IMPROVED OPTICAL ELEMENT WITH SANDWICHED COVER

Abstract

1 8 Optical element comprising a cover having a first surface and a second surface, a support, and a means. The cover is orientated with the first surface directed towards the support. A part of the first surface is attached to the support. A spatial arrangement of the cover as seen in a cross section of the cover defines a cover contour profile. The optical element further comprises a further means, wherein the means and the further means are placed on opposite sides of the cover, and the means and the further means are collectively arranged to move the cover between a first cover contour profile and a further cover contour profile which is different from the first cover contour profile.

Description

l IMPROVED OPTICALELEMENTWITHSANDWICHEDCOVER The current application relates to an optical element comprising, a cover having a rst surface and a second surface, a support, and ameans. The cover is orientated with the rst surface directed towards the support, a part ofthe rst surface is attached to the support, a spatial arrangement ofthe cover as seen in a cross section ofthe cover denes a cover contour prole, and the means is arranged to move the cover from a rst cover contour prole to a further cover contour prole which is different from the rst cover contour prole. An optical element is known from e.g.WO 2021 / 032752 Al andWO 2018 / 228671 Al. This document discloses optical devices ofspecic interest. The working principle is thatwhen a cover is provided that has some desired optical behaviour, e.g. reecting light, transmitting only some light, etc. the interaction ofincident light can be changed by changing the cover contour prole. To facilitate the cover changing shape to facilitate changing the optical behaviour ofthe optical device, the cover is made relatively thin, in terms ofWO 2021 / 032752 Al 2-dimensional. As an example, a single graphene layer cover is presented, with a coating on top to obtain desirable optical behaviour. Since the optical device is very small, they can be used to act like a pixel in a larger collection of similar devices. Control of scattering, reection and / or interference behaviour can be used to turn a pixel on or offand / or vary its colour. This way, images can be generated and / or manipulated. Several principles ofoperation are available with such optical devices.A rst operational principle is shown in gures lA lC, which correspond to gures 9 ll ofWO 2021 / 032752 Al. These gures show respectively an optical device with a at cover, a convex cover, and a concave cover. Light incident on the at cover (g. 1A) is reected as ifhitting a smooth and straight surface, i.e. parallel incident rays remain parallel after reection. As such, specular reection takes place at the cover. In the convex and concave positions ofthe cover, parallel incident rays are no longer parallel after reection, thus causing diffuse reection. By changing the shape ofthe cover, it is thus possible to alternate between specular and diffuse reection. To suit this rst operational principle, the cover is sufciently reective towards the incident light. In this example, the light is incident on the second surface, whichmay also be called the outside ofthe optical device. Figures 2A 2C, which correspond to gures 12 l4ofWO 2021 / 032752 Al, show a second operational principle. Reference is rst made to the substrate which spans the support on an opposite side ofthe cover, in order to dene a cavity between the cover and the substrate. The substrate is partly reective and partly transmissive. The cover is relatively reecting. Light incident on the substrate is thus partly transmitted and partly reected. The transmitted light reects on the rst surface ofthe cover, i.e. coming from the inside, and is transmitted back through the substrate, where it interferes with the light reected by the substrate. Depending on the wavelength ofthe light and the distance between the cover and the substrate, the interaction can be constructive or destructive. Since that distance changes when the cover changes shape, the interferometric characteristics ofthe optical device can be changed. Figures 6 and 7 show even otherways ofusing the changing cover contour prole. In the case ofgure 6, an optical element is shown with a substrate 106 that is relatively reective. The cover 101 in this case is relatively absorbing. Nevertheless, ofan incoming lightbeam 601, at least some lightmay be transmitted towards the substrate 106 as transmitted lightbeam 603. This reects back via the substrate 106 as reected light 604. Due to interference ofthe transmitted lightbeam 603 and the reected light 604, a pattern ofnodes and antinodes is present. The cover 101 can then be moved, e.g. by changing its cover contour prole or its position with respect to the support, to place the cover at an antinode for absorbing the light, or at a node for not or absorbing less the light. Accordingly, the exiting light 605 can be present in less ormore intensity by controlling the cover. This principle is called interferometric absorption. Figure 7 shows the principle ofinterferometric reection, similar to g. 2, but with light 601 incident the cover. In this case, light is partially transmitted through the cover 101, and reected at the substrate 604, which for that purpose is reective. The cover 101 reects some light 605, but also transmits some light 603. After reecting 604 from the substrate 106, light passing through the cover 101 again interferes with the reected light 605. By controlling the position or cover contourprole ofthe cover 101, control is possible ofwavelengths oflight that do or do not interfere constructively. In both cases, light transmitted through the covermay actually be refracted. However, since the gures show a specic example oflight incident normal to the cover, the wording transmitting was used. The invention can however be applied, depending on the use-case, to non- normal light also. These principles have been described only briey herein, as the operational principles involved are in themselves known, and