JP4404311B2 - Multi-view directional display - Google Patents

Description

  The present invention relates to a multi-view directional display. Such directional displays can display two or more images simultaneously, with each image displayed in a different direction. The invention further relates to a dual view display and autostereoscopic display incorporating a multi-view directional display.

  The general principle of the multi-view directional display is described in Non-Patent Document 1, and is shown in FIG. 1 which is a schematic partial plan view of a conventional multi-view directional display 1. The display 1 in FIG. 1 includes an image display device 2 and a parallax optical element 3. The image display device 2 includes a pixelated image display layer 4 disposed between a first light transmissive substrate 5 and a second light transmissive substrate 6. This pixelated display layer 4 can be, for example, a liquid crystal layer and can be addressed by any conventional technique for displaying two or more interlaced images. FIG. 1 shows two images displayed on the display layer 4 and the two images are displayed in alternating columns of pixels. One image is displayed on the pixel columns C1, C3, C5, and the second image is displayed on the pixel columns C2, C4, C6. (The pixel column extends toward the plane of the paper.) The image display device is illuminated by light 7 from a light source (not shown). The light source can be any suitable light source, such as, for example, a diffusion source with low spatial coherence. Components 8 and 9 are linear polarizers.

  The parallax optical element 3 of the multi-view directional display 1 separates two or more images displayed on the image display layer 4 so that each image is displayed in a different direction. In FIG. 1, the parallax optical element is formed by a parallax barrier including a plurality of transparent slits 10 separated by an opaque region 11. The transparent slit 10 extends parallel to the column of pixels (thus extending perpendicular to the page of FIG. 1). The parallax barrier may be mounted on the transparent substrate 12 and provide physical support.

  The two observation windows 13 and 14 are set as shown in FIG. 1 based on the image separation effect of the parallax barrier. In the first observation window 13, images displayed on the pixel columns C1, C3, and C5 are visible, but images displayed on the pixel columns C2, C4, and C6 are invisible. This is because the opaque region 11 of the parallax barrier blocks light from passing through the pixel column in the direction of the first observation window. Conversely, in the second observation window 14, the images displayed on the pixel columns C2, C4, and C6 are visible, but the images displayed on the pixel columns C1, C3, and C5 are invisible. This is because the opaque region 11 of the parallax barrier 3 blocks light from passing through the pixel column in the direction of the second observation window.

  FIG. 1 shows a multi-view directional display incorporated in an autostereoscopic display. In use, the observer is positioned such that the right eye coincides with the second observation window 14 and the left eye coincides with the first observation window 13. Accordingly, in FIG. 1, the observation windows are called “right observation window” and “left observation window”. The stereoscopic image pair is displayed on the image display device 1, the right eye image is displayed on the pixel columns C2, C4, and C6, and the left eye image is displayed on the pixels C1, C3, and C5. . Therefore, an observer who positions the left eye and the right eye so as to coincide with the left observation window and the right observation window, respectively, sees the image for the left eye with the left eye and the image for the right eye with the right eye. Perceive an image.

  The parallax optical element of the display 1 in FIG. 1 is a parallax barrier composed of transparent strips separated by opaque regions. Other types of parallax optical elements are also known. For example, it is also known to use a lenticular array as a parallax optic, which typically directs images from different regions of the pixelated image display layer 4 in different directions, thereby directing them. A columnar lens that functions to acquire the sexual effect is provided.

  A multi-view directional display may alternatively be incorporated into a “dual view” display. Dual view displays are intended to display one image to one viewer and another image to another viewer. For example, a dual view display in a car may display a map to the driver of the car and display a television program or movie to the passengers. The principle of the dual view display is generally the same as the principle of the autostereoscopic display, but the two images displayed on the image display layer of the dual view display are the images for the left eye and the right eye of the stereoscopic image pair. It is not an independent image. In addition, the two images displayed by the dual view display are intended to be viewed by different observers, and the viewing angle separation V (this is the angle between the center of the viewing window of the two images). (Separation) requires that the dual view display be larger than the autostereoscopic display for a given viewing distance.

The viewing angle separation V is the angular separation between the centers of the two image viewing windows, and thus the angle at which the viewer needs to be moved in order to move between two different views on the display. For a multi-view display having a parallax barrier as a parallax optical element, the observation angle separation V expressed in radians is V = np / s (1)
Where n is the refractive index of the material that separates the parallax barrier 3 and the image display layer 4 (in FIG. 1, n is the refractive index of the rear transparent substrate 5 of the image display device). ), P is the pixel pitch of the image display layer, and s is the separation distance between the parallax barrier 3 and the image display layer 4. For a given image quality (resolution), the pixel pitch p is usually fixed. The substrate of the directional display 1 is usually made of glass, and the refractive index n of the glass usually has little difference for most commercially available glasses.

  One approach to expand the viewing angle separation is to reduce the thickness of the rear substrate 5 of the image display device, thereby reducing the separation between the parallax optic 3 and the image display layer 4. However, the thickness of the substrate 5 has a tendency to be damaged, is difficult to manufacture and cannot provide sufficient structural support and therefore cannot be significantly reduced below 0.5 mm. Therefore, it is substantially difficult to reduce the thickness of the rear substrate 5 to a thickness that can substantially enlarge the observation angle.

  It may be desirable to reduce viewing angle separation. For example, if the display is intended to be displayed at a large viewing distance, the viewing angle separation of the display can be greater than the desired viewing angle separation. Traditionally, viewing angle separation is reduced by using a thick substrate and enlarging s, but this significantly increases the weight of the display.

  It is an object of the present invention to provide a multi-view directional display that enlarges or reduces the observation angle separation by using an imaging unit that images a parallax optical element or an image display panel.

According to the present invention, a multi-view directional display comprising a parallax optical element (3), a pixelated image display layer (4), one image of the parallax optical element and the image display layer, and the parallax The parallax optical element (3) and the image display so that the separation distance between the optical element and the other of the image display layer is smaller than the separation distance between the parallax optical element and the image display layer. Imaging means (29; 29 ′; 39; 43, 44, which images the one of the layers (4), thereby expanding the angular separation between the two observation windows (13, 14) generated by the display. 45; 47, 48; 61) and a first tracking means for determining the distance between the display and the viewer, and the lateral direction of the viewer relative to the display A first control for controlling the focal length of the imaging means in accordance with the distance determined by the first tracking means; and at least one tracking means (41) of the second tracking means for determining the position A multi-view directional display that performs at least one of the second control for controlling the lateral position of the imaging means according to the lateral position of the observer determined by the second tracking means This achieves the above objective.

According to the present invention, a multi-view directional display includes a parallax optical element (3), a pixelated image display layer (4), an image (30, 30 ′) of the parallax optical element (3), and the The parallax optical element (3) so that the separation distance from the image display layer (4) is smaller or larger than the separation distance between the parallax optical element (3) and the image display layer (4). Imaging means (29; 29 ′; 39; 43, 44, 45; 47), respectively, thereby enlarging or reducing the angular separation between the two observation windows (13, 14) generated by the display. , 48; and 61), the second you want to determine that the display first tracking means for determining the distance between the observer and the lateral position of the observer relative to the display A first control unit for controlling a focal length of the imaging unit according to a distance determined by the first tracking unit, and a lateral position of the imaging unit. There is provided a multi-view directional display that performs at least one of the second controls that are controlled in accordance with the lateral position of the observer determined by the second tracking means , thereby achieving the above-described object. The

  The imaging means may be configured to generate an image of the parallax optical element or image display layer having a pitch substantially equal to the pitch of the parallax optical element or image display layer.

  The parallax optical element (3) is arranged behind the image display layer (4), the imaging means is arranged between the parallax optical element (3) and the image display layer (4), and In use, an image (30, 30 ′) of the parallax optic (3) may be formed.

  The image display layer (4) is disposed behind the parallax optical element (3), the imaging means is disposed between the image display layer (4) and the parallax optical element (3), and In use, an image of the image display layer can be formed.

  The imaging means is configured to generate an image of an element of the parallax optical element or a pixel of the image display layer having a width substantially equal to a width of the element of the parallax optical element or the pixel of the image display layer. obtain.

  The imaging means may be configured to generate an image of the parallax optical element element or the image display layer pixel having a width greater than the parallax optical element element or the image display layer pixel width.

  The imaging means generates an image of the elements of the parallax optic or pixels of the image display layer having a width that is substantially an integer multiple of the width of the elements of the parallax optic or pixels of the image display layer. Can be configured.

  The imaging means may be configured to generate an image of a parallax optic element or an element of the parallax optic element having a width smaller than a width of the image display layer or a pixel of the image display layer.

  The imaging means outputs an image of the parallax optic element or the image display layer pixel having a width substantially equal to the width of the parallax optic element or the image display layer pixel divided by the integer. May be configured to generate.

  It may further comprise blocking means for blocking an image of one or more elements of the parallax optic.

  The blocking unit may include a plurality of opaque regions extending between the imaging unit and one of the parallax optical element and the image display layer.

  A diffuser layer may be provided that is positioned to substantially coincide with an image plane of the parallax optical element or an image plane of the image display layer.

  The imaging means may have a variable focal length.

  There may be a controller for controlling the focal length of the imaging means.

  A first tracking means for determining a distance between the display and the observer, wherein the controller receives an output from the tracking means during use, whereby the display and the observer; The focal length of the imaging means may be controlled based on the distance between the imaging means.

  The imaging means may have a variable focal length and a variable magnification.

  There may be a controller for controlling the focal length and magnification of the imaging means.

  A diffuser layer may further be provided.

  The imaging means may comprise a lens array.

  The imaging means comprises first and second disabling lens arrays, the first lens array being offset laterally with respect to the second lens array, the display comprising: A controller may be provided for enabling the first lens array or the second lens array while disabling the other of the first and second lens arrays.

  The imaging means may be movable laterally with respect to one of the parallax optical element and the image display layer.

  Second tracking means may be provided for determining the lateral position of the viewer relative to the display.

  A second tracking means is provided for determining an observer's lateral position relative to the display, and the controller may receive an output from the second tracking means during use.

  A second tracking means for determining a lateral position of an observer with respect to the display, wherein the lateral position of the imaging means with respect to one of the parallax optical element and the image display layer is the second position; Based on the output from the tracking means.

  Means may further be provided for identifying an observer of the display.

  The imaging means may be fixed with respect to one of the parallax optical element and the image display layer and movable with respect to the other of the parallax optical element and the image display layer.

  The imaging means generates an image of the parallax optic or image display layer that is laterally offset with respect to the image display layer or the parallax optic, whereby the display is in first use. And the second image, wherein the angular spread of the first image is different from the angular spread of the second image, and is configured to display the first image and the second image. obtain.

  Said imaging means may be asymmetric imaging means.

  Each element of the imaging means may comprise a first portion having a first focal length and a second portion having a second focal length different from the first focal length.

  The imaging means may be configured such that the image of the parallax optical element or the image display layer is a virtual image.

  The parallax optical element or the image display layer may generate an image of the parallax optical element or the image display layer having a non-uniform pitch in cooperation with the imaging unit.

  The parallax optical element or the image display layer is linked with the imaging means, and the parallax optical element or the image display layer displays an image of the parallax optical element or the image display layer with respect to the parallax optical element or the image display layer. It can be produced on the other side of the layer.

  The parallax optical element or the image display layer may cooperate with the imaging layer to generate an image of the parallax optical element or the image display layer outside the display.

  A first aspect of the present invention provides a multi-view directional display comprising a parallax optical element, a pixelated image display layer, and an imaging means, the imaging means comprising a parallax optical element and an image display layer. One is imaged so that the separation between one image of the parallax optical element and the image display layer and the other of the parallax optical element and the image display layer is greater than the separation between the parallax optical element and the image display layer. This also increases the angular separation between the two viewing windows generated by the display.

  In the display of the present invention, the observation angle separation is determined by the distance between one image of the parallax optical element and the image display layer and the other of the parallax optical element and the image display layer that are not imaged. By making this distance smaller than the separation between the parallax optical element and the image display layer, the observation angle separation can be expanded. The present invention does not require that the thickness of any of the substrates of the display be reduced, so that thicker and structurally robust substrates can be used.

  There are a number of prior art displays that incorporate imaging means. However, in any of the prior art displays, no imaging means for imaging the parallax optic or the image display panel has been used to increase the viewing angle separation.

  General prior art on lenses in directional displays (eg, the above description by Starkes et al.) Describes lenticular systems in which the lens itself is used as an image splitter. In other words, the lens is described as separating the view and imaging multiple sets of pixels into multiple windows. Thus, the feature of this lens array is to re-image the pixels in a plane at the position of the viewer's eye.

  FIG. 2A is a schematic view of a prior art directional display 15 described in European Patent Application 0 597 629 and incorporating imaging means LS1. In this conventional display, two interlaced images are displayed on a pixelated display panel 16, and the images are separated by a parallax optical element LS2. The display is illuminated by a switching illuminator 18 and the light from the illuminator is focused on the diffuser 17 by the imaging means LS1 and modulated by the pixelated display panel 16 as this light passes from the imaging means LS1 to the diffuser. Is done. Thus, in this prior art display, the imaging means LS1 produces a greatly reduced image of the switching illuminator 18 on the pixel plane. The purpose of this is to ensure that light from all points on the extended illuminator properly passes through the pixel and parallax optic LS2. The imaging means LS1 does not provide an expansion of the observation angle separation.

  FIG. 2B shows a further prior art display 15 'as described in EP 0 597 629. This generally corresponds to the display of FIG. 2A, except that a pixelated display panel 16 is placed between the switching illuminator 18 and the imaging means LS1. In this display, the imaging means LS1 re-images the illuminator on a diffuser plane that provides a full resolution 3D display with a time-series display synchronized with the exchange illuminator. The lens array LS2 is an image splitter.

  FIG. 3 shows a further prior art autostereoscopic display, as shown in EP 0 655 555. This display is illuminated by an autostereoscopic projection unit 20 having an array of movable illuminators. The image is projected onto the double lenticular screen 21. The two lenticular arrays 22, 23 of the screen 21 have different focal lengths, and the lenticular screen 21 changes the viewing angle separation of the projected image. In this prior art display, the first lenticular screen produces an image of the switching illuminator 18. Such prior art displays are only suitable for projection type displays with different display components and are not suitable for relatively small integrated “desktop” or “direct view” type displays.

  FIG. 4 is a further description of “Reduce of the Thickness of Lenticular Stereoscopic Display Using Full Color LED Panel” (Proc. SPIE Vol. 4660, page 236, 2002) by Yamamoto et al. FIG. The display 24 is an autostereoscopic display in which two lens arrays 25 and 26 are arranged in front of a very large poster-sized LED display 27. The display 27 has a large pitch and a short viewing distance and is therefore generally not suitable for use as an autostereoscopic display in large screen poster / advertisement style applications. This is because the separation between the intended (long) viewing distance views is greater than the average separation between the two human eyes. In order to reduce viewing angle separation, the first lenticular barrier 25 reduces the pixels of the display panel 27 and forms an image of the display having a much smaller pixel pitch. The second lenticular sheet 26 separates the two interlaced views displayed on the LED panel, but the viewing angle separation is small due to the reduced pixel pitch of the imaged LED panel, thereby The two images can be comfortably viewed by the viewer's left and right eyes.

  US 2002/008096 discloses a volumetric three-dimensional display using multiple light sources. Each light source is provided with light beam scanning means such as a mirror and a microlens element. The moving image of the light source generates a three-dimensional image in the space between the viewer and the display. The display does not have a pixelated image display layer.

