WO2013153393A1 - Electronic display - Google Patents

Abstract

An electronic display comprising a multi- stable reflective LCD array (A) in an integral multilayer stack with at least one functional layer ( 10, 20, 30, 40, 50, B ) to provide a control function for the LCD array, the functional layer in electrical connection and/or communication with the LCD array directly or wirelessly layer upon layer for compliant association for manipulation together for storage, transportation and assembly of the electronic display in use.

Description

ELECTRONIC DISPLAY

This invention relates generally to electronic displays and more particularly to such displays used as digital signage such as part of billboards, information panels and the like.

Digital signage, such as used for advertising and public information on the streets and in other public locations is rapidly gaining popularity as the technology of displays advances, reducing the cost of digitally-addressable displays and making the technology more widely applicable.

It is envisaged that technology could soon reach cost points where is can be used as a substitute for paper in advertisements and notices in a multiplicity of locations such as billboards, bus-shelters, road signs and numerous other applications. A digital display will allow the message provider to change the image at will and save on changeover costs for example.

Many of these applications will be especially suited to the new display technologies which require very low levels of energy. This is because costs of the additional wiring associated with higher power digital signage can dissuade advertising agents from installing digital displays. Furthermore, many legislative and community groups are known to oppose the introduction of higher energy displays for reasons of consumption of power and 'light pollution', particularly in the case of LED-based displays.

Higher power displays are of course expensive to operate in terms of energy consumption. In contrast, bi-stable reflective LCD displays only require small amounts of power to change the image; when the image is not changing, the display will not consume power. The image can be changed many times per day and continuously moving imagery is not inconceivable. Furthermore, the reflective nature of the display means that it does not need a backlight, thereby eliminating another source of energy loss.

The low energy demands of the bi-stable reflective LCD display means that it is an attractive option to replace a static paper-based image on a simple billboard (taken to mean a notice or advertisement or any form of printed display material) on a direct like- for-like replacement basis. In accordance with aspects of the present invention there is provided an electronic display comprising a multi-stable reflective LCD array in an integral multi-layer and/or laminated stack with at least one functional layer to provide a control function for the LCD array, the functional layer in electrical connection and/or communication with the LCD array directly or wirelessly layer upon layer for compliant association for manipulation together for storage, transportation and assembly of the electronic display in use.

The reflective LCD array is configured whereby one or more of the multi-stable states limits or avoids or facilitates operation of the functional layer or one of the functional layers.

The manipulation may include rolling and/or folding. The manipulation may include association with presentation means such as a backing surface or a frame with or without an adhesive or other fastener.

The electronic display may be a billboard or signage or whiteboard or blackboard. The functional layer may be one or more of the following:- a) An antenna receiver typically in a flat panel form. The antenna receiver may be formed by at least part of a reflective surface of the bi-stable reflective LCD array. The antenna receiver may be part of a two-way transmitter receiver for communication with near field devices such as PDAs. The communication may be encrypted such as with Bluetooth. The antenna may be printed and/or etched to provide a secondary coil for inductive electrical charging. The antenna may be configured to monitor background r.f. radiation as a detector for vehicle approach. b) Metallised substrates co-formed with an electrolytic-impregnated matrix to form a battery.

c) Metallised substrates configured to provide a capacitor and a sensor sensitive to approach of a person and/or a vehicle and/or movement.

d) A film configured to be touch sensitive.

e) Integrated and/or discrete electrical components to provide the control function.

The components may be printed. The components may be semi-conductor layers. f) A static electricity function for adhesion to wall or other surfaces. The static electricity function may be limited to portions of the display. The portions may be edge portions and/or spaced portions. The portions may be electrically isolated from the remainder of the display. g) A printed relief or luminescent information surface. The surface may be removable from the remainder of the display.

h) A thermoelectric cooling layer to reduce the amount of heat the display is exposed to, for example from the sun.

The display may be associated with an external battery and/or accumulator and/or capacitor at least for initial activation. The display may include charging means for periodic charging of the display. The charging means may by inductive and/or by contact and/or by static electricity charging as the display is wiped for cleaning or otherwise.

