CN113167941B

CN113167941B - High brightness retro-reflector for static and switchable image displays

Info

Publication number: CN113167941B
Application number: CN201980072511.5A
Authority: CN
Inventors: 洛恩·A·怀特黑德
Original assignee: Wuxi Keling Display Technology Co ltd
Current assignee: Wuxi Keling Display Technology Co ltd
Priority date: 2018-11-06
Filing date: 2019-11-05
Publication date: 2023-11-14
Anticipated expiration: 2039-11-05
Also published as: CN113167941A; WO2020097095A1

Abstract

Reflective displays are typically less bright. A novel retro-reflector formed of linear prismatic structures has a graded microstructure array based on total internal reflection and opposing specular reflective surfaces, potentially replacing conventional retro-reflectors. Almost all of the incident light is reflected back to the viewer, resulting in a brighter display. The novel retro-reflectors described herein may be used in static display signage and electronically switchable displays.

Description

High brightness retro-reflector for static and switchable image displays

The present disclosure claims priority to U.S. provisional application serial No. 62/756,186 (titled "novel high brightness retro-reflector (Novel High Brightness Retroreflector for Static and Switchable Image Displays) for static and switchable image displays"), filed on 11/6 2018, the description of which is incorporated herein in its entirety.

Technical Field

The disclosed embodiments relate generally to reflective image displays. In one embodiment, the present disclosure relates to a novel hybrid retro-reflector. In another embodiment, the present disclosure relates to a hybrid specular/total internal reflection retro-reflective display for a static image display. In yet another embodiment, the present disclosure relates to a hybrid specular/total internal reflection retro-reflective display for a switchable image display.

Background

Conventional retroreflective static traffic sign consists essentially of two basic types of designs. The first conventional design includes high refractive index glass beads embedded in a film. The beads further have a metallic light reflective coating on opposite sides of the beads. There are health hazards in the manufacture and application of glass beads. For example, to obtain a high refractive index, the beads contain heavy metals. Additional safety measures must be taken for the relevant workers. This greatly increases the cost of manufacturing the beads and the retroreflective film due to the added manufacturing steps and safety measures.

A second type of conventional retroreflective signage design includes a microreplicated corner cube retroreflector. The corner cube sign includes a corner cube structure having an air gap behind it to allow total internal reflection.

Other signage and display applications use reflective rather than retroreflective display technology. Conventional microencapsulated electrophoretic displays, e.g. electronic ink based displays, characteristically reflect light in a white state in a so-called Lambertian (Lambertian) manner. In the white state, the reflected light is uniformly radiated in all directions with the same brightness. Thus, most of the reflected light is not reflected back to the viewer, limiting the perceived brightness of the display.

Fig. 1 schematically illustrates a conventional microencapsulated electrophoretic display, which illustrates lambertian reflection in a white state. Specifically, fig. 1 shows a display 100 having a microcapsule layer 102 that contains light-absorbing black particles 104 and light-reflecting particles 106. The display 100 is shown in a white or reflective state in which the light reflective particles 106 are located on an outward surface of the display 100 facing the viewer 108.

Dashed line 120 represents an incident light beam, where the light beam is nearly perpendicular to the outward facing surface of display 100. As shown by the plurality of light reflection lines 122, the light is reflected in all directions in a lambertian manner. As shown in fig. 1, a significant amount of light is not reflected back to the viewer 108. This also prevents the addition of a color filter layer to form a color display due to the limited amount of light reflected back to the viewer. Accordingly, there is a need to address the shortcomings of conventional reflective switchable image displays.

Drawings

These and other embodiments of the present disclosure will be discussed with reference to the following exemplary and non-limiting illustrations, wherein like elements are numbered similarly, and wherein:

FIG. 1 schematically illustrates a conventional microencapsulated electrophoretic display illustrating a Lambertian reflection in a white state;

FIG. 2A schematically illustrates a novel retro-reflector that mixes specular and total internal reflection;

FIG. 2B schematically illustrates a transverse cross-section of the novel retro-reflector structure 200;

FIG. 2C schematically illustrates a top view of the novel retro-reflector structure 200;

fig. 2D schematically illustrates a longitudinal cross-section of the novel retro-reflector structure 200 facing the facet 206;

FIG. 2E schematically illustrates a longitudinal cross-section of the novel retro-reflector structure 200 facing the specularly reflective surface 208;

FIG. 2F illustrates a close-up view of a portion of the retro-reflector 200;

FIG. 3 schematically illustrates a cross-section of a portion of a novel retroreflective static display according to one embodiment of the present disclosure;

FIG. 4 schematically illustrates a cross-section of a portion of a hybrid TIR-specular reflector switchable image display;

fig. 5 schematically illustrates an embodiment of a portion of an active matrix thin film transistor array for driving a hybrid TIR-specular reflector based display; and

fig. 6 schematically illustrates an exemplary system for implementing embodiments of the present disclosure.

Detailed Description

Throughout the following description, specific details are set forth in order to provide a more thorough understanding to those skilled in the art. Well known elements may not have been shown or described in detail, however, to avoid unnecessarily obscuring the disclosure. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.

In an exemplary embodiment, the reflective structure comprises at least one light reflecting repeat unit, wherein the light reflecting repeat unit comprises a first facet (facet), a second facet, and a third facet, wherein incident light is reflected by total internal reflection (total internal reflection, TIR) when the first facet is in contact with a lower refractive index medium, wherein incident light is reflected by TIR when the second facet is in contact with a lower refractive index medium, and the third facet further comprises a reflective coating capable of specularly reflecting the incident light. In one embodiment, the reflective structure comprises a plurality of reflective repeat units, wherein the repeat units are arranged adjacent in a row-like manner. In another embodiment, the first facet and the second facet, which are reflected by TIR, are arranged orthogonal to each other. In another embodiment, the first facet and the second facet that reflect incident light by TIR are arranged orthogonal to the third facet that is capable of specular reflection. In an exemplary embodiment, the third facet includes a metallized specular reflective coating. In some embodiments, the third facet may include a partially diffuse reflective coating. In an exemplary embodiment, the light reflecting structure comprising one or more light reflecting repeat units further comprises a material having a refractive index greater than about 1.4. In some embodiments, the material may include a refractive index in the range of about 1.4 to 2.4. In an exemplary embodiment, TIR may be frustrated near the surface of the first facet or the second facet using a light absorbing material that moves into the evanescent wave region, such as a plurality of electrophoretic particles suspended in a liquid or air medium or an electrophoretic fluid.

In one embodiment, the retro-reflector comprises at least one prism, wherein the prism comprises a first facet and a second facet. In an exemplary embodiment, one of the facets is further configured with a smaller (smaller) prism extending along the orthogonal direction. The other facet is coated with a reflective material, such as a metal. In an exemplary embodiment, total Internal Reflection (TIR) may occur near the surface of smaller prisms while specular reflection may occur on metallized facets when in contact with a lower index medium. The retro-reflector may be referred to as a hybrid reflector combining TIR and specular reflection. In an exemplary embodiment, TIR may be suppressed near the surface of a smaller prism using a light absorbing material that moves into the evanescent wave region at the interface of a higher index prism and a lower index medium, such as a plurality of electrophoretic particles suspended in a liquid or air medium or electrophoretic fluid.

As used herein, a hybrid TIR-specular retroreflective display generally refers to a display that returns reflected light rays within a range of angles (approximately +/-40 °) of the incident direction primarily along the incident direction. The retro-reflective properties are the result of the fact that two facets may reflect light by TIR, the two facets being placed in a substantially orthogonal arrangement with respect to each other and substantially orthogonal to the opposing third specular reflective surface. Thus, the number of reflections that a ray undergoes before returning to the viewer is three, two by TIR and one by specular reflection. The reflection of TIR may be attenuated by moving an absorbing material or substance into the evanescent wave region near the facets and absorbing light or frustrating TIR. The mixing geometry is such that each reflected ray undergoes two reflections by TIR, which means that a significant attenuation of the reflected light can be obtained with only a moderate degree of suppression. The hybrid TIR-specular retroreflective displays described herein may be used in static image displays and electronically switchable image displays.

Fig. 2A schematically illustrates a novel retro-reflector structure that mixes specular and total internal reflection. The novel retro-reflector structure 200 in fig. 2A includes a sheet 202 having an outward facing surface 204. The sheet 202 may comprise glass. The sheet 202 may comprise a polymer. The sheet 202 may comprise a transparent polymer. In the illustrationIn an exemplary embodiment, the sheet 202 may include polycarbonate, acrylic, or a combination thereof. The sheet 202 may include polymethyl methacrylate or polyvinyl alcohol (PVA). In some embodiments, the sheet 202 may be flexible or conformable (flexibility may also be referred to as rollability or bendable, with the ability to bend without breaking). In some embodiments, the sheet 202 may have a thickness in the range of about 1-2000 iim. In an exemplary embodiment, the sheet 202 may have a thickness in the range of about 20-250 a. The sheet 202 may have a refractive index of about 1.4 or higher (higher). In some embodiments, the sheet 202 may include a material having a refractive index in the range of about 1.5-2.4. In other embodiments, the sheet 202 may comprise a material having a refractive index in the range of about 1.5-2.2. In an exemplary embodiment, the sheet 202 may have a refractive index of about 1.5-1.9. In certain other embodiments, the sheet 202 may be a material having a refractive index in the range of about 1.6-1.9. The sheet 202 may be composed of a substantially rigid, high refractive index material. The high refractive index polymer that may be used may further include a high refractive index additive such as a metal oxide. The metal oxide may include S1O2, zrC >2、ZnC>2. ZnO or TiC>2, and one or more of the following. In one embodiment, sheet 202 may include T1O2 dispersed in PVA. In an exemplary embodiment, the sheet 202 may include Zr0 dispersed in an acrylic polymer ₂ 。

The sheet 202 includes an outward facing surface 204. The inward surface of structure 200 in fig. 2A includes a first linear prismatic structure 212, the first linear prismatic structure 212 including facets 206 arranged in a substantially orthogonal manner. The linear prismatic sheeting is characterized by three perpendicular geometric planes: one plane is parallel to the sheeting itself, the second plane is perpendicular to the sheeting and parallel to the linear prisms, and the third plane is perpendicular to the sheeting and also perpendicular to the linear prisms. Facet 206 and linear prism 212 may be considered a hierarchical prism structure. The structure 200 further includes an adjacent surface 208 (represented by cross-hatching in fig. 2A-2E) that reflects light in a specular manner. The surface of the facet 206 may be arranged perpendicular to the surface 208. Surface 208 may include a thin specular reflective coating. In some embodiments, surface 208 may include a thin metal coating. The thin metal coating on surface 208 may include one or more of aluminum, silver, chromium, nickel, copper, or gold. In other embodiments, surface 208 may include a multilayer dielectric coating capable of specular reflection. In some embodiments, surface 208 may include a partially diffuse reflective coating. The partially diffuse reflective coating may comprise T1O2, teflon or other materials.

