JP2023148622A - Dimming device - Google Patents

Abstract

To provide a dimming device with which, when connecting an ITO and an FPC in the power supply connecting part of the dimming device using an ACF, it is possible to suppress the occurrence of cracks to the ITO as will be caused by conductive particles included in the ACF and prevent the drive voltage from lowering due to a rise of connection resistance between the FPC and a dimming sheet.SOLUTION: Provided is a dimming device comprising a dimming sheet which is capable of switching between an opaque state and a transparent state in accordance with an applied voltage, and a power supply connection unit for connecting the dimming sheet to an external power supply. The dimming sheet is composed by being sandwiched between a dimming layer and a transparent substrate in which a transparent electrode layer for applying a voltage to the dimming layer is formed. The power supply connection unit electrically connects the transparent electrode layer and an FPC via an ACF and has a mechanically bonded structure, with a conductive substance further laminated between the transparent electrode layer and the ACF, the conductive substance being formed from a material that is more flexible than the transparent electrode layer.SELECTED DRAWING: Figure 1

Description

The present invention relates to a light control device equipped with an optical element that controls the transmission state of light by electrical control, and particularly relates to a light control device in which a positioning pattern for connecting a light control film and a flexible printed circuit board is formed. .

Conventionally, various devices have been proposed regarding light control films using liquid crystal panels that are attached to windows to control the transmission of external light. The light control film is equipped with a liquid crystal layer held between a pair of transparent electrodes made of ITO (Indium Tin Oxide), and the alignment state of liquid crystal molecules contained in the liquid crystal layer is changed by the voltage applied to the transparent electrodes. An example is a type that can be switched between an opaque state (or cloudy state) that scatters light and a transparent state that transmits incident light (for example, see Patent Document 1).

By fixing this type of light control film to a transparent substrate such as glass, it can be used not only for buildings but also for vehicle windows, exhibition windows, partitions, etc., and can be used in both private and public spaces. In addition to equipment that separates spaces, such as separating spaces, there have also been proposals for its use as a screen for displaying images.

Such a light control film has a power connection for connecting the transparent electrode layer to a power source. As a power connection part for supplying power from an external power source, the transparent electrode ITO and FPC (flexible printed circuit board) are electrically connected using an ACF (conductive adhesive layer) and mechanically connected as a low-cost and simple structure. A structure has also been adopted in which the wiring is drawn out by adhering the wires (see Patent Document 2). The connection using FPC and ACF has a planar joint structure, which improves the durability of the joint against shaking and impact during transportation and installation of the dimming unit.

At this time, the power supply connection part of the light control film and the FPC are aligned so that the connection terminal of the power supply connection part of the light control film and the connection terminal of the FPC are not connected in a shifted state.

FIG. 1 shows a front view of the light control device. As shown in FIG. 1, the power connection parts 16A and 16B are provided at the ends of both sides of the light control film 11, and the transparent electrode layer 13B on the other side corresponds to the corresponding part of the power connection part 16A on one side. The connecting terminal of the FPC 17A is connected to the exposed transparent electrode layer 13A of the power supply connecting part 16A via the ACF 19A (see FIG. 2). The conventional position adjustment when connecting the FPC 17A to the power supply connection part 16A is performed in the vertical direction (Y direction) as shown in FIG. The end edge 14 of the light control film 11 near the power connection part 16A and the alignment mark 15A formed by the Cu pattern on both sides of the FPC are used as a reference, and in the horizontal direction (X direction), the outer side 5 of the light control film 11 is aligned. Alternatively, the cut line 6 of the portion where the transparent electrode layer on the other side has been removed is aligned with one end edge 7 in the width direction of the FPC, and the connection is made using the reference. In a similar manner, the connection terminal of the FPC 17B is also connected to the power supply connection section 16B on the other side.

However, the alignment mark is not located at a location corresponding to the connection area on the light control film 11, and the alignment reference 7 of the FPC in the X direction and the alignment reference (5 or 6) of the light control film 11 are formed at separate positions. Therefore, the positioning accuracy by the positioning camera is poor, and the problem is that the transparent electrode layers 13A, 13B of the power supply connection parts 16A, 16B of the light control film 11 and the terminal groups formed on the FPCs 17A, 17B are not connected accurately. there were.

Japanese Patent Application Publication No. 2017-187775 Patent No. 6439029

The present invention has been made in view of these problems, and an object of the present invention is to provide a light control device using an FPC that improves the positioning accuracy of the light control film and the FPC.