have been applied e.g. inWO 2018 / 228671 A1 (see gures 1 and 2). These principles thus show thatby varying the reectance and / or transmittance and / or absorbance ofthe cover and the substrate, and the direction atwhich light is incident (from outside or inside the optical device), it is possible to cause the cover to create a certain interaction with the light, optionally in cooperation with the substrate. The interaction changes when the cover shape changes, i.e. when the cover contourprole changes. The mechanics and dynamics ofthe optical element presented inWO 2021 / 032752 A1 are fundamentally directional. The realization that at least partially removing this directional behaviourmay increase the versatility ofthe optical element is the basis forthe current invention. The invention has as its object to provide amore versatile optical element. The identied directionality means that the optical element behaves differently as seen in one direction (e.g. pointing from the rst to the second surface ofthe cover) than in another (e.g. pointing from the second to the rst surface ofthe cover). This difference is caused by the fact that the means are arranged on a single side ofthe cover. One limitation optical elements such as the ones discussed hereabove may have is the fact that their covers can only be moved into one direction as seen from their base position, depending on the type ofmeans that drive them. This stems from the fact that the means are only located on one side oftheir surface, and can only pull the covertowards it. This limits the proles and cover shapes that can be achieved, and in turn limits the versatility regarding e.g. colours or light intensity the optical element can accomplish. It is an object ofthe invention to at least partially address this problem. More specically, it is an object ofthe invention to provide an optical element that can be moved in multiple, opposing directions as seen from its initial position, such as for example both upwards as well as downwards. The object is achieved by an optical element according to the preamble, wherein the optical element further comprises one further support and one furthermeans, wherein the means and the furthermeans are placed on opposite sides ofthe cover, and the support and the further support are placed on opposite sides ofthe cover, and the furthermeans is adapted and arranged to move the cover from the rst cover contour prole to a third cover contour prole, wherein the second and the third cover contour proles are different. According to the invention, it is possible to exert more control over the cover, since the means and furthermeans cannow be used collectively to urge the cover to a further contour prole. The means may be made to cooperate with each other in various ways, as will be explained further below. First however, it is noted that it is particularly advantageous ifthe means and / or the further means are transparent. Transparentmay herein be dened as transparent for the relevant wavelengths forwhich the device is used. In practice, the means may be transparent for visible light, UV, EUV, infrared orTHz radiation. As the means are on both sides ofthe cover, they will effectively sandwich it. In order for the optical element, and e.g. any display it is part of, to function correctly, it is necessary for light to be able to escape. Therefore, using transparent means and / or furthermeans can aid in allowing light to reach out ofthe optical element. It is noted that for some applications, using a translucent means might be sufcient as opposed to a fully or partially transparent version. Furthermore, transparent herein is used to describe transparent to relevant wavelengths, whichmay be any one or more ofthe following: visible light, ultraviolet, extreme ultraviolet, infrared, or terahertz wavelengths, or other some otherpredened radiation spectrum. It is especially advantageous ifthe means and the furthermeans are arranged to generate opposite forces on the cover. In this manner, the arrangement ofthe means and furthermeans can be used to apply forces in opposing directions to the cover even with means suited for creating uni- directional forces. As an example, two means that can by themselves only attract the covertowards themselves, can with the claimed conguration be used to move the cover back and forth under their force. Accordingly, one way ofgenerating such opposite forces can be ifthe means and the furthermeans are arranged to generate an attracting force on the cover. As they are located on opposite sides ofthe cover, this attracting force will be in opposite directions, thus allowing for the desired movement in multiple directions. Ofcourse repelling forces can be used instead. Even when means are applied that are capable ofproviding both attracting and repelling forces it is possible to use means and furthermeans that are arranged to generate opposite forces, since in this case the means and furthermeans may be used to interfere either constructively or destructively, at will. In this case, but also in others, it is advantageous for the means and the furthermeans to be individually controllable. This way, the shape andmovement ofthe cover can be controlled even more precisely, and it is possible to for instance choose between varying degrees ofconstructive or destructive interference. Force elds can therefore be generated that could not otherwise be generated. In particular, a force eld with a localmaximum orminimum can be generated, for instance in order to increase stability. In one embodiment ofthe invention, the means and the furthermeans each comprise at least one electric component, such as an electrode. This electric component can act as a supplier of voltage in the case ofan electrically driven means and / or further means, but can also aid in the controlling ofother types of (further) means. In case the component is an electrode, it can be used to create an electric eld to which the cover is responsive, e.g. by charging the cover. Ofcourse other operational principles for the means and / or furthermeans are possible, for