TWI611216B - 2d/3d mode-switchable electronic display and method with dual layer backlight - Google Patents

Abstract

The present invention provides a dual layer backlight panel comprising a first planar backlight for emitting light and a second planar backlight for providing a plurality of coupled beams. The second planar backlight panel has a flat light guide body and a multi-beam diffraction grating, and the multi-beam diffraction grating system couples a part of the light guide beam in the flat light guide body into a plurality of coupled light beams. . One of the beams that are coupled out of the beam has a major angular direction that is different from the other of the coupled beams. The present invention also provides a two-dimensional/three-dimensional mode switching electronic display comprising the above-described dual-layer backlight panel and a light valve array, the light valve array being selectively emitted in the first mode of the electronic display The light strips become two-dimensional pixels, and in the second mode of the electronic display, the coupled out beams are modulated into voxels corresponding to different three-dimensional views.

Description

Two-dimensional/three-dimensional mode switching electronic display and method with double-layer backlight board

The present invention pertains to a backlight panel; in particular, a dual layer backlight panel and a two-dimensional/three-dimensional mode switching electronic display using the same.

For users of a wide range of devices and products, electronic displays are an almost ubiquitous medium for disseminating information to users. The most common electronic displays are cathode ray tube (CRT), plasma display panels (PDP), liquid crystal displays (LCD), and electroluminescent displays (EL). , organic light emitting diodes (OLEDs) and active organic OLEDs (AMOLED) displays, electrophoretic displays (EP), and various electromechanical or electrohydrodynamic modulations A display (eg, a digital micromirror device, an electrowetting display, etc.). In general, an electronic display can be divided into one of an active display (ie, a display that emits light) or a passive display (ie, a display that modulates light provided by another light source). Among the categories of active displays, the most obvious examples are CRTs, PDPs, and OLEDs/AMOLEDs. In the case of the above classification by the emitted light, LCDs and EP displays are generally classified in the classification of passive displays. Passive displays, while often exhibiting attractive performance characteristics including, but not limited to, inherent low power consumption, may have limitations in use in many practical applications due to their lack of illuminating capabilities.

To overcome the use limitations associated with passive displays and emitted light, many passive displays are coupled to an external source. Coupled light sources can make these passive displays The indicators illuminate and make these passive displays essentially function as active displays. The backlight panel is one of the examples of such a coupled light source. A backlight is a light source (usually a panel light source) placed behind a passive display to illuminate a passive display. For example, the backlight can be coupled to an LCD or EP display. The backlight will emit light that can pass through the LCD or EP display. The emitted light emitted will be modulated by the LCD or EP display, and the modulated light will then be sequentially emitted by the LCD or EP display. Usually the backlight panel emits white light. The color filter then converts the white light into light of various colors used in the display. For example, the color filter can be placed at the output of the LCD or EP display (less common configuration) or can be placed between the backlight and the LCD or EP display.

The following embodiments and examples provide an information display that supports switching between two-dimensional information and display of three-dimensional information in accordance with the principles of the present invention. In particular, according to principles consistent with the present invention, information can be selectively displayed in a two-dimensional mode or a three-dimensional mode. The 3D mode can be used to display images or other similar information with a "naked eye" or naked eye 3D stereo display, while the 2D mode can be used to display information that lacks a third dimension or at least does not benefit from the third dimension (eg, text, two Information such as dimensional images). Moreover, according to various examples that are identical to the principles described herein, the switchable two-dimensional and three-dimensional modes are provided on the same display unit or system. Compared with a display system using only a two-dimensional display or a three-dimensional display, a switchable display system capable of selectively displaying two-dimensional information and three-dimensional information on the same display system can make a single display system conform to a wider range. And different data display needs.

According to various embodiments, the present invention provides a two-layer backlight panel that can be switched between modes for displaying two-dimensional information and three-dimensional information. More specifically, the first layer of the dual layer backlight provides light for providing or displaying two-dimensional information. The second layer of the dual-layer backlight panel supports the display of three-dimensional information by emitting a plurality of light beams corresponding to predetermined main angular directions of respective three-dimensional viewing angles. According to various embodiments of the invention, the first layer of the dual layer backlight panel may comprise substantially any planar backlight board. In accordance with various embodiments of the present invention, the second layer of the dual layer backlight panel includes a light guide and a multi-beam diffraction grating to produce a coupled beam of the beams.

As used herein, "light guide" is defined as a structure that uses total internal reflection to direct light in its structure. In particular, the light guide can include a core that is substantially transparent at the operating wavelength of the light guide. In various embodiments, the term "light guide" generally refers to a dielectric optical waveguide that utilizes a substance that totally reflects the dielectric of the light guide and a substance or medium that surrounds the light guide. The interface between the guides the light. By definition, the condition of total internal reflection is that the refractive index of the light guide is greater than the refractive index of the surrounding medium adjacent to the surface of the light guide body. In some embodiments, the light guide may additionally include a coating in addition to the refractive index difference described above, or may replace the aforementioned refractive index difference with a coating, thereby further contributing to total internal reflection. For example, the coating can be a reflective coating. According to various embodiments, the light guide may be any one of several light guides, which may include, but is not limited to, one or both of a flat or thick light guide and a strip of light guides. .

In addition, in this paper, when the term "slab" is applied to a light guide, such as "slab light guide", it is defined as a sheet, a difference plane layer or a sheet, and at a certain In some cases, it is called a "slice" light guide. In particular, a flat light guiding system is defined as a light directing body that directs light in two substantially orthogonal directions defined by the upper and lower surfaces of the light guide (in other words, the two opposing surfaces). Moreover, in the definition of the present specification, the upper surface and the lower surface are spaced apart from each other, and according to some embodiments of the present invention, both are surfaces that are substantially parallel to each other, at least in the sense of division. That is, in any of the different small areas of the planar light guide, the upper and lower surfaces are substantially parallel or coplanar surfaces.

In other embodiments, the planar light guide may have a wedge shape wherein the space between the upper surface and the lower surface varies as a function of the distance across the planar light guide. In particular, in some embodiments, the space between the upper surface and the lower surface of the wedge shape may be a space that increases with the distance from the input end of the wedge-shaped flat light guide to the output end or terminal. For example, such a wedge-shaped light guide can provide collimation (eg, vertical collimation) of light introduced at the input.

In some examples, a flat light guide can have a substantially flat shape The structure (i.e., confined on one plane) thus makes the planar light guide a planar light guide. In other embodiments, the planar light guide may have a structure that is curved in one or two orthogonal dimensions. For example, the flat light guide may have a curved structure in a single dimension to form a cylindrical flat light guide. However, in various embodiments, any curvature needs to have a sufficiently large radius of curvature to ensure that full internal reflection is maintained in the planar light guide to direct light.

In accordance with various embodiments of the present invention, a diffraction grating (eg, a multi-beam diffraction grating) can be used to break up light or couple light out of a light guide (eg, a flat light guide) And become a beam. Here, a "diffraction grid" is generally defined as a plurality of structural features (i.e., diffractive structural features) for providing diffraction of light incident on the diffraction grating. In some embodiments, the plurality of structural features can be arranged in a periodic or quasi-periodic manner. For example, the diffraction grating can include a plurality of structural features (eg, a plurality of grooves on a surface of a material) disposed in a one-dimensional array. In other examples, the diffraction grating can be a two-dimensional array of construction features. For example, the diffraction grating can be a two-dimensional array of protrusions on the surface of the material.

Thus, as defined in this specification, a diffraction grating is a structure that provides diffraction of light incident on the diffraction grating. If light is incident on a diffraction grating by a light guide, the diffraction or diffraction scattering provided by it may result in and thus may be referred to as "diffraction coupling", which may be diffracted by diffraction. The way couples the light away from the light guide. The diffraction grating also redirects or changes the angle of the light by means of diffraction (ie, at a diffraction angle). In particular, due to diffraction, light exiting the diffraction grating (ie, diffracted light) typically has a different conduction direction than the direction of conduction of light incident on the diffraction grating (ie, incident light). The change in the direction of conduction of light produced by diffraction is referred to herein as "diffuse reorientation." Therefore, the diffraction grating can be understood as a structure having a diffraction characteristic for redirecting light incident on the diffraction grating by means of diffraction, and if the light is emitted by the light guide, the diffraction grating is also Light from the light guide can be coupled in a diffractive manner.

Moreover, as defined in this specification, the features of the diffraction grating are referred to as "diffractive structural features" and may be located on a surface, within a surface, or on a surface (in other words, "surface Refers to one between two materials More than one diffraction structure feature of the boundary). The surface may be a surface of a flat light guide. The diffractive structural features can include any kind of light diffractive structure, which can include, but is not limited to, more than one groove, ridge, hole, and protrusion on the surface, in the surface, or on the surface. For example, the diffraction grating can include a plurality of parallel grooves in the surface of the material. In another example, the diffraction grating can include a plurality of parallel ridges that protrude from the surface of the material. The diffractive structural features (whether grooves, ridges, holes, protrusions, etc.) may have any of a variety of cross-sectional shapes or contours that provide a diffractive function, including or not Limited to: one or more of a sinusoidal profile, a rectangular profile (eg, a binary diffraction grating), a triangular profile, and a sawtooth profile (eg, a blazed grating).

According to the definition in this specification, a "multi-beam diffraction grating" is a diffraction grating that produces a beam that is reoriented by diffraction (eg, diffracted light). Further, as defined in the present specification, the beam beams produced by the multi-beam diffraction grating have major angular directions different from each other. More specifically, as defined by the present invention, one of the beams is associated with the beam due to the diffraction coupling of the incident beam and the reorientation of the diffracted beam by the multi-beam diffraction grating. Another predetermined different angular direction of the other beam. The beams can represent a light field. For example, the beams may include eight beams having eight different major angular directions. For example, the combination of the eight beams (ie, the beams) can represent a light field. According to various embodiments of the present invention, the different main angular directions of the respective beams are determined by a combination of two factors, namely grid pitch or spacing, and multi-beam diffraction gratings. The diffractive structure features directionality or rotation at the starting point of each beam relative to the direction of conduction of light incident on the multi-beam diffraction grating.

