.
  • the stitching combination of multiple viewpoints multiple viewers can simultaneously enjoy stereoscopic images from different positions and angles; and can make a viewer When moving within a certain range in the effective viewable area, you can still enjoy a stereoscopic image.
  • the multi-view naked-eye stereoscopic display technology causes a large decrease in stereo image resolution, and there is still a problem that the stereoscopic viewing zone is discontinuous.
  • the composite image is composed of 8 images with slightly different parallax, and the resolution of the stereo image is 1/8 of the resolution of the 2D display. If you place the grating obliquely, you can The loss of the resolution of the stereo image in the horizontal direction is assigned to the vertical direction, the horizontal resolution of the stereo image is 3 / of the horizontal resolution of the screen image, and the vertical resolution of the stereo image is 1 / 3 of the vertical resolution H of the screen image.
  • the multi-view naked-eye stereo display is in exchange for the resolution of the stereoscopic image in exchange for a larger stereoscopic viewing zone range, that is, the current multi-view naked-eye stereoscopic display technology cannot balance both high resolution and large The demand for stereoscopic viewing areas.
  • the multi-view naked-eye stereoscopic display can provide viewers with greater viewing freedom than the dual-view stereoscopic display, the stereoscopic viewing area provided to the viewer is still discontinuous, that is, when the viewer's position is moved. , will see pseudo-stereoscopic images in some areas. Summary of the invention
  • the object of the present invention is: to increase the stereoscopic viewing zone range until the viewing zone is not maintained while maintaining the stereo image resolution and the dual-view naked-eye stereoscopic image resolution.
  • the limitation of the system is to meet the dual needs of a large stereoscopic viewing zone or a stereoscopic viewing zone and a high resolution display of stereoscopic images.
  • the technical solution adopted by the present invention is to adopt a naked eye stereoscopic display method based on a vibration grating, comprising the following steps:
  • a pixel unit is a sub-pixel, or a pixel, or a plurality of sub-pixels, or a plurality of pixels;
  • step 2) Make a grating and place it in front of or behind the 2D display screen for use with the synthesized stereo image; 3)
  • the grating structure obtained in step 2) is horizontal, oblique, and vertical at a certain speed. Vibrate, or vibrate according to a specially designed vibration curve or in sub-pixels, or in pixels, or in multiple pixels, or in multiple sub-pixels;
  • the two-view composite image changes with the structure of the vibration grating, the vibration direction and the vibration law, that is, the composite image corresponding to each viewpoint position is alternately displayed in the 2D display.
  • the two-view stereoscopic composite image rearranges the 2D images of the left and right eye images in a vertical direction, following the principle of alternating arrangement, the alternating period is the same as the alternating period of the grating; for the oblique grating, the stereoscopic composite image
  • the source image used is still the left and right eye images, but the direction and angle of the arrangement are the same as the tilt angle of the raster.
  • the image rearrangement follows the principle that the left and right viewpoints are alternately arranged, and the alternating period is the same as the alternating period of the grating.
  • J is the viewing distance of the naked-eye stereoscopic display
  • ⁇ is the distance between adjacent viewing viewpoints, which is a 2D display.
  • the material poured in the vibration grating is a fast liquid crystal.
  • a naked eye stereoscopic display device based on a vibration grating comprising:
  • a two-dimensional display for displaying a two-viewpoint image or a two-viewpoint video image
  • the grating Mounting the grating in front of and behind the 2D display screen, the grating is placed vertically or tilted;
  • the grating structure vibrates at a certain speed or in a horizontal direction, or in an oblique direction, or in a vertical direction, or vibrates in units of sub-pixels, pixels, or pixel units according to a specially designed vibration curve, where the grating vibration refers to Changes in the grating structure.
  • J is the viewing distance of the naked-eye stereoscopic display
  • ⁇ is the distance between adjacent viewing viewpoints, which is the width of the pixel or sub-pixel on the 2D display screen.
  • the two-viewpoint image or the two-viewpoint video displayed on the screen of the two-dimensional flat panel display changes with the structure of the vibration grating, the direction of vibration, and the vibration law, that is, the composite image corresponding to each viewpoint position is alternately displayed in the 2D display.