The functional layer may include a light sensor. The light sensor may determine incident light upon the display whereby the control function can determine a level of electrical power generation. The control function can dependent upon the level of electrical power generation to determine which parts of the functional layer are functional. The control function can provide and maintain a record of incident light and/or electrical power generation. The record may be used to determine a necessary electronic display configuration for a location for such electronic displays thereafter in terms of necessary battery capacity and/or potential electrical power consumption by the functional layer and/or future charging top-up of the electronic display.

The LCD array and/or the functional layer may be formed by layer upon layer deposition. The layer upon layer deposition may be substantially continuous and/or as a roll and/or consistent across the display.

The LCD array and the functional layer may be configured in combination to have a substantially plastic nature.

The functional layer may have transparent windows overlapping the bi-stable reflective LCD array.

The LCD array and the functional layer may have a repeat pattern of functional zones substantially separable and operable from other functional zones. The LCD array and the functional layer in each functional zone may be co-dependent upon each other. The display may be severable about the functional zones.

The display may have an over-layer. The over-layer may be detachable as a protective cover. The over-layer may be integral with the display. The over-layer may demark areas of the display. The areas may be for attachment of the display. The areas may be for designation of parts of the functional layer and/or the LCD array. The over-layer may be photo-sensitive to darken or lighten as an indication of light exposure age.

It can therefore be envisaged that a display integrated with a functional layer such as a battery and a wireless receiver can operate completely autonomously, being affixed in the same locations as the paper equivalent and being addressed remotely from a suitable radio transmitter.

The display may further have a protective layer, e.g. a heat protective layer, in order to reduce the amount of heat the display is exposed to, for example from the sun, in order to prevent or limit the effects of solar flare and/or isotropic blackout, e.g. where heat from the sun's rays increases the temperature of the liquid crystal to the point where it is no longer homeotrophic, causing the display to turn black as the liquid crystal has no flexoelectric effect. The protective layer may comprise a polarising film or ultra-violet filtering film. Additionally or alternatively the protective layer may comprise a thermoelectric cooling layer, e.g. a Peltier film or mesh or wire layer or a Peltier or Seebeck or Thomson cooling system.

The display may further comprise an anti-glare portion or layer to minimise or reduce glare caused by light reflected by the display, for example scattered light reflected from the sun or vehicle headlights. The anti-glare portion or layer may be provided by an antiglare coating or sheet, for example a polyurethane coating or sheet. Alternatively the anti-glare portion or layer may be provided by polarising film. The polarising film may be orientated horizontally or substantially horizontal with respect to the display in order to improve the anti-glare properties of the anti-glare portion or layer.

The layers within the multi-layer and/or laminated stack of the liquid crystal may be separated by spacers, for example supports or walls or pillars or columns or props between each of the layers.

The display may be manufactured using roll-to-roll or reel-to-reel or web processing or manufacturing methods. Manufacture of the display may be computer-controlled in order to allow different panel sizes to be produced on the same film and nested. The spacers, electrodes and electronics of the display may be produced by printing or deposition methods, such as ink-jet printing or by embossing methods, for example soft- embossing.

The spacers or supports or walls or pillars or columns or props may be partially cured or toughened or hardened prior to positioning on the each of the layers. Once the correct gap has been attained between the layers, the spacers or supports or walls or pillars or columns or props may be fully cured or toughened or hardened.

Embodiments of the invention will now be described by way of example only with reference to the accompanying drawings in which:

Figure 1 is an exploded schematic illustration of part of an electronic display in accordance with aspects of the present invention;

Figure 2 is a schematic illustration of a display manipulated and attached to a wall;

Figure 3 is a schematic illustration of a display manipulated within a frame; and,

Figure 4 is a schematic illustration of a display rolled up for storage and/or transportation.

It is envisaged that additional functionality can be provided to realise further value from multi-stable or bi-stable reflective LCD display technology. Such functionality could include a photovoltaic cell to recharge the battery, sensing to detect the presence of people or vehicles and wireless intercommunication with personal mobile phones. Whilst the photovoltaic cell is clearly focussed on reducing the size of necessity for an integrated battery, additional functionality will enable the display to become very much more interactive with the viewing public and thus the broadcast message can be much more targeted.

Hitherto, most of this functionality would typically be integrated in a separate box which would be connected to the display or be embedded into the display structure itself. The parts are for the most part separate and/or side-by-side causing packaging problems and manufacturing difficulties. This separate box may then need to be connected to a local network, requiring additional installation costs. To provide some independence of operation a photovoltaic cell and its functionality would probably be provided by a separate panel, perhaps mounted above prior display systems; it will be understood that a PV panel needs light to function but multi-stable states interfere with light incident upon the PV panel.