In accordance with various embodiments described in the present invention, the coupled light produced by the diffraction grating (e.g., multi-beam diffraction grating) represents the pixels of the electronic display. More specifically, the light guide having a multi-beam diffraction grating for generating light beams having different main angular directions may be part of a backlight of an electronic display or may be a backlight used with an electronic display. Part of the electronic display can be, but is not limited to, a "naked eye" three-dimensional electronic display (eg, Also known as a multi-view or holographic display, or a naked-eye 3D stereo display. As described above, the multi-beam diffraction grating can be used to represent the pixels of a three-dimensional electronic display by transmitting light beams having different orientations generated by coupling light out of the light guide. Again, as described above, beams having different orientations can form a light field.

As used herein, a "collimating" mirror is defined as a mirror that has a curved shape and collimates light reflected by the collimating mirror. For example, the reflective surface of the collimating mirror can have the characteristics of a parabolic curve or a parabolic shape. In another example, the collimating mirror can be a parabolic mirror. "Parabolic-like" means that the curved reflecting surface of the parabolic mirror deviates from the "true" parabolic curve to achieve a predetermined reflective characteristic (eg, collimation). In some embodiments, the collimating mirror can be a continuous mirror (ie, having a substantially smooth and continuous reflective surface), while in other embodiments, the mirror can include a Fresnel reflection for providing light collimation. Frensnel reflector or Fresnel mirror. According to various embodiments of the invention, the amount of collimation provided by the collimating mirror may vary between predetermined levels of collimation or collimation depending on different embodiments. Additionally, the collimating mirror can be configured to provide collimation in one or two orthogonal directions (eg, a vertical direction and a horizontal direction). In other words, according to various embodiments of the invention, the collimating mirror may have a parabolic or parabolic shape in one or two orthogonal directions.

As used herein, the term "light source" is defined as the source of light (eg, a device or component that provides and emits light). For example, the light source can be a light emitting diode (LED) that emits light when activated. Here, the light source may be any source of light or light emitter, including but not limited to, more than one LED, a laser, an organic light emitting diode (OLED), a polymer light emitting Diodes, plasma light emitters, fluorescent lamps, incandescent lamps, and any other visually visible source of light. The light produced by the light source may have a color (ie, may have a particular wavelength of light) or may have a range of wavelengths (eg, white light).

In addition, the article "a" used in the specification has the ordinary meaning in the patent field, that is, means "one or more." For example, "a grille" Refers to one or more grilles. More specifically, "the grille" here means "the (etc.) grille." In addition, any "top", "bottom", "upper", "lower", "upper", "lower", "front", "back", "left" or "right" as referred to herein are not intended to be It becomes any limit. As used herein, when applied to a value, unless specifically stated otherwise, the term "about" generally refers to the tolerance of the device used to produce the value, or in some embodiments, plus or minus 10%, or Positive or negative 5%, or plus or minus 1%. Moreover, by way of example, the term "substantially" is used herein to mean a majority, almost all or all, or a value falling within the range of between about 51% and about 100%. Furthermore, the embodiments of the present invention are intended to be illustrative, and are not intended to limit the invention.

100‧‧‧Double-sided backlight

102‧‧‧Light/emitted light/beam/coupled out beam

102a‧‧‧second beam

102b‧‧‧Light

104‧‧‧Light Guide / Guide Beam / Collimated Beam

110‧‧‧First flat backlight

110'‧‧‧ flat light surface

112‧‧‧Light source

114‧‧‧Light guiding structure

116‧‧‧ Drawing structural features

116’‧‧‧Microlayer

116”‧‧·reflective layer

118‧‧‧scatterer

120‧‧‧Second flat backlight

122‧‧‧Slab light guide

124‧‧‧Multi-beam diffraction grating

124a‧‧‧Diffraction structural features

124’‧‧‧ first end

124”‧‧‧second end

126‧‧‧Light source

126a‧‧‧Light emitter

126b‧‧‧ parabolic reflector

130‧‧‧Light barrier

200‧‧‧Electronic display, 2D/3D mode switching electronic display

202‧‧‧Transformed light/modulated emission light

202'‧‧‧ modulated beam

204‧‧‧Light/emitted light

204'‧‧‧coupled out of the beam

210‧‧‧Flat backlight

220‧‧‧Light guide

230‧‧‧Multi-beam diffraction grating

240‧‧‧Light Valve Array

250‧‧‧Light source

300‧‧‧Methods for providing backlights for 2D/3D electronic displays

d ‧‧‧Diagram interval

Θ‧‧‧ angle

‧‧‧方位分量

‧‧‧Azimuth component

‧‧‧方位角

‧‧Azimuth

The various features of the principles described in the specification, which are in the 1A is a cross-sectional view showing an example of a dual-layer backlight panel in accordance with an embodiment consistent with the principles described herein; FIG. 1B is a diagram showing a double layer in accordance with an embodiment consistent with the principles described herein. A cross-sectional view of another example of a backlight panel; FIG. 2 is a cross-sectional view showing an example of a first planar backlight panel in accordance with an embodiment consistent with the principles described herein; FIG. 3A is a diagram in accordance with the present invention An embodiment consistent with the principle of showing a cross-sectional view of an example of a portion of a second planar backlight having a multi-beam diffraction grating; FIG. 3B is an embodiment consistent with the principles described herein, the display having Another example cross-sectional view of a portion of a second planar backlight of a multi-beam diffraction grating; 3C is a perspective view showing an example of a portion of a second planar backlight having a multi-beam diffraction grating in FIG. 3A or FIG. 3B, in accordance with an embodiment consistent with the principles described herein; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 4B is a cross-sectional view showing an example of a portion of a dual-layer backlight panel in accordance with an embodiment consistent with the principles described herein; FIG. 4B is a diagram showing a double layer in accordance with an embodiment consistent with the principles described herein. FIG. 5 is a block diagram showing an example of a two-dimensional/three-dimensional mode switching electronic display according to an embodiment consistent with the principles described herein; and FIG. In accordance with an embodiment consistent with the principles described herein, a flowchart showing an example of a method of providing backlighting for a two-dimensional/three-dimensional electronic display having a two-dimensional/three-dimensional switching mode.

Certain specific examples may have other features that are the same, additional, or can be substituted for features in the above figures. These and other features will be described in detail below with reference to the drawings.

In accordance with the principles described in certain embodiments of the present invention, the present invention provides a dual layer backlight panel. 1A is a cross-sectional view showing an example of a dual-layer backlight panel 100 in accordance with an embodiment consistent with the principles described herein; FIG. 1B is a diagram showing an embodiment in accordance with the principles described in the present invention. A cross-sectional view of another example of the layer backlight 100. In accordance with various embodiments of the present invention, a dual layer backlight 100 is used to provide or emit light 102. More specifically, the dual-layer backlight 100 emits light 102 in a direction substantially away from the dual-layer backlight 100 (eg, away from its surface), as indicated by arrows in FIG. 1A and FIG. Shown. According to various examples and embodiments of the present invention, emitted emitted light 102 can be used for illumination An electronic display of the dual layer backlight 100. Moreover, in some examples and embodiments, an electronic display employing a dual-layer backlight 100 can utilize the emitted emitted light 102 to selectively display a two-dimensional/three-dimensional mode to switch two-dimensional or three-dimensional data or information of the electronic display. One of them, or both data/information.

In more detail, the emitted light 102 of the dual-layer backlight 100 may include one of directional light and scattered light, or both of the above-mentioned two types of light (ie, substantially directional light and substantially scattered light). One or both). The "oriented" emitted light 102 or substantially oriented light may comprise a plurality of beams 102. In contrast, according to the definition in this specification, substantially "scattered" emitted light 102 does not include a plurality of beams 102 and instead has the characteristic of randomly scattered light. In other examples, the "oriented" light 102 emitted from the dual layer backlight 100 can include a plurality of light beams 102 (ie, substantially unidirectional light beams 102) having substantially similar primary angular directions. An example of scattered or unidirectional emitted light 102 is shown in Figure 1A, and an example of emitted light 102 having different predetermined primary angular directions is shown in Figure 1B. In Figure 1A, the emitted light 102 is shown in the form of a dashed arrow whereby the substantially unidirectional or scattered emitted light is separated from the emitted light comprising the beams 102, for example, in solid lines in Figure 1B. The arrows indicate the emitted light of the beams 102. Thus, the emitted light 102 indicated by the dashed arrow in FIG. 1A represents light that is oriented generally toward the direction of the dotted arrow, rather than a light beam that merely represents the direction in which the arrow itself is oriented.

Moreover, in accordance with certain embodiments, the plurality of light beams 102 having different predetermined angular orientations may constitute a light field in the viewing direction of the electronic display employing the dual layer backlight 100. More specifically, a beam 102 of the beams 102 (and in the light field) provided or emitted by the dual layer backlight 100 may have a different angular orientation than the other beams 102 of the beams. . Furthermore, the beam 102 can have a predetermined direction (primary angular direction) and a relatively narrow angular dispersion in the light field. Regarding use in a three-dimensional electronic display, the primary angular direction of the beam 102 can be an angular direction corresponding to a particular viewing angle of the three-dimensional electronic display. As such, in accordance with some examples of the invention, beam 102 may represent or correspond to a pixel of a three-dimensional electronic display associated with a particular viewing angle.