  Park et al., “Analysis of Viewing parameters for two display methods based on integral photography” (Applied Optics Vol. 40, No. 29, 5217). A display is disclosed. This principle involves a small area on the display being imaged to the image plane between the view and the display by a lens array (one lens for each area). Integrated imaging can be thought of as a multi-view display with multiple views, where the separation between views is much smaller than that of the human eye. A lens array can be thought of as a parallax optic, but this lens focuses the pixel plane area to the image plane between the viewer and the display, not to the plane of the viewer. However, the position of this image does not affect the viewing angle of the display.

  Japanese Patent Laid-Open No. 10-206795 discloses an autostereoscopic display that uses a lenticular lens array as a parallax optical element and provides angular separation between two displayed views. The display further comprises a parallax barrier that limits the light passing through the lens array, thereby reducing crosstalk and assisting in the formation of the observation window. The barrier and lens array are in substantially the same plane. The lens array is an image splitter and the barrier reduces system crosstalk by limiting the light passing through the lens. The lens does not re-image the barrier or pixel (unless the normal lenticular images the pixel to the display plane).

  US Pat. No. 6,304,288 discloses a tracked autostereoscopic display system having two lenticular barriers, one at the front of the image display panel and the other at the rear of the image display panel. The display is illuminated by a light source array, and a lenticular barrier behind the image display panel focuses the light source elements on the pixel plane. A lenticular barrier in front of the image display panel provides angular separation between the two images displayed on the image display panel.

  U.S. Pat. No. 6,061,179 discloses a display that is switchable between a 2D display mode and a 3D display mode. In certain embodiments, the display comprises a single mask and a single lenticular barrier, and switching between display modes is performed by moving the lenticular barrier toward or away from the mask.

  U.S. Pat. No. 5,682,215 discloses a liquid crystal display panel with an in-cell lens. These are provided to improve the brightness of the display panel by redirecting light incident on opaque components such as gate or source lines. This display is not a directional display.

  EP-A-1089115 discloses a liquid crystal cell provided with an external microlens. This display is not a directional display and no microlens is provided to separate the views. Rather, the display is a reflective display for use in a projection display.

  EP 0721132 discloses that a macro-view lens and a macro-projection lens form two window regions depending on two light sources emitting different polarization states and a pixelated image display layer. An autostereoscopic display is disclosed. The image display layer is disposed between the macro viewing lens and the projection lens. The pixel image is reprojected by the lenticular screen.

  A second aspect of the present invention provides a multi-view directional display comprising a parallax optical element, a pixelated image display layer, and an imaging means, the imaging means images the parallax optical element, The separation between the image of the parallax optical element and the image display layer is made smaller or larger than the separation between the parallax optical element and the image display layer, so that the two generated by the display Enlarge or reduce the angular separation between the observation windows, respectively.

  A third aspect of the present invention provides a multi-view directional display comprising a parallax optical element, a pixelated image display layer, and an imaging means, the imaging means comprising a parallax optical element and an image display layer. One is imaged so that the image of the parallax optical element or image display layer has a pitch substantially equal to the pitch of the parallax optical element or image display layer.

  The display according to the second or third aspect of the invention can be used to reduce or enlarge the viewing angle separation. In particular, this display allows viewing angle separation to be reduced without requiring the use of a thick glass substrate for displays that are intended to be viewed remotely from the display by an observer. These aspects of the invention can also be used to expand viewing angle separation in applications where the display does not produce sufficient angular separation at a given viewing distance.

  In the display according to the third aspect, the imaging means is configured to generate an image of the parallax optic or image display layer having a pitch substantially equal to the pitch of the parallax optic or image display layer. In the prior art display 24 of FIG. 4, the pixelated display layer image pitch is deliberately made smaller than the display layer pitch to reduce viewing angle separation. However, when the image pitch (or image display layer) of the parallax optical element is significantly different from the pitch of the parallax optical element (or image display layer), the display characteristics of the display such as resolution are changed. Accordingly, it is desirable that the pitch of the image of the parallax optical element (or image display layer) is the same as or similar to the pitch of the parallax optical element (or image display layer). This is because the present invention can be implemented with minimal modification of other components of the display.

  The imaging means of the display according to the first or second aspect may be configured to generate an image of the parallax optic or image display layer having a pitch substantially equal to the pitch of the parallax optic or image display layer.

  The imaging means of the display according to the third aspect, in use, forms an image of the parallax optical element or the image display layer, whereby one image of the parallax optical element and the image display layer, and the parallax optical element and the image display layer The separation between the other of the two is smaller or larger than the separation between the parallax optic and the image display layer, thereby increasing or decreasing the angular separation between the two viewing windows generated by the display, respectively. To do.

  The parallax optical element can be behind the image display layer, and the imaging means can be disposed between the parallax optical element and the image display layer, and in use can form an image of the parallax optical element. Alternatively, the image display layer can be disposed behind the parallax optical element, and the imaging means can be disposed between the image display layer and the parallax optical element, and in use can form an image of the image display layer.

  As used herein, the terms “backward” and “frontward” refer to the order of components viewed by a person viewing the display from the intended viewing position of the display.

  The imaging means may be configured to generate an image of the parallax optic element or image display layer pixel having a width substantially equal to the width of the parallax optic element or image display layer pixel. The imaging means may be configured to generate unit magnification of the parallax optic or image display layer.

  Alternatively, the imaging means may be configured to generate an image of a parallax optic element or image display layer pixel having a width greater than the width of the parallax optic element or image display layer pixel. The imaging means may be configured to generate an image of a parallax optic element or image display layer pixel having a width that is substantially an integer multiple of a parallax optic element or image display layer pixel width. . The imaging means may be configured to generate a non-unit magnification (greater than unit magnification) of the parallax optic or image display layer.

  Alternatively, the imaging means may be configured to generate an image of the elements of the parallax optic or the pixels of the image display layer having a width smaller than the pitch of the parallax optic or image display layer. The imaging means is configured to generate an image of a parallax optic element or image display layer pixel having a width substantially equal to a width divided by an integer number of parallax optic element or image display layer pixels. Can be done. The imaging means may be arranged to generate a non-unit magnification (smaller than unit magnification or smaller than reduction magnification) of the parallax optical element or the image display layer.

  The display may comprise blocking means for blocking the image of one or more elements of the parallax optic. The blocking means can be configured, for example, to suppress the generation of the secondary observation window.

  The blocking means includes a plurality of opaque regions extending between the imaging means and one of the parallax optical element and the image display layer. The opaque region blocks the optical path between the imaging means element and the other elements of the parallax optic or image display layer, while the imaging means element forms an image of the corresponding element of the parallax optic or image display layer Make it possible to do.

  The imaging means may have a variable focal length and the display may have a controller that controls the focal length of the imaging means.

  The display can comprise a diffuser layer, which is positioned to substantially coincide with the image plane of the parallax optic or the image display layer.

  The display may further comprise a first tracking means for determining a distance between the display and the observer, and in use, the controller receives an output from the tracking means, whereby the display and the observer The focal length of the imaging means is controlled based on the distance between the two.

  The imaging means can have a variable focal length and variable magnification, and the display can have a controller for controlling the focal length and magnification of the imaging means.

  The display may further comprise a diffuser layer. To provide a display in which the image size of the elements of the parallax optic element in the diffuser or the pixel size of the image display layer can be controlled by controlling the position where the image is formed. A diffuser layer may be provided. Thereby, the effective size of the image of the element of the parallax optical element or the image of the pixel can be changed in a controllable manner.

  The imaging means may comprise a lens array.

  The imaging means may comprise a first and a second disabling lens array, the first lens array being offset laterally with respect to the second lens array, the display being a first A controller may be provided for enabling the lens array or the second lens array while disabling the other of the first and second lens arrays.

  The imaging means may be movable laterally with respect to one of the parallax optical element and the image display layer.

  The display may comprise a second tracking means for determining the position of the observer transverse to the display. In use, the controller can receive the output from the second tracking means. The lateral position of the imaging means relative to one of the parallax optic and the image display layer can be controlled based on the output from the second tracking means.

  The imaging means may be fixed with respect to one of the parallax optical element and the image display layer, and may be movable with respect to the other of the parallax optical element and the image display layer. Lateral and / or longitudinal relative motion may be possible. The relative movement may be controlled based on an observer tracking device that tracks the lateral and / or vertical movement of the observer relative to the display. In this embodiment, the position of the imaging means is fixed relative to the component being imaged. In embodiments where the imaging means images the parallax optical element, for example, the position of the image of the parallax optical element relative to the image display layer is controlled by moving the imaging means and the parallax optical element together with respect to the image display layer. obtain.

  The display may further comprise means for identifying the viewer of the display.

  The imaging means may be adjusted to produce an image of the parallax optic or image display that is laterally offset with respect to the image display layer or parallax optic, whereby the display is in first and second in use. Two images are displayed, whereby the range of angles of the first image is different from the range of angles of the second image.

  The imaging means can be an asymmetric imaging means. This is another way in which first and second images of different angular ranges can be formed.

  Each element of the imaging means may comprise a first portion having a first focal length and a second portion having a second focal length different from the first focal length. This produces two images of the parallax optic or image display layer, thus providing first and second images in different angular ranges.

  The imaging means may be configured such that the image of the parallax optical element or the image display layer is a virtual image.

  The parallax optical element or image display layer may be associated with an imaging means for generating an image of the parallax optical element or image display layer having a non-uniform pitch.

  The parallax optical element or the image display layer may be linked to an imaging means for generating an image of the parallax optical element or the image display layer on the other side of the parallax optical element or the image display layer on the side opposite to the parallax barrier and the image display layer. In a display in which the parallax barrier is behind the image display layer and the image of the parallax barrier is formed, for example, the image of the parallax barrier may be on the opposite side of the parallax barrier of the image display layer.

  The parallax optical element or the image display layer may be linked with the imaging means to generate an image of the parallax optical element or the image display layer outside the display.

  A fourth embodiment of the present invention comprises a collimated backlight, a pixelated image display layer, and an imaging means for imaging the collimated backlight at or near the image display layer A multi-view directional display comprising:

  The imaging means may image the collimated backlight substantially in the plane of the image display layer. Alternatively, the imaging means may image the backlight collimated in a plane between the backlight and the image display layer, or in a plane opposite to the backlight of the image display layer.

  The backlight may optionally operate as a collimated backlight or a non-collimated backlight. As a result, the directional display mode or the 2D display mode can be selected.

  A fifth aspect of the present invention provides an optical device comprising a light transmissive substrate having a parallax optical element associated with one surface of the substrate and a lens array associated with the other surface of the substrate. The parallax optical element may be formed on or near one surface of the substrate. The lens array can be formed on or near the other surface of the substrate. The substrate, parallax optic, and lens array can be formed as an integrated unit.

  Preferred embodiments of the present invention will now be described by way of example with reference to the accompanying drawings.

Like reference numerals refer to like components throughout the specification and drawings.
Starkes, “Int. J. Virtual Reality”, Vol. 1, no. 2, 1995

  In the display according to the first aspect of the present invention, the observation angle separation is determined by the distance between one image of the parallax optical element and the image display layer and the other of the parallax optical element and the image display layer that are not imaged. By making this distance smaller than the separation between the parallax optical element and the image display layer, the observation angle separation can be expanded. The present invention does not require that the thickness of any of the substrates of the display be reduced, so that thicker and structurally robust substrates can be used.

  The display according to the second or third aspect of the invention can be used to reduce or enlarge the viewing angle separation. In particular, this display allows viewing angle separation to be reduced without requiring the use of a thick glass substrate for displays that are intended to be viewed remotely from the display by an observer. These aspects of the invention can also be used to expand viewing angle separation in applications where the display does not produce sufficient angular separation at a given viewing distance.

  FIG. 5 is a plan sectional view of the multi-view directional display 28 according to the first embodiment of the present invention. The display 28 includes, for example, an image display including a pixelated image display layer 4 such as an active matrix TFT liquid crystal display layer disposed between the first light transmissive substrate 5 and the second light transmissive substrate 6. Device 2 is provided. The display 28 is illuminated by light 7 from a light source (not shown) located behind the display, and the image display layer can be any transmissive display layer, in this embodiment the image display layer 4 is The display device 2 comprises first and second polarizers 8, 9 arranged one on each side of the image display layer. The image display element 2 further comprises addressing means such as pixel electrodes, switching elements, etc. for addressing the pixels of the liquid crystal layer, which can be completely conventional and are therefore omitted from FIG. ing.

  The display 28 further includes a parallax optical element 3 disposed behind the image display element 2. In this embodiment, the parallax optical element 3 is a parallax barrier having a light-transmitting slit 10 separated by an opaque portion 11 extending toward the paper surface in FIG. In operation, driving means (not shown) drive the pixelated display layer 4 to display two interlaced images, which are shown in FIG. The pixel columns C1, C3, C5 are shown shaded gray and the other pixel columns C2, C4, C6 showing different images are not shaded (the pixel columns are shown in FIG. Extending towards). This is intended to show that one image is displayed on the pixel columns C1, C3, C5 and the second image is displayed on the other pixel columns C2, C4, C6. The parallax barrier 3 causes an angular separation of the two images displayed on the image display layer 4, thereby forming two observation windows as shown in FIG. The images displayed on the pixel columns C1, C3, C5 are visible in the observation window 13, and therefore this window is shaded gray. Other images displayed in the pixel columns C2, C4, C6 are visible in the right observation window 14.

  As described above, the structure of the display 28 is very similar to a conventional display.

  The parallax barrier 3 is disposed between the first light transmissive substrate 12 and the second light transmissive substrate 12 ′.

  The display device according to the present invention further includes an imaging means for forming one image of the parallax optical element 3 and the image display layer 4. Here, the present invention is applied to a rear barrier display in which the parallax optical element is arranged behind the image display element 2, and the imaging means includes the parallax optical element 3, the image display layer 4, and the like as in the case of FIG. Between the two, and forms an image of the parallax optical element 3. The imaging means is constituted by the lenticular lens array 29 in FIG. 5, which forms an image 30 of the parallax barrier 3. Each lens of the lenticular lens array 29 has a pixel column C1. . . It extends substantially parallel to C6.

  Although FIG. 5 shows a lenticular lens array as an imaging means, the present invention is not limited to this particular type of imaging means. Essentially any convergent diffraction or refractive microstructure (eg, Fresnel lens) can be used at the normal lens position. The imaging means can further be formed using holographic optical elements.

In the absence of imaging means, the viewing angle separation achieved by the display 28 of FIG. 5 is the pixel pitch p of the image display layer 4, the separation between the image display 4 and the parallax optic 3, and the image display layer 4. And the refractive index of the material separating the parallax optical element 3. According to the present invention, the image 30 of the parallax optical element is separated between the image display layer 4 and the image 30 of the parallax optical element indicated by s ′ in FIG. S ′ <s. In other words, s ′ <s. The observation angle separation in the display of FIG.
V = np / s ′ (2)
Is determined by the separation between the image 30 of the parallax optic and the image display layer, where n is the refractive index of the material separating the image display layer 4 and the image 30 of the parallax optic (and thus In FIG. 5, n is the refractive index of the substrate 5), and p is the pixel pitch of the image display 4.

  The thickness of the substrate 5 does not affect the observation angle separation given by equation (2). Accordingly, the substrate 5 is relatively thick, thereby providing sufficient structural strength.

  The position of the parallax optical element image 30 depends on the focal length of the lenses of the lenticular lens array (or more generally by the imaging power of the imaging means) and between the parallax optical element 3 and the lenticular lens array ( Or more generally, it is determined by separation between the parallax optic and the imaging means). The separation between the imaging means and the parallax optical element is determined by the thickness of the substrate 12 'separating the parallax optical element 3 and the imaging means. Thus, the image 30 of the parallax optic may be in any desired plane perpendicular to the axis of the display by selecting the imaging power of the imaging means and thus the separation between the imaging means and the parallax optic. It may be configured to be located in

  It will be appreciated that the first light transmissive substrate 12 shown in FIG. 5 is not necessary for the operation of the display and can therefore be omitted. The parallax optical element 3, the second light transmissive substrate 12 ', and the lens array 29 are preferably manufactured as an integrated unit.

