Abstract: The present invention relates to a method for making an electrowetting display device comprising a plurality of picture elements and a first support plate and a second support plate. Each picture element comprises a space between the first support plate and the second support plate. The method comprises the steps of: providing the first support plate with an electrode structure; arranging an insulating layer on the electrode structure, the insulating layer having a thickness and a hydropobic surface facing the space; temporarily applying an electric field across the thickness of the insulating layer to reduce permanently the hydrophobicity of a predetermined area of the surface. The invention further relates to an electrowetting display device and a use of an area of reduced hydrophobicity in an electrowetting device.

Abstract: The present invention relates to an electrowetting element for a display device, a display device and a control system for controlling at least one electrowetting element. The electrowetting element comprises: a radiation valve comprising a first fluid and a second fluid immiscible with the first fluid, wherein the first and second fluids are configurable to change a characteristic of radiation passing through at least one of the first and second fluids; and an electrically switchable part switchable between a reflective mode for reflecting radiation incident on the switchable part and towards the radiation valve, and a transmissive mode for transmitting radiation incident on the switchable part through the switchable part and towards the radiation valve.

Abstract: A method of driving an electrowetting display device that includes a display element having a cavity; a first fluid and a second fluid within the cavity, the first fluid being immiscible with the second fluid; a surface facing the cavity; and a first electrode. The display device includes a control system for applying a voltage to the first electrode to provide a display state in response to a signal level of the voltage, wherein the control system is arranged to configure the signal level throughout a display period such that the second fluid adjoins at least a minimum area of the surface, the minimum area being greater than a zero area. The method includes applying at least one display signal level during the display period, the at least one display signal level configured such that the first fluid and the second fluid adjoin the surface throughout the display period.

Abstract: Display device is based on layer break up or layer displacement having at least two different states, in which one of the fluids, e.g., oil in a first state, adjoins at least a first support plate and, in the second state, the other fluid at least partly adjoins the first support plate. In one embodiment, a picture element corresponds to a substantially closed space and, in the first state, the other fluid layer substantially completely adjoins both support plates and is divided in two sub-layers. This makes it possible, on the one hand, to use lower voltages to make displacement occur. On the other hand, this opens the opportunity to color displays.

Abstract: An optical switch, e.g. a display cell based on layer displacement or layer break up having at least two different states, in which one of the fluids e.g. oil in a first state adjoins at least a first support plate and in the second state the other fluid at least partly adjoins the first support plate. Part of an otherwise homogeneous electrode is removed to realize oil motion control.

Abstract: An optical switch, e.g., a display cell based on layer displacement or layer break up having at least two different states, in which one fluid, e.g. oil, in a first state adjoins at least a first support plate, and in the second state, another fluid at least partly adjoins the first support plate. Part of an otherwise homogeneous electrode is removed to realize oil motion control.

Abstract: Display device is based on layer break up or layer displacement having at least two different states, in which one of the fluids, e.g., oil in a first state, adjoins at least a first support plate and, in the second state, the other fluid at least partly adjoins the first support plate. In one embodiment, a picture element corresponds to a substantially closed space and, in the first state, the other fluid layer substantially completely adjoins both support plates and is divided in two sub-layers. This makes it possible, on the one hand, to use lower voltages to make displacement occur. On the other hand, this opens the opportunity to color displays.

Abstract: A transflective display device has a viewing side (7) and a rear side (8) and comprises a plurality of electrowetting elements (2) having a first support plate (5) facing the viewing side and a second support plate (6) facing the rear side. Each electrowetting element comprises a space (10) between the first support plate and the second support plate and includes a first fluid (11) and a second fluid (12) immiscible with each other. The second fluid absorbs at least a part of the optical spectrum. The position of the second fluid is controllable to cover a predetermined area (30) of the cross-section (29) of the space in the plane of the second support plate. A structured reflector (18) is arranged on the second support plate, comprising within the cross-section an area (33, 34) transparent for light incident from the rear side and an area (35, 36) reflective for light incident from the viewing side.

Abstract: Display device is based on layer break up or layer displacement having at least two different states, in which one of the fluids, e.g., oil in a first state, adjoins at least a first support plate and, in the second state, the other fluid at least partly adjoins the first support plate. In one embodiment, a picture element corresponds to a substantially closed space and, in the first state, the other fluid layer substantially completely adjoins both support plates and is divided in two sub-layers. This makes it possible, on the one hand, to use lower voltages to make displacement occur. On the other hand, this opens the opportunity to color displays.

Abstract: Optical apparatus for a display device. The optical apparatus comprises a cavity, and a first fluid (14) and a second fluid (16), held within the cavity, which are immiscible with each other. The first and second fluids are separated from each other by a meniscus (28) having a peripheral edge (30). The optical apparatus further comprises a fluid motion control system arranged to control movement of the first and second fluids within the cavity using electrostatic forces, and a first surface (26) and a second surface (21). The first surface has a different wettability for the first fluid than for the second surface. The first and second surfaces are arranged in the cavity to determine, upon activation of the fluid motion control system, a motion of the fluids within the cavity which has a preferential initiation at a first part (32) of the peripheral edge.