So-called Out of the box' functionality is desirable - whereby the display is fitted onto a pre-existing location and where it starts to work immediately it has been fixed in the desired location. No further wiring should be required for this to be achieved. In the case of reflective LED bi-stable displays, the display will use pre-existing illumination at night and in the daylight, the display will charge its own battery from sunlight. Only a little sunlight will be required to start up an electronic display panel which has just been removed from its transport container or an initiation electrical charge provide for a few seconds or a short period of time to effectively switch the electronic display on..

Low cost displays are typically made from plastic i.e. non-glass flexible substrates which are known in the art as lower cost, thinner, lighter and more robust than glass. Concomitant with the low cost of the materials, the manufacturing process will also need to be low cost. In many industries, roll-to-roll or reel-to-reel or web manufacturing is seen as a more efficient manufacturing approach than a piecemeal approach with separate or side-by-side functional components which may require association/assembly together and the same is typically true for flexible display technology. Roll-to-roll or reel-to-reel or web manufacturing is a strong influence on the approach described in this document but the approach can also be applicable to displays made in rigid display panels. Roll-to-roll or reel-to-reel or web manufacturing means that displays can be mass produced as consistent units rather than with too bespoke display component patterns across the display. A display in accordance with aspects of the present invention may have at least some separation of the function of different parts of the display in a stack or layer upon layer through the depth of the display rather than side-by-side.

Fundamentally, advertising displays of the type described in this document are relatively large (may be over a metre in size) and are usually subjected to enough daylight, even when not pointing at the sun. It is therefore reasonable to consider co-laminating a photovoltaic means of generating power as a transparent substrate laminated to one of the front side substrates used in the manufacture of the display. This photovoltaic panel may be a separate layer or it may be derived from a coating on one of the other substrates used in the manufacturing of the panel such as the colour layer or the polarising layer on a typical LCD array display. Of the additional features as functional layers described in this document, it is apparent that many of these can also be formatted to be manufactured as another integral functional layer concurrently with the manufacturing of the display itself. For example,

• A rear reflective substrate of the reflective multi-stable or bi-stable LED array can be adapted or an additional substrate can be created to form a flat panel antenna receiver with which to receive signals from a remote base station which is further converted via an encryption module onto the displayed message at a local electronic display site or signage.

• The antenna panel can also be configured to operate as a 2-way transmitter receiver, the purpose of which is communicate with near-field devices such as personal mobile phones for personal advertising or messaging purposes or for example with the phone of an authorised person for the purpose of displaying an authorised message. All so-called push-messaging to the panel will be subject to encryption to prevent unwanted 'hijacking' of the message conveyed on the display panel and to ensure payment is received if necessary before display and possible vetting for content.

• The flat panel antenna may incorporate the printed format required to operate as the secondary coil in an inductive system when used for charging the battery, where sufficient daylight is not available for recharging, such as in a shopping mall.

• Separate large metallised substrates can be co-formed with an electrolytic- impregnated matrix to form a simple battery with which to power the display or store energy.

• A metallised substrate can be used as a capacitor-based sensor with which to detect the approach of a person or vehicle.

• A further front film can be developed to provide a touch-screen capability for interactive displays.

• The antenna can be used to monitor background r.f. radiation as a means to detect the approach of a vehicle in the middle distance, using the approach as a means for directing traffic or displaying a speed-related or safe-driving method.

• The electronic circuitry required to operate the display can be provided on a further layer, largely as printed components. Only a minimal number of discrete components are anticipated as most components can be formed in semi- conductive layers, if necessary using the full area of the display. By means of a the multi-layer approach, reflective multi-stable/bi-stable LED with a functional layer described above, the display is converted from a display technology into a fully functioning out-of-the-box product made from layers and substrates which is further enhanced by being compatible with roll-to-roll or reel-to-reel or web manufacturing technology.

These functions make use of the large area that the display naturally encompasses, thereby minimising the need for specialised electronic circuitry.

As a further benefit, the display will be roll able and package able, fitting easily onto existing locations and requiring no special skills for installation.

As a further benefit, wireless communication to the display means that certain government bodies may be able to override existing messages to inform the citizen of a civil emergency, for example.