instance pressure based or thermal based. These principles may be combined with each other and the electric activation as desired. In particular, the means and / or furthermeans may each, independent from one another, comprise any one ormore of: - an optical actuator, such as an optical tweezer or photonic circuitry, - ameans for applying or changing radiation incident on the cover, such as a radiation source. - ameans for inuencing a gas pressure acting on the cover, - a speaker or any other sound emitter, - a thermal actuator, operating viathermal expansion, and - an electromagnetic and / or superconducting actuator, for instance operating based on tunneling or eld emission. At this time, it is noted that regardless ofthe actuation method used, given a sufciently small system, any one actuation method will often have some corresponding co-phenomenon in another domain as well. As such, at nano-scale, the actuation method and corresponding co- phenomena usually pair up. Examples ofsuch pairs, whichmay be used in the currently described invention as a non-exclusive list ofexamples, are: - Thermo-electrical and electro-thermal actuation, - Thermo-optical and opto-thermal actuation, - Thermo-magnetic and magneto-thermal actuation, - Opto-electrical and electro-optic actuation, and - Magneto-optic and opto-magnetic actuation. At the same time, quantum and superconducting effectsmay also play a role. Accordingly, use can be made ofsuch effects ifdesired. It can be advantageous ifthe means and the furthermeans are identical in type, preferably identical. That is to say bothmay be pressure driven, both thermally driven, both electrically driven, or any type ofdrive support that an application could require, or a combination thereofthat is the same for the means and the further means. Having identical means and furthermeans could reduce costs and complexity ofthe system, and make control systems relatively elegant. When the means and submeans are identical, a highly symmetric elementmay be obtained, thatmay be largely direction agnostic, e.g. it behaves or can be controlled similarly in both directions. On the other hand, it is also possible for the means and the furthermeans to be ofdifferent types. This could for example be a pressure driven means and an electrically driven further means, or agas driven means and a thermal driven further means. This could allow for amore versatile system, which can be adapted to the exact needs ofa nal product the optical elements would be used in. In one embodiment ofthe invention, the optical element comprises a further support on a side ofthe cover opposite the support, wherein a part ofthe second surface ofthe cover is attached to the further support. The further supportmay offer further structural benets for the element. The further supportmay also aid in designing a symmetric element. In yet another embodiment ofthe invention, the optical element further includes a substrate on a side ofthe support opposite the cover. This embodiment can also optionally comprise a further substrate opposite the substrate. The substrate and / or further substrate may comprise or contain, or otherwise accommodate the means or furthermeans respectively. The substrate and / or further substrate can accordingly be used to provide further structural benets for the element. Additionally or alternatively, the further substrate and substrate may be laid out so that the element is symmetrical. The symmetrymay be ofthe plane symmetric type, with the cover as plane ofsymmetry.A symmetric optical elementmay be particularly versatile, and additionally or alternatively allow enhanced control ofthe cover, in particular its shape. The cover, support and substrate can together dene a cavity. Additionally or alternatively, the cover, further support and further substrate can form a further cavity. In the paragraphs hereafter, cavity can be used to refer to the cavity and / or the further cavity interchangeably. The cavity can be used for instance to provide interferometric capacity to the optical element. Furthermore, the index ofrefraction of said cavity can be ofinuence on the optical behaviour ofthe optical element. The index ofrefraction ofthe cavity can be inuenced by at least partially lling the cavity. To facilitate said lling the cavity may be enclosed by one ormore of the support, the cover and the substrate, ormay even be sealed entirely. Different llings ofthe cavity can lead to different refractive indices, and thus a different optical behaviour. The cavity may for this purpose be lled with agas composition. Aside from a gas or gas mixture, the cavity may also be lled by a liquid (mixture) and / or liquid crystals, or even a solid lling, whichmay have a greater effect on the refractive index. Another option would be to instill avacuum inside of the cavity. Denition of, and lling ofthe cavity may also be done for other reasons than inuencing the index ofreection, i.e. to provide absorption, to provide structure rigidity, or other reasons. The llings ofthe cavity and the further cavity can, but do not necessarily have to be, the same. On the other hand, the llings can also be different. Moreover, the substance lling a cavity can be ofinuence on other than the optical behaviour ofthe optical element, including but not limited to the mechanical response ofthe cover and the electrical inuence ofthe means.A lled cavity can also be used to exert a pressure on the cover, in order to move it using pressure based means. The invention also relates to amethod ofoperating an optical element as described in any ofthe embodiments hereabove, comprising operating the means and the furthermeans at the same time or altematingly. Due to said control, more complex shapes may be imposed on the cover, and / or its shape may be adapted more quickly, thus resulting in specic visual output or achieving a higher framerate. Further advantages may be obtained alternatively or additionally. It is possible to control the means and the furthermeans differently, i.e. operating them differently, e.g. to different degrees, or less strongly than one