  FIG. 6 shows a schematic plan cross-sectional view of a display 28 'according to a further embodiment of the present invention. This embodiment is generally similar to the embodiment of FIG. 5 and the detailed description of this embodiment will not be repeated.

  In the display of FIG. 5, the image 30 of the parallax optical element is formed on the image display layer 4 on the same side as the parallax optical element 10. Alternatively, the image 30 of the parallax optical element may be formed on the opposite side of the image display layer 4 from the parallax optical element 10, which is the case when it can be placed on the display of FIG. In fact, in the display 28 ′ of FIG. 6, the imaging power of the imaging means (configured by the lenticular lens array 29) and the thickness 12 ′, 5 of the substrate separating the parallax optical element 3 and the image display layer 4 are selected. Thus, the parallax optic image 30 is not formed in the display 28 ', but formed between the display and the viewer. The view separation in this embodiment is again determined by the separation between the parallax optic image 30 and the image display layer 4 (again denoted s').

  When it is assumed that the image 30 of the parallax optical element is arranged so that s ′ <s (where s is the distance between the image display layer 4 and the parallax optical element 3), the embodiment of FIG. The observation angle separation at is enlarged. Alternatively, the viewing angle separation in this embodiment can be reduced if the parallax optic image 30 is arranged so that s'> s. This is useful when the display is used in applications that require a large viewing distance and thus a small viewing angle separation. This is because the present invention avoids the use of a glass substrate which is very thick in the prior art.

  Note that the pixel column assignment to the two images is not the same in the two views, since the image of the parallax optic is formed on the opposite side of the image display layer in FIGS. For example, light passing through the pixel columns C1, C3, C5 shown shaded in FIG. 5 is directed toward the left viewing window 13, whereas it is shown shaded in FIG. The light passing through the pixel columns C1, C3, C5 is directed towards the right observation window 14. Accordingly, the left observation window 13 in FIG. 5 is shown with shading, whereas the right observation window 14 is shown with shading in FIG.

  In the displays of FIGS. 5 and 6, the imaging means is configured such that the pitch of the parallax optic image is equal to or substantially equal to the pitch of the parallax optic, and thus in the parallax optic image 30, The pitch b ′ between the apertures 10 ′ of the image 30 of the parallax optical element is substantially equal to the original pitch b of the parallax optical element 3. Furthermore, the width of the image of the element of the parallax optic is approximately equal to the width of the element, so in FIGS. 5 and 6, the width w ′ of the image 10 ′ of the barrier slit is the width of the transmissive slit 10 of the parallax barrier. It is almost equal to w. However, according to the present invention, the parallax optical element (or the image display layer) based on the image of the parallax optical element (or the image of the image display layer in the embodiment where the imaging means forms the image of the image display layer) is used. The display is not limited to a display that is not significantly enlarged. FIG. 7A is a plan cross-sectional view of a further display device ″ according to the present invention, where the image of the parallax optic is magnified compared to the original parallax optic (in this case, greater than 1). Has been.

  The display device 28 '' of FIG. 7A generally corresponds to the display device 28 of FIG. 5 and is therefore not described in further detail. However, in the display device 28 ″, the imaging means which is also the lenticular lens array 29 in this embodiment images the parallax optical element 3, so that the image of the element of the parallax optical element is compared with the original element. Is expanded. The magnification is achieved by using a lens array 29 having a focal length such that the distance between the parallax optical element image 30 and the lens array is greater than the distance between the parallax optical element and the lens array. The This is shown in FIG. 7A for a display where the parallax optic is a parallax barrier 3 having a transmissive slit 10 separated by an opaque region 11, although this embodiment of the present invention is a parallax optic of this particular form. It is not limited to an element.

  More specifically, the width w ′ of the image 10 ′ of the transmissive slit 10 of the parallax barrier is larger than the width w of the transmissive slit 10 in the original parallax barrier 3. However, the pitch b ′ of the parallax barrier image 30 is equal to or substantially equal to the pitch b of the original parallax barrier 3. This is because each lens segment images its specific aperture. The pitch of the lens array is preferably the same as the pitch b of the parallax barrier.

  In certain preferred embodiments, the width w ′ of the parallax barrier slit image 10 ′ is approximately equal to an integer multiple of the width w of the transmissive slit 10 of the parallax barrier 3. In FIG. 7A, the width w ′ of the transmissive slit image 10 ′ in the parallax barrier image 30 is almost twice the width w of the transmissive slit 10 in the parallax barrier 3, but any almost integral multiple is used. obtain. Making the width w ′ of the transmissive slit image 10 ′ an integral multiple of the width w of the transmissive slit 10 of the parallax barrier means that the secondary observation window 31 does not overlap the primary observation windows 13 and 14. To do. Accordingly, the observer can observe the display 28 ″ without being caught by crosstalk. By making the width w 'of the image 10' of the transmissive slit larger than the width w of the transmissive slit 10 of the parallax barrier 3, but not equal to an integral multiple thereof, crosstalk can occur. For example, in the case of an autostereoscopic display, when the secondary window formed by the image for the left eye overlaps with the primary observation window of the image for the right eye, the observer is You will experience some crosstalk as you see a mixture of images.

  However, in some applications, a non-integer magnification of the width of the transmissive slit can be used, assuming that crosstalk is kept down to an acceptable level.

  FIG. 7B is a schematic plan sectional view of a further display 28 ″. Again, this is generally similar to the display of FIGS. 5 and 7A and is therefore not described in detail.

  The imaging means of the display 28 ″ of FIG. 7B, again the lenticular lens array 29, produces an image 30 of the display parallax optic. The parallax optical element is again the parallax barrier 3. The lenticular lens array produces a parallax barrier image 30 in which the width w 'of the transmissive slit image 10' is smaller than the width w of the transmissive slit. Furthermore, the pitch of the image of the parallax barrier b ′ is smaller than the pitch b of the parallax barrier 3. That is, w '<w and b' <b, and both slit width and barrier pitch are reduced by the same amount.

  In FIG. 7B, the width w ′ of the transmissive slit image 10 of the parallax barrier 3 is about half the width w of the slit 10 of the parallax barrier 3.

  Making the width w ′ of the image 10 ′ of the transmissive slit smaller than the width w of the transmissive slit 10 of the parallax barrier means that the spatial spread of the image of the transmissive slit in the parallax barrier 3 is reduced. However, this increases the brightness of the display when the pixel width of the image display layer 4 is small, but if the slit is wider than the pixel aperture, light is lost in the black mark of the display layer and thus the slit By reducing the width w ′ of 10 images, more light passes through the pixel. In addition, the smaller pixel apertures and barrier slits typically reduce crosstalk. Furthermore, if the width w of the transmissive slit image 10 'is reduced, the divergence of light increases and the viewing angle range of the display is increased.

  While using the imaging means to generate an image of the parallax optic with a magnification of less than 1 provides the advantages described above, the significant disadvantage is that the pitch b ′ of the parallax barrier image 30 is also reduced, so A secondary window is created that overlaps the primary window, which results in crosstalk. In FIG. 7B, for example, the image 10 'of the transmissive slit 10 with a parallax barrier produces a primary observation window denoted A. The adjacent image 10'b of the transmissive slit 10 of the parallax barrier produces a secondary observation window denoted B. As can be seen in FIG. 7B, the two observation windows overlap and the observer located in the overlapping region is seen as crosstalk.

FIG. 7C is a schematic plan cross-sectional view of display device 32, according to a further embodiment of the present invention. The display of FIG. 7C generally corresponds to the display of 7B, in particular the imaging means (in this embodiment lenticular lens array 29) produces approximately half the magnification, so that the image of the elements of the parallax optic element. The width is approximately half the width of the elements of the parallax optical element. In FIG. 7C, the parallax optic is shown as a parallax barrier having a transmissive slit 10 and an opaque portion 11. The width w ′ of the transmissive slit image 10 ′ in the parallax barrier image 30 is approximately half the width w of the transmissive slit 10 of the parallax barrier 3. The components of the display of FIG. 7C that correspond to the display 28 ″ of FIG. 7B are no longer described.

  The display 32 of FIG. 7C further comprises blocking means for blocking the image of one or more elements of the parallax optic. In the display 32 of FIG. 7C, the blocking means blocks every other image of the transmissive slit 10 of the parallax barrier 3. Accordingly, the parallax barrier image 30 includes a transmissive region 10 ′ having a width w ′ substantially equal to half of the width w of the transmissive region 10 of the parallax barrier, and the pitch b ′ of the parallax barrier image 30 has a parallax barrier It is equal to or substantially equal to its own pitch b (w′≈1 / 2w, b≈b). Since the slit image 10 'has a smaller width than the parallax barrier slit 10, the benefits of improved brightness and improved viewing angle already described with respect to FIG. 7B also apply to the display 32 of FIG. 7C. However, since the pitch of the image 10 'of the transmissive slit 10 is equal to or substantially equal to the pitch of the transmissive slit 10 of the parallax barrier, the secondary observation window is erased and only the primary windows 13, 14 remain. Crosstalk present in the image displayed by the display 28 '' of FIG. 7B has been eliminated. Accordingly, the display 32 of FIG. 7C is particularly suitable for use as an autostereoscopic display, and the primary windows 13 and 14 correspond to left-eye and right-eye observation windows.

  In FIG. 7C, the blocking means may comprise a combination of a patterned polarizer 33 and a patterned half-wave retarder 34. The direction of the oblique line in the patterned polarizer 33 and the polarizers 8 and 9 indicates the direction of the transmission axis of the polarizer which is a linear polarizer in this embodiment. The elements of the patterned polarizer 33 are configured such that the transmission axis is alternately parallel to the transmission axis of the rear polarizer 8 of the image display element 2 and 90 °. That is, the patterned polarizer region 33A behind the transmissive slit 10A has a transmission axis parallel to the transmission axis of the rear polarizer 8, and the region 33B covering the slit 10B of the parallax barrier is the rear polarizer. For example, the transmission axis is 90 ° with respect to the eight transmission axes.

  The patterned half-wave retarder 34 includes regions 34A and 34C that alternately provide half-wave retardation with regions 34B having zero retardation. Each region 34A, 34B, 34C of the patterned retarder 34 typically corresponds to one lens of a lenticular lens array. The light passing through the central slit 10B of the parallax barrier 3 in FIG. 7C can pass through the central portion of the rear polarizer 8, which passes through a portion of the patterned polarizer having a + 45 ° transmission axis, Passes through the region where the retardation is zero, and then enters the polarizer 8 having a transmission axis of + 45 °. However, light passing through the upper or lower slits 10A, 10C of FIG. 7C is -45 ° polarized by the upper or lower elements 33A, 33C of the patterned polarizer and passes through the non-retarded region, +45 Blocked by a polarizer 8 having a transmission axis of °. Therefore, every other image of the slits in the parallax barrier is blocked.

  FIG. 7D shows a further display 32 'according to the present invention. This is generally similar to the display of FIG. 7C, and only the difference between the two displays is described.

  The display 32 'of FIG. 7D again comprises blocking means for blocking the image of selected elements of the parallax optic. The parallax optical element is again a parallax barrier, and due to the blocking means, the parallax barrier image 30 has a width that is approximately half the width of the slit of the parallax barrier, but has the same or almost the same pitch as the parallax barrier. It includes an image 10 ′ of the slit 10 of the parallax barrier. However, in the embodiment of FIG. 7D, the transparent slit image 10 'is arranged such that the primary window is not generated and the left and right secondary windows 35, 36 are generated. The left and right secondary windows are separated by a dark area 37 where the image is invisible. Accordingly, the display 32 'of FIG. 7D is particularly suitable for use in a dual view display intended to display two independent images to two different viewers. When the display 32 ′ is used as a dual view display, the first observer is placed in the left secondary window 36 to view one image and the second observation placed in the right secondary window 35. One sees a different image. The presence of a central dark area prevents the viewer from inadvertently viewing an inaccurate image when the viewer moves or changes head orientation.

  The blocking means in the display 32 ′ of FIG. 7D is again formed by a patterned linear polarizer 33 with different regions having orthogonal transmission axes and a patterned half-wave retarder 34. The patterned linear polarizer 33 is placed in the path of light through the transmissive slit 10 of the parallax barrier, and the patterned half-wave retarder is placed adjacent to the polarizer 8. The blocking means operates in a manner similar to the blocking means of FIG. 7C.

  FIG. 7E is a schematic plan sectional view of a further display 28 ″ ″ according to the present invention. This embodiment typically corresponds to the display 28 ′ ″ of FIG. 7B, in particular the imaging means (in this example the lenticular lands array 29) generates an image of the parallax optic, where the parallax optics The width of the element and the pitch of the parallax optical element are reduced by approximately ½. The display 28 ″ ″ of FIG. 7E is typically similar to the display 28 ″ of FIG. 7B, and only these differences will be described here.

  In the display 28 ″ ″ of FIG. 7E, the parallax optical element is a parallax barrier 3 having a transmissive slit 10 separated by an opaque portion 11. In this embodiment, the slit width and pitch of the parallax barrier are selected to provide the desired width of the slit image 10 ′ and the desired pitch b ′ in the parallax barrier image 30. In the case shown in FIG. 7E in which the lenticular lens array 29 generates an image having approximately half the magnification, the slit width w of the parallax barrier 3 is made approximately twice the desired slit width. This ensures that the width w 'of the slit image 10' in the parallax barrier image 30 has the desired width. Similarly, the pitch of the parallax barrier 3 is approximately twice as large as the desired size, so that the pitch b 'of the parallax barrier image 30 is equal to the desired pitch. As a result, prevention of the secondary observation window is suppressed and crosstalk is prevented. However, since the width w 'of the slit image 10' in the parallax barrier image 30 has a reduced width, the advantages of increased brightness and strong light divergence are retained.

  FIG. 7F shows a display 60 according to a further embodiment of the invention. The display 60 of FIG. 7F generally corresponds to the display 28 ″ of FIG. 7B and only the differences will be described. The display 60 of FIG. 7F comprises an opaque “flange” 57 extending between the parallax optic 3 and the imaging means 29 ″. This flange extends substantially parallel to the axis of the display and extends substantially across the entire vertical height of the display (ie, these flanges extend toward the plane of the paper in FIG. 7F). The distance d between adjacent 57 is equal to the pitch of the imaging means 29 '.

  The flange 57 is configured such that each element 29a, 29b, 29c of the imaging means can form a single image corresponding to the elements 10a, 10b, 10c of the parallax optical element 3. In FIG. 7F, the parallax optical element 3 is shown as a parallax barrier having transmissive apertures 10a, 10b, 10c, and the imaging means is shown as a lens array having lens elements 29a, 29b, 29c. The central lens element 29b shown in FIG. 7F can form an image of the central transmissive aperture 10b of the parallax barrier, for example, as shown in the figure. However, the center lens 29b of the lens array cannot form an image of the upper or lower apertures 10a, 10c of the parallax barrier. This is because the flange 57 prevents light passing through the upper or lower apertures 10a and 10c of the parallax optical element from reaching the center lens 29b of the lens array. Similarly, the upper lens element 29a of the lens array can form only an image of the upper slit 10a of the parallax barrier, and the lower lens 29c of the lens array can form only an image of the lower slit 10c of the parallax barrier.