As a further benefit, the components being built into the layers of the flexible display, it will be impossible for a person wishing to access the screen for 'hijacking purposes' to access the necessary circuitry. This is unlike existing displays where the required display connectivity is usually accessible, typically allowing groups to 'hack' the advertising site.

As a further benefit, the excess power generated by a large area of photovoltaic film can be used to provide a source of locally-derived renewable energy.

Waste disposal of the screen is easier with the multilayer approach because it uses minimal materials and needs no special separation before waste processing.

Operation of reflective bi-stable LED devices and arrays is well-known. An example of such devices is provided in European patent application number 07733096.7 and others. One of the advantages of such devices as described above is that energy is only required upon switching between the stable states so typically on and off with a polarizing layer acting as a filter. Thus, such devices are low energy consumers and use nascent natural light reflection for back illumination. In such situations with signage it is possible to provide even more control if switching is limited to when power is available e.g. solar generated power so although limiting switching at will may be every 30 seconds switching periods can be lengthened, or shortened, if power consumption is not sustainable by generation e.g. to 45 seconds if there is less sunlight. Such an approach and other functional aspects require control circuitry and methodology but provision of separate control boxes and external requirements will limit application particularly in low cost and ready to use out of the box applications. The price of reflective bi-stable and multi-stable LCD arrays and displays can approach that of or not much more than paper or card or plastic sheet panels but the ancillary equipment and skilled installation requirements will limit application as simple information displays and the like. The tendency is to provide a dedicated infrastructure of control and power supply arrangements to which the reflective bi-stable LED array can be associated.

Aspect of the present invention relate to providing as much as possible a stand-alone and independent electronic display in a flat format which is flexible and has as simple a set up procedure as possible which is ideally Out of the box and go' with may be a simple switch action or initial electrical charge bump start. The reflective bi-stable LED array is combined in layers with a functional layer or layers to provide a planar panel so that the whole can be manipulated into assembly as an electronic display. As described above the functional layer provides power and/or control for the LED array as required. The combination as an electronic display which is flexible to allow rolling for storage and/or transportation but once unrolled or otherwise manipulated to provide an electronic display by adhesion to a surface such as a wall or in a frame the electronic display is operable without any further actions by the installer other than operating a switch or providing an initial electrical charge before an in-built battery or solar power generator (PV elements) become operative to power the electronic display thereafter would be ideal.

Integration of the LED array and the functional layer provides a unitary action and independent operation. Integration can be by forming the whole combination of LED array and functional layer or layers by traditional deposition one upon the other for semiconductor devices or effectively making each layer separately then 'rolling' the layers together with alignment of connection areas as necessary but most importantly adhesion or fusion of the layers as a combination for co-manipulation as required in installation. The LED array and functional layer or layers will have a flexible substrate to allow flexibility and manipulation together so that the inter-layer bonding is not overly strained. Typically, there will be direct electrical connections between the layers for power and/or control functions but it will be understood indirect or wireless connection is possible by electrical inductive couplings and connections such as by BlueTooth if each layer has the necessary configuration. Figure 1 provides a schematic and exploded view of an electronic display 100 in accordance with aspects of the present invention in which a reflective multi-stable or bistable LCD array is in a layer A with a number of other functional layers such a battery layer B, a photovoltaic layer (PV) 10 to generate electrical power, a touch/proximity sensitive layer 20, a control circuitry layer 30, an antenna layer 40 and a colour filter/printed material layer 50. As indicated above the display can be made by semiconductor fabrication processes such as deposition or the layers A, B, 10, 20, 30, 40, 50 can be combined by a rolling process where they are forced together to fuse and integrate. The order and stacking of the layers and the LCD array is such that one on top of the other in stacks there is limited or control or enhanced interference between the functions of the layers so for example the multi-stable LCD states may be used to steer and shutter light for back reflection as required as well as possibly to vary exposure of a PV panel for power generation.

The reflective multi-stable or bi-stable LCD layer comprises a liquid crystal layer or layers 1 with transparent containment substrates 2, 5 either side to retain liquid crystal in cavities or cells in the layer or layers 1. Electrode substrates 3, 6 are provided either side of the substrates 2, 5 so that electrical fields may exert influence on the liquid crystal in the cavities and cells to switch between stable states. These stable states are generally or normally out of phase by 45° so that with a reflective layer 4 and a polarizing layer 7 such a switch acts to provide reflected illumination in one state and no illumination in another state. With a multi-stable LCD array there can be conditions between effectively on = reflective and off= non-reflective conditions for the device as 'grey' states which may be used to avoid or limit or control or enhance functional layer operation or stable state operation in use. This illumination can be used to illuminate a colour or printed material layer 50 so that text or images are illuminated as required.