  • the grating can be a prism mirror grating, or a slit grating, or a lattice grating. Compared with the prior art, the technical features and effects of the present invention:
  • the invention can be applied to a display terminal of any size, can expand the viewing range of the naked-eye stereoscopic image under the premise of ensuring the resolution of the stereoscopic image of the two-viewpoint, and can well solve the stereoscopic display resolution and the stereoscopic stereoscopic display in the multi-view naked-eye stereoscopic display. Watch the contradiction between the viewing zones.
  • the technology involved in the present invention can replace various stereoscopic display terminals that are widely popular on the market and need to wear glasses, and can also replace various multi-view naked-eye stereoscopic display terminals, including stereoscopic monitors, stereoscopic displays, stereoscopic televisions, Stereoscopic mobile phones, etc., enable viewers to see naked-eye stereoscopic programs with high definition and get rid of the dilemma of having to wear glasses to watch stereoscopic programs.
  • all kinds of dual-view stereoscopic program resources currently available on the market including stereoscopic video, stereoscopic television and other stereoscopic image resources, can be used without modification in the naked-eye stereoscopic display terminal proposed by the present invention. on.
  • FIG. 1 is a schematic diagram of a naked-eye stereoscopic display device (a) a naked-eye stereoscopic display device based on an oblique slit grating (b) a naked-eye stereoscopic display device based on a vertical slit grating (c) a naked-eye stereoscopic display device based on a tilted prism mirror grating (d) Open-hole stereoscopic display device based on vertical prism mirror grating
  • FIG 2 Schematic diagram of a two-view stereoscopic composite image.
  • Figure 3 shows the viewer at different viewing positions. In the figure, (a) when the viewer is at position 1; (b) when the viewer is at position 2. Concrete real
  • the vibration grating device proposed by the invention is a grating capable of rapidly transforming the grating structure, and the grating structure displayed by vibration of each time slot enables the left and right eyes of the viewer to respectively see the stereoscopic composite image from the two viewpoints on the display screen.
  • the left eye image and the right eye image are provided.
  • the stereoscopic image of the spatial vibration and discontinuity is used to provide the viewer with a true and continuous stereo image by using the persistence characteristics of the human eye vision and the human stereoscopic visual characteristics.
  • the viewer feels the stereoscopic effect provided by the dual viewpoint image without being restricted by the viewing zone in front of the stereoscopic display screen.
  • the present invention uses a fast liquid crystal to fabricate a vibration grating, which is implemented by the following technical solutions: 1.
  • the structure of the device used is as shown in FIG.
  • the displayed stereoscopic image is a two-view composite image.
  • a two-view stereoscopic composite image is produced by a stereoscopic image synthesis method based on a pixel unit (one pixel unit may be a plurality of pixels or a plurality of sub-pixels, or may be one pixel or one sub-pixel, the same behind), and the two-viewpoint image is horizontally
  • the image of the two viewpoints having a certain visual difference in the direction is composed of the left and right eye images, thereby ensuring that the stereoscopic image can be presented to the viewer at a higher resolution, as shown in FIG.
  • the stereoscopic composite image changes in accordance with the vibration of the grating to provide the viewer with the best stereoscopic image.
  • the two-view stereoscopic composite image is to rearrange the 2D images of the left and right eye images in a vertical direction, following the principle of alternating arrangement, the alternating period is the same as the alternating period of the grating, and the composite image is as shown in FIG. .
  • Each of the rectangles represents a pixel unit, and the number indicated indicates which viewpoint image the luminance value displayed by the pixel unit belongs to, 1 indicates a left eye image, and 2 indicates a right eye image.
  • the source image used for the stereoscopic composite image is still the left and right eye images, but the direction and angle of the arrangement are the same as the inclination angle of the grating.
  • the image rearrangement follows the principle that the left and right viewpoints are alternately arranged, and the alternating period alternates with the grating. The cycle is the same.
  • the grating structure is designed by using the grating design principle in the naked eye free stereo display technology. Therefore, the pitch, duty ratio and the like of the grating are determined to be used in conjunction with the composite image obtained in the first step, so that the viewer can obtain a stereoscopic feeling. Make a raster and place it in front of or behind the 2D display screen for use with the composite stereo image.
  • the structure of the display screen is shown in Figure 2.