  Therefore, in the parallax barrier image 30, the width of the image 10 ′ of each transmission slit 10a, 10b, 10c is reduced by the magnification of the lens array (in FIG. 7F, the lens array provides a magnification of about ½). However, this embodiment can be applied at any magnification less than 1). Thus, the advantages already mentioned in connection with the display of FIG. 7B are obtained. However, the presence of the opaque flange 57 means that the pitch of the parallax barrier image is equal to or substantially equal to the pitch b of the original parallax barrier 3. Therefore, generation of a secondary window is avoided and crosstalk is reduced. Since there is no secondary viewing window, the display is dark outside the primary viewing zone, which can be advantageous when the present invention is applied to a security screen. Thus, the flange 57 functions as a blocking means that blocks each element of the imaging means from forming an image of one or more elements of the parallax optic. These achieve the same results as the patterned polarizer 33 and the patterned half-wave retarder 34 of the embodiment of FIG. 7C.

  The substrate 12 'can be formed of several sections made of glass, and an opaque layer is placed between each section to form a flange. Alternatively, deep cuts are made in the substrate and each cut is filled with an opaque material to form the flange 57.

  FIG. 7G shows a display 62 according to a further embodiment of the present invention. The display 62 in FIG. 7G typically corresponds to the display 28 in FIG. 5 and the display 28 ″ in FIG. 7A, so only the differences will be described. In the embodiment of FIG. 7G, the imaging means 29 does not image the parallax barrier 3 in front of the imaging means 29, but instead generates a virtual image 30 of the parallax barrier 3 behind the imaging means 29. In this case, the separation s ′ between the parallax barrier image 30 and the display layer 4 is larger than the separation s between the actual parallax barrier 3 and the display layer 4. As a result, in the absence of the imaging means 29, the viewing angle separation is narrower than that generated for the actual parallax barrier 3 and the display layer 4.

  FIG. 7H shows a display 63 according to a further embodiment of the present invention. The display 63 of FIG. 7H typically corresponds to the display 62 of FIG. 7G, so only the differences will be described. In the embodiment of FIG. 7H, the imaging means 29 comprises a diverging lens that generates a virtual image 30 of the parallax barrier 3 behind the imaging means 29 and in this embodiment further in front of the parallax barrier 3, wherein The separation between the parallax barrier image 30 and the display layer 4 is smaller than the separation between the actual parallax barrier 3 and the display layer 4. As a result, in the absence of the imaging means 29, the observation angle separation is larger than that generated for the actual parallax barrier 3 and the display layer 4.

  FIG. 7I shows a display 64 according to a further embodiment of the present invention. The display 64 of FIG. 7I typically corresponds to the display 63 of FIG. 7H, so only the differences will be described. In the embodiment of FIG. 7I, the imaging means 29 is arranged in the vicinity of the image display layer 4 in front of the light transmissive substrate 5, not in front of the light transmissive substrate 12 ′. The imaging means 29 includes a diverging lens that generates a virtual image 30 of the parallax barrier 3 behind the imaging means 29 and in this embodiment, further in front of the parallax barrier 3 and inside the light transmissive substrate 5. The separation s ′ between the parallax barrier image 30 and the display layer 4 is smaller than the separation s between the actual parallax barrier 3 and the display layer 4. Thereby, in the absence of the imaging means 29, the observation angle separation is larger than that generated for the actual parallax barrier 3 and the display layer 4. A weak converging lens can also be used in the imaging means 29. The imaging means 29 can further be formed in one piece with the image display layer 4, for example, the imaging means can be formed from the microstructure of the pixel plane itself.

  FIG. 8A is a cross-sectional plan view of a display according to a further embodiment of the present invention. The display 38 of FIG. 8A generally corresponds to the display 28 of FIG. 5, so only the differences will be described.

  In the display 38 of FIG. 8A, the imaging means (in this embodiment forms an image of the parallax optic) has a variable focal length. The focal length of the imaging means is controlled by the controller 40. Therefore, it is possible to control the position of the image of the parallax barrier and thereby control the separation between the image display layer 4 and the image of the parallax barrier. This allows the viewing angle separation of the display to be controlled. For example, when the focal length is set so that the image of the parallax optical element is formed at a certain position 30a, the separation between the image and the image display layer 4 is relatively small, and thus a large observation angle is obtained. This is suitable for a display that operates as a dual view display when the image is intended to be viewed by different viewers. Conversely, when the parallax barrier image is formed at another position 30b, the separation between the parallax barrier image and the image display layer 4 is greater (however, between the parallax barrier and the image display layer). Separation is still small), which results in a smaller viewing angle than if the image of the parallax barrier is in the first position 30a, and this may be suitable for a display intended to be used as an autostereoscopic display . Here, the viewing angle must be selected so that the image separation corresponds to the separation between the human eyes. Therefore, it is possible to change the observation angle of the display 38 by appropriately controlling the focal length of the imaging means. This allows the viewing angle to be adjusted to suit a particular application, and in particular allows the display to switch between a dual view display mode and an autostereoscopic display mode. The display may be switched between a rear barrier mode in which the image of the parallax optical element is disposed behind the image display layer 4 and a front barrier mode in which the image of the parallax optical element is disposed in front of the image display layer 4. Is possible.

  Any suitable imaging means having a variable focal length can be used in the display 38 of FIG. 8A. For example, a mode liquid crystal lens, a pixelated liquid crystal lens, or a microlens structure filled with liquid crystal may be used. In each case, the focal lengths of these lenses vary depending on the voltage applied between the liquid crystal lenses. In this case, the controller 40 controls the voltage applied between the lens arrays. Therefore, the focal length of the imaging means can be easily controlled by using the controller 40 to control the magnitude of the voltage applied between the lenses.

  FIG. 8B is a schematic plan cross-sectional view of a further display 38 'according to the present invention. The display 38 'of FIG. 8B is generally similar to the display 38 of FIG. 8A, so only the differences will be described here.

  The display 38 'of FIG. 8B is further provided with tracking means 41 for determining the longitudinal distance between the display and the viewer. A controller 40 for controlling the focal length of the imaging means receives as an input an output signal from the tracking means 41 indicating the vertical distance between the display and the viewer. Accordingly, the controller 40 can change the focal length of the imaging means, and thus changes the position of the image 30 of the parallax optic based on the vertical distance between the viewer and the display. If the display is used in autostereoscopic mode, the viewing angle separation can be changed based on the vertical distance between the display 38 'and the viewer, which is the difference between the left and right viewing windows. It is possible to keep the separation between them equal to the separation between the eyes of the observer. In contrast, a conventional autostereoscopic display is intended to be viewed by an observer located at a fixed distance from the display, and viewing angle separation is performed for the left and right eye images at that distance. It is set so as to be accurately spaced with respect to the observer located in the position. However, as the viewer moves toward or away from the display, the lateral separation between the viewing windows increases or decreases and is therefore not equal to the separation between the viewer's eyes.

  FIG. 8C is a schematic plan cross-sectional view of a display device 38 ″ according to a further embodiment of the present invention. In this embodiment, the imaging means is also a variable focal length imaging means, the focal length of which is controlled by a suitable controller 40.

  In the display 38 ″ in FIG. 8C, the parallax optical element is the parallax barrier 3. The variable focal length imaging means 39 is configured to generate an image of the parallax barrier in the plane of the image display layer 4. Furthermore, as schematically shown in FIG. 8C, the width and pitch of the parallax barrier, and the magnification generated by the imaging means 39 are such that the image of the parallax barrier 30 is in the plane of the image display layer 4 or the image display layer 4 It is configured so as not to have a black area imaged behind the plane. (In FIG. 8C, the parallax barrier has a ratio of black area to transmissive slit of 2: 1, and the image of the parallax barrier at the position 30C is magnified about 3 times.) Therefore, the parallax barrier 3 is effective. The two-dimensional display mode can be acquired. Thus, the display device can be switched between a 3D display mode and a 2D display mode by controlling the imaging means to provide an appropriate image of the parallax barrier 3. If the image of the parallax barrier provides a black area imaged behind the pixel plane, as shown at 30B in FIG. 8C, the 3D display mode will result as shown in FIG. 5 or FIG. .

  The display device 38 '' of FIG. 8C can be further switched between different three-dimensional display modes. For example, the focal length of the lens array 39 may be determined in a dual view display mode or an autostereoscopic display mode, as well as in a 2D display mode (as described previously with reference to FIG. 8B). Need to be more complex optics such as those shown).

  FIG. 9A is a cross-sectional plan view of display device 42 in accordance with a further embodiment of the present invention. This embodiment generally corresponds to the display device 28 of FIG. 5, so only the differences will be described.

  The display device 42 of FIG. 9A includes imaging means formed of multiple lens layers. In FIG. 9A, three layers 43, 44 and 45 are shown, each layer constituting a lenticular lens array. Two of these layers comprise lenses with variable focal lengths. These lenses are the central lens 44 and one other lens layer (in FIG. 9A, the central lens layer 44 and the right lens layer 45 are controllable). As already described with respect to the display of FIG. 8A, the lens having a variable focal length may be a liquid crystal lens. The focal lengths of the variable focal length lens layers 44, 45 are controlled independently of each other by a suitable controller (not shown). This embodiment allows independent control of the focal length and magnification of the imaging means. Thus, as already described with reference to FIGS. 8A-8C, the display 42 can be switched between a two-dimensional display mode and a three-dimensional display mode and / or between different three-dimensional display modes. .

  The embodiment of FIG. 9A provides independent control of both the focal length and magnification of the imaging means, so that the image pitch of the parallax optic (or image display layer) is always parallax, regardless of the position of the image. It is possible to ensure that it is equal to the pitch of the optical element (or image display layer). In contrast, in 8A, 8B and 8C embodiments where only the focal length of the imaging means can be controlled, it is possible to actually change the magnification of the imaging means by changing the focal length of the imaging means. In this case, the image pitch of the parallax optical element (or the image display layer) slightly changes depending on the position of the image. This can cause the formation of secondary windows at several positions in the image of the parallax optic (or image display layer), which can be, for example, the techniques of FIG. 7C, FIG. 7D or FIG. 7F. Can be erased using.

  FIG. 9B shows a display 43 according to a further embodiment of the invention. The display 46 in this embodiment is intended to allow tracking of an observer moving laterally relative to the display.

  The imaging means of the display 46 comprises two disabling lens arrays 47, 48, one behind the other. The two lens arrays 47, 48 have the same pitch but are offset laterally relative to each other by about 1/8 of the pitch in FIG. 9B. The focal lengths of the two lens arrays are approximately the same so that the arrays 47, 48 are in the same longitudinal position but are offset laterally relative to each other by a quarter of the pitch. 3 images 30A and 30B are generated. (In FIG. 9B, the two images of the parallax optical elements 30A, 30B are shown as being offset in the vertical direction, but this is only for clarity of illustration and the two images 30A, 30B are Preferably on the same plane).

  The two lens arrays 47 and 48 can be controlled independently by means of the controller 40. In particular, the controller 40 may enable one of the lens arrays 47, 48 and disable the other array.

  The display 46 further includes tracking means 41 for tracking the position of the observer in the lateral direction with respect to the display. The controller 40 receives as an input an output signal from the tracking means 41 that provides information about the observer's lateral position. Depending on the viewer's lateral position relative to the display, the controller 40 may select either of the lens arrays 47,48. Since the parallax optic images 30A, 30B generated by the two lens arrays are laterally offset by 1/4 of the pitch, the observation window generated by the lens array 47 is the observation generated by the lens array 48. It is shifted angularly from the window. In FIG. 9B, the position of the center of the primary observation window generated by the lens array 47 is indicated by a solid line, and the position of the center of the observation window generated by the lens array 48 is indicated by a broken line.

  Therefore, by switching from one lens array to another, it is possible to shift the observation window in the horizontal direction and follow the movement of the observer.

  One method for providing switchable lens arrays 47, 48 will now be described. In this method, each lens array is composed of liquid crystal lenses 47a and 48a disposed on transmissive substrates 47b and 48b such as glass. If the refractive index of the lenses 47a, 48b matches the refractive index of the surrounding substrates 47b, 48b, the lens is effectively disabled and does not produce a lensing effect, but the lenses 47a, 48a When the refractive index of the liquid crystal material is different from the refractive index of the respective substrates 47b and 48b, a lens effect is generated. Therefore, an appropriate voltage is applied across the liquid crystal material of lenses 47a, 48a, thereby controlling one of the lens arrays by controlling their refractive index while defeating the other lens array. Is possible.

  In an alternative embodiment (not shown), the lens arrays 47, 48 cannot be controlled. In this embodiment, one lens array has a refractive index matching with the surrounding substrate for a certain polarized light, and the other lens array 48 has a lens array for light in an orthogonal polarization state. The refractive index matches that of the surrounding substrate. In this case, either of the lens arrays can be selected by controlling an appropriate polarization switch (not shown) that controls the polarization of light incident on the lens array.

  FIG. 9C shows a further display 49 according to the invention. Furthermore, the display 49 can change the angular position of the observation window, for example, to follow the lateral movement of the observer.

  In the display of FIG. 9C, the imaging means, here shown as a conventional lenticular lens array 29, is configured to be movable laterally with respect to the parallax optical element. In FIG. 9C, the imaging means is shown to be mechanically movable, but in addition to or instead of the imaging means, the parallax barrier can be movable laterally. By changing the lateral position of the imaging means relative to the parallax optical element, the lateral position of the image of the elements of the parallax optical element is also changed. When the parallax optical element is a parallax barrier, for example, the horizontal position of the image 10 ′ of the transmissive slit 10 of the parallax barrier is changed by changing the horizontal position of the imaging unit with respect to the parallax barrier. This changes the angular position of the viewing window generated by the display 49, as described with respect to FIG. 9B.

  The controller 40 receives as an input an output signal from a tracker 41 that tracks the lateral position of the viewer with respect to the display 49. The lateral position of the imaging means with respect to the parallax barrier is controlled by the controller 40 based on the input from the tracker 41, thereby changing the angular position of the observation window to follow the lateral movement of the observer. .

  The remaining components of display 49 correspond to the components of display 28 of FIG. 5 and are therefore not further described.

  In the modification of this embodiment, the parallax barrier 3 is embodied as a spatial light modulator such as a liquid crystal panel, for example. In this embodiment, the lateral movement of the parallax barrier is simulated by re-addressing the spatial light modulator, and the lateral position of the transmissive slit of the parallax barrier moves in the lateral direction.

  FIG. 9D is a cross-sectional plan view of a further plurality of view directional displays 49 'of the present invention. Display 49 'generally corresponds to display 49 of FIG. 9C, and thus features of display 49' common to display 49 of FIG. 9C are described again.

  In the display of FIG. 9D, the position of the imaging means shown here as a conventional lenticular lens array 29 is fixed relative to the parallax optical element 3 shown here as a parallax barrier. This can be done by mounting the imaging means on one of the substrates 12 'of the parallax optic. The imaging means and the parallax optic can move together relative to the image display device 2. In FIG. 9D, the imaging means and parallax optic are shown to be mechanically movable, but it is possible for the image display device to be movable in addition to or instead of the imaging means.

  The imaging means 29 and the parallax optical element 3 may be movable together in the horizontal direction and / or the vertical direction with respect to the image display device 2. By changing the horizontal position of the imaging means and the parallax optical element with respect to the image display device, the horizontal position of the image of the element of the parallax optical element also changes. As described with respect to FIG. 9B, this changes the angular position of the viewing window generated by the display 49 ′, thereby allowing tracking of observers moving laterally relative to the display. .

  By changing the vertical position of the imaging means and the parallax optical element with respect to the image display device, the vertical position of the image of the element of the parallax optical element also changes. As described with respect to FIG. 8B, this modifies the viewing angle separation of the viewing window generated by the display 49 ′, thus allowing the display to track a viewer moving vertically relative to the display. To do. The display may provide a constant lateral separation between the viewing windows regardless of the vertical distance between the display and the viewer.