As indicated above multi-stable or bi-stable devices use little energy as power is only required upon switching but nevertheless a power source is required. In figure 1 a battery layer B is provided with anode and cathodes 201 , 202 respectively either side of an electrolyte layer 203. The layers 201 , 203, 202 act as a battery to provide electrical power to the electrodes 3, 6 for the LED array for switching or to other functional layers if required. The battery layer B can operate alone in some embodiments so giving the display 100 a finite life before replacement is required. However, more normally a power generating functional layer will be provided such as illustrated in figure 1 a PV layer 10 which can provide power directly to allow switching may be through an accumulator type device such as a capacitor or the power generating layer 10 may charge a battery such as the layer B to store the electrical power to switch the LCD array between the stable states.

As indicated out of box operation and independence are desirable so at the heart of the display 100 is a control layer 30 which may act with the battery layer B or PV layer 10 and input means such as a touch sensitive layer 20 to provide independently powered and self-contained control of the display 100. The control layer 30 is typically a printed circuit deposited or formed with electronic components such as processors etc. to control the function of the display such as which stable stage will be retained, the capability to switch stable states dependent upon electrical charge availability. As with previous layers the control or circuit layer 30 can be deposited or formed and rolled into integration. The display 100 may need to interact with passing PDA devices or other displays in the vicinity so an antenna layer 40 may be provided.

It will be understood that the orientation and order of stacking of the functional layers upon and about the reflective bi-stable LCD array may be important. It will be understood that that the power generation layer such as PV layer 10 will typically be maximized and so span most if not all of the width of the display 100. However, if the PV layer or part of it is obscured by other functional layers then the efficiency of the power generation function will be diminished. Generally the control layer 30 with its electronic components will be the most obscuring layer so the orientation will be such that side L will be the externally or light facing side whilst side R will be the rear side so that the PV layer 10 is exposed to the light along with the colour filter or printed matter layer 50 illuminated by back reflection from the reflective bi-stable LCD array layer A. Physically the correct orientation may be forced by the reflective layer or the functional layers only or differentially providing reflective illumination of the image information in the display in one orientation only.

It may be possible for some functional layers and possibly parts of the LCD layer A to have more than one function so for example the control layer 30 may incorporate a battery or capacitor to provide an electrical power source in its own right so that a dedicated functional layer to act as a battery may not be required within the stack of layers reducing display thickness.

The layers in the display 100 as indicated above will be consolidated by fusion or adhesion so that an integral panel is formed. The panel will be flexible due mainly to a plastic or flexible substrate for each of the layers. Alternatively, it will also be understood that, although less acceptable, it may be possible to provide a multitude of platelet or scaled elements effectively hinged along edges by a flexible layer for at least part of the depth of the display.

The layers in the display 100 will be relatively thin. Figure 1 is schematic and generally not in proportion. The display 100 will typically only have a depth of less than a millimeter at most so manipulation of the display will be similar to paper or card or plastic sheet. The layers will be associated such that bending does not unduly stress the layer to layer bonding in manipulation for assembly into an actual electronic display or for storage or transportation. Clearly there may be a limit to bending and flat folding may be possible but normally significant bending will be allowable. Splitting, 'de-lamination and tearing between layers will inherently diminish and interfere with desired functional layer to layer performance and possibly neutrality between the LCD layer and the functional layer or layers.