another. This may allow for an even wider variety ofresulting cover shapes, or dynamics. As a result, the optical element becomes more versatile. The optical element described herein can be ofany suitable type, and provide optical behaviour based on any number of suitable principles. As an example, the optical device can operate by reecting light using the cover. For that purpose, it is possible the cover has a relatively large reectance as compared to its transmittance. As an example, the value oftransmittance divided by reectance would be not more than 0.5, preferably notmore than 0.25, more preferably notmore than 0.1, most preferably not more than 0.01. The transmittance, reectance and absorbance dened herein may be measured at a wavelength X which varies from 10nm to 3000 um. In one aspect, most preferably 380 to 740 nm. In another aspect, more preferably from 10nm to 200 nm, most preferably from 13 nm to 193 nm. In another aspect, more preferably from 700nm to 2000 nm, most preferably from 850nm to 1550 nm. In another aspect, more preferably from 30 000nm to 3 000 000 nm. Ofcourse, absorptionmay also be considered. As an example, the optical device can operate by absorbing light using the cover. For that purpose, it is possible the cover has a relatively large absorbance as compared to its reectance. As an example, the value ofreectance divided by absorbance would be notmore than 0.5, preferably notmore than 0.25, more preferably notmore than 0.1, most preferably notmore than 0.01. The absorbance and reectance dened above may be measured at a wavelength X which varies from 10nm to 3000 um. In one aspect, most preferably 380 to 740 nm. In another aspect, more preferably from 10nm to 200 nm, most preferably from 13 nm to 193 nm. In another aspect, more preferably from 700nm to 2000 nm, most preferably from 850nm to 1550 nm. In another aspect, more preferably from 30 000nm to 3 000 000 nm. The optical elementmay be congured for reecting light incident on the second surface. In that case, the transmittance and reectance may be measured for light incident the second surface. Alternatively, the optical elementmay be congured for reecting light incident on the rst surface, in that case, the transmittance and reectance may be measured for light incident the rst surface. Besides using the cover for reection only or mainly, it is also possible to employ reective interference, taking place mainly between a reected lightbeam at the substrate (or cover) and a refracted lightbeam through the substrate (or the cover) that the cover (or substrate) reects, or absorbing interference, taking place mainly between a reected light bean with the incident lightbeam at the substrate (or cover) and its absorption at the cover (or substrate). An optical element congured for this purpose is called an interferometric optical device. The absorbance ofthe covermay accordingly also be relevant, as explained above. The interference may take place for light incident the second surface, or for light incident the rst surface. In the latter case, a substrate is needed below the cover, as is described further below. The substrate is congured for transmitting a part ofthe light and reecting a part ofthe light. The transmitted light is then reected on the cover, and transmitted back outthrough the surface. The egressing light interferes (constructively or destructively) with the directly reected light. Depending on the position ofthe cover with respect to the substrate, it is possible to change the interference-based behaviour ofthe optical element. Depending on the desired optical behaviour, it is ofcourse possible to use a cover with different ratios ofreectance, transmittance and absorbance, optionally in combination with e.g. a reective, transmissive or absorbing substrate, the terms reective, transmissive or absorbing being dened using the same ranges for these respective quantities, and / or the same ratios between them as is dened for the cover. In general, the optical properties for the substrate are chosen complimentary to the optical properties ofthe cover. The invention is not limited to any such combination, rather to improving movement ofthe cover using the sandwiched cover. Ofcourse, the substrate need not be square or rectangular. The substrates shape in general is not important, it is even possible for a single substrate to span multiple optical elements. More relevantmay be the shape dened within the support, as this denes the shape ofthe optical element in plan view. It is possible this shape is square or rectangular, to create a pixel-like element, but circular optical elements are also envisaged. The invention may however be applied to optical elements ofall shapes. This is true for all embodiments described herein, whether they do or do not have a substrate. It is noted that for some shapes ofoptical elements, the substrate is rigid and planar, while for others it is possible for it to be exible and / or curved. In such cases, the spacer and cover are adapted to the substrate, in such away that the second surface ofthe cover is approximately parallel to the substrate. In this case, the cover is preferably reective, for instance as expressed in the ratio above. The substrate is not as reective, for example having a ratio oftransmittance divided by reectance ofmore than 0.5, more than 0.75, more than 0.9 or even more than 0.99, or even more than 1, preferably for light incident from a surface ofthe substrate facing away from cover. The opposite direction is also possible, where the cover transmits and reects light, and the substrate reects the transmitted light. In this case, the coverwould be relatively transmissive, for example having a ratio oftransmittance divided by reectance ofmore than 1, for light incident the second surface, so that it is relatively transmissive. Said ratio could for instance be between 1 and 3, such as between 1.5 and 2.5, such as around 2. The absorbance could in this case be relatively high. The substrate would preferably be reective for light incident a surface ofthe substrate facing the cover. The reectance could