In contrast, the emitted light 102 is scattered light (ie, substantially lacking light of the plurality of beams 102) or is light comprising a plurality of light beams 102 having substantially similar major angular directions (ie, co-directional or unidirectional) In some embodiments of the emitted light beam 102), the emitted light 102 generally does not form a light field. Instead, the scattered emitted light 102 provided by the dual layer backlight 100 provides illumination that is generally omnidirectional in a relatively wide cone angle and oriented away from or away from the dual layer backlight 100 (eg, above). . Similarly, the emitted light 102 of the light beam 102 having a similar orientation provided by the dual layer backlight 100 can represent substantially unidirectional emitted light 102 that is generally perpendicular to the dual layer backlight 100 or perpendicular to its surface. In accordance with various embodiments of the present invention, the scattered light or emitted light 102 comprising a similarly directed beam 102 can be used as a backlight for a two-dimensional electronic display.

In some embodiments, the emitted light 102 produced by the dual layer backlight 100 can be modulated (eg, through a light valve as described below). In particular, modulation of the beam 102 directed toward different angular directions and away from the dual layer backlight 100 is particularly useful in applications of dynamic three-dimensional color electronic displays. In other words, each modulated beam 102 oriented toward a particular viewing angle may represent a dynamic pixel of a three-dimensional electronic display corresponding to a particular viewing angle direction. On the other hand, for example, substantially unidirectional or scattered modulated modulated light 102 can represent dynamic two-dimensional pixels in the application of a two-dimensional electronic display.

As shown in FIGS. 1A-1B, the dual layer backlight panel 100 includes a first planar backlight panel 110. The first planar backlight panel 110 has a planar light emitting surface 110' for providing emitted light 102 (e.g., Figure 1A). According to various embodiments of the present invention, the first planar backlight 110 may be substantially any backlight having a substantially planar light emitting surface 110'. For example, the first planar backlight 110 may be a flat backlight that directly emits or directly illuminates. The planar backlights that are directly emitted or directly illuminated may include, but are not limited to, a planar array of backlights using cold-cathode fluorescent lamps (CCFLs), neon lights, or directly illuminating the planar light emitting surface 110' and providing emitted light 102. Light-emitting diodes (LEDs). An electroluminescent panel (ELP) is another non-limiting example of a directly emitted planar backlight.

In other examples, the first planar backlight panel 110 can include a backlight panel that employs an indirect light source. Such a non-direct illumination backlight may include, but is not limited to, various forms of edge-coupled backlights, or a backlight such as "edge illumination." Edge-lit backlights typically have light sources (not shown in Figures 1A and 1B) that are coupled to the edges or sides of a light guide or similar light directing structure (e.g., a hollow light directing chamber). The edge coupling light source illuminates the light guiding structure, thereby providing light in the edge illumination backlight. For example, edge coupled light sources can include, but are not limited to, CCFLs and LEDs. In accordance with various examples of the invention, the light directing structure can direct light from the edge coupled light source through a complete internal reflection, a mirror (eg, a mirror back), or a combination of both. Moreover, in some examples, the light guiding structure of the edge-illuminated backlight used in the first planar backlight 110 may have a substantially square cross-sectional shape and may have parallel opposing surfaces (eg, a top surface and a bottom surface) ). In other examples, the light directing structure can have a tapered or wedge-shaped cross-sectional shape (ie, the light directing structure can be "wedge") and have a configuration in which the first surface is substantially non-parallel to the opposing second surface.

According to various embodiments of the present invention, the edge illumination backlight used as the first planar backlight 110 further includes a capture structure feature (not shown in FIGS. 1A and 1B). The extracted structural features are used to extract light from the light directing structure and redirect the extracted light away from the light directing structure. For example, the capture feature can extract the pupil into emitted light 102 and orient the emitted light 102 away from the planar illumination surface 110' of the edge illumination backlight. The extracted structural features may include, but are not limited to, various micro-films or layers adjacent to a surface (eg, a top surface) of the light-guiding structure, and located in or adjacent to a pair of opposing surfaces. A variety of diffusers or reflectors placed on a surface.

2 is a cross-sectional view showing an example of a first planar backlight 110 in accordance with an embodiment consistent with the principles described herein. As shown in FIG. 2, the first planar backlight 110 includes a light source 112 coupled to an edge of the first planar backlight 110. The light source 112 coupled to the edge is used to generate light in the first planar backlight 110. Moreover, as shown by way of example and not limitation, the first planar backlight panel 110 includes a wedge-shaped light guiding structure 114, and the light guiding structure 114 has a pick-up junction. Feature 116. The capture structure feature 116 shown in the figures includes a micro-turn layer 116' adjacent to the planar light-emitting surface 110' (ie, the top surface), and a light-guiding structure 114 relative to the planar light-emitting surface 110'. A reflective layer 116" on the surface (i.e., the back surface). Light from the edge coupled light source 112 and guided in the light directing structure 114 will be redirected by the captured structural feature 116, in accordance with various embodiments of the present invention. And is scattered or extracted from the light guiding structure 114 to provide the emitted light 102.

In some embodiments, whether direct or edge-lit (eg, as shown in FIG. 2), the first planar backlight 110 may further have more than one additional layer or film, the layers or films These may include, but are not limited to, a brightness enhancement film (BEF), a diffuser or scattering layer, and a turning film or turning layer. For example, the diffuser can provide the emitted light 102 as scattered light. The first planar backlight panel 110 shown in Fig. 2 further includes a diffuser 118 adjacent to the planar light emitting surface 110' for providing scattered emitted light 102. According to various embodiments of the present invention (not shown in FIG. 2), other layers or films (eg, BEF, turning layers, etc.) of the first planar backlight 110 may also be disposed adjacent to the planar light emitting surface 110'. position.

Referring again to FIGS. 1A and 1B, the dual-layer backlight 100 further includes a second planar backlight 120. According to various embodiments of the present invention, the second planar backlight 120 includes a flat light guide 122 and a multi-beam diffraction grating 124. A plurality of multi-beam diffraction gratings 124 (e.g., in the form of an array) are shown by way of example in Figures 1A-B. The multi-beam diffraction grating 124 of the second planar backlight 120 couples a portion of the guided light beam 104 in the planar light guide 122 to be coupled (for example, through or by means of diffraction coupling, also referred to as "winding" Ground scattering"). In particular, the portion of the pilot beam is diffracted out to form a plurality of coupled out beams 102 that are oriented away from the first surface of the second planar backlight 120 (see section 1B). Figure). The first surface described above is a second surface relative to the second planar backlight 120. For example, the portion of the beam 104 can be coupled out of the light guide surface by the multi-beam diffraction grating 124 (ie, through the top or front surface of the planar light guide 122 as shown). Furthermore, as shown in Figures 1A-1B, in accordance with various embodiments of the present invention, the second planar back The second surface of the light panel 120 is a planar light emitting surface adjacent to the first planar backlight.

It is worth mentioning that, as shown in FIG. 1B and as described above, the coupled out beams 102 themselves are or represent beams 102 having different major angular directions. In other words, in accordance with various embodiments of the present invention, a coupled out beam 102 has a different angular orientation than the other of the coupled beams. In addition, the second planar backlight 120 may be a backlight that is substantially transparent to the light 102 emitted from the first planar backlight 110 (eg, at least in one mode of operation or state), as shown in FIG. 1A as "102" As indicated by the arrows, the arrows begin with the first planar backlight 110 and then pass through the second planar backlight 120.

According to various embodiments of the present invention, the dual layer backlight panel 100 has a switchable mode. In the first mode of the dual layer backlight panel, the first planar backlight panel 110 provides the emitted light 102 that is transmitted through the second planar backlight panel 120. In the second mode of the dual layer backlight 100, the second planar backlight 120 provides the coupled beam 102. As an example, FIG. 1A represents a first mode of the dual-layer backlight panel 100 in which the emitted light 102 provided by the first planar backlight panel 110 passes through the second planar backlight panel 120; FIG. 1B represents a double-layer backlight panel A second mode of 100 in which the emitted light 102 (e.g., beam 102) is provided by the second planar backlight 120. In some embodiments, the first and second modes may be mutually exclusive modes in time or in time. In other words, the dual layer backlight panel 100 can operate in either the first mode or the second mode at any particular point in time. In other embodiments, for example, a portion of the dual layer backlight 100 can operate in the first mode, while another portion of the dual backlight 100 can operate in the second mode.

In accordance with various embodiments of the present invention, the planar light guide 122 of the second planar backlight 120 directs light (eg, light from a source as described above) into a light beam 104. In particular, the light guide beam 104 is directed in a first direction (e.g., to the right as shown in Figure 1B). Moreover, in accordance with various embodiments of the present invention, the planar light guide 122 directs the light guide 104 at a non-zero value conduction angle. For example, the planar light guide 122 can have a dielectric material that acts as an optical waveguide. The dielectric material may have a first index of refraction that is greater than a second index of refraction of a medium surrounding the dielectric optical waveguide. Difference in refractive index through two materials For example, the guided beam 104 can be brought to full internal reflection according to more than one guiding mode of the light guide 122.

The non-zero value conduction angle is defined herein as an angle relative to a surface of the planar light guide 122 (eg, a first/top surface or a second/bottom surface). In some examples, the non-zero value conduction angle of the light guide beam 104 can be between about 10 degrees and about 50 degrees; or, in some examples, can be between about 20 degrees and about 40 degrees; or It can be between about 25 degrees and about 35 degrees. For example, the non-zero value conduction angle can be approximately 30 degrees. In other examples, the non-zero value conduction angle can be approximately 20 degrees, or approximately 25 degrees, or approximately 35 degrees.

In some examples, the light system that is directed as the pilot beam 104 is introduced at a non-zero value conduction angle (eg, about 30-35 degrees) or coupled into the planar light guide 122. In the present invention, one or more lenses (not shown), mirrors or similar reflectors (eg, inclined collimating reflectors), and a stack (not shown) may be used. A beam of light at a non-zero value conduction angle is coupled into the incident end of the planar light guide 122. When coupled into the planar light guide 122, the guided beam 104 is conducted along a direction generally away from the input end of the planar light guide 122 (as indicated by the thick arrow along an X axis in Figure 1B). In addition, the light guide beam 104 is reflected at the non-zero value conduction angle or is "bounced" between the top surface and the bottom surface of the flat light guide body 122 (for example, the light guide 104 is represented by the figure). The long, angled arrows of the light are shown).