  The horizontal and / or vertical movement of the imaging means and parallax optic with respect to the image display device is controlled by the controller 40. Where the imaging means and the parallax optic can move both laterally and longitudinally relative to the display, the controller 40 preferably controls lateral and longitudinal movements independently of each other.

  The controller 40 may receive as input an output signal from an observer tracking device 41 that tracks the observer's vertical and / or horizontal position relative to the display 49 '. Based on the output from the observer tracking device 41, the controller 40 can control the vertical and / or horizontal positions of the imaging means and the parallax optical element with respect to the image display device.

  FIG. 10 is a cross-sectional plan view of a further display 28 ″ ″ ″ of the present invention. In this embodiment, the present invention is applied to a front barrier display, where the parallax optic is placed in front of a pixelated display layer rather than an image of the parallax optic.

  In FIG. 10, the parallax optical element is shown as a parallax barrier 3 having a light transmissive slit 10 separated by an opaque region 11. The imaging means is shown as a lenticular lens array having a pitch that is substantially equal to or an integer multiple of the pixel pitch of the pixelated display layer 4. The lenticular lens array 29 forms an image of the image display layer 4, whereby the vertical separation s ′ between the parallax barrier 3 and the image 30 of the image display layer 4 is separated from the parallax barrier 3 and the image display layer. 4 is smaller than the vertical separation between the two. Thus, the observation angle separation is magnified, as already explained with reference to FIG.

  The remaining components of the display 28 "" "of FIG. 10 generally correspond to the components of the display 28 of FIG. 5, and therefore the description regarding these components will not be repeated here. However, it should be noted that the image display layer 4 of this embodiment can be a transmissive image display layer that is illuminated by a backlight (not shown) or a light emitting display layer such as a plasma or organic light emitting device (OLED) display layer. I want to be.

  In the display of FIG. 10, the image 30 of the image display layer is formed in the display, and the lenticular lens array has a fixed focal length and produces a magnification of approximately unity. Basically, however, the embodiments of FIGS. 6-9C can all be applied to a front barrier display of the type shown in FIG. 10 (however, in practice, the displays of FIGS. Can be difficult to implement as the primary image can overlap with the secondary image of the opposing pixel).

  In the display of FIG. 10, the image 30 of the image display layer is formed in a state where the pitch is substantially the same as the pitch of the image display layer 4. It is also possible to configure the lens array 29 to have a different pitch that is larger or smaller with respect to the image display layer 4. When the pitch of the lens array 29 is configured to have a larger pitch, the resulting pitch of the image display layer image 30 is greater than the pitch of the image display layer 4, resulting in viewing angle separation. Expand further.

  FIG. 11 shows a display 50 according to a further embodiment of the invention. Features of the display 50 that are common with the display 28 of FIG. 5 are no longer described.

  In this embodiment, the imaging means includes a lens array 51. A flat surface perpendicular to the axis of the display is formed on the lens 52 of the lens array. Instead, the lens 52 is mounted on the microstructure 53 so that the flat surface of the lens 52 makes an angle with the longitudinal axis relative to the display.

  The focal lengths of the lenses 52 are the images of the elements of the parallax optic where these lenses coincide with the pixels 54 of the pixelated display layer 4 (in this case the image 10 'of the transmissive slit 10 of the parallax barrier 3). Configured to generate. That is, the transmissive slit image 10 ′ is in the plane of the pixelated display layer 4 and coincides with or substantially coincides with the display area of the pixels 54 of the image display layer 4.

  The image 10 ′ of the slit 10 forms an angle with the plane of the image display layer 4 as schematically shown in FIG. 11. This is a result of the lens 52 being mounted on the microstructure 53. As a result, the display 50 can provide a good viewing window at a relatively large angle from the normal axis to the display. Aberrations that occur over a wide viewing angle in conventional displays are eliminated or significantly reduced in the display 50 of FIG. The slit image 10 'is focused on the plane of the image display layer. This is because there are two lenses for each barrier slit. When the slit image 10 ′ is in front of or behind the image display layer, in general, a double slit image is generated and the 3D observation window is not swamped.

  The embodiment of FIG. 11 may further be embodied with a front barrier display in which the parallax optical element is disposed in front of the image display layer 4.

  In the embodiment described above, the viewing angle of the cone drawn by the vignetting of the lens light determines the maximum viewing angle that can be seen. These lines are marked in the figure for this embodiment. Note that for a magnified image where the image size is larger than the original slit width, the cone angle is also reduced. This is part of the basic principle behind the embodiment already described with reference to FIG. 7D.

  FIG. 12 is a cross-sectional plan view of a display 55 according to a further embodiment of the present invention. Features of the display 55 that are common with the display 28 of FIG. 5 are no longer described.

  In this embodiment, the diffuser layer 56 is disposed on one of the substrates of the image display device 2. In FIG. 12, it is shown that the diffuser layer 56 is disposed in the first substrate 5, which is thus formed of two substrates 5a, 5b sandwiching the diffuser layer. 56 may alternatively be provided on the second substrate 6 of the image display element.

  The diffuser layer is disposed substantially perpendicular to the axis of the display. The display 55 in FIG. 12 is a rear barrier display in which the imaging means (the lenticular lens array 29 in FIG. 12) forms the image 30 of the parallax optical element. In this embodiment, the diffuser layer is arranged such that the image 30 of the parallax optical element substantially coincides with the diffuser layer. The parallax optic image 30 and the diffuser layer 56 are shown in FIG. 12 to be separated in the vertical direction, for clarity of explanation, and the diffuser layer has the parallax optic image 30. It is preferable that they are arranged so as to coincide with the plane of the diffuser layer.

  The cone angle of the display depends on the divergence angle of the light focused on the focal plane, after which there is vignetting. By providing the diffuser layer 56, the viewing angle of the display is improved.

  In the diffuser layer 56 of FIG. 12, the imaging means generates an image of the parallax optical element and has a fixed imaging power, whereby the position of the image of the parallax optical element is fixed. It can be applied to any previously described embodiment in which an image of the element is formed in the display. The embodiment of FIG. 12 assumes that the imaging power of the imaging means generates the image of the image display layer 4, assuming that the imaging power of the imaging means is fixed, thereby also fixing the position of the image of the image display layer. This embodiment can also be applied.

  The diffuser layer of FIG. 12 can also be applied to displays that are switchable between 3D and 2D modes. For example, the diffuser layer 56 may be incorporated into a display of the type shown in FIG. 8C that is operable in 3D or dual view display mode and 2D display mode. The diffuser layer is positioned to match the image of the parallax optic in 3D or dual view display mode, and the enlarged viewing angle is acquired in 3D or dual view display mode. In 2D mode, the image of the parallax barrier is formed sufficiently away from the diffuser layer, so that the diffuser layer is a uniform backlight in 2D display mode.

  FIG. 13A is a schematic plan cross-sectional view of a further multi-view directional display 58 according to the present invention. Display 58 generally corresponds to display 55 of FIG. 12, and features common to both displays are no longer described.

  In the display 58 of FIG. 13A, the imaging means 29 has a variable focal length, for example, a lens array having a variable focal length shown in FIG. 13A. The parallax optical element 3 and the imaging means 29 are configured to provide an image of the parallax optical element with a small image of the elements of the parallax optical element. When the parallax optical element is a parallax barrier, for example, a parallax barrier having a relatively narrow slit may be used. Additionally or alternatively, imaging means having a magnification smaller than 1 can be used, so that the image of the slit 10 'in the parallax barrier image 30 as already described with reference to FIGS. 7B-7E. However, the width becomes narrower than the slit 10 in the parallax barrier.

  The focal length of the imaging means can be controlled using a suitable controller (not shown) to change the position of the image 30 of the parallax optic. Accordingly, the image 30 of the parallax optical element can be formed behind the diffuser or on the plane of the diffuser. Therefore, by controlling the position of the image 30 of the parallax optical element, the size of the image of the element of the parallax optical element in the diffuser can be changed, thereby changing the effective size of the image of the element of the parallax optical element. Is possible, and therefore the effective size of the elements of the parallax optic can be controlled. The viewing angle separation is constant regardless of the effective size of the elements of the parallax optical element and is determined by the separation between the diffuser layer and the image display layer.

  The display 58 of FIG. 13A controls the focal length of the imaging means so that the parallax optic image is formed away from the diffuser layer 56 so that the diffuser layer functions as a uniform backlight. It may also be operable in 2D display mode.

  If the imaging means 29 can be disabled, the display 58 of FIG. 13A may be operable in a 2D display mode. By disabling the imaging means, an image of the parallax barrier is not formed. As shown in FIG. 13B, the light from the parallax barrier 3 is diffused by the diffuser layer 56, and the 2D display mode is acquired again. The disableable imaging means of this embodiment may be constituted, for example, by the disableable lens arrays 47, 48 of the embodiment of FIG. 9B.

  The embodiment of FIGS. 12 and 13 can also be applied to a front barrier display in which a parallax optical element is disposed in front of the image display layer 4.

  In the embodiment of FIGS. 8A to 13, the pitch of the parallax optical element images (or the image display layer image) is equal to or substantially equal to the pitch of the parallax optical elements (or image display layer).

  The embodiments of FIGS. 8B, 9B, 9C, and 9D that incorporate an observer tracker may further be provided with means for identifying the user of the display. For example, the display may have a tracking / identification device 26 that may track the position of the user's eyes and also identify the user. For example, the tracking device 41 of FIG. 8B, FIG. 9B, FIG. 9C or FIG. 9D may comprise an iris sensor and / or a fingerprint sensor that includes information about the authorized user's iris or fingerprint pattern on the display. When a person attempts to activate the device, the tracking device 41 determines whether the person is an authorized user of the system and allows the system to be activated only by authorized users. The tracking device 41 may further store information regarding the display mode most frequently used by each authorized user, and at system startup, the tracking device 41 drives the display in the display mode preferred by the user. It is desirable to instruct the controller 40.

  In the above-described display, the substrate, polarizer, parallax barrier, and lens array can be made from any suitable material. The image display layer 4 can basically be any pixelated display layer. In embodiments where the image display layer is disposed in front of the parallax optical element, any transmissive image display layer may be used, and in embodiments where the image display layer is disposed behind the parallax optical element, any transmission Or a luminescent image display layer may be used.

  Depending on the nature of the image display layer 4, the polarizers 8, 9 of the image display device 2 may be unnecessary.

  The invention can also be used to obtain an asymmetric viewing window, i.e. to provide a display in which the angular spread of one observation window is not equal to the angular spread of the other observation window. This can be done by using an imaging system that generates an image of the parallax optic offset laterally with respect to the image display layer, or an image of the image display layer offset laterally with respect to the parallax optic. Can be done. This can be achieved by proper lateral alignment of the imaging means.

  The generation of an asymmetric viewing window is described in partially pending UK patent application No. 0320365. One technique for obtaining the asymmetric viewing window disclosed in this partially pending application is to use a parallax barrier that is substantially misaligned with respect to the image display layer. It is known that the pitch of the parallax barrier is slightly smaller than the pitch of the pixelated image display panel, providing “viewpoint correction”. In such displays, the parallax barrier aperture and the image display panel There is a slight amount of misalignment between the pixel (or pixel column). However, in the above-mentioned co-pending application, the misalignment between the parallax barrier and the image display layer is significantly greater than in known displays. For example, in the center of the display, the aperture of the parallax barrier is offset by approximately 20 ° from the accurately aligned position. This misalignment effect makes one observation window smaller and thus produces an observation window with a different angular spread on the other.

  An image of the parallax optical element substantially displaced with respect to the image display layer is generated (or the parallax optical element in the parallax optical element) by appropriately adjusting the lateral position of the imaging unit in the above-described embodiment of the present invention. An image of the image display layer that is substantially misaligned to the other), thereby creating an asymmetric viewing window as taught in co-pending UK patent application No. 0320365.0. is there.

  The embodiment of FIG. 9C can provide a display that can be controlled to provide a symmetric or asymmetrical viewing window. When the lens array is accurately aligned with the parallax optical element, the image of the parallax optical element is aligned with the image display layer and a symmetric observation window is obtained. By moving the lens array laterally with respect to the parallax optical element, it is possible to generate an image of the parallax optical element that is largely displaced with respect to the image display layer, thereby generating an asymmetric observation window. is there. This is also true for the deformation of the front barrier of FIG. 9C.

  FIG. 14 shows a multi-view directional display 59 of the present invention that can generate an asymmetric viewing window. The display 59 generally corresponds to the display 28 of FIG. 5, so only the differences between the display of FIG. 14 and the display of FIG. 5 will be described here.

  In the display 59 of FIG. 14, the imaging means is asymmetric, where the imaging power is not constant for each element of the imaging means. In the specific imaging means shown in FIG. 14, the imaging means is a lens array 29 having asymmetric lenses. Each lens includes a portion 29a having a long focal length and a portion 29b having a short focal length. Accordingly, the lens array 29 generates two images of the parallax barrier. The first image 30a of the parallax barrier is generated by the lens portion 29a of the lens array having a long focal length. The second image 30b of the parallax barrier is formed by the lens portion 29b of the lens array having a short focal length, and thus the second image 30b of the parallax barrier is the first image 30a of the parallax barrier and the lens array 29. Located between and. The two images 30a, 30b of the parallax barrier are aligned laterally with respect to each other. Furthermore, the two images are substantially the same size.

The two images are displayed in an interlaced manner on the image display layer, and FIG. 14 is displayed on the left eye image displayed on the pixel columns C1, C3, and C5 and on the pixel columns C2, C4, and C6. The right-eye image is shown. The pixel column that displays the image for the left eye is illuminated with light that has passed through the short focal length region 29b of the lens, whereas the pixel column that displays the image for the right eye displays the long focal length region 29a of the lens. Irradiated with light passing through. Therefore, the separation between the image display layer 4 and the parallax barrier image differs between the left-eye image and the right-eye image. The separation of the left-eye image (S _L ) is equivalent to the separation between the short focal distance image 30b of the parallax barrier and the image display layer 4, but the separation of the right-eye image (S _R ) Separation between the long focal length image 30a and the image display layer 4, and therefore S _L > S _R. Therefore, the observation window 14 for the right eye image has a larger angular spread than the observation window 13 for the left eye image.

  The embodiment of FIG. 14 can also be applied to a display in which the imaging means forms an image of the image display layer.

  FIG. 15 is a cross-sectional plan view of a multi-view directional display 63 according to a further embodiment of the present invention. The display 63 comprises an image display device that includes a pixelated image display layer 4 disposed on a light transmissive substrate 5. The display 63 is illuminated by light 7 from a light source (not shown) arranged behind the display. The image display layer can be any transmissive display layer, and in this embodiment the image display layer 4 is a liquid crystal layer such as, for example, an active matrix TFT liquid crystal display layer. The image display device includes first and second polarizers arranged one by one on each side of the image display layer 4 and first and second substrates arranged on the opposite side of the image display layer 4 shown in FIG. 2 further includes components such as addressing means such as pixel electrodes for addressing the pixels of the liquid crystal layer, switching elements, etc., but these may be entirely conventional and are therefore omitted in FIG. Has been.

  The display 63 further includes a parallax optical element 3 disposed behind the image display element. In this embodiment, the parallax optical element 3 is a parallax barrier having light-transmitting slits 10 separated by an opaque portion 11 and extending toward the paper surface in FIG. In operation, the driving means (not shown) drives the pixelated display layer 4 to display two interlaced images, which are shown in FIG. C3, C5 are labeled “R” to indicate one image, and the other pixel columns C2, C4, C6 are labeled “L” to indicate the other image (the pixel column is shown in FIG. 15). Extending towards the paper surface). This is intended to show that one image is displayed on the pixel columns C1, C3, C5 and is visible in the right viewing window. The second image is displayed on the other pixel columns C2, C4, C6 and is visible in the right viewing window.

