US-20260126697-A1 - LIGHT MODULATOR AND SUBSTRATE HAVING AN ENERGY CONVERSION LAYER

US20260126697A1US 20260126697 A1US20260126697 A1US 20260126697A1US-20260126697-A1

Abstract

Some embodiments are directed to a transparent substrate for use in a light modulator. The light modulator has an optical layer. The transparent substrate has at least one electrode system applied on the substrate. The electrode system comprises a stack of a substrate-side electrode, an energy conversion layer, and an optical layer-side electrode. The optical layer-side electrode is arranged to modulate an electric field in the optical layer. The energy conversion layer is configured to convert between energy external to the substrate and a voltage difference between the substrate-side electrode and the optical layer-side electrode.

Inventors

Romaric Mathieu Massard
Steven Van Mullekom
Anthony John Slack

Assignees

ELSTAR DYNAMICS PATENTS B.V.

Dates

Publication Date: 20260507
Application Date: 20240411
Priority Date: 20230414

Claims (20)

1 . A transparent substrate for use in a light modulator, the light modulator having an optical layer, the transparent substrate having at least one electrode system applied on the substrate, the electrode system comprising a stack of a substrate-side electrode, an energy conversion layer, and an optical layer-side electrode, the optical layer-side electrode being arranged to modulate an electric field in the optical layer, the energy conversion layer being configured to convert between energy external to the substrate and a voltage difference between the substrate-side electrode and the optical layer-side electrode, wherein the electrode system is arranged across the substrate in multiple lines, the substrate-side electrode and the optical layer-side electrode being arranged in multiple electrode lines, wherein the multiple electrode lines in the substrate-side electrode of the at least one electrode system and the multiple electrode lines in the optical layer-side electrode of the at least one electrode system align when projected orthogonally on the substrate, wherein the energy conversion layer is arranged across the substrate in multiple lines, a dielectric being arranged between the multiple lines of the energy conversion layer the energy conversion layer of the at least one electrode system extends beyond the borders of the multiple electrode lines in the substrate-side electrode and beyond the borders of the optical layer-side electrode when projected orthogonally on the substrate.
2 . The substrate as in claim 1 , wherein the energy conversion layer comprises one or more of the following list: a photovoltaic stack configured to convert light incident on the substrate to the voltage difference, a thermoelectric stack configured to convert a heat difference between two sides of the substrate in the voltage difference, a radio frequency energy scavenger layer, an LED configured to convert the voltage difference to light.
3 . The substrate as in claim 1 , wherein the optical layer-side electrode is arranged as a voltage reference for the energy conversion layer.
4 . The substrate as in claim 1 , wherein the substrate-side electrode and/or the optical layer-side electrode comprises a large-area electrode.
5 . A substrate as in claim 1 , wherein the at least one electrode system comprises a first electrode system and a second electrode system, the multiple lines of the first electrode system being interdigitated with the multiple lines of the second electrode system, a dielectric being applied between the interdigitated lines of the first and second electrode system, electrically isolating the substrate-side electrode and the optical layer-side electrode of the first electrode system from the substrate-side electrode and the optical layer-side electrode of the second electrode system.
6 . A substrate as in claim 1 , wherein the substrate-side electrode, the optical layer-side electrode, and the energy conversion layer are transparent, and/or the substrate-side electrode, the optical layer-side electrode, are transparent, the energy conversion layer is arranged across the substrate in a pattern across the substrate, covering at most part of the substrate, and/or the substrate-side electrode, and/or the optical layer-side electrode comprises two layers, a transparent large area electrode, and a patterned non-transparent electrode, and/or the optical layer-side electrode comprises a transparent, large-area electrode, and a patterned, reflective electrode aligned with the energy conversion layer.
7 . A substrate, as in claim 1 , comprising multiple energy conversion layers.
8 . A transparent substrate as in claim 1 , wherein a high conductivity material is applied to the substrate.
9 . A light modulator comprising a first substrate as in claim 1 , and a second substrate arranged opposite the first substrate, an optical layer extending between the first and second substrate, at least one optical layer-side electrode is applied on the second substrate, optical properties of the light modulator are modifiable by applying an electric potential to at least the optical layer-side electrode of the at least one electrode system, energy is converted to or from an electric voltage difference between the substrate-side electrode and the optical layer-side electrode by the energy conversion layer.