According to some examples of the invention, the guided beam 104 produced by coupling light into the planar light guide 122 may be a collimated beam (eg, may be a collimated beam). Moreover, in accordance with certain embodiments of the present invention, the beam 104 may be a beam that is collimated in a plane that is perpendicular to the plane of the surface of the planar light guide 122. For example, the orientation of the planar light guide 122 can be positioned such that the top and bottom surfaces are parallel to the X-Y plane (eg, as shown). For example, the beam 104 can be a beam that is collimated or substantially collimated in a vertical plane (eg, the X-Z plane). In some embodiments, the beam 104 can be a beam that is collimated or substantially collimated in a horizontal direction (eg, on the X-Y plane).

In this specification, the meaning of the term "collimated" beam means that the light in the beam 104 is substantially parallel to the other rays in the beam 104 (e.g., the beam 104). Moreover, according to the definition in this specification, a beam that is offset or dispersed from the collimated beam of the guided beam 104 does not belong to a portion of the collimated beam. In accordance with various embodiments of the present invention, the light collimation process that produces the collimated beam 104 can be performed by coupling light into a lens or mirror of the planar light guide 122 (eg, a tilted collimator, etc.).

In some examples, the planar light guide 122 can be a sheet or plate shaped optical waveguide, and the optical waveguide can include an elongated and substantially planar thin plate of optically transparent dielectric material. The substantially planar thin plate-like dielectric material directs the light guide 104 through complete internal reflection. According to various embodiments of the present invention, the optically transparent material of the planar light guide 122 may comprise a variety of different dielectric materials or may be formed from a variety of different dielectric materials, wherein the dielectric materials may include, but are not limited to, More than one type of glass (for example, neodymium glass, alkaline aluminum silicate glass, borosilicate glass, etc.), and substantially optically transparent plastic or polymeric materials (eg, polymethyl methacrylate or "acrylic" Force glass", polycarbonate, etc.). In some examples, the planar light guide 122 can further include at least a portion disposed on a surface of the planar light guide 122 (eg, one of the top surface and the bottom surface or both) A coating on the top (not shown in the figure). According to some examples of the invention, the cladding layer can be used to further contribute to the complete internal reflection described above.

In accordance with various embodiments of the present invention (eg, as shown in FIGS. 1A-1B), the multi-beam diffraction grating 124 may be located on a top surface of the planar light guide 122 (eg, adjacent to the second planar backlight) The first surface of the plate 120). In other examples (not shown), the multi-beam diffraction grating can be positioned in the planar light guide 122. In still other examples (not shown), the multi-beam diffraction grating 124 may be disposed on a bottom surface of the flat light guide 122 or on a bottom surface of the flat light guide 122. In some embodiments, the second planar backlight panel 120 can include a plurality of multi-beam diffraction gratings 124 as shown in FIGS. 1A-1B. For example, the multi-beam diffraction gratings 124 may be arranged to represent or represent a multi-beam diffraction grating array. The form of the column.

In accordance with various embodiments of the present invention, multi-beam diffraction grating 124 includes a plurality of diffractive structural features 124a for diffracting light (ie, providing a diffractive effect). The diffraction effect provided is responsible for the diffraction coupling of a portion of the beam 104 out of the planar light guide 122 of the second planar backlight 120. For example, the multi-beam diffraction grating 124 may be provided with a groove on one surface of the flat light guide body 122 (see, for example, FIG. 1A, FIG. 1B, and FIG. 3A), or on the light guiding surface. One of the two diffractive structural features 124a with protruding ridges (see, for example, Figure 3B) is provided, or both may be used together. The grooves and ridges may be disposed in parallel with each other or substantially parallel to each other, and at least at some locations are perpendicular to the direction of conduction of the guided beam 104 coupled by the multi-beam diffraction grating 124.

In some examples, the diffractive structural features 124a are formed by etching, milling, or molding or applied to the surface of the planar light guide 122. As such, the material of the multi-beam diffraction grating 124 may include the material of the flat light guide 122. As shown in FIGS. 1A-1B and 3A, for example, the multi-beam diffraction grating 124 includes grooves that are formed substantially in parallel in the surface of the flat light guide 122. In FIG. 3B, as an example, the multi-beam diffraction grating 124 includes ridges that protrude from the surface of the flat light guide body and are substantially parallel to each other. In other examples (not shown), the multi-beam diffraction grating 124 can include a film or overlay attached to the surface of the planar light guide 122.

When the multi-beam diffraction grating 124 is one of a plurality of multi-beam diffraction gratings 124, the multi-beam diffraction gratings 124 can be disposed relative to the planar light guide 122 in a variety of different configurations. For example, the multi-beam diffraction gratings 124 can be disposed in a matrix across the surface of the planar light guide (eg, in an array). In another example, the multi-beam diffraction gratings 124 can be arranged in groups, and the groups can be arranged in the form of rows and columns. In another example, the multi-beam diffraction gratings 124 can be distributed substantially randomly over the surface of the planar light guide 122.

According to various embodiments of the invention, the multi-beam diffraction grating 124 may have a meander diffraction grating. According to the definition in this specification, "啁啾" is wound around The "chirped" diffraction grating exhibits or has a diffraction interval of diffractive structural features 124a that vary with a certain amplitude or length of the diffractive diffraction grating. Further, here, the diffraction interval which is changed accordingly is referred to as "啁啾". As such, the coupled beam beams exiting or exiting the multi-beam diffraction grating 124 having the 绕-type diffraction grating are emitted at different diffraction angles and become the beam 102, wherein the diffraction angles are Refers to a diffraction angle that corresponds to a different starting point across the 绕-type diffraction grating. As can be seen from the definition of 啁啾 herein, the 绕-type diffractive grating of the multi-beam diffraction grating 124 contributes to the predetermined and different major angular directions of the aforementioned beams of the beams 102.

3A is a cross-sectional view showing an example of a second planar backlight 120 having a multi-beam diffraction grating 124, in accordance with an embodiment consistent with the principles described herein. FIG. 3B is a cross-sectional view showing a portion of a second planar backlight 120 having a multi-beam diffraction grating 124 in accordance with an embodiment consistent with the principles described herein. Figure 3C is a perspective view showing a portion of a second planar backlight having a multi-beam diffraction grating 124 in Figure 3A or Figure 3B, in accordance with an embodiment consistent with the principles described herein. As an example and not limitation of the present invention, the multi-beam diffraction grating 124 shown in FIG. 3A includes grooves in the surface of the flat light guide 122. For example, the multi-beam diffraction grating 124 shown in FIG. 3A may represent one of the grooved multi-beam diffraction gratings 124 shown in FIGS. 1A-1B. The multi-beam diffraction grating 124 shown in Fig. 3B may include a ridge protruding from the surface of the flat light guide.

In FIGS. 3A-3B (also shown by way of example and not limitation to FIGS. 1A-1B), the multi-beam diffraction grating 124 is a 绕-type diffraction grating. In particular, as shown, the diffractive structural features 124a are closer to each other at the first end 124' of the multi-beam diffraction grating 124 than at the second end 124". In addition, the diffraction shown in the figures The diffraction interval d of the structural feature 124a varies from the first end 124' to the second end 124" with distance. In some examples, the 绕-type diffraction grating of the multi-beam diffraction grating 124 may have or may exhibit a mean diffraction interval d that varies linearly with distance. As such, the 绕-type diffraction grating can be referred to as a "linear 啁啾" diffraction grating.

In another example (not shown), the 绕-type diffraction grating of the multi-beam diffraction grating 124 may exhibit a nonlinear 啁啾 of the diffraction interval d . The various nonlinearities used to implement the 绕-type diffraction grating may include, but are not limited to, an index 啁啾, a logarithm 啁啾, or a modified 啁啾, a substantially uneven, or a random but monotonous distribution. . Non-monotonic crucibles may also be used in the present invention, including but not limited to, sinusoidal, triangular or serrated. Combinations of any of the above types of crucibles can also be used in the multi-beam diffraction grating 124 in the present invention.

As shown in FIG. 3C, the multi-beam diffraction grating 124 may be on the meandering and curved surface of the flat light guide 122 (ie, the multi-beam diffraction grating 124 is a curved 绕-type diffraction grating). A diffractive structural feature 124a (eg, a groove or ridge) is disposed in the middle. As shown by the thick arrows in FIGS. 3A-3B, the light guide 104 has an incident direction with respect to the multi-beam diffraction grating 124 and the flat light guide 12. Also shown in the figure is a plurality of coupled or emitted beams 102 directed away from the multi-beam diffraction grating 124 at the surface of the planar light guide 122. The light beam 102 shown in the figure is directed toward a plurality of different predetermined principal angular directions. More specifically, as shown, the elevation angles and azimuths of the different predetermined principal angular directions of the emitted light beams 102 are different (e.g., thereby forming a light field). In accordance with various examples of the present invention, the predefined chirp of the diffractive structural feature 124a and the curvature of the diffractive structural feature 124a contribute to different predetermined principal angular directions of the emitted beam 102.

}的方位分量

，可以由繞射結構特徵124a在光束102的起點(即，入射的導光束104被耦合出的點)的方位角

所決定。如此一來，至少以其各自的方位分量

而言，在多光束繞射格柵124中的繞射結構特徵124a的改變方位會產生具有不同主角度方向{θ,

}之不同的光束102。 For example, due to the curved relationship, the diffractive structural features 124a in the multi-beam diffraction grating 124 may have different orientations relative to the direction of incidence of the guided beam 104. In particular, the orientation of the diffractive structural feature 124a at a first point or orientation in the multi-beam diffraction grating 124 is not the same as the orientation of the diffractive structural feature 124 at other points or locations. According to some examples of the invention, the main angular direction of the beam 102 is { θ, relative to the coupled or emitted beam 102 .