Fig. 2B schematically illustrates a transverse cross-section of the novel retro-reflector structure 200. The cross-sectional view in fig. 2B shows the outward facing surface 204 facing the viewer 210. The opposite or inward surface includes prismatic structures 212. The single prismatic structure 212 includes a pair of facets 206, the pair of facets 206 being arranged substantially perpendicular to each other and otherwise substantially perpendicular to the opposing adjacent specular reflective surfaces 208. In some embodiments, the width (denoted as W) of the facets 206 of the linear prismatic structures _f ) A width (denoted as W) that is less than (preferably less than about half, and more preferably less than about one-fourth) the smallest dimension of specular reflective surface 208 _Sf ). In other embodiments, the width of the facets 206 of the linear prismatic structures is less than about half the width of the smallest dimension of the specular reflective surface 208. In an exemplary embodiment, the width of each facet 206 of the linear prismatic structure is less than about one-fourth the width of the smallest (smallest) dimension of the specular reflective surface 208.

Prismatic structures 212 may be arranged in rows 214. The distance or spacing between rows of prismatic structures 212 may be represented by pitch 216 (represented by p in FIG. 2B), where pitch is the distance between where surfaces 206 and 208 meet. The row spacing 216 may be a substantially regular or random array. In some embodiments, the spacing 216 may be in the range of about 0.1 microns to about 5000 microns. In other embodiments, the spacing 216 may be in the range of about 1 micron to about 3000 microns. In other embodiments, the spacing 216 may be in the range of about 10 microns to about 1000 microns.

In some embodiments, the angle α formed between the surface of facet 206 and specular reflective surface 208 may be in the range of about 75 ° to about 105 °. In other embodiments, the angle α may be in the range of about 85 ° to about 95 °. In an exemplary embodiment, the angle α may be about 90 °, with the facet 206 being substantially orthogonal to the facet 208. In some embodiments, the angle β formed between the surface of facet 206 and specular reflective surface 208 and facing outer surface 204 may be in the range of about 75 ° to about 105 °. In other embodiments, the angle β may be in the range of about 85 ° to about 95 °. In an exemplary embodiment, the angle β may be about 90 °, with the facet 206 being substantially orthogonal to the facet 208.

The retro-reflector 200 shown in fig. 2B may also be described as including one or more prisms 212, where the prisms include a first facet 211, the first facet 211 further including a smaller prism having facets 206. Prism 212 includes a second facet 213 disposed orthogonally to the smaller prism of first facet 206 and further includes light reflective coating 208. The first facets 211 may be composed of a transparent material having a first refractive index and reflect incident light by total internal reflection when in contact with a medium at the surface of the prism 206 having a lower second refractive index. The light reflective coating 208 on the second facet 213 may include a metal, such as one or more of aluminum, silver, nickel, chromium, copper, or gold.

Fig. 2C schematically illustrates a top view of the novel retro-reflector structure 200. The top view illustrates how the facets 206 are perpendicular to each other and may be arranged in pairs 218. Pairs 218 of facets 206 are further arranged in rows 220. Rows 220 of facets 206 are separated by specular reflective surfaces 208. Rows 220 of facets 206 aligned in a direction substantially orthogonal to specular reflective surface 208 may form rows 214 of prismatic structures 212 (shown in FIG. 2B).

Fig. 2D schematically illustrates a longitudinal cross-section of the novel retro-reflector structure 200 facing the facet 206. In this view, a longitudinal section is formed between the row 220 of facets 206 and the specular reflective layer 208, wherein a direct view of the row 220 of facets 206 is exposed. This view further illustrates how facets 206 may be arranged in pairs 218. The angle between the pair of facets 206 is represented by angle γ. In some embodiments, the angle g may be in the range of about 75 ° to about 105 °. In other embodiments, the angle γ may be in the range of about 85 ° to about 95 °. In an exemplary embodiment, the angle γ may be about 90 °.

Fig. 2E schematically illustrates a longitudinal cross-section of the novel retro-reflector structure 200 facing the specularly reflective coating surface 208. In this view, a longitudinal section is formed between rows 220 of facets 206 and specular reflective layer 208, with a direct view of specular reflective surface 208 exposed.

Fig. 2F illustrates a close-up view of a portion of the retro-reflector 200. Portions of the retro-reflector 200 may also be referred to as light reflective repeat units 222. The retro-reflector may include one or more light reflecting repeat units 222. The repeating unit 222 includes first and second facets 206 of substantially the same size that are disposed at an angle γ that is substantially orthogonal to each other. The repeating unit 222 further includes a third facet that further includes the light reflective coating 208 and is substantially orthogonal to the first and second facets 206 (represented by angle a). In some embodiments, angle a may be in the range of about 75 ° to about 105 °. In other embodiments, the angle α may be in the range of about 85 ° to about 95 °. In an exemplary embodiment, the angle α may be about 90 °. The first and second facets 206 may be composed of a transparent material having a first refractive index and reflect incident light at the surface by Total Internal Reflection (TIR) when in contact with a medium having a lower second refractive index.

Fig. 2F illustrates a typical reflection pattern at the surface of facet 206 and light reflective coating 208. The following is an example pattern of retroreflection in hybrid retroreflector embodiment 200. Other reflection modes are also possible. Incident light rays 240, represented by dashed lines, enter structure 212, where the light reflects off first facet 206 by TIR at location 242. The light rays are reflected toward the second facet 206 at location 244 where the light rays again undergo TIR at the interface between the surfaces of the high refractive index material comprising the retro-reflector 200 with the lower refractive index medium (e.g., air). The light rays may then be reflected toward the specularly reflective layer 208, where the light rays are specularly reflected at location 246 as reflected light rays 248 toward the viewer 210 in the direction from which the incident light rays 240 originated. The described reflection modes illustrate the ability of the optical structure 200 to mix total internal reflection and specular reflection. The structure 200 incorporates a first prismatic linear structure comprising two orthogonal surfaces 206 that reflect light by total internal reflection, and an adjacent surface 208 that reflects light in a specular manner and is further aligned in an orthogonal manner with the facets 206. The geometric relationship between the three surfaces is chosen to ensure that after the last reflection, the light rays travel in the opposite direction to their direction of incidence. This geometry results in one of three reflection modes, in which light is back-reflected after three reflections, including two TIR reflections and one specular reflection: facet-mirror layer (illustrated in fig. 2F), facet-mirror layer-facet, or mirror layer-facet. Furthermore, the dimensions and orientation of the three surfaces are selected such that a substantial portion of light rays incident within a preferred range of near normal directions are able to undergo retro-reflection. The normal vectors of the surfaces of the linear prisms are substantially orthogonal to each other and are tilted by greater than 55 ° from the normal vector of the entire plane of incidence of the system. The retro-reflector design 200 described herein retro-reflects virtually all incident light within a useful viewing range of about +/-400.

Various current micro-fabrication techniques may be used to create the novel retro-reflector designs described herein. Such microfabrication techniques include one or more of the following: photolithography, shadow masking, chemical vapor deposition (chemical vapor deposition, CVD), physical vapor deposition (physical vapor deposition, PVD), plasma etching, reactive-ion etching (RIE), wet etching, polishing, electroplating, micro-molding, micro-extrusion, micro-stamping, micro-dicing, and chemical mechanical planarization (chemicalmechanical planarization, CMP).

Fig. 3 schematically illustrates a cross-section of a portion of a novel retroreflective static display according to one embodiment of the disclosure. The retro-reflective display embodiment 300 of fig. 3 includes a hybrid retro-reflector as described in fig. 2A-2E. The display 300 includes a transparent sheet 302 having an outward facing surface 304 that faces a viewer 306. Sheeting 302 includes facets 308 and a specular reflective layer 310 to form a prismatic structure as previously described. The prismatic structures are arranged in an array 312 of rows and columns.In an exemplary embodiment, the sheet 302 may comprise flexible glass or polymer. In an exemplary embodiment, the sheet 302 may comprise glass or polymer or a combination thereof having a thickness in the range of about 20-500 microns. The sheet 302 may include a polymer such as polycarbonate or polymethyl methacrylate or other acrylic polymer. In an exemplary embodiment, the sheet 302 may include a transparent polymer. In some embodiments, the sheet 302 may be flexible or conformable (flexibility may also be referred to as being crimpable or bendable, having the ability to bend without breaking). In some embodiments, the sheet 302 may have a thickness in the range of about 1-2000 μm. In an exemplary embodiment, the sheet 302 may have a thickness in the range of about 20-250 a. The sheet 302 may have a refractive index of about 1.4 or higher. In an exemplary embodiment, the sheet 302 may have a refractive index of about 1.5-1.9. In certain embodiments, the sheet 302 may comprise a material having a refractive index in the range of about 1.5-2.4. In certain other embodiments, the sheet 302 may be a material having a refractive index in the range of about 1.6-1.9. The sheet 302 may comprise a substantially rigid, high refractive index material. The high refractive index polymer that may be used may further include a high refractive index additive such as a metal oxide. The metal oxide may include Si0 ₂ 、Zr0 ₂ 、Zn0 ₂ ZnO or Ti0 ₂ One or more of the following.