10 . A light modulator as in claim 9 , comprising a light modulator drive system and a light modulator drive system being configured to control an electric potential on optical layer-side electrodes of the first and/or second substrate, and a power generation system configured to generate an electric current from the energy conversion layer on at least the first substrate, wherein the optical layer-side electrode on the first substrate is selectively connected to the power generation system.
11 . A light modulator as in claim 9 , wherein the optical layer-side electrode on the first substrate is connected to the power generation system through a first selective connection, and to the light modulator drive system through a second selective connection, the first and second selective connection being controlled to connect the optical layer-side electrode selectively to the light modulator drive system or the power generation system.
12 . A light modulator as in claim 9 , wherein the electrode being arranged across the second substrate in multiple electrode lines, or the second substrate is a substrate according to any of claims 1-8 , and wherein optical properties of the light modulator are further modifiable by applying an electric potential to the optical layer-side electrode of the second substrate.
13 . A light modulator as in claim 9 , the optical layer comprising a fluid, the fluid comprising particles, the light modulator being configured to apply an electric potential to the optical layer-side electrode of the at least on electrode system causing modulation of an electric field in the optical layer providing electrophoretic and/or dielectrophoretic movement of the particles in the optical layer causing modulation of light passing through the substrates.
14 . An electrophoretic light modulator as in claim 9 , the particles being electrically charged or chargeable, at least a first electrode system and a second electrode system being applied on the first substrate, the multiple lines of the first electrode system and the second electrode system alternating on the first substrate, at least a first optical layer-side electrode and a second optical layer-side electrode being applied on the second substrate, multiple lines of the first optical layer-side electrode and the second optical layer-side electrode alternating on the second substrate.
15 . A light modulator as in claim 14 , the light modulator drive system configured to control an electric potential on the optical layer-side electrodes of the second substrate and the optical layer-side electrodes in the electrode systems on the first substrate to obtain an electro-magnetic field between the multiple optical layer-side electrodes providing electrophoretic movement of the particles towards or from one of the multiple optical layer-side electrodes causing modulation of the optical properties of the light modulator.
16 . A light modulator as in claim 9 , the light modulator drive system being configured to control the electric potential as an alternating current or voltage.
17 . An electrophoretic light modulator as in claim 1 , wherein the light modulator drive system is configured to maintain the light modulator in a non-transparent state, by controlling to be equal the potential on the first optical layer-side electrode on the second substrate and the second optical layer-side electrode on the second substrate to be equal to the potential on the optical layer-side electrode of the first electrode system and the optical layer-side electrode of the second electrode system.
18 . An electrophoretic light modulator as in claim 1 , wherein the light modulator drive system is configured to transition the light modulator from a less-transparent state to a more transparent state, by controlling the first optical layer-side electrode and the second optical layer-side electrode on the second substrate to have different potentials than the opposite optical layer-side electrode on the first substrate.
19 . An electrophoretic light modulator as in claim 1 , wherein the light modulator drive system is configured to transition the light modulator from a more-transparent state to a less-transparent state by controlling the potential on the substrate-side electrode and the optical layer-side electrode in the first electrode system to both be offset in a first direction, and by controlling the potential on the substrate-side electrode and the optical layer-side electrode in the second electrode system to both be offset in a second direction opposite the first direction, and controlling the potential on the first optical layer-side electrode and the second-optical layer-side electrode on the second substrate to be equal the optical layer-side electrode opposite on the first substrate.
20 . A light modulator as in claim 1 , comprising multiple energy conversion layers of one or more different types, and one optical layer, or one energy conversion layers, and multiple optical layers, or multiple energy conversion layers of one or more different types, and multiple optical layers.