Figures 2 to 4 provide illustrations of examples of a display in accordance with aspects of the present invention formed in to practical electronic displays. In figure 3 a display 200 is simply adhered to a wall 201. The display is shown as rectangular but it will be understood that other shapes are possible as the display 200 is not constrained by a frame. The display can be secured by an adhesive or fastener such as drawing pins or possibly by an electro-static effect upon the wall. For an adhesive fastening it will be understood that sections of adhesive pad may be exposed by removing tear off tags or covers. Paper posters typically use a peelable adhesive rear face and this may also be used with displays in accordance with aspects of the present invention. For drawing pins it will be understood there is danger of the pin or similar fastener piercing a vital part of a functional layer so normally an upper surface of the display will have indicators as to where pins can be inserted. For electrostatic adhesion care must be taken to ensure the static electricity does not interfere with the functional layer and/or the LCD array so electrical insulation will be required and possibly the electro-static effect limited to edge portions. In any event the display 200 can act as a white board or blackboard simply secured to a wall at will. Furthermore due to the multiple stability of the LCD array it will be possible simply to have a message illuminated when required or for example in a teaching environment to have different sections of the display illuminated at different times so section 200a may gave a question or a picture and section 200b an answer or answers which can be revealed by the teacher or by polling the students etc. to provide some interactive feedback. The display may simply be an information board with the battery having a fixed life and so the information board also having a fixed life for switching between the stable states so that the alteration draws users' attention. The fixed life may relate to a payment made so that at the end of the time period paid for then the battery does not provide power and the display remains in the state when the information is not reflectively illuminated. Alternatively at the end of the battery life the default may be to the reflective illumination state so the information will be illuminated but without the attractive blinking.

The example provided by figure 3 provides for a display 300 which may operate in a similar fashion to the display illustrated in figure 2 but the display 300 is retained in a frame 301. The frame constrains edges so that broken line 302 illustrates the edge of the display 300. In such circumstances alternately due to the more positive fixing of the display 300 thicker/heavier or thinner/lighter display panels may be accommodated. Furthermore by use of a frame it will be understood that greater security from theft or damage to the display may be achieved.

A desire with aspects of the present invention is that the display is self contained and easy to transport. As displays in accordance with aspects of the present invention are an integration of at least one functional layer and a multi-stable/bi-stable reflective LCD array so that there is flexibility and mutual manipulation it will be understood that rolling of the display as illustrated in figure 4 provides a convenient arrangement for storage and/or transportation. The degree of rolling in terms of curvature will be within the range acceptable for the degree of flexibility for the display which to a certain extent will be dependent upon the substrate materials. Ideally the roll will be of a similar size as comparable paper or card or plastic materials based signage. On deployment the display roll will be unrolled to a flat plane to act as a display. At this point the battery may become operative by a switch action (not shown) or separation of proximity contacts which are close when rolled or other means. In such circumstances the electronic display will become immediately activated. It will also be understood that the panel may have an electrical power generating layer so the panel may become active when there is a power flow from the PV panel or other functional layer for power generation or initially work from battery power then generated power or a bump initiation electrical power surge provided by contact at an appropriate position or by induction before on-going generated power operation.

Electronic displays in accordance with aspects of the present invention will tend to be relatively large such as billboards or notice boards. Such device are a sufficiently large to be seen at a distance so will tend to be tens of centimetres or more across. With a whole width PV layer as an electrical power generator and even though the conversion efficiency will be low it will be understood that with a bi-stable reflective LCD array it may be only a proportion of that power will be used so the excess power may be used for other purposes when available such as charging a battery for night time periods. However, within the confines of a desire for independence it may be possible to use the electrical power for other uses such a heater pad to evaporate a perfume or aroma impregnated into part of the display e.g. an advert for a food or drink may be enhanced with a scent or the electrical power may be used for burst communications with PDA devices when within the vicinity of the display e.g. issuing time limited promotional codes for a product or service. A large area for the PV generator layer will mean even if incidently light is obscured to part of the display still sufficiently electrical power will be generated in a stack or layer upon layer display configuration as described with regard to aspects of the present invention.

As indicated above it would be desirable if the costs of electronic displays in accordance with aspects of the present invention were low so that the displays are effectively disposable after use whilst being recyclable. In such circumstances, and the using of rolling processes, will allow a web of displays to be formed with separation of functional zones along the web as well as possibly across the web. The functional zones may be severable to form displays in their own right or a display in use may comprise a number of the functional zones each operable separately or in concert with other zones to provide a display. As indicated above such an approach may allow stiffer plates of functional zones formed by several layers of functional layers and an LCD array to be rendered more flexible to allow combined manipulation for assembly, storage and/or transport by the effective hinging between the functional zones by the over-arching or connector flexible substrate linking the functional zones which may be weakened to allow such flexing and if necessary severing.