Azimuth component of }

Azimuth of the diffraction structure feature 124a at the beginning of the beam 102 (i.e., the point at which the incident beam 104 is coupled out)

Determined. In this way, at least with their respective azimuthal components

In this case, the changing orientation of the diffractive structural features 124a in the multi-beam diffraction grating 124 will have different main angular directions { θ,

Different beam 102 of }.

。在本說明書中，「底層繞射格柵」意指疊加設置的多個非彎曲繞射格柵中的繞射格柵，產生了多光束繞射格柵124的繞射結構特徵124a。因此，在沿著繞射結構特徵124a之曲線上的一定點處，該曲線會具有與沿著該等繞射結構特徵124a之曲線上的另一點大致不同的特定方位角

。此外，該特定方位角

會造成從該點發出的光束102的主角度方向{θ,

}之對應的方位分量

。在某些實例中，繞射結構特徵124a(例如，凹槽、脊部等)的曲線係代表了一圓形的區段。該圓形可以與導光體表面共面。在其他的實例中，舉例來說，曲線亦可以代表與導光體表面共面的一橢圓形或者其他彎曲形狀的一區段。 In particular, at different points along the curve along the diffraction structure feature 124a, the bottom diffraction grating system associated with the curved diffraction structure feature 124a in the multi-beam diffraction grating 124 has a different azimuth

. In the present specification, "underlying diffraction grating" means a diffraction grating in a plurality of non-bent diffraction gratings arranged in a superimposed manner, and a diffraction structure feature 124a of the multi-beam diffraction grating 124 is produced. Thus, at a certain point along the curve along the diffractive structural feature 124a, the curve will have a particular azimuth that is substantially different from another point on the curve along the diffractive structural feature 124a.

. In addition, the specific azimuth

Will cause the main angular direction of the beam 102 from this point { θ,

Azimuth component of }

. In some examples, the curve of the diffractive structural feature 124a (eg, groove, ridge, etc.) represents a circular segment. The circle can be coplanar with the surface of the light guide. In other examples, for example, the curve may also represent a section of an elliptical or other curved shape that is coplanar with the surface of the light guide.

In other examples, multi-beam diffraction grating 124 may have a "fragment" curved diffractive structural feature 124a. In particular, although the diffractive structural features 124a themselves are not necessarily substantially smooth or continuous, the diffractive structural features 124a may still have different points along the diffractive structural features 124a in the multi-beam diffraction grating 124. The orientation of the different angles with respect to the direction of incidence of the guided beam 104. For example, the diffractive structural feature 124a can be a groove that includes a plurality of substantially straight segments, and wherein each segment has an orientation that is different from the adjacent segments. In summary, according to various examples of the invention, the different angles of the segments may approximate a curve (eg, a segment of a circle). However, in other examples of the invention, the diffractive structural features 124a may only have different orientations at different locations in the multi-beam diffraction grating 124 relative to the direction of incidence of the guided beam, but it is not Will approximate a specific curve (for example, a circle or an ellipse).

Referring again to FIGS. 1A-1B, the second planar backlight 120 of the dual layer backlight 100 further includes a light source 126, in accordance with some embodiments of the present invention. For example, the light source 126 can be coupled to the input end of the flat light guide 122 of the second planar backlight 120. In various embodiments, light source 126 can include substantially any kind of light source, and the type of light source can include, but is not limited to, a light emitting diode (LED) and a laser. In some embodiments, light source 126 can produce substantially monochromatic light having a narrower spectrum and represented by a particular color. In particular, the special The fixed color can be or can represent a primary color (eg, the primary color of the electronic display). For example, light source 126 can generate a plurality of different colors of light representing a plurality of primary colors. For example, the main colors may include red light, green light, and blue light. In addition, the primary color may be a primary color selected according to a color model, which may include, but is not limited to, Red-Green-Blue for supporting the color gamut of the color electronic display. , RGB) color model. Still further, a dual layer backlight 100 having a light source 126 can be disposed in an electronic display to provide light, for example, to provide a primary color of light.

In some embodiments, light source 126 can have multiple light emitters 126a. The light emitters 126a (or, in a broad sense, the light source 126) are used to provide light to the planar light guide 122 as the light guide 104, i.e., as the light guide 104. Depending on the embodiment of the light provided that includes different colors of light (e.g., different primary colors), when the provided light is coupled into the planar light guide 122, it is directed into a plurality of differently colored beams 104. . For example, the light emitters 126a can be used to generate light of the different primary colors. In some embodiments, light emitters 126a of different colors in the light emitters can be disposed at the input end of the planar light guide 122 in a manner that is laterally offset from one another (not separately shown).

In accordance with certain embodiments of the present invention, different colored light guides 104 will be directed in the planar light guide 122 at different and color-specific non-zero value conduction angles. For example, the red pilot beam 104 coupled into the planar light guide 122 will conduct at a first non-zero value conduction angle in the planar light guide 122; the green guide coupled into the planar light guide 122 The beam 104 will conduct at a second non-zero value conduction angle in the planar light guide 122; and the blue guided beam 104 coupled into the planar light guide 122 will be in the third non-stable light in the planar light guide 122 Zero-value conduction angle conduction. Moreover, in accordance with certain embodiments of the present invention, the first, second, and third non-zero value conduction angles are respectively different angles.

According to some embodiments, light source 126 may be a colored light source that includes a plurality of LEDs. For example, the LEDs can represent different colors in the primary colors of the color electronic display. In particular, for example, the LEDs may include a red LED for generating red light in an RGB color model, a green color for generating green light LEDs, as well as blue LEDs for producing blue light. In some embodiments, light source 126 includes a linear array of light emitters 126a disposed along the edges of planar light guides 122. For example, each of the light emitters 126a can include a red LED, a green LED, and a blue LED. Light source 126 can be used to generate collimated light (eg, using a collimating reflector or lens). For example, the parabolic reflector 126b shown in FIGS. 1A and 1B can generate a collimated beam 104 as the coupling light enters the planar light guide 122 from the light emitter 126a. According to various embodiments of the present invention, any collimator (eg, a collimating lens, a collimating reflector, etc.) may be passed between the light source 126 and the planar light guide 122 to provide guidance in the planar light guide 122. Collimate the beam.

According to some embodiments of the present invention, the dual layer backlight panel 100 further includes a light blocking layer 130 disposed between the first planar backlight panel 110 and the second planar backlight panel 120. According to some embodiments of the present invention, the light blocking layer 130 selectively blocks light emitted from the second surface (eg, the back surface) of the second planar backlight 120 into the first planar backlight 110. In particular, the light blocking layer 130 blocks light emitted from the second planar backlight 120 toward the first planar backlight 110, that is, light emitted in the "first direction". On the other hand, in at least some modes of operation of the dual-layer backlight 100 and according to at least some embodiments of the dual-layer backlight 100, the light-blocking layer 130 further illuminates the light emitted by the first planar backlight 110 to the second The direction of the second surface of the planar backlight 120 is transmitted, that is, to the "second direction" opposite to the first direction. As such, in accordance with certain embodiments of the present invention, the light blocking layer 130 can represent a unidirectional light blocking layer 130. In other embodiments, the light blocking layer 130 can selectively block light from passing through the light blocking layer 130 and block light from the first planar backlight 110 from reaching the second planar backlight 120. In these embodiments, for example, the light blocking layer 130 may block light only in a particular mode of the dual layer backlight 100. In FIG. 1B, the light blocking layer 130 for blocking light is displayed in a diagonal manner, and the light blocking layer 130 for transmitting light is represented in an unmarked oblique line in FIG. 1 (for example, from the first planar backlight) Light 102 emitted by the board 110).

4A is a cross-sectional view showing a portion of an exemplary dual layer backlight panel 100 in accordance with an embodiment consistent with the principles described herein. Figure 4B is A cross-sectional view of a portion of another exemplary dual layer backlight panel 100 is shown in accordance with an embodiment consistent with the principles described herein. For example, the portions shown in FIGS. 4A and 4B may be a portion of the double-layered backlight panel 100 shown in FIG. 1B. In particular, the dual-layer backlight panel 100 shown in FIGS. 4A-4B includes a first planar backlight panel 110, a second planar backlight panel 120, and a first planar backlight panel 110 and a second planar backlight panel 120. Light blocking layer 130. As shown in FIGS. 4A to 4B, the light blocking layer 130 is used to block light.

In some embodiments, for example, as shown in FIG. 4A, the light blocking layer 130 may block light generated from the second planar backlight 120 and conducted substantially in the negative Z-axis direction. For example, the diffracted beam 104 produced by the diffraction of the multi-beam diffraction grating 124 can be simultaneously coupled out of the beam 102 (eg, a beam that is oriented substantially toward the positive Z-axis) and scattered or substantially negative to the Z-axis. A second beam 102a oriented in the direction. As shown in FIG. 4A, the light blocking layer 130 can be used to block the second light beam 102a.

Alternatively or in addition (eg, as shown in FIG. 4B), the light blocking layer 130 may block light 102b that is conducted from the first planar backlight 110 toward the second planar backlight 120 toward the second planar backlight 120. In particular, the light blocking layer 130 may be in a mode in which the second planar backlight 120 is activated or in a mode in which the second planar backlight 120 provides a coupled beam 102 (ie, as shown), blocking transmission in the positive Z-axis direction. Light 102. For example, light 102b that is blocked by the light blocking layer 130 and oriented in the positive Z-axis direction may represent light generated by the first planar backlight 110 or represent light from the first planar backlight 110. In another example, light 102b oriented in the positive Z-axis direction can represent light that is backscattered or reflected from the second planar backlight panel 120 and that is backscattered or reflected by the first planar backlight panel 110 toward the second planar backlight panel.