The rear reflective display 300 may further include a rear support sheet 314. The back support sheet 314 may be one or more of metal, polymer, wood, or other materials. The sheet 314 may be one or more of glass, polycarbonate, polymethyl methacrylate (PMMA), polyurethane, acrylic, polyvinyl chloride (PVC), or polyethylene terephthalate (polyethylene terephthalate, PET). The sheet 314 may be rigid or flexible.

The retroreflective display embodiment 300 may further include a light reflective layer 316 positioned on the back support sheet 314. The light reflecting layer 316 may include a metal such as aluminum, chromium, nickel, copper, gold, or silver. The light reflecting layer 316 may be deposited by sputtering, vacuum depositionProduct or other methods. The light reflective layer 316 may be continuous or patterned. The light reflecting layer 316 may be a diffuse reflector and may include Ti0 ₂ Or Teflon (Teflon) ^TM ) One or more of the following.

The retro reflective display embodiment 300 may further include spacers 318. The spacers may maintain a substantially uniform separation distance or gap 320 between the sheet 302 and the layer 314. Spacer structures may be used to support the layers in the display. The spacer structure may be a circular or oval bead shape, a block shape, a cylindrical shape, a wall shape, or other geometric shape, or a combination thereof. The spacer structure may comprise glass, metal or polymer. The gap 320 may be filled with a liquid or gaseous medium 322. In an exemplary embodiment, the medium 322 may include ambient air or a gas such as argon or N ₂ Is a gas of (a) a gas of (b). In an exemplary embodiment, the refractive index of the medium 322 in the gap 320 may be less than the refractive index of the sheet 302. The medium 322 may have a refractive index in the range of about 1-1.5. In an exemplary embodiment, the ratio of the refractive index of the sheet 302 to the refractive index of the medium 322 may be in the range of about 1.05 to about 2.20.

The retroreflective display embodiment 300 may further include an adhesive layer 324. Adhesive layer 324 may be located behind back support sheet 314. In other embodiments, the adhesive layer 324 may be interposed between the light reflective layer 316 and the rear support 314 such that the rear support layer 314 may also act as a release sheet to expose the adhesive layer 324. Adhesive layer 324 may include a polymer. The adhesive 324 may include one or more of a solvent-based adhesive, an emulsion adhesive, a polymer dispersed adhesive, a pressure sensitive adhesive, a contact adhesive, a hot melt adhesive, a multi-component adhesive, an ultraviolet-violet (UV) curable adhesive, a thermal curable adhesive, a moisture curable adhesive, a natural adhesive, or any other synthetic adhesive.

The retroreflective display 300 may further include a release sheet 326. The release sheet 326 may comprise a material such that it can be easily removed, and thus the multilayer structure 300 may be laminated or adhered to any structure or location where a static semi-retroreflective display is desired. The display 300 may be placed on a traffic sign, wall, road, clothing, bicycle, motor vehicle, or other application where it may be desirable to have a reflective display. The release sheet 326 may comprise a polymer or paper.

The retroreflective display 300 may further include a transparent image layer 328. Layer 328 may be continuous or patterned to convey information to the viewer, such as one or more of pictures, letters, numbers, words, phrases, or signs. Layer 328 may include one or more colors. Image layer 328 may include at least one dye. Image layer 328 may impart at least one color to the display. Layer 328 may be adhered to display 300 by an optically clear adhesive (not shown) located between layer 328 and sheet 302.

The retroreflective display 300 may further include an optional transparent outer layer or coating 330. Layer 330 may be a protective layer. Layer 330 may protect the display from physical damage or ultraviolet light. The protective layer may also comprise at least one color in a continuous or patterned manner. Layer 330 may comprise a polymer or glass.

Display embodiment 300 may reflect light and display an image as follows. Incident light, represented in fig. 3 by ray 340, may pass through image layer 328, coating 330, and sheet 302. If the angle of the light to the interface is greater than the critical angle 6 _C Light ray 340 may undergo TIR at the interface of higher index refractive facet 308 and lower index medium 322. A small critical angle (e.g., less than about 50 °) is preferred at facet 308 because this provides a wide range of angles at which TIR may occur. Preferably, the air is located at a refractive index (eta ₃ ) And the facets 308 are comprised of a material having a refractive index (eta) preferably as large as possible ₁ ) Is a material of (3). The critical angle 9C is calculated by the following equation (equation 1):

in a first example mode of reflection, light ray 340 may be reflected by total internal reflection at facet 308 toward specular reflective surface 310, where the light ray may then be reflected back toward observer 306 as substantially backward reflected light ray 342. In a second example mode of light reflection, incident light rays 344 may pass through layers 328, 330 and sheet 302 toward specular reflective layer 310. Light rays 344 may then be specularly reflected toward the interface of higher refractive index facets 308 and lower refractive index medium 322. At this location, total internal reflection may occur at the first and second facets 308 where the light ray 344 reflects as a light ray 346 toward the viewer 306. In both exemplary reflective modes, light may be reflected from the first and second facets and the specular reflective layer such that three reflections occur each time the light is back-reflected in the display 300. Reflected light from the static display 300 enhances the display image to the viewer 306 through the image layer 328.

In some cases, it may be important to have a whiter, more diffuse appearance based on the application of the static display 300. The display 300 may include a light diffusing layer. The diffusing layer may be used to soften incident light or reflect light or reduce glare. The diffusion layer may comprise a flexible polymer. The diffusing layer may comprise frosted glass in a flexible polymer matrix. The diffusion layer may comprise a microstructured or textured polymer. The diffusion layer may include a 3MTM antiglare or antiglare film. The diffusion layer may comprise a 3m tg lr320 film (Mei Puer wood, minnesota) or an AGF6200 film. The diffusion layer may be located at one or more different locations within the display embodiments described herein. In one embodiment, the diffusion layer may be located above or below the image layer 328.

Another approach to creating a whiter, more diffuse appearance for the static display 300 is to add additives to the sheet 302. Additives having a size greater than the wavelength of light may be added to scatter incident light. The magnitude of the scattering can be controlled by the size and type of additive. For example, ti0 ₂ May be added and dispersed in the sheet 302. Ti0 ₂ May have an optimal size range so as not to block light from passing through the sheet 302, but to scatter enough light to produce a visually more attractive, whiter display.

FIG. 4 is a schematic illustrationA cross section of a portion of a hybrid TIR-specular reflector switchable image display is illustrated. The display 400 in fig. 4 includes a transparent sheeting 402, the transparent sheeting 402 further including an inward array 406 of hybrid prism linear structures 404, the hybrid prism linear structures 404 including facets 408 and opposing specular reflective surfaces 410, as previously shown in fig. 2A-2F and described herein. In some embodiments, the sheeting 402 and the hybrid prism linear structure 404 may be continuous sheeting of the same material. In other embodiments, the sheeting 402 and the hybrid prism linear structure 404 may be separate layers and comprise different materials. In an exemplary embodiment, the sheeting 402 and the hybrid prism linear structure 404 may include substantially the same refractive index or different refractive indices. In an exemplary embodiment, the sheet 402 may comprise flexible glass. In an exemplary embodiment, the sheet 402 may comprise glass having a thickness in the range of about 20-250 microns. The sheet 402 may include a flexible glass, such as SCHOTT AF eco or->T eco ultra-thin glass. The sheet 402 may include a transparent polymer, such as polycarbonate, polymethyl methacrylate, or other acrylic polymer. In an exemplary embodiment, the sheet 402 may comprise a flexible polymer.

Sheeting 402 includes facets 408 and specular reflective surface 410 to form hybrid prism linear structure 404 as previously described. The hybrid prism linear structure 404 may be arranged in an inward array 406 of rows and columns. In an exemplary embodiment, the sheet 402 may comprise flexible glass or polymer. In an exemplary embodiment, the sheet 402 may comprise glass or polymer or a combination thereof having a thickness in the range of about 20-500 microns. In an exemplary embodiment, the sheet 402 may comprise a transparent polymer. In some embodiments, the sheet 402 may be flexible or conformable (flexibility may also be referred to as being crimpable or bendable, having the ability to bend without breaking). In some embodiments, the sheet 402 may have a thickness of between about 1-2A thickness in the range of 000 pm. In an exemplary embodiment, the sheet 402 may have a thickness in the range of about 20-250 pm. The sheeting 402 and the hybrid prism linear structure 404 may have a refractive index of about 1.4 or higher. In an exemplary embodiment, the sheet 402 may have a refractive index of about 1.5-1.9. In certain embodiments, the sheet 402 may comprise a material having a refractive index in the range of about 1.5-2.4. In some embodiments, the sheet 402 may include a material having a refractive index in the range of about 1.5-2.2. In certain other embodiments, the sheet 402 may be a material having a refractive index of about 1.6-1.9. The sheet 402 may comprise a substantially rigid, high refractive index material. The high refractive index polymer that may be used may further include a high refractive index additive such as a metal oxide. The metal oxide may include Si0 ₂ 、Zr0 ₂ 、Zn0 ₂ ZnO or Ti0 ₂ One or more of the following.