be dened by a ratio oftransmittance divided by reectance ofnotmore than 0.5, preferably notmore than 0.25, more preferably notmore than 0.1, most preferably notmore than 0.01. Unless stated otherwise, transmittance and reectance are measured for light normal to the surface ofthe cover. In case a cover is used that is relatively reective, a value ofabsorbance divided by reectance ofthe cover can be less than 0.5, preferably notmore than 0.25, more preferably not more than 0.1, most preferably notmore than 0.01, for light incident the rst and / or second surface, depending on the desired optical behaviour. It is noted that in all cases, the position and shape ofthe cover inuences how the optical device interacts with incident light. Other operational principles which rely on the change ofthe cover position and shape can however also be applied, and the current invention is thus not limited to either reective or interferometric operational principles. In any case, the invention is not limited solely to a cover with a changing shape or a changing cover. In terms ofclaim 1, this can be realized by dening the spatial arrangement ofthe cover with respect to the support. After all, a cover that has not changed in shape but is at a different position with respect to the support, still has a different spatial arrangement as seen in cross section ofthe coverwith respect to the support. As such, depending on the use, changing the position ofthe cover (without changing its shape) or changing the shape ofthe cover, thereby changing partially its position, could be used interchangeably. The covermay comprise a 2-dimensional portion. The 2-dimensional portion may be an extreme membrane. For the purpose ofthe invention in general however, it is sufcient ifthe 2- dimensional portion is sufciently thin to be deformed and / ormoved using the applicable means. In general, it is not necessary, however possible, that the 2-dimensional portion has favourable optical properties in and of itself. Instead, it is possible to provide the desired optical properties using additional material, such as an additional layer or an amorphous portion ofthe cover, which could be or could comprise a metal or an additive. In that regard, reference is made toWO 2021 / 032752 A1 which explains multiple congurations ofthe cover. The skilled person is readily able to vary e.g. the thickness and material ofthe additional material to arrive at desired optical properties for the cover. In that regard, it is noted the 2-dimensional portionmay function as a carrier, whereas the additional material provides desired optical properties. The 2-dimensional portion may be as dened in embodiment [39a] ofWO 2021 / 032752 A1. Accordingly, the 2-dimensional portion may be one ormore ofthe following: a. One ormore selected from the group consisting of: C, BN, P, MoS2, MoSe2, MoTe2, WS2, WSe2, WTe2, NbS2, NbSe2, NbTe2, TaS2, TaSe2, TaTe2, TiSe2, VSe2, CrS2, CrSe2, B, Ge, Si, Si2BN, Sn, Pb, P, Sb, Bi. The preferred C in this context is one ormore selected from the group consisting of: graphene, one ormore graphitic layers and graphyne, preferably graphene. The preferredBN in this context is h-BN. The preferred P in this context is black phosphorus or phosphorene. The preferred B in this context is borophene. The preferred Ge in this context is germanene. The preferred Si in this context is silicene. The preferred Sn in this context is stanene. The preferred Pb in this context is plumbene. The preferred Sb in this context is antimonene. The preferred Bi in this context is bismuthine, b. One ormore transition metal chalcogenides, each being a transition metal chalcogenide not listed in a., c. One ormore oxides, each being an oxide ofa species listed in a. or b., d. One ormore atomic intercalated variants, each being an atomic intercalated variant ofa species listed in a. or b., e. One ormore physically, chemically, mechanically and / or electromagnetically functionalised derivatives, each being a chemically functionalised derivative ofa species listed in a. or b..A preferred physical functionalisation is perforation or atomic barrage treatment.A preferred mechanical functionalisation is stretching or stressing.A preferred electromagnetic functionalisation is application ofa voltage. In one aspect ofthis embodiment, the 2-dimensional portion is a combination selected from the group consisting of: a., b., c., d., e., a.+b., a.+c., a.+d., a.+e., b.+c., b.+d., b.+e., c.+d., c.+e., d.+e., a.+b.+c., a.+b.+d., a.+b.+e., a.+c.+d., a.+c.+e., a.+d.+e., b.+c.+d., b.+c.+e., b.+d.+e., c.+d.+e., b.+c.+d.+e., a.+c.+d.+e., a.+b.+d.+e., a.+b.+c.+e., a.+b.+c.+d. and a.+b.+c.+d.+e.. Specically, the 2-dimensional portionmay comprise orbe graphene or boron nitride or both.A preferred boron nitride is hexagonal boron nitride. Graphene is preferably chemical vapour deposited. Boron nitride is preferably chemical vapour deposited. In one aspect ofthis embodiment, the 2-dimensional portion comprises graphene, preferably is graphene. In one aspect ofthis embodiment, the 2-dimensional portion comprises boron nitride, preferably is boron nitride. As mentioned earlier, the thickness ofthe 2-dimensional portion is relatively small. For instance, 1 mm or less, preferably 10 um or less, more preferably 1000nm or less, more preferably 100nm or less, more preferably 50nm or less. In one aspect ofthis embodiment, more preferably 10nm or less, more preferably 5 nm or less, most preferably 1 nm or less. A minimum thickness may be dened as 25 pm or more, preferably 69pm or more, more preferably 100pm or more. In one aspect ofthis embodiment, the thickness is 1 nm or more, preferably 3 nm or more, more preferably 5 nm ormore, more preferably still 10nm or more. In another aspect ofthis embodiment, the thickness is 15 nm or more, preferably 20nm or more, more preferably 30nm or more. Accordingly, the 2-dimensional portionmay be relatively light per unit area, such as 24 kg / m2 or less, preferably 2.4-10l kg / m2 or less, more preferably 2.4-102 kg / m2 or less, more preferably 2.4- 103 kg / m2 or less, most preferably 1.2-103 