  • the opening width J W of the grating, the period ⁇ and the distance D between the grating and the 2D display are the same as those of the typical two-view stereoscopic display, which satisfies:
  • J is the viewing distance of the naked-eye stereoscopic display
  • ⁇ is the distance between adjacent viewing viewpoints, which is the width of the pixel or sub-pixel on the 2D display screen.
  • the grating obtained in the third step is vibrated at a certain speed or in a horizontal direction, or in an oblique direction, or in a vertical direction, or in units of sub-pixels, pixels, or pixel units according to a specially designed vibration curve. Vibration, from The viewers in different positions can obtain stereoscopic feelings in different time slots, as shown in FIG. For example, when the viewer's left eye is located in the first viewpoint area and the right eye is located in the second viewpoint area, the stereoscopic sensation can be obtained from the above-described dual-view composite image by the grating structure of the first time slot, as shown in FIG. 3(a); The viewer's left eye is located in the second viewpoint area, and the right eye is located in the first viewpoint area.
  • the raster structure displayed by the second time slot can obtain a stereoscopic feeling from the above-described dual viewpoint composite image, as shown in FIG. 3(b). 5.
  • the grating structure in step (4) is realized at a certain speed or in a horizontal direction, or in an oblique direction, or in a vertical direction. Vibration up, or vibrate in units of sub-pixels, pixels, or pixel units according to a specially designed vibration curve.
  • the material impregnated in the vibrating grating is a fast liquid crystal, so that the grating can display the changed specific structure quickly and alternately.
  • the viewer can ensure that the stereoscopic image can be viewed at any position in front of the screen, thereby eliminating the viewing position, viewing direction and viewing area of the viewer.
  • the limitation is that the viewer can not see the pseudo stereoscopic image.
  • the vibration frequency of the vibration grating is greater than 50 Hz, that is, when the variation speed of the grating structure reaches 50 times per second or more, the human eye can feel a relatively stable stereoscopic image.
  • the stereoscopic composite image displayed in the 2D display changes with the change of the grating structure to reduce the flickering feeling caused by the change of the grating, so that the viewer can obtain a stable stereoscopic image at each position.
  • the composite image corresponding to each viewpoint position is alternately displayed in the 2D display to ensure that the viewer can see the stereoscopic image at any position in front of the screen, and the viewing position and the viewing area in the autostereoscopic display are significantly eliminated.
  • the limitation is that the viewer will not see the pseudo stereo image.
  • the present invention is applicable to a stereoscopic display technology based on a slit grating (commonly known as a black grating), a prism mirror grating (commonly known as a white grating), and a dot matrix grating.
  • the present invention uses a fast liquid crystal to fabricate a vibration grating, which is implemented by the following technical solutions: 1.
  • a dual-view composite image is produced according to the size of the display device used and the tilt angle of the grating.
  • the composite image is composed of a two-view image, that is, a left-right and right-eye image.
  • the grating can be a prism mirror grating, a slit grating, or a dot matrix grating.
  • the grating obtained in the second step is vibrated at a certain speed or horizontally, or vertically, or in an oblique direction, or is vibrated in a sub-pixel, a pixel or a pixel unit according to a specially designed vibration curve, thereby Viewers in different locations can see stereo images through different rasters in the time slot. For example, when the viewer's left eye is located in the first viewpoint area and the right eye is located in the second viewpoint area, the stereoscopic vision can be perceived by the dual-view composite image through the grating structure of the first time slot, as shown in FIG.
  • the raster structure displayed by the second time slot can sense stereoscopic vision from the above-described two-view composite image, as shown in FIG. 3(b). Vibration grating The movement, at each position, the viewer can view the corresponding two-view composite image through the raster in the time slot corresponding to the position, and clearly perceive the stereo image.
  • the liquid crystal material impregnated in the vibration grating is a fast liquid crystal, so that the grating can rapidly and alternately transform the grating structure.
  • the grating vibration changes fast enough the viewer can view stereoscopic images or stereoscopic video at any position in the specified area, significantly eliminating the limitation of viewing position and viewing area in the autostereoscopic display, and ensuring that the viewer does not You will see a pseudo stereo image.
  • the stereoscopic composite image is reasonably adjusted to minimize the flickering caused by the grating vibration.