An over layer which simply acts to demark zones of the display may be provided. The over-layer may be integral or printed upon the display or detachable when the function of indicating demarcation has been completed e.g. the right orientation for the display or keying the display with other displays in a mosaic of displays side-by-side to create a larger display image as seen by a viewer.

A display in accordance with aspects of the present invention may be provided as a print stock material for lithographic printing of an image overlay upon the display which can then be cut as required. Typically the display will be flat and smooth but it may be possible to provide displays in accordance with aspects of the present invention which have raised portions (bobbly) or have undulation or curves or a bias to such disposition so that locations which can be depressed for a response or interaction with display can be defined. Such shaping will be provided by the nature of the substrate material or its treatment.

Modifications and alteration to aspects of the present invention and in particular to the examples described will be appreciated by persons skilled in the technology. For example it will be appreciated that the functional layer may have apertures or holes matching parts of the reflective bi-stable LCD array or a PV electrical power generating layer so that the operation of the LCD or PV layer is not unduly impaired. The size and distribution of the apertures may vary across the display. In some circumstances it may be advantageous to have an indicator of display age so a layer or an over-layer of the display may have a photo-sensitive dye which darken or lightens with light exposure.

It will be appreciated by those skilled in the art that any number of combinations of the aforementioned features and/or those shown in the appended drawings provide clear advantages over the prior art and are therefore within the scope of the invention described herein.

Claims

1. An electronic display comprising a multi-stable reflective LCD array in an integral multi-layer stack with at least one functional layer to provide a control function for the LCD array, the functional layer in electrical connection and/or communication with the LCD array directly or wirelessly layer upon layer for compliant association for manipulation together for storage, transportation and assembly of the electronic display in use.

2. An electronic display as claimed in claim 1 wherein the multi-stable reflective LCD and functional layer are fused or adhered together whereby the manipulation includes rolling and/or folding.

3. An electronic display as claimed in claim 1 or claim 2 wherein the display to one side is configured whereby the manipulation includes association with presentation means such as a backing surface or a frame with or without an adhesive or other fastener.

4. An electronic display as claimed in any preceding claim wherein the electronic display is a billboard or signage or whiteboard or blackboard.

5. An electronic display as claimed in any preceding claim wherein the functional layer is one or more of the following:- a. An antenna receiver typically in a flat panel form.

b. Metallised substrates co-formed with an electrolytic-impregnated matrix to form a battery.

c. Metallised substrates configured to provide a capacitor and a sensor sensitive to approach of a person and/or a vehicle and/or movement.

d. A film configured to be touch sensitive.

e. Integrated and/or discrete electrical components to provide the control function.

f. An static electricity function for adhesion to wall or other surfaces.

g. A printed relief or luminescent information surface.

h. A thermoelectric cooling layer.

6. An electronic display as claimed in claim 5 where the functional layer is an antenna receiver and the antenna receiver is formed by at least part of a reflective surface of the bi-stable reflective LCD array.

7. An electronic display as claimed in claim 5 or claim 6 where the functional layer is an antenna receiver and the antenna receiver is part of a two-way transmitter receiver for communication with near field devices such as PDAs.

8. An electronic display as claimed in claim 7 wherein the two-way transmitter receiver is configured to provide encrypted communication such as with Bluetooth.

9. An electronic display as claimed in any of claims 5 to 8 wherein the functional layer is an antenna receiver and the antenna receiver is printed and/or etched to provide a secondary coil for inductive electrical charging.

10. An electronic display as claimed in any of claims 5 to 9 wherein the functional layer is an antenna receiver and the antenna receiver is configured to monitor background r.f radiation as a detector for vehicle approach.

1 1. An electronic display as claimed in claim 5 where the functional layer is an electrical component and the electrical component is printed.

12. An electronic display as claimed in claim 5 or claim 1 1 where the functional layer is an electrical component and the component is provided in semi-conductor layers.

13. An electronic display as claimed in claim 5 where the functional layer provides a static electricity function and the static electricity function is limited by configuration of the functional layer to portions of the display.

14. An electronic display as claimed in claim 13 wherein the portions are edge portions and/or spaced portions.

15. An electronic display as claimed in claim 13 or claim 14 wherein the portions are electrically isolated from the remainder of the display.

16. An electronic display as claimed in claim 5 where the functional layer is an information surface and part of the surface is removable from the remainder of the display.