Abstract: Apparatus for providing a fluid meniscus with variable configurations by means of electrowetting. A fluid chamber (5) holds two different fluids (A, B) separated by a meniscus (14) of which the edge, having different sides, is constrained by the fluid chamber. A first electrowetting electrode (2a) is arranged to act on a first side of the meniscus edge and a second electrowetting electrode (2a?) is arranged to act separately on a second side of the meniscus edge. Selected meniscus configurations can be formed by providing selected voltages to the first and second electrowetting electrodes respectively.

Abstract: The present invention relates to an electrowetting system comprising an electrowetting element, a driver stage for applying a voltage to the element, and a switch connecting the electrowetting element to an output of the driver stage. The element comprises a first fluid and a second, immiscible fluid. The instantaneous position of the fluids is dependent on the voltage applied to the element, the voltage being set when the switch is closed. The voltage on the element is substantially maintained during a holding state longer than 70 ms when the switch is open.

Abstract: The present invention relates to an electrowetting element for a display device, a display device and a control system for controlling at least one electrowetting element. The electrowetting element comprises: a radiation valve comprising a first fluid and a second fluid immiscible with the first fluid, wherein the first and second fluids are configurable to change a characteristic of radiation passing through at least one of the first and second fluids; and an electrically switchable part switchable between a reflective mode for reflecting radiation incident on the switchable part and towards the radiation valve, and a transmissive mode for transmitting radiation incident on the switchable part through the switchable part and towards the radiation valve.

Abstract: A transflective display device has a viewing side (7) and a rear side (8) and comprises a plurality of electrowetting elements (2) having a first support plate (5) facing the viewing side and a second support plate (6) facing the rear side. Each electrowetting element comprises a space (10) between the first support plate and the second support plate and includes a first fluid (11) and a second fluid (12) immiscible with each other. The second fluid absorbs at least a part of the optical spectrum. The position of the second fluid is controllable to cover a predetermined area (30) of the cross-section (29) of the space in the plane of the second support plate. A structured reflector (18) is arranged on the second support plate, comprising within the cross-section an area (33, 34) transparent for light incident from the rear side and an area (35, 36) reflective for light incident from the viewing side.

Abstract: An optical element used, e.g., in an electrowetting display device having a number of pixels, is arranged in an array. Each optical element includes a cell filled with a polar conductive fluid, such as a water solution, and a non-polar fluid, such as an oil. The cell further includes first and second planar electrodes covered with first and second hydrophobic layers. By applying a voltage between the first fluid and alternately the first or second electrodes, the oil is forced to migrate between the first and second hydrophobic layers. Thus a bi-stable, energy efficient optical element is provided.

Abstract: Display device is based on layer break up or layer displacement having at least two different states, in which one of the fluids, e.g., oil in a first state, adjoins at least a first support plate and, in the second state, the other fluid at least partly adjoins the first support plate. In one embodiment, a picture element corresponds to a substantially closed space and, in the first state, the other fluid layer substantially completely adjoins both support plates and is divided in two sub-layers. This makes it possible, on the one hand, to use lower voltages to make displacement occur. On the other hand, this opens the opportunity to color displays.

Abstract: A switchable optical element has a fluid chamber including immiscible first and second bodies of fluid disposed relative to one another along an optical axis of the element. The second body of fluid is movable in a direction away from the optical axis (A) by electro-wetting action, giving the switchable optical element a changeable transmissivity along the optical axis.

Abstract: Display device based on layer break up or layer displacement having at least two different states, in which one of the fluids (5) e.g oil in a first state adjoins at least a first support plate (3) and in the second state the other fluid (6) at least partly adjoins the first support plate. In one embodiment a picture element corresponds to a substantially closed space and in the first state the other fluid layer substantially completely adjoins both support plates and is divided in two sub-layers. This makes it possible on the one hand to use lower voltages to make displacement occur. On the other hand this opens the opportunity to color displays.

Abstract: A display device or optical switch, based on layer break up or layer displacement having at least two different states, in which one of the fluids (5) e.g. oil in a first state adjoins at least a first support plate (3) and in the second state the other fluid (6) at least partly adjoins the first support plate, in which sub-picture elements are separated by areas (13) having a hydrophilic surface.

Abstract: An exemplary display device based on layer displacement having a perforated white substrate positioned close to a transparent substrate. Layer (fluid) displacement such as oil movement results in the (colored) oil film being pumped in a controlled manner above the white substrate. Fluids of three subtractive colors can be independently pumped to separate spaces. Based on the color strength of the used fluids good color rendition can be obtained for a flow channel thickness of less than 25 microns and therefore a total pixel thickness including the sub pixel reservoirs of less than 200 microns.