The display embodiment 400 in fig. 4 may include a color filter array layer 412. Color filter array layer 412 may be located on an outward surface of sheet 402 facing viewer 414. In an exemplary embodiment, color filter array layer 412 may be located between sheet 402 and inward array 406. The color filter array layer 412 may include one or more of red (R), green (G), blue (B), white (W), transparent, black, cyan, magenta, or yellow sub-pixel filters. In an exemplary embodiment, the color filter array layer 412 may be one or more of rigid, flexible, or conformable.

In an exemplary embodiment, each hybrid prism linear structure 404 may be substantially aligned with a single sub-color filter. In an exemplary embodiment, the color filter array layer 412 may include PenTile of sub-pixel color filters ^TM An array. Color filter array layer 412 may include PenTile of sub-pixel filters ^TM PenTile for RGBG array or sub-pixel color filter ^TM One or both of the RGBW arrays. The sub-color filters may be arranged such that an exemplary pixel may include, for example, three different sub-color filters (e.g., red, green, and blue). Thus, depending on the application, the pixel may reflect one of red, green and blue.

In FIG. 4May include at least one barrier layer 414. The barrier layer 414 may be transparent. The barrier layer 414 may be one or more of rigid, flexible, and conformable. The barrier layer 414 may be located in various locations within the hybrid retro-reflector based display embodiments described herein. The barrier layer 414 may serve as one or more of a gas barrier or a moisture barrier, and may be hydrolytically stable. The barrier layer 414 may be one or more of a flexible or conformable polymer. The barrier layer 414 may include one or more of polyester, polypropylene, polyethylene terephthalate, polyethylene naphthalate or copolymer, or polyethylene. The barrier layer 414 may comprise glass. The barrier layer 414 may include one or more of a chemical vapor deposition (chemical vapor deposited, CVD) or sputter coated ceramic-based film on a polymer substrate. The ceramic may include one or more of AI2O3, S1O2, or other metal oxides. The barrier layer 414 may include one or more of the following: a Vitriflex barrier film; ing Weida (Invista)A barrier resin; japanese relief printing Co (Toppan) GL ^TM Barrier films GL-AEC-F, GX-P-F, GL-AR-DF, GL-ARH, GL-RD; celplast->CPT-036, CPT-001, CPT-022, CPA-001, CPA-002, CPP-004, CPP-005 Silica (SiO) _x ) A barrier film; celplast->An aluminum oxide (AlOx) coated transparent barrier film; celplast->T AlOx-polyester film; />CBH or +.>CBLH is a biaxially oriented transparent barrier polypropylene film.

The display embodiment 400 in fig. 4 may include a diffusion layer 416. The diffusion layer 416 may be used to soften incident or reflected light, or reduce glare. The diffusion layer 416 may comprise a flexible polymer or glass. The diffusion layer 416 may be one or more of rigid, flexible, and conformable. The diffusion layer 416 may include ground glass in a flexible polymer matrix. The diffusion layer 416 may include a microstructured or textured polymer. The diffusion layer 416 may include Minnesota mining and manufacturing company (3M) ^TM ) An anti-flicker or anti-glare film. The diffusion layer 416 may include 3M ^TM GLR320 membranes (Mei Puer woods, minnesota (maplewiod)) or AGF6200 membranes. The diffusion layer 416 may be located at one or more different locations within the display embodiment 400 in fig. 4.

In some embodiments, the display embodiment 400 in fig. 4 may include at least one optically clear adhesive (optically clear adhesive, OCA) layer 418. The OCA layer 418 may be one or more of a rigid, flexible, or conformable polymer. OCAs can be used to adhere display layers together and optically couple the layers. TIR-based display embodiment 400 in fig. 4 may include an optically clear adhesive layer that further includes one or more of the following: 3M ^TM Optically clear adhesive 3M ^TM 8211、3M ^TM 8212、3M ^TM 8213、3M ^TM 8214、3M ^TM 8215、3M ^TM OCA 8146-X、3M ^TM OCA 817X、3M ^TM OCA 821X、3M ^TM OCA 9483、3M ^TM OCA 826XN or 3M ^TM OCA 8148-X、3M ^TM CEF05XX、3M ^TM CEF06XXN、3M ^TM CEF19XX、3M ^TM CEF28XX、3M ^TM CEF29XX、3M ^TM CEF30XX、3M ^TM CEF31、3M ^TM CEF71XX, lintec MO-T020RW, lintec MO-3015UV series, lintec MO-T015, lintec MO-3014UV2+, lintec MO-3015UV.

The display 400 in fig. 4 may include a front light system 420 having an outer surface 422 facing the viewer 414. The front light system 420 may include a light source 424 to emit light through an edge of the light guide 426. The light source 424 may include one or more of a light emitting diode (light emitting diode, LED), a cold cathode fluorescent lamp (cold cathode fluorescent lamp, CCFL), or a surface mount technology (surface mounted technology, SMT) incandescent lamp. In an exemplary embodiment, the light source 424 may define an LED whose output light emanates from refractive or reflective optical elements that concentrate the output emission of the diode over a compressed range of angles to the edge of the light guide 426. In an exemplary embodiment, the front light system 420 may include an angle transformer (not shown). In some embodiments, the light source 424 may be optically coupled to the light guide 426. The front light system 420 may be flexible or rigid.

The light guide 426 may comprise one or more of a rigid, flexible, or conformable polymer. The light guide 426 may include more than one layer. The light guide 426 may include one or more continuous light-guiding sublayers that are parallel to each other. The light guide 426 may include at least a first light-guiding sub-layer (not shown) forming a transparent bottom surface. The light guide 426 may include a second sub-layer that forms a transparent top or outer surface. The light guide 426 may include a third sub-layer that forms a central transparent core. The refractive indices of the sub-layers of the light guide 426 may differ by at least 0.05. Multiple sublayers may be optically coupled.

In an exemplary embodiment, the light guide 426 may include an array of light extractor elements (not shown). The light extractor element may be one or more of a rigid, flexible or conformable polymer. The light extractor element may comprise one or more of the following: light scattering particles, dispersed polymer particles, inclined prismatic facets, parallel prismatic grooves, curvilinear prismatic grooves, curved cylindrical surfaces, conical indentations, spherical indentations, aspherical indentations or air pockets. The light extractor elements may be arranged such that they redirect light in a substantially perpendicular direction to the sheet 402 with a non-lambertian narrow angular distribution. In other embodiments, the light extractor elements may be arranged such that they redirect light to the sheet 402 at a slightly off-axis angle such that fresnel and other undesirable reflections are reflected away from the viewer. The light guide 426 may include a diffuse optical haze. The light guide system in a display embodiment may include an FLEX front light (FLEx Front Light Panel) manufactured by FLEX Lighting (Chicago, IL). Light guide 426 may comprise an ultra-thin flexible light guide film manufactured by Nanocomp Oy corporation (leemer, finland).

The sheet 402 may further include a front electrode layer 428 on the surface of the facet 408 or on the facet 408 and the specular reflective surface 410. The front electrode layer 428 may be one or more of rigid, flexible, or conformable. The front electrode layer 428 may include a transparent conductive material such as Indium Tin Oxide (ITO), bei Tong (Baytron ^TM ) Or conductive nanoparticles, silver wires, metal nanowires, graphene, nanotubes, or other conductive carbon allotropes, or a combination of these materials dispersed in a substantially transparent polymer. The front electrode layer 428 may include a transparent conductive material that further includes silver nanowires manufactured by C3Nano (Hayward, CA, USA). The front electrode layer 428 may include C3Nano ActiveGrid ^TM And conductive ink.

The display embodiment 400 in fig. 4 may further include a rigid, flexible, or conformable back support layer 430. The rear support layer 430 may be one or more of metal, polymer, wood, or other materials. The rear support layer 430 may be one or more of glass, polycarbonate, polymethyl methacrylate (PMMA), polyurethane, acrylic, polyvinyl chloride (PVC), polyimide, or polyethylene terephthalate (PET).

In an exemplary embodiment, the rear electrode layer 432 may be located on an inner surface of the rear support layer 430. The back electrode layer 432 may be rigid, flexible, or conformal. The rear electrode layer 432 may include a transparent conductive material or a non-transparent conductive material such as aluminum, silver, gold, or copper. The rear electrode layer 432 may be vapor deposited or electroplated. The back electrode layer 432 may be continuous or patterned. The rear electrode layer 432 may be integrated with the rear support layer 430. Alternatively, the rear electrode layer 432 may be positioned proximal to the rear support layer 430. In another embodiment, the back electrode layer 432 may be laminated or attached to the back support layer 430. The back support layer 430 may form a gap or cavity 434 between them along with the array layer of hybrid retroreflectors. The rear electrode layer 432 may include a thin film transistor (thin film transistor, TFT) array or a passive matrix array. The back electrode layer 432 may include a direct drive patterned electrode array or a segmented electrode array. The back electrode layer 432 may include an active matrix of organic field-effect transistors (FETs). The organic FET may include an active semiconductor layer of conjugated polymer or conjugated small molecule. The organic FET may include an organic dielectric layer in the form of a solution processed dielectric or a chemical vapor deposited dielectric. The back electrode layer 432 may include aluminum, ITO, silver, copper, gold, or other conductive materials. In one embodiment, the back electrode layer 432 may include an organic TFT. In other embodiments, the back electrode layer 432 may include an indium gallium zinc oxide (indium gallium zinc oxide, IGZO) TFT. The back electrode layer 432 may include low temperature polysilicon, low temperature polysilicon manufactured through a polyimide "lift-off" process, amorphous silicon on a flexible substrate manufactured by FlexEnable (Cambridge, unite kingdom), or TFTs on a flexible substrate, or those manufactured by FlexEnable and Merck (Darmstadt, germany).