kg / m2 or less.A lower limit on the same weight per unit area is 1.7-109 kg / m2 or more, preferably 3.4-108 kg / m2 ormore, more preferably 1.8-107 kg / m2 or more. In one aspect ofthis embodiment, the mean density is 5- 107 kg / m2 or more, preferably 1.5-106 kg / m2 or more, more preferably 5.4-106 kg / m2 or more, more preferably 5.7-105 kg / m2 ormore. While above an optical element has been described that has means congured to affect the cover, the inverse is also possible and envisaged. Accordingly, the means may altematively or additionally be arranged to provide an output that is representative ofthe cover changing from the rst cover contour prole to the further cover contour prole. In this manner, the optical element can be used as a sensor responsive to any phenomenon, not necessarily optical, that changes the cover shape. For instance, incident radiation, pressure, sound waves, an electrical charge, temperature, etc. could all be sensed using suitable means. As an example, an electrode could be used to sense a changing electrical charge, e.g. changing in response to a charged cover moving. Ifa predetermined and externally applied electrical charge is applied to the cover, the electrodes could be used to measure deformation ofthe coverby capacitive means, for instance as a result ofincoming radiation or pressure. An electrode or other type ofsensing means would be necessary to measure the changing electric eld as the charged covermoves. In these circumstances, the element described herein need not be described as an optical element per se. As a further remark, it is noted that the structure described herein as optical element can be used in a different and novel way as well, regardless ofwhether or not the characterizing portion of the claims is applied. In this novel way ofusing the device, a substrate opposite the cover is necessary, so that a cavity is formed between the cover and the substrate. The device is congured to allow entry ofelectromagnetic radiation, such as (visible) light, into the cavity between the support and the substrate, and to allow egress ofthe same, also between the support and the substrate. In contrast to the principles shown above, in which light interacts by being incident the cover (either from the rst or second surface), the lightnow travels substantially parallel to the cover, through the cavity. In this case, the cavity acts like a waveguide. To form a waveguide, the skilled person is able to choose suitable materials for the support, the substrate and the material at the covers rst surface and optionally for material to ll the cavity with, so that the light is inuenced by the cover. This inuence could for example result in a change in amplitude, phase or the state ofthe light. Suitably chosen characteristics, such as optical characteristics, ofthe cover allow interaction with light passing through the cavity. By changing the contour shape ofthe cover, orby changing its position, the waveguide formed in the cavity can be altered. The changing inuence ofthe cover on waves passing through can be used to modulate the light. It is noted that the cover need not actually move or change shape in order to affect the passing light differently. For instance, its strainmay be altered for instilling different optical properties. The invention will be further elucidated with reference to the attached drawings, in which: Figures 1A, 1B and 1C show schematically interaction oflight with an optical element known in the state ofthe art, Figures 2A, 2B and 2C show schematically interference interaction oflight with an optical elementknown in the state ofthe art, Figures 3A, 3B, 3C and 3D show schematically examples ofdifferent cover shapes achieved by the invention, Figure 4 shows schematically an optical element comprising multiple controllers connected to the means and further means, Figure 5 shows schematically an optical element that is plane symmetric with the cover as plane ofsymmetry, Figures 6 and 7 show schematically an optical element for different interferometric effects, and Figure 8 shows schematically in perspective view anotherway ofusing the optical element. Figure 1A shows interaction oflight with ofa at cover 101, which is supported by supports 104. The parallel rays 601 and 602 are both deected by the same angle and remain parallel after interaction with the cover 101. This constitutes specular reection. Figure 1B shows interaction oflight with a convex cover. Due to the rounded convex cover contour prole, a rst ray 601 is deected by almost 180° and the second ray 602 is only deected by a small angle. The rays 601 and 602 are no longer parallel after reection at the cover. This constitutes diffuse reection. Figure 1C shows interaction oflight with a concave cover. Due to the rounded concave cover contour prole, a rst ray 601 is deected by an angle less than 90° and the second ray 602 is deected by almost 180°. The rays 601 and 602 are no longer parallel after reection at the cover. This constitutes diffuse reection. Figure 2A shows interference interaction with a at cover. Aside from the supports 104, a substrate 106 is also present in this example ofthe state ofthe art, which lies on the bottom ofthe optical element. The support 104, cover 101 and substrate 106 dene a cavity having a depth 205. The substrate 106 is transmissive and absorbing to an extent and the cover 101 is reective, such that an incoming ray 601 undergoes interference which is dependent on the depth 205. Figure 2B shows interference interaction with a convex cover. The cover 101 ofthe optical element ofgure 12 has been deformed into a convex shape (cover contour prole). This was brought about by ameans pushing the cover 101 upwards. This increases the depth 205 and the interference behaviour ofincoming light 601 is altered. Figure 2C shows interference interaction with a concave cover. The cover 101 ofthe optical element ofgure 12 has been deformed into a concave shape (cover contour prole). This was brought aboutby the means pushing the cover 101 downwards. This decreases the depth 205 and the interference