According to some embodiments of the invention, the light blocking layer 130 may provide passive light blocking or active light blocking of light conducted in a first direction (eg, via switching). For example, the light blocking layer 130 may be a substantially passive layer that blocks light conducted in the first direction and simultaneously transmits light that is conducted in the second direction. As such, the light blocking layer can remain substantially unchanged in the first mode of operation and the second mode of operation of the dual layer backlight panel 100. Examples of passive layers that may be used as the light blocking layer 130 include, but are not limited to, unidirectional perfect absorbers, polarizers or polarization layers, and angle filters. For example Other examples of passive layers include multi-band filters (eg, multi-band color filters) that can selectively block (eg, reflect, absorb, etc.) the particular wavelengths produced by the second planar backlight 120. Light, and at the same time, allows light of different wavelengths produced by the first planar backlight 110 to pass.

In another example, the light blocking layer 130 can be an active layer for blocking transmission of light in a light blocking mode or state and transmitting light in an optical transmission mode or state. When the second planar backlight 120 is activated, the active light blocking layer 130 can be selectively switched into the light blocking state, thereby preventing light from being transmitted from the second planar backlight 120 to the first planar backlight 110. And preventing light from entering the first planar backlight 110. The second planar backlight panel 120 is activated in the second mode of the dual layer backlight panel 100, as described above. In addition, when the first planar backlight 110 is activated, the active light blocking layer 130 can be selectively switched into the light transmitting state, thereby allowing light to pass through the second planar backlight 120 and conduct away from the second planar backlight 120. Becomes the emitted light 102. The first planar backlight 110 is activated in a first mode of the dual layer backlight 100, as described above. Examples of active light blocking layer 130 include, but are not limited to, a light valve (eg, a liquid crystal light valve) or a similar switchable absorbing layer. Other examples include various "active" baffle configurations based on electromechanical structures (eg, microelectromechanical mirrors), electroabsorption (eg, semiconductor-based structures), and various nonlinear crystals as well as organic polymers.

In accordance with certain embodiments consistent with the principles described in this specification, the present invention provides a two-dimensional/three-dimensional mode switching electronic display. The two-dimensional/three-dimensional mode switching electronic display can emit modulated light corresponding to or representing a two-dimensional pixel of the two-dimensional/three-dimensional electronic display in the first mode. In addition, the two-dimensional/three-dimensional mode switching electronic display can emit modulated and differently coupled light beams that act as or represent two-dimensional/three-dimensional mode switching electronic displays corresponding to different three-dimensional shapes in the second mode. The voxel of the perspective. As an example, the first mode described above may be referred to as a two-dimensional mode, and the second mode may be referred to as a three-dimensional mode. In the two-dimensional mode, the two-dimensional/three-dimensional mode switching electronic display is used to display two-dimensional information (for example, two-dimensional images, text, etc.). On the other hand, in the three-dimensional mode, the two-dimensional/three-dimensional display is used to display three-dimensional information (for example, three-dimensional images). Especially two-dimensional The three-dimensional mode switching electronic display can represent a holographic or naked-eye three-dimensional electronic display in a second mode or a three-dimensional mode. In other words, in accordance with various examples of the present invention, different beams of modulated and differently directed beams may correspond to different "views of view" associated with a three-dimensional information display. For example, different viewing angles can be used to switch the electronic display through the 2D/3D mode in the second mode or the 3D mode to provide an information representation of "naked eyes" (eg, naked eye 3D stereoscopic display, holographic, etc.).

Figure 5 is a block diagram showing an example of a two-dimensional/three-dimensional mode switching electronic display in accordance with an embodiment consistent with the principles of the present invention. The 2D/3D mode switching electronic display 200 can be used to display two-dimensional information or three-dimensional information, which may include, but is not limited to, two-dimensional images, text, and three-dimensional images. In particular, the two-dimensional/three-dimensional mode switching electronic display 200 shown in FIG. 5 emits modulated light 202 representing a two-dimensional pixel. As an example, the two-dimensional/three-dimensional mode switching electronic display 200 can emit modulated light 202 representing a two-dimensional pixel in a two-dimensional mode of operation. In addition, the two-dimensional/three-dimensional mode switching electronic display 200 shown in FIG. 5 emits modulated light beams 202' having different main angular directions, and the modulated light beams 202' represent switching electrons corresponding to two-dimensional/three-dimensional modes. The three-dimensional pixels of the display 200 are of different viewing angles in a three-dimensional mode of operation.

In some embodiments, modulated light 202 and modulated light beam 202' may further represent different colors, and the two-dimensional/three-dimensional mode switched electronic display may be a color display. It should be noted here that the modulated light 202 and the modulated light beam 202' shown in FIG. 5 are emitted to different regions of the electronic display 200. For ease of explanation, the regions are respectively labeled as "two-dimensional mode" and "3D mode". This indication is for the purpose of illustrating that the two-dimensional mode and the three-dimensional mode can be selectively activated in the electronic display 200, thereby providing two-dimensional information and three-dimensional information. It should be understood that the two-dimensional/three-dimensional mode switching electronic display 200 can selectively operate only in the first mode or the second mode, in accordance with certain embodiments of the present invention.

The two-dimensional/three-dimensional mode switching electronic display 200 includes a planar backlight 210 having a planar light emitting surface for emitting light 204. The emitted light 204 is the source of the modulated light 202 emitted by the two-dimensional/three-dimensional mode switching electronic display 200 in the first mode. According to some embodiments of the invention, flat The face backlight 210 may be substantially similar to the first planar backlight 110 described above for the dual layer backlight 100. In particular, in some embodiments, the light 204 emitted by the planar backlight 210 can be scattered or substantially scattered light. For example, the planar backlight panel 210 can include a scattering layer or diffuser adjacent to a planar light emitting surface, wherein the diffuser is used to scatter the emitted light (ie, to produce substantially scattered light). In other embodiments, according to some embodiments, the emitted light 204 can be substantially unidirectional light. In some embodiments, the emitted light 204 can be white light, while in other embodiments, the emitted light 204 can be light having a particular color or a particular plurality of colors (eg, one of red, green, and blue) Color or multiple colors). According to various embodiments, the emitted light 204 may be provided by a light source of the planar backlight 210. Moreover, in some embodiments, the planar backlight 210 can include a wedge-shaped light guide having a light extraction layer for extracting light from the wedge-shaped light guide and The extracted light is redirected through the diffuser to become emitted light 204.

The two-dimensional/three-dimensional mode switching electronic display 200 shown in FIG. 5 further includes a light guide 220 for guiding the light beam. The light guide beam in the light guide body 220 is the source of the modulated light beam 202' that is emitted in the second mode by the two-dimensional/three-dimensional mode switching electronic display 200. According to some embodiments of the present invention, the light guide 220 may be a flat light guide and may be substantially similar to the flat light guide 122 described above for the dual layer backlight 100. For example, light directing body 220 can be a sheet-like optical waveguide having a planar thin plate dielectric material and directing light in a manner that is totally internal reflective. In some embodiments, the light guide 220 as a planar light guide can be disposed in a manner substantially coplanar with the planar backlight 210 (eg, as shown in FIGS. 1A and 1B). Further, for example, the second surface (eg, the rear surface) of the light guide body 220 may be adjacent to the planar light emitting surface of the planar backlight panel 210. The first surface (top surface) of the light guide 220 relative to the second surface is a light emitting surface that produces a modulated beam 202' (e.g., coupled out of the beam 204' as described below).

In accordance with various embodiments of the present invention, light guide 220 directs the light beam at a non-zero value conduction angle in light guide 220. In some embodiments, the light guide can include a plurality of different colored light guides. Moreover, in accordance with certain embodiments of the present invention, The light guide in the light guide 220 can be a collimated beam (ie, the light can be directed as a collimated or substantially collimated beam). As such, the light guide body 220 can guide the collimated light beam at a non-zero value conduction angle in the light guide body 220.

The two-dimensional/three-dimensional mode switching electronic display 200 shown in FIG. 5 further includes an array of multi-beam diffraction gratings 230. According to various embodiments of the present invention, the array of multi-beam diffraction gratings 230 may be located in the surface of the light guide body 220, on the surface of the light guide body 220, or on the surface of the light guide body 220. As an example, an array of multi-beam diffraction gratings 230 may be located on a first surface or front surface of light guide 220. According to various embodiments of the present invention, the array of multi-beam diffraction gratings 230 couples a portion of the guided light beam into a plurality of coupled outgoing light beams 204' having different major angular directions, and the coupled outgoing light beams 204' The different three-dimensional viewing angles of the electronic display 200 are switched on behalf of or corresponding to the two-dimensional/three-dimensional mode.

In addition, the array of multi-beam diffraction gratings 230 couples the coupled beam 204' through the first surface of the light guide 220 and directs the coupled beam 204' away from the first surface, for example toward Different main angular orientations are oriented. In some embodiments, the array of multi-beam diffraction gratings 230 can be substantially similar to the multi-beam diffraction grating 124 of the dual layer backlight 100 described above.

As an example, the array of multi-beam diffraction gratings 230 can include a meander diffraction grating. In some embodiments, the diffractive structural features (eg, grooves, ridges, etc.) of the multi-beam diffraction grating 230 are diffractive structural features having curvature. The curved diffractive structural features may include curved ridges or grooves (in other words, continuous curved or segmentally curved structural features), and have a curvature that varies with distance from the array of multi-beam diffraction gratings 230. The spacing between the features of the diffraction structure.

As shown in FIG. 5, the two-dimensional/three-dimensional mode switching electronic display 200 further includes a light valve array 240. In accordance with various examples of the present invention, light valve array 240 includes a plurality of light valves for modulating one of the emitted light 204 and the coupled outgoing light beams 204' or both. More specifically, the light valve in the light valve array 240 can modulate the emitted light 204 to provide for switching the electronic display 200 into or representing a two-dimensional/three-dimensional mode (eg, in a first mode or a two-dimensional mode) The modulated light 202 of the two-dimensional pixel. Similarly, in the light valve array 240 The light valve can modulate the coupled out beams 204', thereby providing a modulated beam 202 of a voxel that is or represents a two-dimensional/three-dimensional mode switching electronic display 200 (eg, in a second mode or a three-dimensional mode) '. Moreover, the different beam profiles in the modulated beam 202' represent different three-dimensional viewing angles of the two-dimensional/three-dimensional mode switching electronic display 200. In various examples, different types of light valves can be used in the light valve array 240, including but not limited to, more than one liquid crystal light valve, an electrophoretic light valve, and an electrowetting light valve. The dashed lines used in Figure 5 emphasize the modulation of light 202 and beam 202' by way of example.