In an exemplary embodiment, the rear electrode layer 432 may include a planarization layer (not shown). The planarizing layer may be used to smooth the surface of the back-plate drive electronics. The planarization layer may allow for the placement or formation of complete sidewalls or partial sidewalls on top of the planarization layer. The planarizing layer may be flexible and/or conformable. The planarizing layer may include a polymer. The planarizing layer may be deposited using a slot die coating process or a flexographic printing process. The planarization layer may include photoresist. The planarization layer may also be used as a dielectric layer. The planarization layer may include polyimide.

In some embodiments, the display 400 may be curved such that the display may be forced to be convex or concave or any other shape desired with respect to the viewer 414. In some embodiments, display 400 may be curved in more than one direction, for example in the form of an S-curve.

The display 400 may also be flexible, rollable, foldable, twistable, or impact resistant. The flexible display 400 may be flexible in nature such that the display may substantially maintain optimal optical characteristics and performance in a curved or flexed state as in an unflexed or unflexed state. In an exemplary embodiment, the display 400 may maintain its original shape after removing the force causing the bending (or twisting). In yet another embodiment, the display 400 may remain in a deformed state even after the force causing the bending (or twisting) is removed. Display 400 may bend or flex for applications such as rollable or foldable displays for electronic newspapers and electronic signage. The display 400 may be placed on a curved or contoured surface, such as a dashboard, appliance, or even the skin of a human or animal, for medical diagnostic or other purposes.

The sidewalls 436 or spacer elements (not shown) may be implemented to help maintain a substantially uniform distance between the front electrode layer 428 and the back electrode layer 432 when the display embodiment 400 is in a non-flexed or flexed state. The sidewalls may also be referred to as cross walls, pixel walls or partition walls. The sidewalls 436 may limit particle settling, drifting and diffusion to improve display performance and bi-stability. In an exemplary embodiment, the sidewalls may substantially maintain a uniform gap distance between the front electrode layer 428 and the rear electrode layer 432 when the display flexes or bends. The sidewalls 436 may also act as a barrier to help prevent moisture and oxygen from entering the display. The sidewalls 436 may be located within a light modulation layer that includes electrophoretically mobile particles 440 and a medium 438.

The sidewall 436 may extend fully or partially from the front electrode, the rear electrode, or both the front and rear electrodes. The sidewalls 436 may comprise a polymer, metal, or glass, or a combination thereof. The sidewalls 436 may be of any size or shape. The sidewall 436 may have a circular cross-section.

The refractive index of the sidewalls 436 may be within about 0.01-0.2 of the refractive index of the hybrid prism linear structure 404. In an exemplary embodiment, the sidewalls 436 may be optically active. The sidewalls 436 may form holes or compartments to confine the electrophoretically mobile particles 440 suspended in the medium 438. The sidewalls 436 may be configured to form holes or cells, for example, in a square-like shape, triangular, pentagonal, or hexagonal shape, or a combination thereof.

The sidewalls 436 may comprise a polymeric material and be patterned by one or more conventional techniques, including photolithography, embossing, or molding. In some embodiments, display 400 includes sidewalls 436 that completely bridge gap or cavity 434. In other embodiments, display embodiment 400 may include portions of the sidewalls that only partially bridge gap or cavity 434. In some embodiments, the reflective image display may include a combination of sidewalls and portions of sidewalls that may fully or partially bridge the gap or cavity 434. In exemplary embodiments, the sidewalls 436 may include rigid, flexible, or conformable polymers. In other embodiments, sidewalls 436 may be substantially aligned with the color filter sub-pixels of color filter array layer 412.

In some embodiments, sidewalls 436 may be formed on top of rear dielectric layer 444, rear electrode layer 432, or rear support layer 430. In the example of fig. 4, sidewalls 436 are formed directly on rear dielectric layer 444. In other embodiments, the sidewalls may be formed as part of the inward array 406 of hybrid retro-reflector structures. Dielectric layer 448 may also be located on sidewalls 436. Sidewalls 436 may be formed on top of the planarization layer.

In an exemplary embodiment, the hybrid TIR-specular reflector based display 400 may be driven by backplane electronics including an active matrix thin film transistor array commonly used in liquid crystal displays (liquid crystal display, LCD). Fig. 5 schematically illustrates an embodiment of a portion of an active matrix thin film transistor array for driving a hybrid TIR-specular reflector based display. Backplane electronics embodiment 500 includes pixels 502An array that can be used to drive a flexible TIR-based display. The individual pixels 502 are highlighted by the dashed boxes in fig. 5. The pixels 502 may be arranged in rows 504 and columns 506 as shown in fig. 5, but other arrangements are possible. In an exemplary embodiment, each pixel 502 may include a single TFT 508. In the array embodiment 500, each TFT 508 is located at the upper left of each pixel 502. In other embodiments, the TFTs 508 may be placed at other locations within each pixel 502. Each pixel 502 may further include a conductive layer 510 to address each pixel of the display. Layer 510 may include ITO, aluminum, silver, copper, gold, bei Tong (Baytron) ^TM ) Or conductive nanoparticles, silver wires, metal nanowires, graphene, nanotubes, or other conductive carbon allotropes, or a combination of these materials dispersed in a polymer. The backplane electronics embodiment 500 may further include column conductors 512 and row conductors 514. Column conductors 512 and row conductors 514 may comprise a metal such as aluminum, silver, copper, gold, or other conductive metal. Column conductors 512 and row conductors 514 may comprise ITO. Column conductors 512 and row conductors 514 may be attached to TFTs 508. The pixels 502 are addressable in rows and columns. The TFT 508 may be formed using amorphous silicon or polysilicon. The silicon layer of TFT 508 may be deposited using plasma-enhanced chemical vapor deposition (plasma-enhanced chemical vapor deposition, PECVD). In an exemplary embodiment, each pixel may be substantially aligned with a single color filter in color filter array layer 412. Column conductors 512 and row conductors 514 may be further connected to integrated circuits and drive electronics to drive the display.

The display embodiment 400 may further include a low index medium 438, the low index medium 438 being located between the front electrode layer 428 and the back electrode layer 432 in the gap or cavity 434. The medium 438 may be air or a liquid. Medium 438 may be an inert low index fluid medium. The medium 438 may be a hydrocarbon. In some embodiments, the refractive index of medium 438 may be in the range of about 1-1.5. In other embodiments, the refractive index of medium 438 may be in the range of about 1.1-1.4. In an exemplary embodiment, the medium 438 may be a fluorinated hydrocarbon. In another exemplary embodiment, a mediumThe mass 438 may be a perfluorinated hydrocarbon. In an exemplary embodiment, the refractive index of the medium 438 is less than the refractive index of the sheeting 402 or hybrid prism linear structure 404. In other embodiments, the medium 438 may be a mixture of hydrocarbons and fluorinated hydrocarbons. In an exemplary embodiment, the medium 438 may include Fluorinert ^TM 、Novec ^TM 7000、Novec ^TM 7100、Novec ^TM 7300、Novec ^TM 7500、Novec ^TM 7700、Novec ^TM 8200. Electrowetting material, teflon (Teflon) ^TM )AF、CYTOP ^TM Or Fluoropel ^TM One or more of the following.

The medium 438 may further include one or more of a viscosity modifier or a charge control agent. Conventional viscosity modifiers include oligomers or polymers. The viscosity modifier may include one or more of styrene, acrylate, methacrylate, or other olefin-based polymers. In one embodiment, the viscosity modifier is polyisobutylene. In another embodiment, the viscosity modifier is a halogenated polyisobutylene.

The medium 438 may further receive a plurality of light absorbing electrophoretically mobile particles 440. The electrophoretically mobile particles 440 can comprise a first charge polarity and a first optical characteristic (i.e., color or light absorption characteristic). In some embodiments, medium 438 may further include a second plurality of electrophoretically mobile particles comprising a second charge of opposite polarity and a second optical characteristic. The electrophoretic mobile particles 440 may be formed of an organic material or an inorganic material or a combination of an organic material and an inorganic material. The particles may have a polymeric coating. The electrophoretic mobile particles 440 may include a coating of an organic material or an inorganic material or a combination of organic and inorganic materials. The electrophoretically mobile particles 440 can be a dye or pigment or a combination thereof. The electrophoretic mobile particles 440 may be at least one of carbon black, metal, or metal oxide. In an exemplary embodiment, the electrophoretically mobile particles 440 may include CuCr0 ₄ . In one embodiment, the electrophoretically mobile particles 440 shown in embodiment 400 of fig. 4 may be comprised of positively charged or negatively charged polarity, or a combination thereof. The electrophoretically mobile particles 440 can comprise weakly charged or uncharged particlesIs a particle of (2). The electrophoretically mobile particles 440 can be light-absorbing or light-reflecting or a combination thereof. The electrophoretic mobile particles 440 may also have light absorbing properties such that they may impart any color or combination of colors of the visible spectrum to give a particular shade or hue.

In another embodiment, display embodiment 400 may include a plurality of light absorbing particles 440 and a second plurality of light reflecting particles. The light reflecting particles may include white reflecting particles such as titanium dioxide (T1O 2). The light reflective particles may be about 200-300nm. This is a typical size of T1O2 particles used in the coatings industry to maximize light reflection characteristics. Larger or smaller sized particles may also be used. The light reflecting particles may further comprise a coating (not shown). The coating on the light reflective material may comprise an organic material or an inorganic material, such as a metal oxide. The coating may include an effective refractive index substantially similar to the refractive index of the medium 438. In some embodiments, the difference between the refractive index of the coating on the light reflective particles and the refractive index of the medium 438 may be about 40% or less. In other embodiments, the difference between the refractive index of the coating on the light reflective particles and the refractive index of the medium 438 may be about 0.5-40%.