Description

TECHNICAL FIELD The presently disclosed subject matter relates to a transparent substrate for use in a light modulator, a light modulator, a light modulator method, a system, a computer storage medium, method of manufacturing a substrate. BACKGROUND A known light modulator is disclosed in WO2022023180, included herein by reference. The known light modulator comprises transparent or reflective substrates. Multiple electrodes are applied to the substrates in a pattern across the substrate. A controller may apply an electric potential to the electrodes to obtain an electro-magnetic field between the electrodes providing electrophoretic movement of the particles towards or from an electrode. SUMMARY It would be advantageous to have an improved light modulator, and an improved substrate that may be used therein. An embodiment of a transparent substrate for use in a light modulator comprises: a substrate-side electrode, an energy conversion layer, and an optical layer-side electrode. The optical layer-side electrode is arranged to modulate an electric field in an optical layer of the light modulator. The energy conversion layer is configured to convert between energy external to the substrate and a voltage difference between the substrate-side electrode and the optical layer-side electrode. In an embodiment, the energy conversion layer comprises a photovoltaic stack configured to convert light incident on the substrate to the voltage difference. However, different choices for the energy conversion layer can be made. Having an energy conversion layer in the substrate of a light modulator is efficient, as it generates energy. Moreover, the energy conversion layer can be employed in locations where otherwise no energy conversion, e.g., solar cells, are possible, e.g., as they are needed for glazing. Furthermore, fewer electrodes are needed for the combination of the energy conversion layer and the light modulator, then would be needed for an energy conversion layer and a light modulator separately. Furthermore, the optical layer, especially fluid-based, e.g., e-ink, based optical layers, benefit the system further by acting as a heat sink for the energy conversion layer. An aspect is a light modulator method for a light modulator, a method of manufacturing a substrate as in an embodiment. An embodiment of the method may be implemented on a computer as a computer implemented method, or in dedicated hardware, or in a combination of both. Executable code for an embodiment of the method may be stored on a computer program product. Examples of computer program products include memory devices, optical storage devices, integrated circuits, servers, online software, etc. Preferably, the computer program product comprises non-transitory program code stored on a computer readable medium for performing an embodiment of the method when said program product is executed on a computer. In an embodiment, the computer program comprises computer program code adapted to perform all or part of the steps of an embodiment of the method when the computer program is run on a computer. Preferably, the computer program is embodied on a computer readable medium. Another aspect of the presently disclosed subject matter is a method of making the computer program available for downloading. BRIEF DESCRIPTION OF DRAWINGS Further details, aspects, and embodiments will be described, by way of example only, with reference to the drawings. Elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. In the figures, elements which correspond to elements already described may have the same reference numerals. In the drawings, FIG. 1a schematically shows an example of an embodiment of a building block, FIG. 1b schematically shows an example of an embodiment of a substrate, FIG. 1c schematically shows an example of an embodiment of a substrate, FIG. 1d schematically shows an example of an embodiment of a substrate, FIG. 1e schematically shows an example of an embodiment of a substrate, FIG. 1f schematically shows an example of an embodiment of a substrate, FIG. 1g schematically shows an example of an embodiment of a light modulator, FIGS. 2a-2f schematically show an example of an embodiment of a substrate, FIG. 3a schematically shows an example of an embodiment of a light modulator, FIG. 3b schematically shows an example of an embodiment of a light modulator, FIG. 3c schematically shows an example of an embodiment of a car, FIGS. 4a-4c schematically show an embodiment of a light modulator, FIG. 5 schematically shows materials used in an embodiment of a light modulator, FIGS. 6a, 6b schematically show examples of embodiments of a two-electrode light modulator, FIGS. 7a-7g schematically show examples of embodiments of a two-electrode light modulator, FIG. 8a schematically shows examples of embodiments of a three-electrode light modulator, FIGS. 9a-9e schematically show examples of embodiments of a four-ele