  The display 63 further includes two imaging means 60 and 61 provided between the parallax barrier 3 and the image display layer 4. In the embodiment of FIG. 15, each imaging means 60, 61 is composed of a lenticular lens array. Each lens of each lenticular lens array has a pixel column C1. . . It extends substantially parallel to C6. Although it is shown in FIG. 15 that the two lenticular lens arrays are formed on opposite surfaces of a common light transmissive substrate 62, basically each lens array can be formed on a separate substrate.

  FIG. 15 shows a lenticular lens array as the imaging means, but the invention is not limited to this particular type of imaging means. Basically, any convergent diffraction or refractive microstructure (eg, Fresnel lens) can be used in place of a regular lens. The imaging means can further be formed using holographic optical elements.

The principle of operation of the display 63 is that the parallax barrier 3 and the first imaging means 60 generate a directional illumination region. In the embodiment of FIG. 15 where the first imaging means 60 is a lenticular lens array, the portion of light that passes through the aperture 10 of the parallax barrier 3 is incident on the portion 60R of the lenticular lens and generally toward the right viewing window. And the portion of light is incident on the adjacent lenticular lens portion 60L and is generally directed toward the left viewing window. (The terms “right” and “left” refer to the orientation of the display as seen by an observer viewing the display from a normal viewing position.)
The second imaging unit 61 images the directional illumination pattern generated by the parallax barrier 3 and the first imaging unit 60 on the image display layer 4 (or on a plane close to the plane of the image display layer). . As a result, the pixel columns C2, C4, C6, etc. that display the left image are mainly irradiated by light traveling toward the left observation window, and the pixel columns C1, C3, C5, etc. that display the right image It is mainly irradiated by light traveling toward the observation window. The two images are displayed in different directions, thereby creating a multi-view display.

  The display 63 of FIG. 15 provides greater image brightness (compared to a standard parallax barrier display). In a conventional display of the type shown in FIG. 1, regardless of whether the pixel is displaying a left image or a right image, the pixel in the image display layer is caused by light directed to the left. Illuminated and illuminated by light directed to the right. However, in the display 63 of FIG. 15, the lens array redistributes the light passing through the transmissive region 10 of the parallax barrier 3 so that the pixels of the image display layer displaying the left (or right) image are Illuminated primarily by light directed to the left (or right). This allows the transmissive area 10 of the parallax barrier to be wider than in a conventional parallax barrier display. A further advantage of the display 63 of FIG. 15 is that crosstalk is reduced.

  Since the pixel column displaying the left (or right) image is mainly illuminated by light directed to the left (or right), the display 63 further provides a smaller image mixing zone. Furthermore, the first imaging means directs little light along the axis of the display or no light at all, which is an intensity between the left image and the right image. Provides a weak area.

  The focal lengths of the imaging units 60 and 61 are such that the first imaging unit 60 images the barrier 3 on the plane of the second imaging unit 61, and the second imaging unit 61 uses the first imaging unit 60. It is preferable to image the plane of the image display layer 4. Therefore, the separation between the parallax barrier image and the image display layer is smaller than the separation between the parallax barrier and the image display layer, so that the angular separation between the left view and the right view is Zoom in as described for the previous embodiment. This makes it possible to achieve a large angular separation between views, while the imaging means and the parallax barrier 3 are relatively far from the image display layer. This may make the production of the system easier, for example by allowing both the substrate 5 and the substrate 62 of the imaging means to be made relatively thick and robust. The substrates 5, 62 can have a thickness of about 0.5 mm, for example.

  The pitch of the lenses is such that the pitch of the first imaging means 60 is substantially the same as the pixel pitch of the image display layer 4, and the pitch of the second imaging means 61 is substantially the same as the pixel pitch of the image display layer 4. Preferably they are the same or nearly double.

  The element of the second imaging means is preferably aligned with the element of the first imaging means. For example, when the imaging means is composed of a lenticular lens array, it is preferable that the lenticular lens 61a of the second lenticular lens array is directly aligned with the corresponding lenticular lens 60a of the first lenticular lens array. However, other configurations are possible. The pitch of the parallax optical elements 3 is preferably twice the pitch of the first imaging means. Each element of the parallax optical element is preferably substantially aligned with the boundary between the two elements of the first imaging means 60, so the parallax optical element is a parallax barrier and the first imaging means is a lens array. , The center of each transmissive region 10 of the parallax barrier 3 is approximately aligned with the boundary between the two lens elements of the first lens array 60, as shown in FIG.

  Aligning the parallax optic shown in FIG. 15, the first lens array, and the second lens array provides left and right viewing windows that are symmetrically configured about the normal axis of the display. To do. A lateral misalignment between either the parallax optic, the first lens array or the second lens array does not affect the position of the two observation windows, but crosstalk between the two observation windows Bring.

  A spacer (not shown) may be provided to ensure that the separation between the first imaging means 60 and the parallax barrier 3 is maintained at a desired value. For example, the first imaging means 60 may have spacer columns (at irregular spatial intervals) to maintain the separation between the first imaging means 60 and the parallax barrier 3.

  The parallax barrier 3 may be a fixed parallax barrier in which the opaque region 11 is disposed on a light transmissive substrate (not shown). Alternatively, the parallax barrier 3 can be a parallax barrier that can be disabled, for example, the transparent region 10 and the opaque region 11 can be defined in an addressable layer, such as a liquid crystal layer, for example, The barrier can be disabled by switching the liquid crystal so that it has uniform transparency across the area. By using a parallax barrier that can be disabled, the display 63 can be switched to a conventional 2D display mode.

  FIG. 16 is a cross-sectional plan view of a further display 63 'of the present invention. The display 63 'corresponds in various ways to the display 63 of FIG. 15, so only the differences between the two displays are described.

  In the display 63 'of FIG. 16, the parallax barrier 3 of FIG. 15 and a separate backlight are not present. Instead, the display 63 'is provided with a backlight 66 comprised of a waveguide 64 and one or more light sources 65 disposed along the side of the waveguide. Although two light sources 65 arranged along the side surfaces 64a and 64b on both sides of the waveguide 64 are shown in FIG. 16, the present invention is not limited to the specific configuration of the backlight shown in FIG. One light source or more than two light sources may be used. The light source 65 preferably extends along all or substantially all of the respective side surfaces of the waveguide, and may be, for example, a fluorescent lamp.

  As is well known, light from the light source 65 enters the waveguide 64, is captured in the waveguide 64 by the phenomenon of total internal reflection, and is incident on the front surface 67 or the rear surface 68 of the waveguide 64. The light propagating in the wave tube does not emit from the waveguide through total internal reflection.

  According to the embodiment of FIG. 16, diffusing dots are provided in selected areas 69 on the rear face 68 of the waveguide. The light propagating into the waveguide is incident on a region 69 on the back surface 68 of the waveguide, where if diffuse dots are provided, the light will not be specularly reflected from the back surface 68, rather, as shown in FIG. As scattered by the diffusing dots. Accordingly, some of the scattered light is incident on the front surface 67 of the waveguide at an angle smaller than the critical angle with respect to the normal, and is therefore reflected out of the waveguide toward the image display layer 4.

  Light is scattered from the waveguide 64 only in the region 69 where the diffusion dots exist, and does not emit from the waveguide 64 without the diffusion dots. Therefore, the waveguide 64 has a region that emits light (corresponding to the region 69 where the diffusion dots exist) and a region that does not emit light strongly. When the region 69 where the diffusing dots are present has a strip shape extending toward the paper surface of FIG. 16, the region of the waveguide 64 that emits light is the transmissive region of the parallax barrier 3 of FIG. 10, the region of the waveguide 64 that does not emit light corresponds to the opaque region 11 of the parallax barrier 3 in FIG. 15 in size, shape, and position. Therefore, the backlight 66 of the display of FIG. 16 combines the conventional backlight of the display of FIG. 15 and the parallax optical element 3, and the second lens array can be considered as imaging the parallax optical element. The separation between the image of the parallax optic and the image display layer is smaller than the separation between the parallax optic and the image display layer, so that the angular separation between the left view and the right view is Enlarging as described in the embodiments, the advantages of the above-described embodiments are retained.

  The regions 69 of the waveguide 64 that are free of diffusing dots can be coated with an absorbent material to ensure that no light is scattered from these regions. This reduces the intensity of light emanating from the region of the waveguide that is intended to correspond to the opaque region 11 of the parallax barrier 3 of FIG.

  The diffusing dots may be provided on the front surface 67 of the waveguide and / or the rear surface 68 of the waveguide.

  The diffusing dots can consist of a diffusing structure, a diffractive structure, or a fine refractive structure. Assuming that light scatters from areas 69 where diffusing dots are provided and does not scatter strongly in areas where diffusing dots are not provided, it is immaterial whether the structure of these dots is precise.

  The front surface 67 of the waveguide 64 and the surface of the first imaging means can be formed such that precise alignment between the waveguide 64 and the first imaging means is automatically provided.

  FIG. 17 is a cross-sectional plan view of a further display 63 ″ of the present invention. Display 63 '' generally corresponds to display 63 of FIG. 15, so only the differences will be described.

  The display 63 ″ of FIG. 17 again has a backlight 66 composed of a waveguide 64 and at least two light sources 65a and 65b arranged along the side surfaces 64a and 64b of the waveguide 64. Provided. Although two light sources 65a, 65b disposed along both sides of the waveguide 64 are shown in FIG. 16, the present invention is not limited to a particular configuration of backlight. The light sources 65a, 65b preferably extend along all or substantially all of the respective side edges of the waveguide, and may be, for example, fluorescent lamps.

  The backlight 66 includes at least one light source 65b that emits light in the visible spectrum. The backlight further includes at least one light source 65a that does not emit light in the visible spectrum and emits only at wavelengths outside the visible spectrum, for example, only at wavelengths in the ultraviolet region of the spectrum. The visible light source 65b and the light source 65a outside the visible spectrum can be controlled independently of each other.

  In the backlight 66, the back surface 68 of the waveguide 64 is made rough rather than flat so that light propagating through the waveguide 64 and incident on the back surface 68 of the waveguide is scattered rather than specularly reflected. Is done. As a result, when the light source 65b emits visible light (and the other light sources 65a are off), the waveguide 64 emits visible light from this front surface with a substantially uniform intensity over the entire area. Therefore, the display 63 ″ functions as a conventional 2D display and does not produce a directivity effect.

  A material 70 that emits visible light when illuminated by light from a light source 65 a of light outside the visible spectrum is provided in selected areas of the rear surface 68 of the waveguide 70. In an embodiment in which the light source 65a emits ultraviolet light, the material 70 can be, for example, a material that emits fluorescence and emits visible light when irradiated with ultraviolet light. The spectrum of light emitted by the visible light source 65b and the material 70 is preferably selected such that the material 70 is completely inert when illuminated only by the visible light source 65b.

  When the light source 65a is on and the visible light source 65b is off, ultraviolet light enters the waveguide and is incident on the material 70 region. Visible light is emitted from the material 70 but is not emitted in the region 71 where the material 70 is not present. As a result, visible light is emitted only from the waveguide 64 in which the material 70 is present, and is not emitted from the waveguide 64 in which the material 70 is not present. Accordingly, the waveguide 64 has a region 71 that emits visible light (corresponding to a region where the material 70 exists) and a region 71 that does not emit visible light strongly. When the region where the material 70 exists has a strip shape extending toward the paper surface of FIG. 17, the region of the waveguide 64 that emits visible light has a size, a shape, and a position that are transparent to the parallax barrier 3 of FIG. 15. The region of the waveguide 64 that corresponds to the region 10 and does not emit visible light corresponds to the opaque region of the parallax barrier 3 in FIG. 15 in size, shape, and position. Accordingly, the display backlight 66 of FIG. 16 combines the functions of the conventional backlight of the display of FIG. 15 and the parallax optic 3, the display operates in a directional mode, and the second lens array 61 is It can be thought of as imaging a parallax optical element. The separation between the image of the parallax optical element and the image display layer is smaller than the separation between the parallax optical element and the image display layer, thereby obtaining the advantages described above.

  Material 70 may be provided on the front surface 67 of the waveguide and / or the rear surface 68 of the waveguide. Suitable fluorescent strips for use as material 70 are described in co-pending UK Patent Application No. 0401064.1, the contents of which are incorporated herein by reference.

  The material 70 provided in the waveguide 67 in the embodiment of FIG. 17 is not limited to a fluorescent material, but may alternatively be a phosphorescent material, for example.

  The display 63 ″ can be easily switched from the 2D display mode to the directional display mode. This can be operated in 2D mode by switching on the visible light source 65b and switching off the other light source 65a, or switching off the visible light source 65b and the other light source 65a. Can be operated in directional mode by turning on.

  FIG. 18 is a cross-sectional plan view of a further display 72 of the present invention. The display 72 corresponds in several respects to the display 63 of FIG. 15, and therefore only the differences are described.

  In the display 72 of FIG. 18, the parallax barrier 3 of FIG. 15 and a separate backlight are not present. Instead, the display 72 is provided with or illuminated by a backlight 73 that emits collimated light, preferably collimated along the axis of the display 72.

  In the display 72 of FIG. 18, the first imaging means 60 of the display of FIG. 15 does not exist. Instead, a light directing element 60 'is provided for directing collimated light from the backlight, generally toward the right or left viewing window. Further, the light directivity element and the second imaging means 61 are arranged such that the light directed to the right observation window passes through the pixel columns C1, C3, C5, etc. that display the right image, and the left that displays the left image. Light directed to the observation window is configured to pass through pixel columns C2, C4, C6, and the like. Accordingly, the display of FIG. 18 has improved brightness as already described with reference to display 63 of FIG.

In the embodiment of FIG. 18, the light directing element 60 ′ is an array of prisms extending toward the plane of FIG. It is preferable that the prism array pitch P _p is approximately twice the pixel pitch of the image display layer 4. Light entering one surface 76 of the prism array is directed toward one or more elements of the lens array 61, and each element of the lens array 61 focuses the light toward a respective pixel. The light can be focused at point 77 in the plane of the pixel or at a point 77 in the plane between the lens array and the plane of pixel 4.

The point 77 where the light from the backlight is focused functions as a light transmissive slit. The area between points 77 is dark. The angular separation between the left image and the right image is determined by the separation S _v between the plane of the point 77 and the image display layer 4. This embodiment thus makes it possible to achieve a wide angular separation between views, while making both the substrate 5 and the substrate 75 of the imaging means relatively thick and robust. The substrates 5, 75 can have a thickness of about 0.5 mm, for example.

  The light directing element is not limited to the prism array, and may alternatively be constituted by, for example, a lenticular lens array.

  In the embodiment of FIG. 18, the light directing element 60 ′ and the second imaging means 61 are shown having a common light transmissive substrate 62. Alternatively, the light directing element 60 'and the second imaging means 61 can have separate substrates.

  In a preferred embodiment, the backlight 73 is switchable between a collimation mode in which the backlight emits collimated light and a non-collimation mode in which the backlight emits non-collimated light. If the backlight emits non-collimated light, the light directing element cannot direct light only to the left and right viewing windows, and the display operates in a conventional 2D mode. Thus, in this preferred embodiment, the display 72 of FIG. 18 can be operated in a 2D display mode or a directional display mode by configuring the backlight to emit non-collimated light or collimated light, respectively. This can be done by providing a switchable diffuser in front of the backlight 73. As described above, when the diffuser is switched off, the collimation of the backlight is maintained and the directional display mode is acquired. When the diffuser is switched on, the backlight collimation is destroyed and the 2D display mode is acquired.