In other embodiments, the medium 438 may also include an electrowetting fluid. In an exemplary embodiment, the electrowetting fluid may include a dye. The electrowetting fluid may move toward the hybrid prism linear structure 404 into the evanescent wave region to frustrate TIR. The electrowetting fluid may be away from the mixing prism linear structure 404 and away from the evanescent wave region to allow for total internal reflection. The electrowetting fluid may be silicone oil which can be pumped in and out of the aperture formed by the side wall via the small channel.

The display 400 may further include an optional dielectric layer 442 positioned on a surface of the transparent front electrode layer 428 and interposed between the transparent front electrode layer 428 and the medium 438. The display 400 may further include an optional rear dielectric layer 444 positioned on a surface of the rear electrode layer 432 and interposed between the rear electrode layer 432 and the medium 438.

The rear dielectric layer may be flexible and/or conformable. One or more optional dielectric layers may be used to protect one or both of the front electrode layer 428 or the back electrode layer 432. In some embodiments, the dielectric layer 442 on the front electrode layer 428 may include a different composition than the dielectric layer 444 on the back electrode layer 432. In an exemplary embodiment, the dielectric layers 442, 444 may include two or more sub-layers of dielectric material.

The sublayers may comprise different materials. For example, front dielectric layer 442 or back dielectric layer 444 may include Si0 ₂ A sub-layer and a polyimide second sub-layer. The dielectric layer may be substantially uniform, continuous, and substantially free of surface defects. The thickness of the dielectric layer may be at least about 0.05nm (i.e., about a monolayer) or thicker. In some embodiments, the dielectric layer thickness may be in the range of about 1-300 nm. In other embodiments, the dielectric layer thickness may be in the range of about 1-200 nm. In other embodiments, the dielectric layer thickness may be about 1-100nm. In other embodiments, the dielectric layer thickness may be about 1-50nm. In other embodiments, the dielectric layer thickness may be about 1-20nm. In other embodiments, the dielectric layer thickness may be about 1-10nm. The dielectric layer may include at least one pinhole. The dielectric layer may define a conformal coating and may be pinhole free or may have minimal pinholes. The dielectric layer may also act as a barrier to prevent moisture or gas ingress. The dielectric layer may have a high or low dielectric constant.

In some embodiments, the dielectric layer may have a dielectric constant in the range of about 1-30. In other embodiments, the dielectric layer may have a dielectric constant in the range of about 1-15.

The dielectric compound may be of the organic or inorganic type. The most common inorganic dielectric material is Si0, which is commonly used in integrated chips ₂ . The dielectric layer may be SiN, siN _x Or SiON. The dielectric layer may be Al0 _x Or A1 ₂ c> ₃ . The dielectric layer may be ceramic. The organic dielectric material is typically a polymer such as polyimide, fluoropolymer, polynorbornene, and hydrocarbon-based polymers that do not contain polar groups. The dielectric layer may be a polymer or a combination of polymers. The dielectric layer may be a combination of polymers, metal oxides, and ceramics. Dielectric layers 442, 444 may beTo include one or more of the following polyimide-based dielectrics daltons (Dalton) DL-5260T, TC-139, DL-2193, nissan SE-150, SE-410, SE-610, SE-3140N, SE-3310, SE-3510, SE-5661, SE-5811, SE-6414, SE-6514, SE-7492, SE-7992, or JSR AL-1054, AL-3046, AL22620, AL16301, AL 60720. In an exemplary embodiment, the dielectric layer includes parylene. In other embodiments, the dielectric layer may include halogenated parylene. The dielectric layers 442, 444 may include parylene C, parylene N, parylene F, parylene FIT, or parylene F TX. Other inorganic or organic dielectric materials or combinations thereof may also be used for the dielectric layer. One or more of the dielectric layers may be CVD, PECVD or sputter coated. One or more of the dielectric layers 442, 444 may be a solution coated polymer, a vapor deposited dielectric, a sputter deposited or a thermal or plasma enhanced ALD dielectric. Dielectric layer 444 may be conformal to the back electrode structure or may be used to planarize the electrode structure. Planarization of the electrode structure results in a smoother and more uniform surface, which may allow deposition of sidewalls having more uniform height and thickness.

In an exemplary embodiment, one or more dielectric layers 442 on front electrode layer 428 or one or more dielectric layers 444 on back electrode layer 432 in rigid, flexible, or conformable TIR-based image display 400 may be deposited by thermal or plasma enhanced atomic layer deposition (atomic layer deposition, ALD) methods. ALD may also be referred to as atomic layer epitaxy (atomic layer epitaxy, ALE), atomic layer growth (atomic layer growth, ALG), molecular layer epitaxy (molecular layer epitaxy, MLE), molecular layering (molecular layering, ML), and Atomic Layer CVD (ALCVD). In an exemplary embodiment, one or both of the dielectric layers 442, 444 may include ALD coated S1O2, siO _x 、SiN、SiN _x Or SiON. The dielectric layers 442, 444 may include other metal oxides, such as one or more of the following: AI2O3, a10 _x 、CaO、CuO、Er ₂ o ₃ 、Ga ₂ C> ₃ 、FlfCL、HfO _x 、InZnO、InGaZnO、La ₂ c> ₃ 、MgO、Nb ₂ O ₅ 、SC2O3、Sn0 ₂ 、Ta20s、T1O2、V _x Oy、Y2O3、Yb ₂ O ₃ 、ZnSnO _x ZnO or ZrC>2. The dielectric layers 442, 444 may include one or more metal nitrides, such as AIN, BN, gaN, siN, siN _x 、TaN、TaN _x TiAIN, tiN, WN or TiN _x . The dielectric layers 442, 444 may include a combination of metal oxide and metal nitride.

The disclosed display embodiments may employ at least one edge seal. The edge seal may prevent moisture or other environmental contaminants from entering the display. The edge seal may be a thermally, chemically or radiation curable material or a combination thereof. The edge seal may include one or more of epoxy, silicone, polyisobutylene, acrylate, or other polymer-based materials. In some embodiments, the edge seal may comprise a metallized foil. In some embodiments, the edge sealant may include, for example, S1O2 or A1 ₂ 0 ₃ Is a filler of (a). In other embodiments, the edge seal may be flexible or conformable after curing. In other embodiments, the edge seal may also act as a barrier to moisture, oxygen, and other gases.

The display embodiment 400 may further include a bias voltage source 446. The bias voltage source 446 may generate an electric field or electromagnetic flux in a gap or cavity 434 formed between the front electrode layer 428 and the back electrode layer 432. The flux may extend to any medium 438 disposed in the gap or cavity 434. The flux may move at least one of the electrophoretically mobile particles 440 toward one electrode and away from the opposing electrode. The flux may move one or more particles into or out of the evanescent wave region. The evanescent wave region is located approximately at the interface of the high index facet 408 and the lower index medium 438.

The bias voltage source 446 may be coupled to one or more processor circuits and memory circuits configured to change or switch the applied bias voltage in a predetermined manner and/or for a predetermined duration. For example, the processing circuitry may switch the applied bias to display characters on the display 400. The processing and memory circuitry may comprise hardware, software, or a combination of hardware and software. In an exemplary embodiment, one or more of the processing or memory circuits are flexible and/or conformable. For example, circuitry may be printed on a flexible substrate to achieve flexibility.

The display 400 may further include an ambient light sensor (ambient light sensor, ALS) 450 and a front light controller 452. The ALS 450 may be used to detect the amount of ambient light available and send information to the front light controller 452. The front light controller 452 may then control the output of the light sources 424 in the front light system 420 according to the amount of ambient light available. For example, under dim lighting conditions, such as at night, the ALS 450 may send information to the front light controller 452 to increase the amount of light emitted from the light sources 424 in the front light system 420. In bright conditions, such as on a beach on a sunny day, the ALS 450 may send information to the front light controller 452 to reduce the light output from the light sources 424 in the front light system 420. As the availability of ambient light increases, reflective displays appear brighter.

The display embodiment 400 may operate as follows. The electrophoretic mobile particles 440 may be moved toward the front electrode layer 428 by applying a bias voltage with a bias voltage source 446 that is opposite in polarity to the electrophoretic mobile particles 440 at the front electrode layer 428. This electrophoretically moves the electrophoretically mobile particles 440 into proximity with the front electrode layer 428, where they can enter the evanescent wave region and suppress total internal reflection as light is reflected between the facet 408 and the specularly reflective surface 410. This is shown to the right of the dashed line 454 and is illustrated by the incident light 456 absorbed by the electrophoretically mobile particles 440. This region of the display may appear dark to the viewer 414. Not all particles are located on the front electrode as shown in fig. 4. The placement of the electrophoretically mobile particles 440 in fig. 4 is for illustration purposes only.

As the particles move from the front electrode layer 428 toward the back electrode layer 432 (as shown to the left of the dashed line 454), incident light rays may be totally internally and specularly reflected at the hybrid prismatic linear structures 404 described herein. This is represented by first incident ray 458, which first incident ray 458 is totally internally reflected at facet 408, then reflected by specular surface 410, and then exits the display as reflected ray 460 toward viewer 414. Another representative reflection mode is illustrated by incident ray 462. Light ray 462 is first reflected by specular reflective surface 410 and then reflected toward facet 408, where it undergoes two TIR-based reflections before being reflected back as reflected light ray 464 to observer 414. In both reflection modes, the display pixels may appear white or bright to the viewer. It should be noted that the location of the electrophoretically mobile particles 440 at the rear electrode layer 432 is for illustration purposes only. The electrophoretically mobile particles 440 may be located just outside the evanescent wave region near the front electrode layer 428. The electrophoretic mobile particles 440 may be located anywhere within the gap or cavity 434 such that they do not substantially frustrate TIR when a white state is desired. The gray state may be formed by having a portion of the electrophoretically mobile particles 440 in the evanescent wave region at the front electrode layer 428 and another portion of the particles outside the evanescent wave region in the gap or cavity 434.