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Abstract

一种基于振动光栅的裸眼立体显示方法与装置，涉及裸眼三维立体显示技术领域，为满足大立体观看视区或无立体观看视区限制与立体图像高分辨率显示的双重需求，采用基于振动光栅的裸眼立体显示方法，包括下列步骤：1）利用基于像素单元的立体图像合成方法制作双视点立体合成图像；2）制作光栅，并将其安置在2D显示屏幕的前面或后面；3）将步骤2）中得到的光栅结构按照一定的速度在水平方向、倾斜方向、垂直方向上振动，或者按照专门设计的振动曲线或以子像素，或以像素，或以多个像素，或以多个子像素为基本单位进行振动；4）双视点合成图像随振动光栅结构、振动方向和振动规律的变化而变化。

Description

某于振动光栅的襯眼立体 ¾示方法与装置
技术领域
本发明涉及裸眼三维立体显示技术领域， 特别涉及在保持立体图像高分辨率的前提下， 增大裸眼三维显示的立体观看视区的装置和原理。 具体讲， 涉及采用振动光栅的裸眼立体显 示方法与装置。 技术背景
裸眼立体显示技术近些年有了迅猛的发展。 立体显示由于具有信息量大、 视觉效果好等 特点受到人们的青睐， 在 3D电影、 3D电视、 工业探测、 医学检查、 航天技术、 娱乐表演等 方面均具有广泛的应用前景。
裸眼立体显示技术由于不需要观看者佩戴任何辅助视具， 比那些传统的、 需要佩戴辅助 视具的立体显示技术， 能够带给人们更多的自由和更好的视觉体验， 尤其对幼儿以及患有近 视眼的观众更是如此。
目前， 光栅式裸眼立体显示技术是利用左、 右眼之间的视差来实现立体成像。 具体做法 是： 将特制的光栅贴装在二维平板显示器上， 再利用光栅对左右眼图像的透过、 遮挡特点以 及人的立体视觉特性， 将左眼视点图像投射到观看者的左眼， 右眼视点图像投射到观看者的 右眼， 从而使观看者获得立体感觉。
光栅是指附着在画面或屏幕内或外面、 能够使人利用双眼视差融像原理看到立体图像或 立体视频的一种采用印刷或压制技术所制成的材料。 用于自由立体显示的光栅可以分为三大 类： 狭缝光栅 (俗称黑光栅)、 棱柱镜光栅 (俗称白光栅)、 点阵式光栅。
由于双视点裸眼立体显示存在立体观看视区小的缺点， 所以通常用在较小尺寸的屏幕上， 如用在仅供一个人观看的手机屏幕上。 为了在大尺寸的屏幕前获得较大的立体观看视区， 通 常的做法是将双视点立体显示变为多视点立体显示， 比如采用 5、 8或 9个视点等等。 当采用 双视点立体显示时， 立体图像 （这里的 "图像"一词既包括静止图像， 也包括视频图像， 后 面相同） 由两幅图像， 也就是两个视点图像构成， 在习惯上将这两幅图像分别称为左眼图像 和右眼图像。 显示时， 用显示器上的一半像素来显示左眼图像， 用另一半像素来显示右眼图 像。 由于只有两个视点，观看的方向和位置都是固定的， 能够使观看者形成立体感的区域（立 体观看视区） 非常狭小且不连续， 一旦人的头部发生轻微移动， 或改变了观看的位置， 或改 变了观看方向， 立体感可能会立即消失， 出现反视差的情况。