  FIG. 19 is a cross-sectional plan view of a further display 72 'of the present invention. As in the embodiment of FIG. 18, the display 72 ′ of this embodiment is provided with a backlight 73 that emits light that is collimated, preferably collimated along the axis of the display 72 ′, or , Illuminated by this backlight.

  Imaging means 74 is provided to focus the light from the backlight 73. The imaging means 74 focuses the light from the backlight 73 on a plurality of laterally separated points 77 disposed between the backlight 73 and the image display layer 4. In the display of FIG. 19, the imaging means is formed by a lenticular lens array formed on a light transmissive substrate 75. Each lens of each lenticular lens array has a pixel column C1. . . Extends substantially parallel to C6 and focuses light from each region of the backlight to one of the points 76.

The point 77 where the light from the backlight is focused functions as a light transmissive slit. The area between points 77 is dark. The angular separation between the left image and the right image is determined by the separation S _v between the plane of the point 77 and the image display layer 4. This embodiment thus makes it possible to achieve a wide angular separation between the views, while making both the substrate 5 and the substrate 75 of the imaging means thick and robust, respectively. The substrates 5, 75 can have a thickness of about 0.5 mm, for example.

  FIG. 19 shows that the point 77 where the light from the backlight is focused is located between the backlight 73 and the image display layer 4. The point 77 where the light from the backlight is focused may alternatively be located on the opposite side of the image display layer 4 with respect to the backlight 73. If the points 77 where the light from the backlight is focused are located on the opposite side of the image display layer 4 with respect to the backlight 73, these points may be in another substrate of the display, or the display And the viewer (in a manner similar to the parallax barrier image 30 ′ of FIG. 6). Pixels shown to be assigned to the left image in FIG. 19 refer to FIG. 6 when the point 77 where the light from the backlight is focused is located on the opposite side of the image display layer 4 with respect to the backlight 73. Assigned to the right image, and vice versa.

  In a preferred embodiment, the lateral pitch of the imaging means is made approximately twice the pixel pitch of the image display layer. In this preferred embodiment, the pixel column displaying the left (or right) image is mainly illuminated by light directed to the left (or right), thus the image mixing zone of the display 72 'is smaller, In addition, the observation window has the advantage of being brighter.

  In a further preferred embodiment, the backlight 73 of the display 72 ′ of FIG. 19 switches between a collimation mode in which the backlight emits collimated light and a non-collimated mode in which the backlight emits non-collimated light. Is possible. If the backlight emits non-collimated light, the imaging means 74 cannot focus the light from the backlight to point 76 and the display operates in a conventional 2D mode. Accordingly, in this preferred embodiment, the display 72 'of FIG. 19 can be operated by configuring the backlight to emit non-collimated light or collimated light, respectively, in 2D display mode or directional mode. This can be done by providing a switchable diffuser in front of the backlight 73. When the diffuser is switched off, the backlight collimation is maintained and the directional display mode is acquired as described above. When the diffuser is switched on, the backlight collimation is destroyed and the 2D display mode is acquired.

  Although FIG. 19 shows a lenticular lens array as the imaging means, the present invention is not limited to this particular type of imaging means. Basically, any convergent diffraction or refractive microstructure (eg, Fresnel lens) can be used in place of a regular lens. The imaging means can further be formed using holographic optical elements.

  In the embodiment of FIGS. 15 to 19, each lens array 60, 61, 61 ′ may or may not be integrated with the substrate 62. If the lens arrays 60, 61, 61 ′ are not integrated with the substrate 62, the refractive index of the lens array may be the same as or different from the refractive index of the substrate 62. The substrate 62 may be a glass substrate, for example.

  In the embodiment of FIGS. 15-19, the imaging means 60, 60 ′, 61 (such as the lens or prism layer shown in the figure) use an adhesive on the substrate 5 of the image display panel and / or on the backlight 73. Can be attached. The adhesive preferably has a refractive index much smaller than that of the lens or prism layer material. The lens or prism can be made from any suitable material, such as, for example, glass or plastic material.

The above-described embodiments are described as incorporating a standard form of parallax barrier in which the slits are repeated throughout the barrier. Co-pending UK patent applications 0228644.1, 0306516.6 and 0315170.1 disclose displays where the parallax barrier is a non-standard form. For example, copending application No. 0306516.6 discloses a parallax barrier in which a group of slits spaced apart by separation between groups is repeatedly arranged, and each group of slits is separated between groups. Spaced by smaller intra-group separation. Such non-standard parallax barriers are incorporated into embodiments of the present invention by ensuring that the parallax optic and the imaging means work together to produce an image of the desired non-standard form of parallax optic. Can be. This includes (a) having a non-standard design parallax optic 3 combined with a uniform lens array 29, as described above, and (b) the above-mentioned standard combined with a non-standard lens array 29. (Where the non-standard lens array 29 can be appropriately patterned and the lens is not necessarily cylindrical, not necessarily straight, or includes an opaque patch on the lens surface) Or (c) by having both a non-standard parallax optic 3 and a non-standard lens array 29.

  In any of the above embodiments that include a lens array, the lens array may be an array of GRIN (Graded Index) lenses.

  FIG. 20 shows a modification of the backlight of the display 63 ′ in FIG. 16. The backlight of FIG. 20 includes a first waveguide 94 and one or more first light sources 95 disposed along the side of the first waveguide. In FIG. 20, two first light sources 95 are shown disposed along opposing sides 94a and 94b of the first waveguide, but the present invention is limited to this particular configuration. Alternatively, only one light source or more than two light sources may be provided. The light source 95 preferably extends over all or substantially all of the respective sides of the first waveguide, and may be, for example, a fluorescent tube.

  A diffusion dot is provided in a selected region 84 of the back surface 94c of the first waveguide 94. The region 84 with the diffusing dots is, for example, in the form of a stripe and can extend toward the paper surface of FIG. When light propagating through the first waveguide is incident on the region 84 where the diffusion dots are provided on the front surface 94c of the waveguide, the light is not reflected by a mirror but is reflected by the above-described figure. As described with reference to FIG. 16, it is scattered outside the first waveguide (in FIG. 20, the observer is assumed to be on the page and the light is 94, scattered generally upwards).

  The backlight further includes a second waveguide 94 'and one or more second light sources 95' disposed along the side of the first waveguide. The second waveguide 94 ′ is disposed behind and is generally parallel to the first waveguide 94. The second waveguide 94 'substantially corresponds to the first waveguide 94 in terms of size and shape. In FIG. 20, two second light sources 95 ′ are disposed along opposite side surfaces 94a ′ and 94b ′ of the second waveguide 94 ′, but the present invention is limited to this particular configuration. Instead, only one second light source or more than two may be used. The light source 95 'preferably extends along all or substantially all of the respective sides of the second waveguide, and may be, for example, a fluorescent tube.

  A diffusing dot 89 is provided over substantially all of the front surface 94d 'of the second waveguide 94'. Thus, when the second light source 95 'is illuminated, the light is scattered outside the front surface 94d' over most of the area of the front surface 94d 'of the second waveguide.

  Therefore, the backlight of FIG. 20 can be switched between the “pattern mode” and the “uniform mode”. In the “pattern mode”, the first light source 95 is irradiated and the second light source 95 ′ is not irradiated. Light propagates only through the first waveguide 94, and the backlight has areas that emit light (these areas correspond to areas 84 with diffused dots) and areas that do not emit light ( These areas correspond to areas without diffusing dots). In “uniform mode”, the second light source 95 ′ is illuminated and light propagates through the second waveguide. Since the diffusing dots 89 are provided over substantially the entire front surface 94d 'of the second waveguide 94', the backlight provides substantially uniform illumination over the entire area in "uniform mode". To do. The display provided with the backlight of FIG. 20 can be switched from the directional display mode to the conventional 2-D display mode by switching the backlight from the “pattern mode” to the “uniform mode”.

In the “uniform mode”, the first light source 95 may or may not be irradiated. If desired, the first light source may be kept on continuously, and the backlight may be switched to a “uniform mode” or a second light source 95 ′ by switching it on or off, respectively. One of the “pattern modes” is set. (Maintaining the patterned waveguide to be illuminated in a uniform mode can cause some variation in intensity across the area of the backlight, but in some applications, this potential disadvantage The need to switch only the second light source 95 'can be important.)
In order to ensure that internal reflection occurs at the back surface 94c of the first waveguide, the space between the first waveguide 94 and the second waveguide 94 'is the first. It is necessary to have a refractive index lower than that of the waveguide. This may be conveniently achieved by providing an air gap between the first waveguide 94 and the second waveguide 94 ', or alternatively, the first waveguide 94 and the second waveguide 94'. The space between the waveguide 94 'and the waveguide 94' may be filled with a light transmissive material having a low refractive index.

The back surface of the region 84 where the diffusing dots are provided on the first waveguide 94 may be made reflective, for example by applying a metal coating. When this is done, any light scattered by the diffusing dots toward the second waveguide 94 'is reflected back toward the viewer. (When the back surface of the region 84 where the diffusion dots are provided on the first waveguide 94 is made reflective, the reflection surface can block the light scattered upward from the second waveguide 94 '. Thus, the first light source and the second light source are illuminated to achieve a uniform mode.)
Each waveguide may be provided with an anti-reflective coating (not shown).

  FIG. 21 shows another backlight according to the present invention. The backlight includes a waveguide 94 and one or more light sources 95 disposed along the side of the waveguide. FIG. 21 shows two light sources 95 arranged along the opposite side surfaces 94a and 94b of the waveguide 94, but the present invention is not limited to this particular configuration, and the light sources used are There may be only one or more than two. The light source 95 preferably extends along all or substantially all of the respective sides of the waveguide, and may be, for example, a fluorescent tube.

  Waveguide 94 includes a layer 87 of liquid crystal material sandwiched between two light transmissive substrates 92 and 93. The liquid crystal layer can be addressed, for example, by electrodes (not shown) that allow an electric field to be applied across the liquid crystal layer 87. The regions 87A and 87B of the liquid crystal layer (shown by dashed lines in FIG. 21) depend on each other, for example, by using appropriately patterned electrodes that allow an electric field to be applied across selected regions of the liquid crystal layer. Addressable without. The regions 87A and 87B of the liquid crystal layer are, for example, in the form of stripes and can extend toward the paper surface of FIG.

  The regions 87A and 87B of the liquid crystal layer can be switched to a scattering mode or a clear light transmission mode. If all liquid crystal regions are switched to the light transmissive mode, light propagates through the waveguide with minimal scattering. That is, light undergoes internal reflection on the upper surface 92 a of the upper substrate 92, passes through the upper substrate 92 and the liquid crystal layer 87 toward the lower substrate 93, undergoes internal reflection on the bottom surface 93 b of the lower substrate 93, and is reflected on the upper substrate 92. Reflects back toward you. There is little or no light emitted from the waveguide.

  In order to emit light from the waveguide, one or more liquid crystal regions are switched to form a region schematically indicated by reference numeral 85 in FIG. When light propagating in the first waveguide enters the scattering region 85, the light is scattered outside the waveguide as described with reference to FIG. 16 above (in FIG. One is assumed to be on the page and light is scattered outside the waveguide 94, generally upwards).

  FIG. 21 shows a waveguide that has been switched so that all of the alternating liquid crystal regions 87 A produce a scattering region 85. The other liquid crystal region 87B is switched so as not to be scattered. The light is emitted only from a region substantially corresponding to the scattering region 85 on the front surface of the waveguide 94, and the backlight operates in the “pattern mode”.

  When all the liquid crystal regions 87A and 87B are switched to form a scattering region, the liquid crystal layer 87 scatters light over the entire region and light is emitted from substantially the entire region of the waveguide 94. It becomes like this. Thus, the backlight operates in “uniform mode” when all the liquid crystal regions 87A and 87B are switched to form a scattering region. The backlight can be switched between “pattern mode” and “uniform mode” by switching the liquid crystal region. The display provided with the backlight of FIG. 21 can be switched from the directional display mode to the conventional 2-D display mode by switching the backlight from the “pattern mode” to the “uniform mode”.

  In the embodiment of the backlight of FIG. 21, the back surface 92b of the upper substrate 92 is smooth throughout its area. In this embodiment, layer 87 needs to include a liquid crystal material that can be switched between a light transmitting state and a light scattering state without significant scattering, such as a polymer dispersed liquid crystal (PDLC). is there. The scattering region 85 is obtained by switching the region of the liquid crystal layer to the scattering mode.

  For example, the region 87A of the liquid crystal layer is switched to the scattering mode so as to generate the scattering region 85. The light passing from the upper substrate 92 to the region 87A of the liquid crystal layer is scattered by the liquid crystal material, and a part of the light is reflected upward and can pass from the front surface of the waveguide 94 to the outside. Conversely, the region 87B of the liquid crystal layer is switched to a mode that does not scatter. The light passing from the upper substrate 92 to the region 87B of the liquid crystal layer only passes to the lower substrate without being scattered by the liquid crystal. When the region 87B of the liquid crystal layer is in a mode that does not scatter, the backlight is in the “pattern mode”.

  In order to achieve a “uniform mode” of the backlight, all of the regions 87A and 87B of the liquid crystal layer are switched to the scattering mode. The back surface of the waveguide 94 scatters over substantially the entire area.

  In this embodiment, it is possible to change the size and position of the scattering region 85 and the non-scattering region. For example, two adjacent liquid crystal regions are switched to the scattering mode, the next liquid crystal region to the non-scattering mode, the next two liquid crystal regions to the scattering mode, and the next liquid crystal region to the non-scattering mode. It is possible to simulate a parallax barrier having an aperture to barrier ratio of

  Alternatively, the areas of the back surface 92b of the upper substrate 92 that correspond to the desired position of the scattering area 85 may be roughened so that these areas always scatter light. The backlight can be switched between “uniform mode” and “pattern mode” by switching the liquid crystal region 87B to a scattering mode or a non-scattering mode, respectively.

  As yet another example, the upper substrate back surface 92b may be optically rough throughout its area. This embodiment requires that the layer 87 of liquid crystal material has a refractive index that can be changed. The scattering region 85 is obtained by switching the corresponding liquid crystal region 87A so that the refractive index of the liquid crystal does not match the refractive index of the waveguide 94. Light propagating through the upper substrate “sees” and scatters the optically rough surface on the upper surface of the upper substrate.

  The non-scattering region is obtained by switching the corresponding liquid crystal region 87B so that the refractive index of the liquid crystal in the region 87B matches the refractive index of the upper substrate 92. The light propagating through the upper substrate does not “see” the optically rough surface and passes through the liquid crystal layer without being scattered (then it is internally reflected at the back surface 93b of the lower substrate).

  The reflective surface may be provided behind the scattering region 85 if the position of the scattering region is fixed, which is indicated by reference numeral 86 in FIG. Any light scattered toward the back surface 93 by the scattering region 85 is reflected by the reflecting surface 86 toward the viewer.

  FIG. 22 shows a further backlight. The backlight includes a waveguide 94 and one or more light sources 95 disposed along the side of the waveguide. In FIG. 22, two light sources 95 are shown disposed along opposing sides 94a and 94b of the waveguide 94, but the invention is not limited to this particular configuration and the light sources used are There may be only one or more than two. The light source 95 preferably extends along all or substantially all of the respective sides of the waveguide, and may be, for example, a fluorescent tube.

  Diffusion dots are provided in selected areas of the back surface 94c of the waveguide 94. The region 84 with the diffusing dots is, for example, in the form of a stripe and can extend toward the paper surface of FIG. When light propagating through the first waveguide is incident on the region 84 where the diffusion dots are provided on the front surface 94c of the waveguide, the light is not reflected by a mirror but is reflected by the above-described figure. As described with reference to FIG. 16, it is scattered outside the first waveguide (in FIG. 22, it is assumed that the observer is on the page and the light is 94, scattered generally upwards).