As a means for solving the above problems, a first aspect of the present invention includes:
The light control device includes a light control film capable of switching between an opaque state and a transparent state according to an applied voltage, and a conductive part of an FPC connected to a power supply connection part formed at an end of the light control film. hand,
The light control film is sandwiched between a transparent base material on which a light control layer and a transparent electrode layer for applying a voltage to the light control layer are formed,
The power supply connection part has a structure in which the transparent electrode layer and the FPC are mechanically bonded while being electrically connected via an ACF,
Alignment marks in the vertical direction (Y direction) are provided on both ends of the FPC, and the alignment marks are aligned with the edges of the light control film near the power supply connection part, and the light control film and FPC are aligned. The connection is positioned in the vertical direction (Y direction).
The transparent electrode layer is provided with a notch or a convex shape on the edge near the power supply connection part, one side in the width direction of the notch or convex shape is used as a reference line, and the width of the FPC is set on the reference line. The light control device is characterized in that the connection between the light control film and the FPC is positioned in the horizontal direction (X direction) by bringing one side of the light control film into contact with the FPC.

According to the present invention, positioning accuracy can be improved by forming a cutout or a convex shape having an alignment reference at a location corresponding to the connection area on the light control film. In order to position the connection between the light control film and the FPC in the X direction, a cutout or a convex shape is provided in the transparent electrode layer near the power supply connection part, so it is necessary to separately provide an alignment mark. Instead, positioning can be performed by abutting the references provided on the respective substrates, which has the effect of improving positioning accuracy.

Moreover, the second aspect of the present invention is
The notch or convex shape may have a reference line that can measure the distance in the X direction from one side in the width direction of the FPC, and may be linear, square, or triangular. .

In a light control device using FPC, it is possible to provide a light control device that improves positioning accuracy between the light control film and the FPC by providing a cutout or a convex shape in the transparent electrode layer near the power connection part of the light control film. It is.

FIG. 1 is a front view of a light control device according to an embodiment of the present invention. FIG. 3 is a schematic cross-sectional view of a power supply connection portion formed on one surface of the light control device. FIG. 7 is a schematic cross-sectional view of a power supply connection portion formed on the other surface of the light control device. FIG. 3 is a diagram illustrating a conventional positioning method for connecting a light control film and an FPC. FIG. 3 is a diagram illustrating a method for positioning the connection between a light control film and an FPC according to the present invention. FIG. 3 is a diagram showing the shape of a notch according to the present invention. FIG. 3 is a diagram showing the shape of a convex shape according to the present invention.

An example of the structure of a light control device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a front view of a light control device according to an embodiment of the present invention. As shown in FIG. It is attached to the plate 20. The light control device 10 is mainly made of flexible and thin material, and is highly flexible. The support base material is a transparent plate-like member made of glass, resin, or the like, and may be flat or curved. The transparent plate 20 may be a building material such as a partition or a glass wall other than a window glass, or may be a vehicle member such as an automobile window glass.

As can be seen from FIG. 1, the light control device 10 has a substantially rectangular shape, and the light control film 11, which occupies most of the light control device 10, includes a light control layer (liquid crystal layer) 12 and a light control layer (liquid crystal layer) 12. The layer 12 is sandwiched between a pair of transparent electrode layers 13A and 13B that apply a voltage to the layer 12 (see FIGS. 2 and 3). A power supply connection part 16A for supplying power from an external power supply 18A is connected to an end of the transparent electrode layer 13A, and a power supply connection part 16B for supplying power from an external power supply 18B is connected to an end of the transparent electrode layer 13B. There is.

Each of the pair of transparent electrode layers 13A and 13B that applies a voltage to the light control layer 12 is a transparent layer that has conductivity. Examples of the materials constituting the transparent electrode layers 13A and 13B include indium tin oxide (ITO), fluorine-doped tin oxide (FTO), tin oxide, zinc oxide, carbon nanotubes (CNT), and poly(3,4-ethylenedioxide). Examples include polymers containing oxythiophene (PEDOT). The preferred thickness of the transparent electrode layers 13A and 13B is approximately 80 nm or more and 150 nm or less.

The power supply connection parts 16A and 16B are located at the ends of the transparent electrode layers 13A and 13B along one side of the light control film. The side on which the power supply connection parts 16A and 16B are arranged may be any side of the rectangle, and may be set according to the arrangement of the transparent plate 20 and the drive circuit (not shown). Further, the power supply connecting parts 16A and 16B may be arranged at a position including the center of the one side, or, as shown in FIG. 1, may be arranged at a position including the end of the one side. The power supply connection parts 16A and 16B are provided with lead wires (not shown), and the lead wires extend outside the light control film 11 and are connected to the drive circuit.

Also, a part of the transparent electrode layer on the other side corresponding to the corresponding part of the transparent electrode layers 13A and 13B to which the power supply connection parts 16A and 16B are connected (a part of the transparent electrode layer 13B and a part of the transparent electrode layer 13A, respectively) are cut and removed, and the power supply connection parts 16A and 16B are connected to the light control layer 12 and the area exposed from the transparent electrode layer on the other side.

As shown in FIGS. 2 and 3, the transparent electrode layers 13A and 13B are attached to the transparent plate 20 via the adhesive layer 25, and the transparent electrode layer 13A is in contact with one surface of the light control layer 12. The power supply connection portion 16A is connected to a region of the transparent electrode layer 13A exposed from the light control layer 12 and the other transparent electrode layer 13B. The transparent electrode layer 13B is in contact with the other surface of the light control layer 12. The power supply connection portion 16B is connected to a region of the transparent electrode layer 13B that is exposed from the light control layer 12 and the other transparent electrode layer 13A, and faces the transparent plate 20.