为了解决双视点自由立体显示技术对观看位置、 观看角度以及观看人数的限制， 在较大 尺寸的裸眼立体显示设备上通常采用多视点自由立体显示技术。 多视点裸眼立体显示兼顾了 双目视差和运动视差， 利用多个视点的拼接组合， 可以使多个观看者同时从不同位置和角度， 欣赏到具有立体感的图像； 并可使一个观看者在有效可视区域中一定范围内移动时， 仍能够 欣赏到具有立体感的图像。然而， 多视点裸眼立体显示技术会造成立体图像分辨率大幅下降， 仍然存在立体观看视区不连续的问题。 例如， 采用 8视点显示时， 合成图像由 8幅视差略有 不同的图像合成， 立体图像的分辨率为 2D显示器分辨率的 1/8。 如果将光栅倾斜放置， 可以 将立体图像在水平方向的分辨率的损失分配到垂直方向， 立体图像水平分辨率 为屏幕图像 水平分辨率 的 3/ ， 立体图像垂直分辨率 为屏幕图像垂直分辨率 H的 1 / 3。 当 = 8时， 立体图像的水平分辨率为 ^ = ， 垂直分辨率为 = ， 也就是说屏幕图像中 1/8的子像 素显示 8幅视点图像中的一幅， 这使得立体图像的分辨率大幅度降低。 相对于双视点裸眼立 体显示， 多视点裸眼立体显示是以牺牲立体图像的分辨率来换取更大的立体观看视区范围， 也就是说目前的多视点裸眼立体显示技术无法兼顾高分辨率与大立体观看区域的需求。 虽然 多视点裸眼立体显示相对于双视点立体显示能给观看者提供了更大的观看自由度， 但提供给 观看者的立体观看区域仍然是不连续的， 也就是说当观看者的位置移动时， 会在某些区域看 到伪立体图像。 发明内容
为克服现有多视点裸眼立体显示技术的不足， 本发明的宗旨是： 在保持立体图像分辨率 与双视点裸眼立体图像分辨率相同的情况下，增大立体观看视区范围直至无观看视区的限制， 满足大立体观看视区或无立体观看视区限的制与立体图像高分辨率显示的双重需求。 为此， 本发明采取的技术方案是， 采用基于振动光栅的裸眼立体显示方法， 包括下列步骤：
1 )利用基于像素单元的立体图像合成方法制作双视点立体合成图像， 双视点图像是由在 水平方向上具有一定视差异的两个视点的图像构成， 也就是由左、 右眼图像组成； 其中一个 像素单元是一个子像素， 或一个像素， 或多个子像素， 或多个像素；
2) 制作光栅， 并将其安置在 2D显示屏幕的前面或后面， 与合成的立体图像配套使用； 3 ) 将步骤 2) 中得到的光栅结构按照一定的速度在水平方向、 倾斜方向、 垂直方向上振 动， 或者按照专门设计的振动曲线或以子像素， 或以像素， 或以多个像素， 或以多个子像素 为基本单位进行振动；
4) 双视点合成图像随振动光栅结构、 振动方向和振动规律的变化而变化， 即 2D显示器 中交替显示与各个视点位置相对应的合成图像。
对于竖直光栅， 双视点立体合成图像是将左、 右眼图像的 2D图像重新排列， 方向为竖 直方向， 遵循交替排列的原则， 交替周期与光栅交替周期相同； 对于倾斜光栅， 立体合成图 像使用的源图像仍然是左、 右眼图像， 但排列的方向和角度与光栅的倾斜角度相同， 图像重 新排列遵循左、 右视点交替排列的原则， 交替周期与光栅交替周期相同。
将其安置在 2D显示屏幕的前面或后面， 与合成的立体图像配套使用具体是：
Q + Lp
― Q
Q + p
S Q + LP
其中， J表示裸眼立体显示的观看距离， ρ为相邻观看视点之间的距离， 为 2D显示 屏幕上的像素或者子像素的宽度。
振动光栅中灌注的材料是快速液晶。
基于振动光栅的裸眼立体显示装置， 包括：
二维显示器， 用于显示双视点图像或双视点视频图像；
在二维显示器屏幕前、 后贴装光栅， 光栅垂直放置或者倾斜放置；
光栅结构按照一定的速度或在水平方向、 或在倾斜方向、 或在垂直方向上振动， 或者按 照专门设计的振动曲线以子像素、 像素点或像素单元为单位进行振动， 这里的光栅振动是指 光栅结构发生的变化。
在二维显示器屏幕前、 后贴装光栅满足：
L L
D
Q + 厶.,
Q +
2QLp
L.