behaviour ofincoming light 601 is altered. Now rst referring to gures 6 and 7, it is noted that depending on the optical properties of the cover 101 and the substrate 106, different operational principles are also usable for inuencing incident light. Figure 6 for instance, shows an optical element similar to that ofgures 1 and 2, but with a cover 101 that is relatively absorbing, and a substrate 106 that that is relatively reective. As a result, incident light 601 transmitted 602 through the cover 101 interacts with light reected 604 from the substrate to form a pattern ofnodes and antinodes. The cover can be controlled by means (not shown) to be placed at or away from a node or antinode, to accordingly absorb strongly or less strongly light, so that the intensity ofexiting light 605 can be controlled. In gure 7 a cover 101 is present that is both transmissive and reective, and a substrate that is reective. Accordingly, use can be made ofinterferometric reection, similar to gures 2A 2C, however now the optical element is congured for light incident the cover 101. Otherwise, the optical elementmay be identical to that described above. Figure 3A 3D show an element 99, with a cover 1, a support 4 and means 7. The cover is orientated with a rst surface thereofdirected towards the support, and a part ofthat surface is attached to the support.A spatial arrangement ofthe cover 1 as seen in a cross section ofthe cover denes a cover contour prole. Furthermeans 8 are provided, on an opposite side ofthe cover 1 as the means 7 introduced earlier. Collectively, the means 7 and furthermeans 8 are arranged to move the cover 1 between a rst cover contour prole and a further cover contour prole which is different from the rst cover contour prole. In the example shown, the means could be both electrodes that are controlled by a controller 12. The controller 12 is able to apply voltages to the means 7 and furthermeans 8 as desired. Ofcourse, means 7, 8 ofother types could be used. Figure 3A shows the cover 1 being substantially at, a situation that could be the neutral or inactivated shape ofthe cover. This neutral shape ofthe cover can be achievedwhen both the means 7 and the furthermeans 8 are inactive, orwhen both are activated in an equal manner, i.e. for a same duration, same charge, same pressure, etc. Figures 3B 3D show the cover 1 attaining different shapes, i.e. exhibiting different cover contour proles, depending on the activation ofthe means 7 and 8. For instance, in gure 3B, the means 7 could be electrodes, whereas the furthermeans 8 provide a gas pressure on the cover. The gas pressure exerted by the furthermeans 8 may push the cover 1 to curve downwards, whilst the means 7 exert amore focused and local upwards force. This could be achieved ifthe cover is charged similarly to the electrode. Figures 3C and 3D show the means 7 and furthermeans 8 cooperating to pull and / orpush the cover 1 in the same direction, thereby allowing the cover 1 to move both directions. Ofcourse, and as is shown in gure 4, the means 7 and the furthermeans 8 are each connected to an individual controller 12. Thismay facilitate construction, and / or individual control. Figure 5 shows yet another different example ofan embodiment ofthe invention. Aside from only having a support 4 on the side ofthe means 7, a further support 16 is present on the side ofthe furthermeans 8. Furthermore, a substrate 6 and a further substrate 17 are present on the side ofthe means 7 and furthermeans 8, and accommodate them, respectively. As a result, the optical element is plane symmetric with the cover 1 as plane ofsymmetry. Note that while the further substrate 17 and the further support 16 are exemplied in the embodiment with separate controllers 12 and grounds, these could also be present in the embodiment containing only a single controller 12 and ground forboth the means and the further means. Ofcourse, any othertype ofmeans 7, 8 could also be used as has been explained above. Finally, reference is made to gure 8, which shows a perspective view ofa device, such as an optical element, similar to that described herein. Like before, the device has a substrate 106 and support 104, which in this case are monolithic. The support 104 denes a cavity C that is of longitudinal shape in this example. Cover 101 held by the support 104 spans the cavity C. Materials for the support 104, the substrate 106, the material at the covers rst surface and material with which the cavity C is lled are chosen so that the cavity C acts as a waveguide. Incidentwaves 601, such as light, can therefore pass through from one side to another, and egress as exited light 602. Viameans 107, in this case presented on top ofthe support 104, although not strictly necessary, the cover 101 can be moved, or its cover contour prole changed. As a result, the cover 101 at least locally inuences the light passing through the cavity C in order to modulate it. It is noted thatterms like preferably, generally and typically are not utilized herein to limit the scope ofthe claims or to imply that certain features are critical, essential, or even important to the structure or function ofthe claims. Rather, these terms are merely intended to highlight alternative or additional features thatmay ormay not be utilized in a particular embodiment ofthe present disclosure. Likewise, for the purposes ofdescribing and dening the present disclosure, it is noted that the terms substantially and approximately and their variants are utilized herein to represent the inherent degree ofuncertainty thatmay be attributed to any quantitative comparison, value, measurement or other representation, as well as to represent the degree by which a quantitative representationmay vary without resulting in a change in the basic function ofthe subject matter at issue. While certain representative embodiments and details have been shown forpurposes of illustrating the present disclosure, it will be apparent to those skilled in the art that various changes may be made without departing from the scope ofthe disclosure, which is dened in the appended claims.