It is important to note that the geometry of the hybrid retro-reflector system described herein mixes TIR and specular reflections. TIR can be turned on and off by the movement of the electrophoretically mobile particles 440, whereas in this geometry specular reflection cannot be controlled by the movement of the absorbing material. The object of the present invention is to achieve a switchable display and a mixture of TIR and specular reflection is one of the reasons not apparent to the present invention. The specular component is required so that light is back-reflected as desired, while the specular component cannot be cut off. With a combination of TIR and specular surfaces, there are a large number of hierarchical microstructure arrangements. For a useful wide viewing angle range (in this case, about +/-40 degrees from normal incidence), the geometry of the hybrid retro-reflector invention described herein causes virtually all light incident within the useful viewing angle range to be retro-reflected, and for this geometry, frustration of TIR substantially eliminates all reflected light within that range by absorption. This is independent of the fact that there is a continuation of the specular reflection, since it cannot be absorbed. It is not obvious that for a display comprising non-switchable specular reflection, a sufficiently dark black state may be achieved. Another advantage of the invention described herein is that the geometry is due to each reflected ray undergoing two reflections by TIR. This means that a significant attenuation of the reflected light can be obtained, whereas the reflected light has only a moderate effect (duty).

It is important to note further that, roughly, the retro-reflector designs described herein may be similar to the prior art retro-reflector designs described in patents US2216325 (referred to as "rad, ryder") and US9575225 (referred to as "gold, kim"). There are significant differences that make the retro-reflector designs described herein unique and better suited for use with the static and switchable image displays also described herein. First, if the plastic structures described by Ryder and Kim were in contact with a fluorinated hydrocarbon fluid medium of suspended particles rather than air, their design would not be an effective retro-reflector. This is because the critical angle (9) of TIR is no longer satisfied at one or more of the structured facets (i.e. 206, 308, 408) _C ). Second, ryder and Kim do not describe the use of partial metallization to cause specular reflection at one or more of the structural facets. Finally, the retro-reflectors described by Ryder and Kim are not designed as switchable retro-reflectors, and therefore they do not describe methods of frustrating TIR or the use of fluorinated hydrocarbon fluids. Fluorinated hydrocarbon fluids are required to provide a medium that suspends the electrophoretic mobile particles and to provide a low refractive index fluid medium that contacts the higher refractive index retro-reflector. This allows a method of implementing a switchable display and allows a lower 6 _C To allow more light to be totally internally reflected, thus making the display brighter.

In a switchable image display (i.e., 400) that prevents reflection of incident light by frustrated TIR, a fluid such as a fluorinated hydrocarbon fluid is required to provide a medium that suspends the electrophoretic mobile particles 440. The retroreflective corner cube structures typically used in conventional retroreflective signage applications are not suitable for use in switchable image displays in which the corner cube structures are in contact with a fluorinated hydrocarbon fluid, a particulate suspension medium, and not air. This is because the critical angle (θ) of TIR is no longer satisfied at one or more structural facets _C ) As a result, incident light will not be receivedEffectively reflecting.

The various control mechanisms of the present invention may be implemented in whole or in part in software and/or firmware. The software and/or firmware may take the form of instructions contained in or on a non-transitory computer-readable storage medium. These instructions, in turn, may be read and executed by one or more processors to enable performance as described herein. The instructions may be in any suitable form, such as, but not limited to, source code, compiled code, interpreted code, executable code, static code, dynamic code, and the like. Such computer-readable media may include any tangible, non-transitory medium for storing information in one or more computer-readable forms, such as, but not limited to, read Only Memory (ROM); random access memory (random access memory, RAM); a magnetic disk storage medium; an optical storage medium; flash memory, etc.

In some embodiments, a tangible machine-readable non-transitory storage medium containing instructions may be used in conjunction with the disclosed display embodiments. In other embodiments, a tangible machine-readable non-transitory storage medium may be further used in conjunction with one or more processors.

Fig. 6 illustrates an exemplary system for controlling a display according to one embodiment of the present disclosure. In fig. 6, display 400 is controlled by a controller 640 having a processor 630 and a memory 620. Other control mechanisms and/or devices may be included in controller 640 without departing from the principles disclosed. The controller 640 may define hardware, software, or a combination of hardware and software. For example, controller 640 may define a processor that is programmed with instructions (e.g., firmware). Processor 630 may be an actual processor or a virtual processor. Similarly, memory 620 may be actual memory (i.e., hardware) or virtual memory (i.e., software).

Memory 620 may store instructions for driving display 400 that are executed by processor 630. The instructions may be configured to operate the display 400. In one embodiment, the instructions may include a biasing electrode associated with the display 400 through the power supply 650. When biased, the electrodes may cause the electrophoretic particles to move toward or away from a region proximal of the surface of the plurality of uncoated facets 408 at the inward surface of the front transparent sheet, thereby absorbing or reflecting light received at the inward surface of the front transparent sheet. By properly biasing the electrodes, particles (e.g., electrophoretically mobile particles 440 of fig. 4) can be moved into or near the evanescent wave region near the surface of the plurality of uncoated facets 408 at the inward surface of the front transparent sheet to substantially or selectively absorb or reflect incident light. Absorption of incident light produces a dark or colored state. By properly biasing the electrodes, particles (e.g., electrophoretically mobile particles 440 in fig. 4) can move away from the surface of the plurality of facets 408 at the inward surface of the front transparent sheet and out of the evanescent wave region in order to reflect or absorb incident light. Reflecting the incident light creates a bright state.

In the exemplary display embodiments described herein, they may be used in internet of things (Internet of Things, ioT) devices. The IoT devices may include a local wireless or wired communication interface to establish a local wireless or wired communication link with one or more IoT hubs or client devices. The IoT device may further include a secure communication channel to communicate with IoT services over the internet using a local wireless or wired communication link. IoT devices including one or more of the display devices described herein may further include sensors. The sensor may include one or more of temperature, humidity, light, sound, motion, vibration, proximity, gas, or thermal sensor. IoT devices including one or more of the display devices described herein may be connected to household appliances such as refrigerators, freezers, televisions (TVs), closed Caption TVs (CCTVs), stereo systems, heaters, ventilators, air conditioning (HVAC) systems, dust extraction robots, air cleaners, lighting systems, washing machines, dryers, ovens, fire alarms, home security systems, sink devices, dehumidifiers, or dishwashers. IoT devices including one or more display devices described herein may interface with health monitoring systems such as cardiac monitoring, diabetes monitoring, temperature monitoring, biochip transponders, or pedometers. IoT devices including one or more display devices described herein may interface with a transportation monitoring system such as an automobile, motorcycle, bicycle, scooter, watercraft, bus, or aircraft.

In the exemplary display embodiments described herein, they may be used in IoT and non-IoT applications such as, but not limited to, electronic book readers, portable computers, tablet computers, cellular phones, smart cards, signs, watches, wearable, military display applications, automotive displays, automotive license plates, shelf labels, flash memory drives, and outdoor billboards or outdoor signs that include displays. The display may be powered by one or more of a battery, solar cell, wind, generator, power outlet, AC (alternating current) power source, DC (direct current) power source, or other device.

In the exemplary static display embodiments described herein, they may be used as retroreflective garments, bicycle reflectors, motor vehicle reflectors, signs, road signs, outdoor billboards, traffic signs, wall signs, advertising signs, emergency signs, or outdoor signs.

It will be apparent to those skilled in the art of image display technology that many variations and modifications can be made to the preferred embodiment of the invention described above without departing from the scope of the invention. The preceding description is, therefore, exemplary rather than limiting.

The following examples are provided to further illustrate various embodiments of the disclosed principles. These examples are non-limiting.

Example 1 relates to a retro-reflector comprising: one or more light reflecting repeat units, wherein the repeat units comprise: a first facet; a second facet substantially orthogonal to the first facet; and a third facet further comprising a light reflective coating and being substantially orthogonal to the first facet and the second facet.

Example 2 relates to a retro-reflector according to claim 1, wherein the first facet and the second facet consist of a transparent material having a first refractive index and when in contact with a medium having a lower second refractive index and when the angle of the incident light on the first facet or the second facet exceedsCritical angle 6 _C When the incident light is reflected by total internal reflection.

Example 3 relates to the retro-reflector according to example 1, wherein the light reflective coating comprises a metal.

Example 4 relates to the retro-reflector according to example 1, wherein the light reflective coating comprises aluminum, silver, copper, gold, nickel, or chromium.

Example 5 relates to the retro-reflector according to example 2, wherein the first refractive index is in a range of 1.5-2.2.

Example 6 relates to the retro-reflector according to example 2, wherein the first refractive index is in a range of 1.6-1.9.

Example 7 relates to the retro-reflector according to example 1, wherein an angle is formed between the first facet and the second facet, and the angle is in a range of 85-95 degrees.

Example 8 relates to the retro-reflector according to example 1, wherein an angle is formed between the first facet and the third facet, and the angle is in a range of 85-95 degrees.

Example 9 relates to the retro-reflector according to example 1, wherein an angle is formed between the second facet and the third facet, and the angle is in a range of 85-95 degrees.

Example 10 relates to a retro-reflector comprising: one or more prisms, wherein the prisms further comprise: a first facet, the first facet further comprising smaller prisms; and a second facet disposed orthogonally to the smaller prism of the first facet and further comprising a specular reflective coating.