Q + Lp
其中， J表示裸眼立体显示的观看距离， ρ为相邻观看视点之间的距离， 为 2D显示 屏幕上的像素或者子像素的宽度。
二维平板显示器屏幕上显示的双视点图像或双视点视频随振动光栅结构、 振动方向和振 动规律的变化而变化， 即 2D显示器中交替显示与各个视点位置相对应的合成图像。
光栅可以是棱柱镜光栅， 或者是狭缝光栅， 或者是点阵式光栅。 与已有技术相比， 本发明的技术特点与效果：
本发明可应用在任意尺寸的显示终端上， 可以在保证双视点立体图像分辨率的前提下， 扩大裸眼立体图像的观看范围， 能非常好地解决多视点裸眼立体显示中立体显示分辨率与立 体观看视区之间的矛盾。 本发明所涉及的技术可替代目前市场上广为流行的、 需要佩戴眼镜 的各种立体显示终端， 也可以替代各种多视点裸眼立体显示终端， 包括立体监视器、 立体显 示器、 立体电视机、 立体手机等， 可使观看者看到清晰度高的裸眼立体节目， 并摆脱必须佩 戴眼镜才能观看立体节目的窘境。 同时， 目前市场上已有的各种双（目）视点立体节目资源， 包括立体电影、 立体电视等各种立体影像资源等， 都可以不经改动的用在本发明所提出的裸 眼立体显示终端上。 附图说明 图 1 裸眼立体显示设备结构示意图 （a) 基于倾斜狭缝光栅的裸眼立体显示设备 （b )基 于垂直狭缝光栅的裸眼立体显示设备 （c) 基于倾斜棱柱镜光栅的裸眼立体显示设备 （d) 基 于垂直棱柱镜光栅的裸眼立体显示设备
图 2 双视点立体合成图像示意图。 图 3 观看者在不同观看位置的情况。 图中， （a) 观看者位于位置 1时的情况； （b) 观 看者位于位置 2时观察的情况。 具体实 式
本发明提出的振动光栅装置， 是一种可以快速变换光栅结构的光栅， 每个时隙振动显示 的光栅结构可使观看者的左、 右眼分别在显示屏幕上看到由双视点立体合成图像提供的左眼 图像和右眼图像。 当光栅结构振动速度足够快时， 利用人眼视觉的暂留特性和人的心理立体 视觉特性， 使原本在空间上振动变化不连续的立体图像， 给观看者提供真实且连续的立体图 像， 保证观看者在立体显示器屏幕前不受视区限制的感受到由双视点图像提供的立体感。
为了实现上述目的， 本发明采用快速液晶来制作振动光栅， 采用下述技术方案来实现： 一、 采用的设备结构如图 1所示。
二、 显示的立体图像为双视点合成图像。利用基于像素单元（一个像素单元可以是多个像 素或多个子像素， 也可以是一个像素或一个子像素， 后面相同） 的立体图像合成方法制作双 视点立体合成图像， 双视点图像是由在水平方向上具有一定视差异的两个视点的图像构成， 也就是由左、 右眼图像组成， 从而保证立体图像能以较高的分辨率呈现给观看者， 如图 2所 示。 同时， 立体合成图像配合光栅的振动而发生改变， 以给观看者提供最佳的立体图像。 对 于竖直光栅， 双视点立体合成图像是将左、 右眼图像的 2D图像重新排列， 方向为竖直方向， 遵循交替排列的原则， 交替周期与光栅交替周期相同， 合成图像如图 1所示。 其中每个长方 形表示一个像素单元， 标注的数字表明该像素单元显示的亮度值属于哪个视点图像， 1表示 左眼图像， 2表示右眼图像。 对于倾斜光栅， 立体合成图像使用的源图像仍然是左、 右眼图 像， 但排列的方向和角度与光栅的倾斜角度相同， 图像重新排列遵循左、 右视点交替排列的 原则， 交替周期与光栅交替周期相同。
三、 光栅结构是利用裸眼自由立体显示技术中的光栅设计原理设计得到。由此确定出光栅 的节距、 占空比等指标， 使其与步骤一中得到的合成图像配套使用， 使观看者获得立体感。 制作光栅， 并将其安置在 2D显示屏幕的前面或后面， 与合成的立体图像配套使用。 显示屏 幕的结构如图 2所示。 光栅的开口宽度 JW， 周期 ^以及光栅与 2D显示器之间的距离 D与典 型的双视点立体显示中光栅的设计原理相同， 满足：