Claims

1. Optical element comprising: a. a covering with a first surface and a second surface, b. a support, and c. a means, whereby: - the cover is oriented with the first surface facing the support; - a part of the first surface is attached to the support, - a spatial arrangement of the deck considered in a cross-section of the cover defines a cover contour profile, with the characteristic that the optical element further comprises a further medium, where the medium and the further are placed by means on opposite sides of the cover, and The means and the further means collectively are configured to move the cover from an initial cover contour profile to a further cover contour profile that differs of the first covering contour profile.

2. Optical element according to the previous claim, regarding the remedy and / or the further remedy be transparent.

3. Optical element according to one of the preceding claims, whereby the means and the further means designed to generate opposing forces on the cover.

4. Optical element according to one of the preceding claims, whereby the means and the further be designed to generate an attractive force on the cover.

5. Optical element according to one of the preceding claims, whereby the means and the further means be individually controllable.

6. Optical element according to one of the preceding claims, where the means and / or the further means each comprise at least one of the following: an electrical component, such as a electrode, a pressure-based component, a thermal-based component, an optical component, such as a photonic circuit.

7. Optical element according to one of the preceding claims, whereby the means and the further means be identical in type, whereby they are preferably identical.

8. Optical element according to one of the claims 1 6, whereby the means and the further be by means of different types.

9. Optical element according to one of the preceding claims, comprising further support to one side of the cover opposite the support, whereby a part of the second surface of the cover is attached to the further support.

10. Optical element according to one of the preceding claims, further comprising: - a substrate on one side of the support opposite the cover, and possibly: - a further substrate on one side of the cover opposite the substrate.

11. Optical element according to one of the preceding claims, where the optical element is planar-symmetric with the covering as the plane of symmetry.

12. Procedure for operating an optical element according to one of the preceding facility conclusions, comprising the simultaneous or alternate operation of the means and the further means.

13. Method of working according to the previous conclusion, regarding the ground of appeal and the further ground of appeal be served differently, for example to different degrees.

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