Example 11 relates to the retro-reflector according to example 10, wherein the first facet comprises a transparent material having a first refractive index, and when in contact with a medium having a lower second refractive index and when an angle of incident light on the first facet exceeds a critical angle 6 _C When the first facet totally internally reflects incident light.

Example 12 relates to the retro-reflector of example 10, wherein the light reflective coating comprises a metal.

Example 13 relates to the retro-reflector of example 10, wherein the light reflective coating comprises aluminum, silver, copper, gold, nickel, or chromium.

Example 14 relates to the retro-reflector of example 10, wherein an angle is formed between the first facet and the second facet, and the angle is in a range of 85-95 degrees.

Example 15 relates to a total internal reflection ("totally internally reflective, TIR") display, comprising: a transparent front sheet; a plurality of light reflecting repeat units positioned over the inward facing surface of the transparent front sheet, each repeat unit comprising a first facet, a second facet, and a third facet, wherein the first facet and the second facet are comprised of a material having a first refractive index; a light reflective coating on the third facet of each light reflective repeat unit; one or more front electrodes formed over the light reflecting repeat units; one or more rear electrodes positioned to form a gap with the front electrode; and a plurality of electrophoretically mobile particles suspended in a medium disposed in the gap, wherein the medium has a second refractive index lower than the first refractive index of the material comprising the first and second facets.

Example 16 relates to the TIR display of example 15, further comprising a plurality of color filter subpixels positioned above the outward facing surface of the transparent front sheet.

Example 17 relates to the TIR display of example 15, further comprising a dielectric layer positioned over one or both of the front electrode and the back electrode.

Example 18 relates to the TIR display of example 15, further comprising at least one pixel wall positioned in the gap of the transparent front sheet.

Example 19 relates to the TIR display of example 15, wherein the electrophoretically mobile particles are suspended in a fluorinated medium.

Example 20 relates to the TIR display of example 15, further comprising a bias source to apply a bias across the gap between the front electrode and the back electrode to move at least one electrophoretically mobile particle near the surface of the first facet and the second facet to frustrate total internal reflection of light.

Example 21 relates to the TIR display of example 15, wherein the material having the first refractive index comprises a refractive index in a range of 1.5-2.2.

Example 22 relates to the TIR display of example 15, wherein the material having the first refractive index comprises a refractive index in a range of 1.6-1.9.

Example 23 relates to the TIR display of example 15, further comprising at least one dielectric layer on the front electrode or the back electrode.

Example 24 relates to the TIR display of example 15, further comprising a front light system.

Example 25 relates to the TIR display of example 15, further comprising a barrier layer.

Example 26 relates to the TIR display of example 15, further comprising an edge seal.

Example 27 relates to the TIR display of example 15, wherein an angle is formed between the first facet and the second facet, and the angle is in a range of 85-95 degrees.

Example 28 relates to the TIR display of example 15, wherein an angle is formed between the first facet and the third facet, and the angle is in a range of 85-95 degrees.

Example 29 relates to the TIR display of example 15, wherein an angle is formed between the second facet and the third facet, and the angle is in a range of 85-95 degrees.

Example 30 relates to a total internal reflection ("totally internally reflective, TIR") display, comprising: a transparent front sheet; a plurality of prisms positioned over the inward-facing surface of the transparent front sheet, wherein the prisms further comprise: a first facet further comprising smaller prisms and comprising a material having a first refractive index; a second facet disposed orthogonally to the smaller prism of the first facet and further comprising a light reflective coating; one or more front electrodes formed over the plurality of prisms; one or more rear electrodes positioned to form a gap with the front electrode; and a plurality of electrophoretically mobile particles suspended within a medium disposed within the gap, wherein the medium has a second refractive index lower than the first refractive index of the material comprising the first facets.

Example 31 relates to the TIR display of example 30, further comprising a plurality of color filter subpixels positioned above the outward facing surface of the transparent front sheet.

Example 32 relates to the TIR display of example 30, further comprising a dielectric layer positioned over one or both of the front electrode and the back electrode.

Example 33 relates to the TIR display of example 30, further comprising at least one pixel wall positioned in the gap of the transparent front sheet.

Example 34 relates to the TIR display of example 30, wherein the electrophoretically mobile particles are suspended in the fluorinated medium.

Example 35 relates to the TIR display of example 30, further comprising a bias source to apply a bias across the gap between the front electrode and the back electrode to move at least one electrophoretically mobile particle near the prismatic surface of the first facet to frustrate total internal reflection of light.

Example 36 relates to the TIR display of example 30, wherein the prism comprises a refractive index in a range of 1.5-2.2.

Example 37 relates to the TIR display of example 30, wherein the prism comprises a refractive index in a range of 1.6-1.9.

Example 38 relates to the TIR display of example 30, further comprising at least one dielectric layer on the front electrode or the back electrode.

Example 39 relates to the TIR display of example 30, further comprising a front light system.

Example 40 relates to the TIR display of example 30, further comprising a barrier layer.

Example 41 relates to the TIR display of example 30, further comprising an edge seal.

Example 42 relates to the TIR display of example 30, wherein an angle is formed between the first facet and the second facet, and the angle is in a range of 85-95 degrees.

Example 43 relates to a method for switching a TIR image display from a bright state to a dark state, comprising: applying a first non-zero voltage to attract the plurality of electrophoretically mobile particles toward a front electrode positioned above the light-reflective repeat unit; electrophoretically moving the particles into an evanescent wave region near a surface of the facet of the light reflecting repeat unit that does not include the light reflecting coating; and wherein total internal reflection of incident light is suppressed and light is absorbed by the electrophoretically mobile particles to form a dark state.

While the principles of the present disclosure have been illustrated with respect to the exemplary embodiments shown herein, the principles of the present disclosure are not limited thereto and include any modifications, variations or permutations thereof.

Claims

1. A retro-reflector, comprising:

A plurality of prisms, wherein the prisms further comprise:

a first facet further comprising a plurality of smaller prisms, and the smaller prisms having pairs of facets, the pairs of facets arranged in rows; and

a second facet disposed orthogonally to the smaller prism of the first facet and further comprising a light reflective coating;

wherein opposite sides of said second facets are respectively connected to said first facets of two adjacent ones of said prisms such that rows of said pairs of facets are separated by said second facets, when an incident light ray enters said prism, at least a portion of said incident light ray undergoes two total internal reflections at said pairs of facets, and is back-reflected after a third reflection at said second facets.

2. The retro-reflector according to claim 1, wherein the first facets are composed of a transparent material having a first refractive index and when in contact with a medium having a second, lower refractive index and when the angle of incident light on the first facets exceeds a critical angleWhen the first facet totally internally reflects the incident light.

3. The retro-reflector of claim 1, wherein the light reflective coating comprises a metal.

4. The retro-reflector according to claim 1, wherein the light reflective coating comprises aluminum, silver, copper, gold, nickel or chromium.

5. The retroreflector of claim 1, wherein an angle is formed between the first facet and the second facet, and the angle is in the range of 85-95 degrees.

6. A TIR display comprising:

a transparent front sheet;

a plurality of prisms positioned over an inward surface of the transparent front sheet, wherein the prisms further comprise:

a first facet further comprising a plurality of smaller prisms and comprising a material having a first refractive index, and the smaller prisms having pairs of facets arranged in rows;

one or more front electrodes formed over the plurality of prisms;

one or more rear electrodes positioned to form a gap with the front electrode; and a plurality of electrophoretically mobile particles suspended in a medium disposed in the gap, wherein the medium has a second refractive index lower than the first refractive index of the material comprising the first facets;

7. The TIR display of claim 6, further comprising a plurality of color filter sub-pixels positioned above an outward facing surface of the transparent front sheet.

8. The TIR display of claim 6, further comprising a dielectric layer positioned over one or both of the front electrode and the back electrode.

9. The TIR display of claim 6, further comprising at least one pixel wall positioned in the gap.

10. The TIR display of claim 6, wherein the electrophoretically mobile particles are suspended in a fluorinated medium.

11. The TIR display of claim 6, further comprising a bias source for applying a bias across the gap between the front electrode and the back electrode to move at least one electrophoretically mobile particle near a surface of the prism of the first facet to frustrate total internal reflection of light.

12. The TIR display of claim 6, wherein the prism comprises a refractive index in the range of 1.5-2.2.

13. The TIR display of claim 6, wherein the prism comprises a refractive index in the range of 1.6-1.9.

14. The TIR display of claim 6, further comprising at least one dielectric layer on the front electrode or the back electrode.

15. The TIR display of claim 6, further comprising a front light system.

16. The TIR display of claim 6, further comprising a barrier layer.

17. The TIR display of claim 6, further comprising an edge seal.

18. The TIR display of claim 6, wherein an angle is formed between the first facet and the second facet, and the angle is in a range of 85-95 degrees.

19. A method for switching a TIR image display from a bright state to a dark state, comprising:

applying a first non-zero voltage to attract a plurality of electrophoretically mobile particles toward a front electrode positioned over a plurality of prisms, the prisms including a first facet having a plurality of smaller prisms and a second facet disposed orthogonally to the smaller prisms and including a light reflective coating, wherein the smaller prisms have pairs of facets arranged in rows, opposite sides of the second facet being connected to the first facets of adjacent two of the prisms, respectively, such that the rows of pairs of facets are separated by the second facet;

When an incident ray enters the prism, at least part of the incident ray is reflected back after being totally internally reflected twice by the paired facets and reflected third times by the second facets; and

when the electrophoretically mobile particles enter an evanescent wave region near a surface of the first facet that does not include a light reflective coating; and is also provided with

Wherein total internal reflection of the incident light is suppressed and absorbed by the electrophoretically mobile particles to form a dark state.