Q + LP
Q + LP '
S Q + LP
其中， J表示裸眼立体显示的观看距离， ρ为相邻观看视点之间的距离， 为 2D显示 屏幕上的像素或者子像素的宽度。
四、 将步骤三中得到的光栅按照一定的速度或在水平方向、或在倾斜方向、或在垂直方向 上振动， 或者按照专门设计的振动曲线以子像素、 像素点或像素单元等为单位进行振动， 从 而使不同位置的观看者均可在不同的时隙获得立体感觉， 如图 3所示。 例如当观看者左眼位 于第 1视点区， 右眼位于第 2视点区， 通过第 1个时隙的光栅结构可以由上述双视点合成图 像获得立体感觉， 如图 3 ( a) 所示； 当观看者左眼位于第 2视点区， 右眼位于第 1视点区， 通过第 2个时隙显示的光栅结构可以由上述双视点合成图像获得立体感觉， 如图 3 (b )所示。 五、 控制光栅中的每个像素单元， 或每个像素， 或每个子像素， 使其按照特定的规律进行 开或关， 从而实现光栅结构的透光或者遮光区域的变化和移动。 通过改变光栅中像素单元， 或像素， 或子像素的透光和遮光的频率和变化方向， 实现步骤 （四） 中光栅结构按照一定的 速度或在水平方向、 或在倾斜方向、 或在垂直方向上振动， 或者按照专门设计的振动曲线以 子像素、 像素点或像素单元为单位进行振动。
六、 振动光栅中灌注的材料为快速液晶， 从而使得光栅能够快速、交替显示变化的特定结 构。 只要光栅结构的变化速度足够快， 并结合人的心理立体视觉特性， 就可以保证观看者在 屏幕前的任意位置都可以观看到立体图像， 从而消除对观看者的观看位置、 观看方向以及观 看区域的限制， 并且能保证观看者看不到伪立体图像。
七、 振动光栅的振动频率大于 50Hz时， 也就是当光栅结构的变化速度达到每秒 50次及 以上时， 人眼可以感受到较为稳定的立体图像。
八、 2D显示器中显示的立体合成图像随光栅结构的变化而变化， 以减少光栅的变化引起 的闪烁感， 从而使得观看者在每个位置均可获得到稳定的立体图像。 基于当前显示的光栅结 构， 2D显示器中交替显示与各个视点位置相对应的合成图像， 以保证观看者在屏幕前面任何 位置都能看到立体图像， 显著消除对自由立体显示中观看位置和观看区域的限制， 且保证观 看者不会看到伪立体图像。
九、 将屏幕中显示的静止的双视点图片、图像用双视点的视频代替。调整光栅的振动速度， 使光栅的振动速度与视频播放的参数相协调， 使其满足显示立体视频的需求。
本发明适用于基于狭缝光栅 (俗称黑光栅)、 棱柱镜光栅 (俗称白光栅)和点阵式光栅的自由 立体显示技术。
为了实现上述目的， 本发明采用快速液晶来制作振动光栅， 采用下述技术方案来实现： 一、 根据采用的显示设备尺寸以及光栅的倾斜角度来制作双视点合成图像。 其中该合 成图像由双视点图像组成， 也就是由左、 右眼图像组成。
二、 利用光栅设计原理设计一种光栅结构， 确定出光栅的节距、 占空比等指标， 这里 的光栅可以是棱柱镜光栅， 也可以是狭缝光栅， 还可以是点阵式光栅。 光栅设计成功并贴装 在显示终端上之后， 使其与步骤一中得到的立体合成图像相配合， 从而使观看者感受到最佳 的立体图像。
三、 将步骤二中得到的光栅按照一定的速度或在水平、 或在垂直、 或在倾斜方向上振 动， 或者按照专门设计的振动曲线以子像素、 像素点或像素单元等进行振动， 从而使不同位 置的观看者均可透过光栅在不同时隙看到立体图像。 例如当观看者左眼位于第 1视点区， 右 眼位于第 2视点区，通过第 1个时隙的光栅结构可以由上述双视点合成图像感受到立体视觉， 如图 3 ( a) 所示； 当观看者左眼位于第 2视点区， 右眼位于第 1视点区， 通过第 2个时隙显 示的光栅结构可以由上述双视点合成图像感受到立体视觉， 如图 3 (b ) 所示。 随着振动光栅 的移动， 在各个位置上观看者均能在与其位置对应的时隙， 透过光栅观看相应的双视点合成 图像， 清晰地感受到立体图像。