In accordance with some embodiments of the present invention, light directing body 220 is a location between the planar light emitting surface of planar backlight 210 and light valve array 240. In some embodiments, the array of multi-beam diffraction gratings 230 is located between the light guide 220 and the light valve array 240 and may be adjacent to the first surface of the light guide 220. Furthermore, the light guide 220 and the array of multi-beam diffraction gratings 230 are used to transmit the light 204 emitted by the planar backlight 210, for example, to transmit the light 204 from the second surface of the light guide 220 to the first surface. . In other words, in accordance with certain embodiments of the present invention, the array of light guides 220 and multi-beam diffraction gratings 230 may be substantially transparent to the emitted light 204 of the planar backlight 210.

Moreover, as shown in FIG. 5, the two-dimensional/three-dimensional mode switching electronic display 200 can include a light source 250, in accordance with some embodiments of the present invention. The light source 250 is optically coupled to the input end of the light guide body 220. In some embodiments, light source 250 is substantially similar to light source 126 described above for dual layer backlight 100. In particular, light source 250 can include a plurality of light emitters (eg, LEDs). For example, in some embodiments, light source 250 can include a plurality of light emitters disposed along an input end of light guide 220, thereby providing a corresponding plurality of light guides in light guide 220. The beams may be directed from the input end of the light guide 220 across the light guide 220 to an end of the light guide 220 relative to the input end in a substantially parallel band at an individual non-zero value conduction angle. The guided beam in conduction interacts with an array of multi-beam diffraction gratings 230 adjacent to the first surface of the light guide 220. As an example, the light emitters of light source 250 are arranged in a linear array, and each light emitter produces a different collimated beam of light in light guide 220.

According to some embodiments of the invention, light source 250 produces light of different colors (ie, a colored light source). As such, in some embodiments, the two-dimensional/three-dimensional mode switching electronic display can be a color electronic display. For example, the light emitters can include a first light emitter for emitting light of a first color (eg, red light), a second light for emitting light of a second color (eg, green light) a transmitter, and a third light emitter for emitting light of a third color (eg, blue light). As an example, the first light emitter can be a red light emitting diode (LED), the second light emitter can be a green LED, and the third light emitter can be a blue LED. In other examples, as an example, a light emitter can include each of a red LED, a green LED, and a blue LED, and thus becomes a colored light emitter.

In some embodiments where light source 250 is a colored light source, beams of different colors may be directed in light guide 220 at different and color-specific non-zero value conduction angles. In addition, the color-specific conduction angle can produce a colored coupled out beam 204' from the multi-beam diffraction grating 230, wherein the multi-beam diffraction grating 230 forms a color-specific light field, and the color-specific light field provides The color pixels of the different three-dimensional viewing angles of the electronic display 200 are switched corresponding to the two-dimensional/three-dimensional mode. In accordance with various embodiments of the present invention, the color-specific light fields may have cone angles that are substantially similar to one another, and thus produce color-specific pixels that are substantially similar to each other in three-dimensional views other than color.

In accordance with some embodiments of the present invention (not shown in FIG. 5), the two-dimensional/three-dimensional mode switching electronic display 200 further includes a light blocking layer disposed between the planar backlight 210 and the light guide 220. In some embodiments, the light blocking layer can be substantially similar to the light blocking layer 130 described above for the dual layer backlight 100. In other words, the light blocking layer can pass light emitted from the planar backlight 210 and block (eg, absorb or reflect) any light emitted by the light guide 220 toward the planar backlight 210. In addition, the light blocking layer can be an active or passive light guiding layer, as described above for the light guiding layer 130. In particular, in accordance with certain embodiments of the present invention, the light blocking layer can include a selective switching absorber layer between the planar backlight 210 and the light guide 220.

The switching absorption layer can pass the light 204 emitted by the planar backlight 210 in the first mode or the two-dimensional mode of the two-dimensional/three-dimensional mode switching electronic display 200, thereby allowing the emitted light 204 to pass through the light guiding body 220 and the multi-beam winding. The shot grid 230 then reaches the light valve array 240 and is modulated by the light valve array 240 to become modulated modulated light 202. Moreover, the switching absorbing layer can be used to absorb any light emitted from the second surface of the light guide 220 in the second or three dimensional mode of the two-dimensional/three-dimensional mode switching electronic display 200. According to some embodiments of the present invention, the absorption of light emitted by the second surface in the second mode may prevent light leakage from the light guide 220 from interfering with the coupled out beam 204' produced by the first surface of the light guide 220.

In accordance with certain examples consistent with the principles described herein, the present invention provides a method of providing backlighting for a two-dimensional/three-dimensional electronic display having a two-dimensional/three-dimensional switching mode. Figure 6 is a flow diagram of a method of providing backlighting for a two-dimensional/three-dimensional electronic display having a two-dimensional/three-dimensional switching mode, in accordance with an embodiment consistent with the principles described herein.

As shown in FIG. 6, a method 300 for providing backlighting for a two-dimensional/three-dimensional electronic display includes the step 310 of emitting light from a light emitting surface of a first planar backlight in a first switching mode. In some embodiments, the first planar backlight panel is similar to the first planar backlight panel 110 described above for the dual layer backlight panel 100. Moreover, in accordance with some embodiments of the present invention, the first switching mode and the light system emitted in step 310 are substantially similar to the first mode (eg, two-dimensional mode) and emitted light described above for dual-layer backlight 100. 102.

The method 300 for providing backlighting for a two-dimensional/three-dimensional electronic display further includes a step 320 of: in the second switching mode, using a multi-beam diffraction grating to diffract the planar light guide body coupled to the second planar backlight Part of the beam. In accordance with various embodiments of the present invention, the step 320 of diffractive coupling provides a plurality of coupled out-beams oriented in a plurality of major angular directions away from the second planar backlight, wherein the major angular directions correspond to two-dimensional / 3D viewing angles of 3D electronic displays. In some embodiments, the second planar backlight panel is substantially similar to the second planar backlight panel 120 of the dual layer backlight panel 100 described above. In particular, the flat light guide, the guided beam and the multi-beam diffraction grating may each be substantially similar to the above-mentioned double-layered back The flat light guide 122, the light guide beam and the multi-beam diffraction grating 124 of the light plate 100. As such, in accordance with certain embodiments of the present invention, the second switching mode may be substantially similar to the second mode of the dual layer backlight 100 (eg, three dimensional mode).

As an example, a method 300 of providing backlighting for a two-dimensional/three-dimensional electronic display may further include the step of directing a light guide beam in a planar light guide of the second planar backlight. Further, for example, the beam can be directed as a collimated beam at a non-zero value conduction angle. In some embodiments, the light guide beam can comprise a plurality of light beams of different colors, wherein the light beams of different colors are guided in the planar light guide body with corresponding different and color-specific non-zero value conduction angles. Moreover, in accordance with various embodiments of the present invention, the second planar backlight transmits the emitted light from the first planar backlight through the second planar backlight and re-emits the emitted light in the first switching mode.

According to various embodiments of the invention, the multi-beam diffraction grating is located on the surface of the planar light guide, in the surface of the planar light guide or on the surface of the planar light guide. As an example, the multi-beam diffraction grating may be formed in the planar light guide in the form of a groove, a ridge, or the like. In other examples, the multi-beam diffraction grating can include a film on the surface of the light guide. In other examples, the multi-beam diffraction grating can be disposed at other locations, which can include, but are not limited to, in a planar light guide. According to some embodiments of the invention, the multi-beam diffraction grating system includes a 绕-type diffraction grating having one of a curved groove and a curved ridge spaced apart from each other. In some embodiments, the multi-beam diffraction grating can be a linear 绕-type diffraction grating.

In accordance with various embodiments of the present invention, the step 320 of diffracting a portion of the light guide beam produces a plurality of emitted light beams directed toward a surface remote from the planar light guide (eg, a surface having a multi-beam diffraction grating) ( Or couple out the beam). Each of the plurality of beams is oriented in a different predetermined major angular direction away from the surface. In particular, as a result of the diffraction coupling performed by the multi-beam diffraction grating at step 320, one of the beams of the beams will have a different major angular orientation than the other of the beams. The different main angular directions of the emitted light beams correspond to different three-dimensional viewing angles of the three-dimensional electronic display. As such, the two-dimensional/three-dimensional electronic display can selectively provide one in the second switching mode. 3D electronic display. On the other hand, for example, when the emitted light from the first planar backlight in step 310 is transmitted through the second planar backlight in the first switching mode of the two-dimensional/three-dimensional electronic display, the two-dimensional/three-dimensional electronic display may Selectively provide a two-dimensional electronic display.

In some embodiments, the method 300 of providing a backlight for a two-dimensional/three-dimensional electronic display further includes the step 330 of using the plurality of light valves to perform the emitted light in the first switching mode and the coupled out beam in the second switching mode. Modulation. In particular, the selectively emitted light from the first planar backlight and the plurality of coupled out beams selectively generated from the second planar backlight are respectively passed in the first switching mode or the second switching mode in step 330. It is modulated by a light valve or by interacting with a light valve. In the modulated light in step 330, a two-dimensional pixel of the two-dimensional/three-dimensional electronic display is formed in the first switching mode, and a three-dimensional pixel of the two-dimensional/three-dimensional electronic display is formed in the second switching mode. For example, the modulated out-coupled beam in step 330 can provide multiple three-dimensional views of a two-dimensional/three-dimensional electronic display (eg, a naked-eye three-dimensional electronic display).