17. An electronic display as claimed in any preceding claim wherein the display is associated with an external battery and/or accumulator and/or capacitor at least for initial activation.

18. An electronic display as claimed in any preceding claim wherein the display includes charging means for periodic charging of the display.

19. An electronic display as claimed in claim 18 wherein the charging means is inductive and/or by contact and/or by static electricity charging as the display is wiped for cleaning or otherwise.

20. An electronic display as claimed in any preceding claim wherein the functional layer may include a light sensor.

21. An electronic display as claimed in claim 20 wherein the light sensor is configured to determine incident light upon display whereby the control function can determine a level of electrical power generation.

22. An electronic display as claimed in any preceding claim wherein the control function is configured so that dependent upon the level of electrical power generation and/or other power source the control function determines which parts of the functional layer are functional.

23. An electronic display as claimed in any preceding claim wherein the control function is configured so that the control function provides and maintains a record of incident light and/or electrical power generation.

24. An electronic display as claimed in claim 23 wherein the control function is configured so that the record is used to determine a necessary electronic display configuration for a location for such electronic displays thereafter in terms of necessary battery capacity and/or potential electrical power consumption by the functional layer and/or future charging top-up of the electronic display and provide an indication of that determination.

25. An electronic display as claimed in any preceding claim wherein the LCD array and/or the functional layer are formed by layer upon layer deposition.

26. An electronic display as claimed in any preceding claim wherein the LCD array and the functional layer are configured in combination to have a substantially plastic nature.

27. An electronic display as claimed in any preceding claim wherein the functional layer has transparent windows overlapping the bi-stable reflective LCD array.

28. An electronic display as claimed in any preceding claim wherein the LCD array and the functional layer have a repeat pattern of functional zones substantially separable and operable from other functional zones.

29. An electronic display as claimed in claim 28 wherein the LCD array and the functional layer in each functional zone are co-dependent upon each other.

30. An electronic display as claimed in claim 28 or claim 29 wherein the display is severable about the functional zones.

31. An electronic display as claimed in any preceding claim wherein the display has an over-layer.

32. An electronic display as claimed in claim 31 wherein the over-layer is detachable as a protective cover.

33. An electronic display as claimed in claim 31 wherein the over-layer is integral with the display.

34. An electronic display as claimed in any of claims 31 to 33 wherein the over-layer demarks areas of the display.

35. An electronic display as claimed in claim 34 the areas demarked are for attachment of the display.

36. An electronic display as claimed in claim 34 the areas demarked are for designation of parts of the functional layer and/or the LCD array.

37. An electronic display as claimed in any of claims 31 to 36 wherein the over-layer is photo-sensitive to darken or lighten as an indication of light exposure age.

38. An electronic display as claimed in any preceding claim wherein the reflective LCD array is configured whereby one or more of the multi-stable states limits or avoids or facilitates operation of the functional layer or one of the functional layers

39. A method of manufacturing an electronic display as claimed in any preceding claim wherein the multi-stable LCD array and the at least one functional layer are rolled into integral association.

40. An electronic display as claimed in claim 5 where the functional layer is a thermoelectric cooling layer.

41. An electronic display as claimed in claim 40 wherein the thermoelectric cooling layer is a Peltier film or mesh or wire layer.

42. An electronic display as claimed in claim 40 wherein the thermoelectric cooling layer is a Seebeck cooling system.

43. An electronic display as claimed in claim 40 wherein the thermoelectric cooling layer is a Thomson cooling system.

44. An electronic display as claimed in any preceding claim further comprising a protective layer.

45. An electronic display as claimed in claim 44, wherein the protective layer is a heat protective layer.

46. An electronic display as claimed in claim 44, wherein the heat protective layer is a thermoelectric cooling layer.

47. An electronic display as claimed in claim 46 wherein the thermoelectric cooling layer is a Peltier film or mesh or wire layer.

48. An electronic display as claimed in claim 46 wherein the thermoelectric cooling layer is a Seebeck cooling system.

49. An electronic display as claimed in claim 46 wherein the thermoelectric cooling layer is a Thomson cooling system.

50. An electronic display as claimed in any preceding claim further comprising an antiglare portion.

51. An electronic display as claimed in claim 50, wherein the anti-glare portion is a polarising film.

52. An electronic display as claimed in claim 51 , wherein the polarising film is oriented horizontally with respect to the display.