四、 在发明中， 振动光栅中灌注的液晶材料是快速液晶， 从而使光栅可以快速、 交替 地变换光栅结构。 只要光栅振动变化的速度足够快， 就可以保证观看者在规定区域的任何位 置都能观看到立体图像或立体视频，显著消除对自由立体显示中观看位置和观看区域的限制， 且保证观看者不会看到伪立体图像。
五、 将屏幕中显示的静止的双视点图片、 图像用双视点的视频代替。 调整光栅的振动 速度， 使光栅的振动速度与视频播放的参数相协调， 使其满足显示立体视频的需求。 振动光 栅的振动频率大于或等于 50Hz时， 也就是当光栅结构的变化速度达到每秒 50次及以上时， 观看者可以看到较为稳定的立体图像。
六、 根据光栅变化的频率， 合理地调整立体合成图像， 使光栅振动引起的闪烁感降到 最小。

Claims

权 利 要 求 一种基于振动光栅的裸眼立体显示方法， 其特征是， 包括下列步骤：
1 ) 利用基于像素单元的立体图像合成方法制作双视点立体合成图像， 双视点图像是 由在水平方向上具有一定视差异的两个视点的图像构成， 也就是由左、 右眼图像组成； 其 中一个像素单元是一个子像素， 或一个像素， 或多个子像素， 或多个像素；
2)制作光栅，并将其安置在 2D显示屏幕的前面或后面，与合成的立体图像配套使用；
3 )将步骤 2) 中得到的光栅结构按照一定的速度在水平方向、 倾斜方向、 垂直方向上 振动， 或者按照专门设计的振动曲线或以子像素， 或以像素， 或以多个像素， 或以多个子 像素为基本单位进行振动；
4)双视点合成图像随振动光栅结构、振动方向和振动规律的变化而变化， 即 2D显示 器中交替显示与各个视点位置相对应的合成图像。
如权利要求 1所述的基于振动光栅的裸眼立体显示方法， 其特征是， 对于竖直光栅， 双视 点立体合成图像是将左、 右眼图像的 2D图像重新排列， 方向为竖直方向， 遵循交替排列 的原则， 交替周期与光栅交替周期相同； 对于倾斜光栅， 立体合成图像使用的源图像仍然 是左、 右眼图像， 但排列的方向和角度与光栅的倾斜角度相同， 图像重新排列遵循左、右 视点交替排列的原则， 交替周期与光栅交替周期相同。
如权利要求 1所述的基于振动光栅的裸眼立体显示方法， 其特征是， 将其安置在 2D显示 屏幕的前面或后面， 与合成的立体图像配套使用具体是：
Q + LP
Q + LV
S Q + LP
其中， J表示裸眼立体显示的观看距离， ρ为相邻观看视点之间的距离， 为 2D显 示屏幕上的像素或者子像素的宽度。
4、 一种基于振动光栅的裸眼立体显示装置， 其特征是， 包括：
二维显示器， 用于显示双视点图像或双视点视频图像；
在二维显示器屏幕前、 后贴装光栅， 光栅垂直放置或者倾斜放置；
光栅结构按照一定的速度或在水平方向、 或在倾斜方向、 或在垂直方向上振动， 或者按照 专门设计的振动曲线以子像素、 像素点或像素单元为单位进行振动， 这里的光栅振动是指 光栅结构发生的变化。
5、 如权利要求 4所述的基于振动光栅的裸眼立体显示装置，其特征是，在二维显示器屏幕前、 后贴装光栅满足： Q + LP
Q + P
S Q + LP
其中， J表示裸眼立体显示的观看距离， ρ为相邻观看视点之间的距离， 为 2D显 示屏幕上的像素或者子像素的宽度。
、 如权利要求 4所述的基于振动光栅的裸眼立体显示装置， 其特征是， 二维平板显示器屏幕 上显示的双视点图像或双视点视频随振动光栅结构、 振动方向和振动规律的变化而变化， 即 2D显示器中交替显示与各个视点位置相对应的合成图像。
、 如权利要求 4所述的基于振动光栅的裸眼立体显示装置， 其特征是， 光栅是棱柱镜光栅， 或者是狭缝光栅， 或者是点阵式光栅。
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