In some examples, the light valves used to modulate in step 320 are substantially similar to the light valves in the light valve array 240 described above for the two-dimensional/three-dimensional mode switching electronic display 200. For example, the light valve can include a liquid crystal light valve. In other examples, the light valve can be another type of light valve, which can include, but is not limited to, an electrowetting light valve and an electrophoretic light valve. In accordance with certain embodiments of the present invention (e.g., in the case of employing a color light emitter, utilizing a color filter, etc.), the modulation of light in step 330 can be applied to a color specific condition.

According to some embodiments of the present invention, a method of providing a backlight for a two-dimensional/three-dimensional electronic display further includes selectively blocking light emitted from a second planar backlight to a direction of the first planar backlight in the second switching mode step. According to some embodiments of the present invention, the light blocking layer employed in the step of selectively blocking light may be substantially similar to the light blocking layer 130 described above for the dual layer backlight 100. As an example, the step of selectively blocking light in certain embodiments may include selectively absorbing light using a switchable or actively light absorbing layer. In some embodiments, the method 300 of providing backlighting for a two-dimensional/three-dimensional electronic display can further include The switching mode operates the first portion of the two-dimensional/three-dimensional electronic display and operates the other portion of the two-dimensional/three-dimensional electronic display in the second switching mode.

Accordingly, the present invention provides an example of a dual layer backlight panel, a two-dimensional/three-dimensional mode switching electronic display, and a backlight for a two-dimensional/three-dimensional electronic display having a two-dimensional/three-dimensional switching mode. Those skilled in the art should understand that the examples described above are merely illustrative examples of numerous examples and embodiments that are representative of the principles of the invention. It will be apparent to those skilled in the art that various other configurations can be made without departing from the scope of the invention as defined by the scope of the invention.

100‧‧‧Double-sided backlight

102‧‧‧Light/emitted light/beam/coupled out beam

110‧‧‧First flat backlight

110'‧‧‧ flat light surface

120‧‧‧Second flat backlight

122‧‧‧Slab light guide

124‧‧‧Multi-beam diffraction grating

126‧‧‧Light source

130‧‧‧Light barrier

Claims (26)

A dual-layer backlight board comprising: a first planar backlight having a planar light-emitting surface for emitting light; and a second planar backlight having a flat light guide and a multi-beam diffraction grating, the multi-beam The diffraction grating couples a portion of a light guide beam in the planar light guide body into a plurality of coupled light beams, and the coupled light beams are directed away from a first surface of the second planar backlight Orienting, the first surface is opposite to a second surface of the second planar backlight, and the second surface is adjacent to the planar light emitting surface of the first planar backlight; wherein the light is coupled out of the light beam A beam of light has a major angular direction that is different from the other of the coupled beams. The double-layer backlight panel of claim 1, wherein the first planar backlight panel provides emitted light transmitted through the second planar backlight panel in a first mode, the second planar backlight panel being A second mode provides the coupled out beams. The double-layer backlight according to claim 1, wherein the flat light guiding system of the second planar backlight guides the light guiding beam at a non-zero value conduction angle, and the multi-beam diffraction grating system And a surface of the flat light guide adjacent to the first surface of the second planar backlight. The double-layer backlight panel of claim 1, wherein the light guide beam is a collimated light beam guided in the flat light guide body. The double-layer backlight panel of claim 1, wherein the multi-beam diffraction grating is a linear 绕-type diffraction grating. The double-layer backlight panel of claim 1, wherein the coupled light beams having different main angular directions form a light field, and the light field represents three-dimensional images corresponding to different viewing angles of a three-dimensional electronic display. Pixel. The double-layer backlight of claim 1, further comprising a light source coupled to an input end of the second planar backlight, the light source providing a plurality of different colors of light, The light systems of different colors are directed into a plurality of light beams of different colors, wherein the different color light beams of the different color light guides are in the flat light guide body with different, color-specific non-zero value conduction angles. guide. The double-layer backlight board of claim 1, further comprising a light blocking layer between the first planar backlight and the second planar backlight, wherein the function of the light blocking layer is: selecting Resisting light emitted by the second planar backlight to the first planar backlight, and/or selectively blocking light from passing through the first planar backlight to the second of the second planar backlight surface. An electronic display comprising the dual-layer backlight of claim 1, wherein the electronic display further comprises a light valve that is positioned adjacent to the first surface of the second planar backlight Position and for modulating light from the dual layer backlight, the modulated light system corresponding to pixels of the electronic display. The electronic display of claim 9, wherein the light valve comprises a plurality of liquid crystal light valves. A two-dimensional/three-dimensional mode switching electronic display, comprising: a flat backlight board having a planar light emitting surface for emitting light; a light guiding body adjacent to the planar light emitting surface of the planar backlight board, the light guiding system guiding a light beam; a multi-beam diffraction grating array disposed on a surface of the light guiding body, the multi-beam winding A multi-beam diffraction grating in the array of grating grids couples a portion of the guiding beam into a plurality of coupled beams having different main angular directions, and the coupled beam beams represent the two-dimensional/three-dimensional mode switching a different three-dimensional view of the electronic display; and a light valve array that selectively modulates the emitted light into a first mode of two-dimensional pixels and modulates the coupled light beams to correspond to the two-dimensional/three-dimensional The mode switches the voxels of different three-dimensional views in a second mode of the electronic display. The two-dimensional/three-dimensional mode switching electronic display according to claim 11, wherein the light guiding body is located at a position between the planar light emitting surface of the planar backlight and the light valve array, and the light guiding The body and the multi-beam grid array transmit light emitted by the planar backlight in the first mode. The two-dimensional/three-dimensional mode switching electronic display according to claim 11, wherein the planar backlight comprises a diffuser adjacent to the planar light emitting surface, the diffuser is for scattering the emitted light . The two-dimensional/three-dimensional mode switching electronic display according to claim 13 of the patent application, wherein the planar backlight comprises a wedge-shaped light guiding body, the wedge-shaped light guiding body has a light-collecting layer, and the light-harvesting layer is light-receiving The wedge-shaped light guide is extracted from the wedge-shaped light guide body, and the extracted light is redirected through the diffuser to become emitted light. The two-dimensional/three-dimensional mode switching electronic display according to claim 11, wherein the light guiding system guides the light guiding beam to a collimated light beam at a non-zero value conduction angle. The two-dimensional/three-dimensional mode switching electronic display according to claim 11, wherein the multi-beam diffraction grating of the multi-beam diffraction grating array is a 绕-type diffraction grating, and the 啁The 绕-type diffraction grating includes one of a plurality of curved grooves and a plurality of curved ridges spaced apart from each other. The two-dimensional/three-dimensional mode switching electronic display according to claim 11, further comprising a light source optically coupled to an input end of the light guiding body, the light source including the input end along the light guiding body A plurality of light emitters are provided to provide a corresponding plurality of the light beams that are guided in the light guide. Switching the electronic display according to the two-dimensional/three-dimensional mode described in claim 17 wherein the light emitters comprise a first light emitter for emitting red light and a second light for emitting green light The transmitter, and a third light emitter for emitting blue light, the two-dimensional/three-dimensional mode switching electronic display is a color two-dimensional/three-dimensional mode that is a switched electronic display. The two-dimensional/three-dimensional mode switching electronic display according to claim 11, further comprising a switchable absorption layer between the planar backlight and the light guide, the switchable absorption layer is used to make the planar backlight The plate passes through the emitted light of the first mode and absorbs light from the second mode of the light guide. A method of providing backlighting for a two-dimensional/three-dimensional electronic display having a two-dimensional/three-dimensional switching mode, the method comprising: emitting a first switching mode of light from a light emitting surface of a first planar backlight; Using a multi-beam diffraction grating to couple a portion of a light beam guided by a second switching mode in a planar light guide of a second planar backlight to be provided away from the second planar backlight Directionally and coupling out a plurality of beams oriented in a plurality of major angular directions corresponding to different three-dimensional views of the two-dimensional/three-dimensional electronic display; wherein the second planar backlight is light emitted from the first planar backlight Passing through the second planar backlight, and re-emitting the emitted light in the first switching mode. A method for providing a backlight for a two-dimensional/three-dimensional electronic display having a two-dimensional/three-dimensional switching mode according to claim 20 of the patent application, further comprising a non-zero in the flat light guide of the second planar backlight The value conduction angle directs the light and the guided beam is a collimated beam. A method for providing backlighting for a two-dimensional/three-dimensional electronic display having a two-dimensional/three-dimensional switching mode according to claim 21, wherein the guiding beam comprises a plurality of beams of different colors, the beams of different colors Conducted in the planar light guide with a corresponding and different color-specific non-zero value conduction angle. A method for providing backlighting for a two-dimensional/three-dimensional electronic display having a two-dimensional/three-dimensional switching mode according to claim 20, wherein the multi-beam diffraction grating is a linear 绕-type diffraction grating, And the linear 绕-type diffraction grating includes one of a plurality of curved grooves and a plurality of curved ridges spaced apart from each other. A method for providing backlighting for a two-dimensional/three-dimensional electronic display having a two-dimensional/three-dimensional switching mode according to claim 20, further comprising modulating emitted light in the first switching mode through a light valve and The coupled light beams in the second switching mode, the modulated emitted light system forms the two-dimensional/three-dimensional electricity The two-dimensional pixels of the sub-display, and the modulated coupling out of the beam form a three-dimensional pixel of the two-dimensional/three-dimensional electronic display. A method for providing backlights for a two-dimensional/three-dimensional electronic display having a two-dimensional/three-dimensional switching mode according to claim 20, further comprising selectively blocking the second planar backlight with an active light absorbing layer The light in the second switching mode is emitted from the direction of the first planar backlight. A method for providing backlighting for a two-dimensional/three-dimensional electronic display having a two-dimensional/three-dimensional switching mode according to claim 20 of the patent application, further comprising operating a second/three-dimensional electronic display in the first switching mode A portion and operating another portion of the two-dimensional/three-dimensional electronic display in the second switching mode.