Search

EP-4402534-B1 - ELECTRO-OPTIC DEVICE WITH VARIABLE TRANSMISSIVITY

EP4402534B1EP 4402534 B1EP4402534 B1EP 4402534B1EP-4402534-B1

Inventors

  • SAENGER NAYVER, MARIO F.

Dates

Publication Date
20260506
Application Date
20220916

Claims (12)

  1. An electro-optic device with variable transmissivity comprising: a first substrate (110) having a first surface (111) and a second surface (112); a second substrate (120) having a third surface (123) and a fourth surface (124), the second substrate (120) disposed in a substantially parallel and spaced apart relationship relative the first substrate (110); a first electrode (130a) associated with the second surface (112); a second electrode (130b) associated with the third surface (123); and an electro-optic medium (160) disposed between the first and second electrodes (130a, 130b); wherein at least one of the first and second electrodes (130a, 130b) comprises: a first conductive layer (131) in electrical communication with at least one of an electrical contact and a bus, the first conductive layer (131) distributed across a plurality of points; characterized in that said at least one of the first and second electrodes (130a, 130b) further comprises: a second conductive layer (138) disposed between the first conductive layer (131) and the electro-optic medium (160); and an insulating layer (136) disposed between the first and second conductive layers (131, 138), the insulating layer (136) patterned with a plurality of holes (137) aligned with the plurality of points operable to allow electrical communication between the first and second conductive layers (131, 138); and in that the first conductive layer (131) has an electrical distribution pattern, the electrical distribution pattern comprising one or more electrical pathways (133) defined by an absence of part of the first conductive layer (131) within a plane of the layer.
  2. The electro-optic device of claim 1, wherein the points are distributed substantially uniformly across an extent of the first conductive layer (131).
  3. The electro-optic device of claim 1, wherein resistance along the electrical pathways (133) between the at least one of an electrical contact and a bus and each of the points is substantially equal.
  4. The electro-optic device of claim 1, wherein the one or more electrical pathways (133) are separated into a plurality of electrically isolated groups corresponding to a plurality of zones (101) of the device such that the electro-optic medium (160) may substantially selectively vary an activation of the electro-optic medium (160) within each zone.
  5. The electro-optic device of claim 4, wherein for each group, resistance along the electrical pathways (133) between the at least one of the electrical contact and the bus and each of the points within the corresponding zone (101) is substantially equal.
  6. The electro-optic device of claim 1, wherein the electrical pathways (133) have varying widths relative one another to change the resistance of the electrical pathways (133) relative one another.
  7. The electro-optic device of claim 1, wherein the electrical pathways (133) form one or more manifolds arranged in a hub and spoke configuration.
  8. The electro-optic device of claim 7, wherein the width of the electrical pathways (133) forming spokes of the manifold are proportional to the length thereof.
  9. The electro-optic device of claim 1, wherein the holes (137) are filled with an electrically conductive material.
  10. The electro-optic device of claim 1, wherein at least one of a shape and a size of the holes (137) is varied to change an electrical resistance therethrough, increasing uniformity between electrical potentials at the locations of the holes (137).
  11. The electro-optic device of claim 1, wherein the electrical potentials at the points are substantially equal.
  12. The electro-optic device of claim 1, wherein the second conductive layer (138) is substantially uniform.

Description

FIELD OF INVENTION The present invention relates in general to electro-optic elements and, more particularly, to electrodes of electro-optic elements. BACKGROUND Electro-optic elements are increasingly common in various devices, such as dimmable windows or rearview assemblies. These electro-optic elements rely on activation of an electro-optic medium disposed between two electrodes. The electro-optic medium may be variably activated based, at least in part, on the electrical potential to which it is exposed. The electrodes of these electro-optic elements are commonly conductive layers disposed across a viewing region of the device. However, these electrodes have sheet resistance, which increases across the respective electrode as the distance to an electrical contact or bus increases. This increase in sheet resistance may case a reduction in the electrical potential. This may be referred to as a potential drop. Therefore, the electrical potential applied by the electrode may not be uniform there across. This lack of uniformity may result in inconsistent activation of the electro-optic medium across the element, which may be visually apparent. Accordingly, there is a need for electro-optic elements with improved electrodes. US 2019/227357 Al describes a switchable glazing unit comprising a glazing panel spaced apart from a pane of glazing material by a perimeter seal is described. The glazing panel comprises first and second glass sheets. A first electrode layer is on a first major surface of the first glass sheet and a second electrode layer is on a first major surface of the second glass sheet. A layer of liquid crystal material is between the first electrode layer and the second electrode layer. When no voltage is applied to the first and second electrode layers, the liquid crystal layer has a first opacity, and upon applying a suitable voltage between the first and second electrode layers, the liquid crystal layer has a second opacity different to the first opacity. Methods of making such a switchable glazing unit are also described. US 2017/115521 A1 describes a conducting film or device multilayer electrode including a substrate and two transparent or semitransparent conductive layers separated by a transparent or semitransparent intervening layer. The intervening layer includes electrically conductive pathways between the first and second conductive layers to help reduce interfacial reflections occurring between particular layers in devices incorporating the conducting film or electrode. BRIEF DESCRIPTION OF FIGURES In the drawings: Figure 1 is a cross-sectional schematic representation of an electro-optic element;Figure 2a is a cross-sectional schematic representation of an embodiment of an electrode of an electro-optic element;Figure 2b is a perspective view of an implementation of an electrode of an electro-optic element not according to the claimed invention;Figure 2c is a perspective view of an embodiment of an electrode of an electro-optic element according to the claimed invention;Figure 2d is an exploded perspective view of a portion of an implementation of an electrode of an electro-optic element not according to the claimed invention;Figure 2e is an exploded perspective view of a portion of an embodiment of an electrode of an electro-optic element according to the claimed invention;Figure 3a is a schematic representation of an implementation of a layer of an electrode of an electro-optic element not according to the claimed invention;Figure 3b is a schematic representation of an embodiment of a layer of an electrode of an electro-optic element according to the claimed invention;Figure 4a is a schematic representation of an embodiment of an electrical pathway manifold;Figure 4b is a schematic representation of an embodiment of an electrical pathway manifold;Figure 5 is a schematic representation of an embodiment of a layer of an electrode of an electro-optic element; andFigure 6 is a schematic representation of an embodiment of a layer of an electrode of an electro-optic element. DETAILED DESCRIPTION For the purposes of description herein, specific devices and processes illustrated in the attached drawings and described in this disclosure are simply exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific characteristics relating the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise. The present disclosure is directed to an electro-optic element with improved electrodes. Accordingly, Figure 1 illustrates a cross-sectional representation of an embodiment of an electro-optic element 100. Electro-optic element 100 may comprise a first substrate 110, a second substrate 120, at least two electrodes 130, a seal 140, a chamber 150, an electro-optic medium 160. Further, electro-optic element 100 may be operable between a substantially activated state and a substantially un-activated state. Operation be