  The lens array 88 is disposed on the front surface of the waveguide 94. The lens array directs light emitted by the waveguide 94 primarily in a first direction (or first range of directions) 90 and a second direction (or second range of directions) 91. The first direction (or first range of directions) 90 and the second direction (or second range of directions) 91 are preferably separated by a third range of directions including the vertical direction. Since light is primarily directed in the first and second directions (or first and second ranges of directions) 90 and 91, the first and second directions (or first and second directions) The intensity of the light in the ranges 90 and 91 is higher than the intensity in the third range of directions. A first direction (or first range of directions) 90 and a second direction (or second range of directions) 91 are each on opposite sides in the vertical direction and are substantially symmetrical with respect to the normal. Preferably there is.

  The backlight of FIG. 22 is particularly suitable for use in a directional display. A typical dual view display displays two images, for example, in a state where images are displayed along a direction on the opposite side in the vertical direction. The backlight of FIG. 22 provides a bright image by directing light primarily in the direction in which the two images are displayed by the dual view display. In contrast, conventional backlights have the highest brightness along the vertical direction and have lower brightness when viewed from off-axis directions.

  A four-view illumination system can be made by using a 2D array of microlenses and a 2D array of diffusing dots. This provides four views arranged so that there are two views above the two views, providing both horizontal and vertical spacing of the views.

  FIG. 23 shows a further backlight. This backlight is similar to the backlight of FIG. 22 in that a lens array is provided that directs emitted light in two preferred directions (or range of directions) 90 and 91. The backlight of FIG. 23 further includes a second waveguide 94 'and a second light source 95' disposed along each side of the second waveguide 94 '. The diffusion dots 89 are provided over substantially the entire front surface of the second waveguide 94 '. The second waveguide 94 'in FIG. 23 substantially corresponds to the second waveguide 94' in FIG. The backlight of FIG. 23 can be switched between “pattern mode” and “uniform mode” in the manner described above with respect to the backlight of FIG.

  The backlights of FIGS. 20-23 can be incorporated into the display 63 'of FIG. 16 or the display 63' 'of FIG. 17, for example.

  In the embodiment of FIGS. 20-23, the density of the diffusing dots is reduced to compensate for the spatial illumination uniformity to compensate for the intensity of light propagating in the waveguide, which decreases as the distance from the light source 95 increases. Can be adjusted to. This can be applied to both the waveguides of the embodiments of FIGS.

  In the embodiments of FIGS. 20-23, the diffusing dots can be replaced with fine reflective structures such as prisms, protrusions and the like. This can be used, for example, by controlling the radiation direction from the region of the waveguide where the diffusing dots are provided.

  While the above-described embodiments may be varied in many ways, they may still remain within the scope of the appended claims. Possible variations include, but are not limited to, the following variations.

  In all embodiments where an imaging means formed of a single lens array is provided, the imaging means may alternatively be constituted by a group array of real lenses. An effective equivalent of this real lens is a single lens array having the same effective focal length at the location specified for the imaging means in this embodiment.

  In all of the above embodiments where the imaging means images the parallax optical element, the display may comprise a plurality of parallax optical elements. As described above, the first parallax optical element is imaged by the imaging means. Other parallax optical elements can be provided to modify the light to improve crosstalk or eliminate the secondary viewing window. By providing a secondary parallax optical element, for example, the problem described in FIG. 7B is solved. Secondary optical elements can be used in conjunction with other techniques described above to reduce crosstalk or secondary observation windows.

  The display described above displays two views. However, any of the described embodiments are not limited to displaying just two views, and more than two views may be displayed. Furthermore, while the above-described display provides a laterally separated viewing window, the present invention provides a vertically separated viewing window or a laterally separated viewing window and a vertically It can also be applied to displays that provide both separate viewing windows.

  The imaging means of the display of FIG. 9D can alternatively be formed with three lens arrays in a manner similar to the imaging means of the display of FIG. 9A.

  The display of FIG. 11 may be provided with an opaque flange louver configuration similar to that provided in the secondary window removed and destroyed in the display of FIG. 7F.

As mentioned above, although this invention has been illustrated using preferable embodiment of this invention, this invention should not be limited and limited to this embodiment. It is understood that the scope of the present invention should be construed only by the claims. It is understood that those skilled in the art can implement an equivalent range based on the description of the present invention and the common general technical knowledge from the description of specific preferred embodiments of the present invention. Patents, patent applications, and documents cited herein should be incorporated by reference in their entirety, as if the contents themselves were specifically described herein. Understood.
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A multi-view directional display according to the present invention comprises a parallax optical element (3), a pixelated image display layer (4), and imaging means (29) for imaging one of the parallax optical element and the image display layer. Is provided. The image has a smaller separation between the image and the other of the parallax optic and the image display layer than the separation between the parallax optic and the image display layer, thereby allowing two observations produced by the display. It can be formed to increase the angular separation between windows.

  The imaging means (29) forms an image of the parallax optic, whereby the separation between the image and the image display layer is less than the separation between the parallax optic and the image display layer, or This can increase or decrease the angular separation between the two viewing windows generated by the display.

  The imaging means (29) forms one image of the parallax optical element and the image display layer, whereby the image of the parallax optical element or the image display layer is substantially equal to the pitch of the parallax optical element or the image display layer. Can have a pitch.

FIG. 1 is a schematic plan view of a conventional multi-view directional display. FIG. 2A shows a further prior art directional display. FIG. 2B shows a further prior art directional display. FIG. 3 shows a further prior art directional display. FIG. 4 shows a further prior art directional display. FIG. 5 is a schematic plan sectional view of the directional display according to the first embodiment of the present invention. FIG. 6 shows a modification of the display of FIG. FIG. 7A is a schematic plan cross-sectional view of a directional display according to a further embodiment of the present invention. FIG. 7B is a schematic plan cross-sectional view of a directional display according to a further embodiment of the present invention. FIG. 7C is a schematic plan cross-sectional view of a directional display according to a further embodiment of the present invention. FIG. 7D is a schematic plan cross-sectional view of a directional display according to a further embodiment of the present invention. FIG. 7E is a schematic plan cross-sectional view of a directional display according to a further embodiment of the present invention. FIG. 7F is a schematic plan cross-sectional view of a directional display according to a further embodiment of the present invention. FIG. 7G is a schematic plan cross-sectional view of a directional display according to a further embodiment of the present invention. FIG. 7H is a schematic plan cross-sectional view of a directional display according to a further embodiment of the present invention. FIG. 7I is a schematic plan cross-sectional view of a directional display according to a further embodiment of the present invention. FIG. 8A is a schematic plan cross-sectional view of a display having variable focal length imaging means according to a further embodiment of the present invention. FIG. 8B is a schematic plan cross-sectional view of a directional display according to a further embodiment of the present invention. FIG. 8C is a schematic plan cross-sectional view of a directional display according to a further embodiment of the present invention. FIG. 9A is a schematic plan cross-sectional view of a display having a multi-lens system, according to a further embodiment of the present invention. FIG. 9B is a schematic plan cross-sectional view of a display having two separately controllable lens arrays, according to a further embodiment of the present invention. FIG. 9C is a schematic plan cross-sectional view of a display having a laterally movable parallax barrier or imaging system, according to a further embodiment of the present invention. FIG. 9D is a schematic plan cross-sectional view of a display having a movable parallax barrier and an imaging system, according to a further embodiment of the present invention. FIG. 10 is a schematic plan cross-sectional view of a display according to a further embodiment of the present invention. FIG. 11 is a schematic plan cross-sectional view of a display according to a further embodiment of the present invention. FIG. 12 is a schematic plan cross-sectional view of a display according to a further embodiment of the present invention. FIG. 13A is a schematic plan cross-sectional view of a display according to a further embodiment of the present invention. FIG. 13B is a schematic plan cross-sectional view of a display according to a further embodiment of the present invention. FIG. 14 is a schematic plan cross-sectional view of a display according to a further embodiment of the present invention. FIG. 15 is a schematic plan cross-sectional view of a display according to a further embodiment of the present invention. FIG. 16 is a schematic plan cross-sectional view of a display according to a further embodiment of the present invention. FIG. 17 is a schematic plan cross-sectional view of a display according to a further embodiment of the present invention. FIG. 18 is a schematic plan cross-sectional view of a display according to a further embodiment of the present invention. FIG. 19 is a schematic plan cross-sectional view of a display according to a further embodiment of the present invention. FIG. 20 is a diagram showing a backlight suitable for use in the display of the present invention. FIG. 21 is a diagram showing a further backlight suitable for use in the display of the present invention. FIG. 22 is a diagram showing a further backlight suitable for use in the display of the present invention. FIG. 23 shows a further backlight suitable for use in the display of the present invention.

Explanation of symbols

2 image display element 3 parallax optical element 4 image display layer 5 first light transmissive substrate 6 second light transmissive substrate 7 backlight 8 first polarizer 9 second polarizer 10 light transmissive slit 10 ′ Image of transmissive slit 12 First light transmissive substrate 12 ′ Second light transmissive substrate 13 Left observation window 14 Right observation window 28 Multi-view directional display 29 Lenticular lens array

Claims (34)

A multi-view directional display,
A parallax optical element (3);
A pixelated image display layer (4);
The separation distance between one image of the parallax optical element and the image display layer and the other of the parallax optical element and the image display layer is greater than the separation distance between the parallax optical element and the image display layer. Image one of the parallax optic (3) and the image display layer (4) such that the angular separation between the two viewing windows (13, 14) generated by the display is also reduced Imaging means (29; 29 ′; 39; 43, 44, 45; 47, 48; 61),
A first tracking means for determining a distance between the display and the observer, and at least one tracking means (41) of a second tracking means for determining a lateral position of the observer with respect to the display; Prepared,
A first control that controls the focal length of the imaging means in accordance with the distance determined by the first tracking means; and an observer whose lateral position of the imaging means is determined by the second tracking means. A multi-view directional display that performs at least one of the second controls that are controlled in accordance with the position in the horizontal direction . A multi-view directional display,
A parallax optical element (3);
A pixelated image display layer (4);
The separation distance between the image (30, 30 ′) of the parallax optical element (3) and the image display layer (4) is the separation distance between the parallax optical element (3) and the image display layer (4). Image the parallax optic (3) to be smaller or larger than this, thereby increasing or decreasing the angular separation between the two viewing windows (13, 14) generated by the display, respectively Imaging means (29; 29 ′; 39; 43, 44, 45; 47, 48; 61);
First tracking means for determining a distance between the display and an observer, and at least one tracking means for determining a lateral position of the observer with respect to the display;
A first control that controls the focal length of the imaging means in accordance with the distance determined by the first tracking means; and an observer whose lateral position of the imaging means is determined by the second tracking means. A multi-view directional display that performs at least one of the second controls that are controlled in accordance with the position in the horizontal direction .   The imaging means is configured to generate an image of the parallax optic or image display layer having a pitch substantially equal to the pitch of the parallax optic or image display layer. Display.   The parallax optical element (3) is disposed behind the image display layer (4), the imaging means is disposed between the parallax optical element (3) and the image display layer (4), and 4. A display as claimed in any one of the preceding claims, which, in use, forms an image (30, 30 ') of the parallax optic (3).   The image display layer (4) is disposed behind the parallax optical element (3), the imaging means is disposed between the image display layer (4) and the parallax optical element (3), and The display according to claim 1, wherein an image of the image display layer is formed during use.   The imaging means is configured to generate an image of an element of the parallax optical element or a pixel of the image display layer having a width substantially equal to a width of the element of the parallax optical element or the pixel of the image display layer. The display according to claim 1.   The imaging means is configured to generate an image of the parallax optic element or the image display layer pixel having a width greater than the parallax optic element or pixel width of the image display layer pixel. The display according to claim 1.   The imaging means generates an image of the elements of the parallax optic or pixels of the image display layer having a width that is substantially an integer multiple of the width of the elements of the parallax optic or pixels of the image display layer. The display according to claim 7, which is configured as follows.   The imaging means is configured to generate an image of a parallax optic element or an element of the parallax optic element having a width smaller than a width of the image display layer or a pixel of the image display layer. The display in any one of.   The imaging means outputs an image of the parallax optic element or the image display layer pixel having a width substantially equal to the width of the parallax optic element or the image display layer pixel divided by the integer. The display of claim 9, wherein the display is configured to generate.   11. A display according to claim 9 or 10, further comprising blocking means for blocking an image of one or more elements of the parallax optic.   12. A display according to claim 11, wherein the blocking means comprises a plurality of opaque regions extending between the imaging means and one of the parallax optic and the image display layer.   13. A display according to any preceding claim, comprising a diffuser layer, the diffuser layer being positioned to substantially coincide with the image plane of the parallax optic or the image display layer.   The display according to claim 1, wherein the imaging means has a variable focal length.   15. A display according to claim 14, comprising a controller for controlling the focal length of the imaging means.   A first tracking means for determining a distance between the display and the observer, wherein the controller receives an output from the tracking means during use, whereby the display and the observer; 16. The display of claim 15, wherein the focal length of the imaging means is controlled based on the distance between the imaging means and the display.   The display according to claim 1, wherein the imaging means has a variable focal length and a variable magnification.   18. A display according to claim 17, comprising a controller for controlling the focal length and magnification of the imaging means.   The display according to any one of claims 14 to 18, further comprising a diffuser layer.   The display according to claim 1, wherein the imaging means comprises a lens array.   The imaging means comprises first and second disabling lens arrays, the first lens array being offset laterally with respect to the second lens array, the display comprising: 14. A controller according to any of claims 1 to 13, comprising a controller for disabling the other of the first and second lens arrays while enabling the first lens array or the second lens array. Display as described in.   The display according to any one of claims 1 to 21, wherein the imaging means is movable in a lateral direction with respect to one of the parallax optical element and the image display layer.   23. A display as claimed in claim 21 or 22, comprising second tracking means for determining an observer lateral position relative to the display.   22. A second tracking means for determining an observer's lateral position relative to the display, wherein the controller receives an output from the second tracking means during use. Display.   A second tracking means for determining a lateral position of an observer with respect to the display, wherein the lateral position of the imaging means with respect to one of the parallax optical element and the image display layer is the second position; 23. A display as claimed in claim 22, controlled based on the output from the tracking means.   26. A display as claimed in any of claims 16 to 25, further comprising means for identifying an observer of the display.   The imaging unit according to claim 1, wherein the imaging unit is fixed with respect to one of the parallax optical element and the image display layer and is movable with respect to the other of the parallax optical element and the image display layer. Display as described in.   The imaging means generates an image of the parallax optic or image display layer that is laterally offset with respect to the image display layer or the parallax optic, whereby the display is in first use. And the second image, wherein the angular spread of the first image is different from the angular spread of the second image, and is configured to display the first image and the second image. The display according to claim 1.   The display according to any one of claims 1 to 20, wherein the imaging means is an asymmetric imaging means.   30. Each element of the imaging means comprises a first portion having a first focal length and a second portion having a second focal length different from the first focal length. Display as described.   The display according to any one of claims 1 to 30, wherein the imaging means is configured so that an image on the parallax optical element or the image display layer is a virtual image.   The display according to claim 1, wherein the parallax optical element or the image display layer generates an image of the parallax optical element or the image display layer having a non-uniform pitch in cooperation with the imaging unit.   The parallax optical element or the image display layer is linked with the imaging unit, and the parallax optical element or the image display layer displays an image of the parallax optical element or the image display layer with respect to the parallax optical element or the image display layer. 35. A display as claimed in any of claims 1 to 32, which is produced on the other opposite side of the layer.   The display according to any one of claims 1 to 33, wherein the parallax optical element or the image display layer generates an image of the parallax optical element or the image display layer outside the display in cooperation with the imaging layer.

Images