The power supply connection parts 16A, 16B include ACFs 19A, 19B which are conductive adhesive layers bonded to the transparent electrode layers 13A, 13B, and flexible printed circuit boards FPCs 17A, 17B bonded by the ACFs 19A, 19B. The power supply connection parts 16A, 16B further include lead wires connected to the FPCs 17A, 17B. The lead wires are connected to a drive circuit that converts the voltage supplied from the power source into a drive voltage, and the drive voltage is applied to the transparent electrode layers 13A, 13B through the power supply connections 16A, 16B. Therefore, by relatively aligning the power supply connection parts 16A, 16B and the terminals provided on the FPCs 17A, 17B, the light control film 11 and the FPCs 17A, 17B are electrically connected, respectively.

FIG. 5 shows rectangular notches 30 formed on both sides of the position where the FPC 17A is connected to the corresponding location of the power supply connection portion 16A in the light control film 11 according to the present invention. One side 31 in the width direction of this notch 30 and one side 7 in the width direction of the FPC 17A are used as the alignment reference in the X direction, and the alignment marks 15A in the Y direction formed at both ends of the FPC and the The connection between the light control film and the FPC 17A is determined and connected using the end side 4 as an alignment reference in the Y direction. Further, the light control film 11 and the FPC 17B on the other side are also connected using the same positioning method. Note that the rectangular notch 30 may be formed only on one side of the connection position.

In this way, the notch 30 is formed close to both sides of the position where the light control film 11 and the FPCs 17A and 17B are connected, so that one side 31 of the notch 30 in the width direction and one side of the FPC 17A in the width direction By using the side 7 as the alignment reference in the X direction, it becomes possible to perform positioning in the X direction with high accuracy using the positioning camera.

Furthermore, as shown in FIG. 6, the shape of the notch 30 according to the present invention may be triangular or linear, as long as it has a reference line in the X direction, in addition to the rectangular shape. Further, for the same reason, a convex shape may be used instead of the notch. As the convex shape, a square convex shape, a triangular convex shape, an FPC part convex shape, etc. as shown in FIG. 7 can be used.

Positioning using the above-mentioned notch or convex positioning pattern 30 is performed, for example, by installing a CCD camera, an illumination light source, etc., and observing the vicinity of the positioning pattern 30 under magnification. The vicinity of the positioning pattern 30 is illuminated with an illumination light source, and an image of the vicinity of the positioning pattern 30 captured by a CCD camera is displayed on a monitor or the like. Alignment is performed by moving the FPCs 17A and 17B so that the reference lines are in contact with each other while watching this monitor, and in a state where the light control film 11 and the FPCs 17A and 17B are aligned, they are bonded together via the ACFs 19A and 19B. Thereby, the light control film 11 and the FPCs 17A and 17B can be connected with high accuracy.

According to the above, one side 7 in the width direction of the FPCs 17A, 17B is taken as a reference line in the By simply aligning the reference line along one side of the direction and placing them in contact with each other, the terminals of FPCs 17A and 17B will automatically match the terminals of power supply connections 16A and 16B. By aligning to In other words, by using the notch or convex positioning pattern 30 provided on the transparent electrode layers 13A, 13B as a positioning jig, the FPCs 17A, 17B can be positioned easily and inexpensively.

Therefore, according to the present invention, it is possible to provide a light control device in which the light control film 11 and the FPCs 17A and 17B can be connected with high precision both in the horizontal and vertical directions.

4... Edge of light control film 5... Side of light control film 6... Transparent electrode layer cut line 7... Side of FPC 10... Light control device 11... Light control film 12. ...Dimmer layer 13A, 13B...Transparent electrode layer 15...Alignment mark 16A, 16B...Power connection part 17A, 17B...FPC
18A, 18B...External power supply 19A, 19B...ACF
20... Transparent plate 25... Adhesive layer 30... Notch or convex shape (positioning pattern)

Claims (2)

The light control device includes a light control film capable of switching between an opaque state and a transparent state according to an applied voltage, and a conductive part of an FPC connected to a power connection part formed at an end of the light control film. hand,
The light control film is sandwiched between a transparent base material on which a light control layer and a transparent electrode layer for applying a voltage to the light control layer are formed,
The power supply connection part has a structure in which the transparent electrode layer and the FPC are mechanically bonded while being electrically connected via an ACF,
Alignment marks in the vertical direction (Y direction) are provided at both ends of the FPC, and the alignment marks are aligned with the edges of the light control film near the power connection part, and the light control film and FPC are aligned. The connection is positioned in the vertical direction (Y direction).
The transparent electrode layer is provided with a notch or a convex shape on the edge near the power supply connection part, one side in the width direction of the notch or convex shape is used as a reference line, and the width of the FPC is set on the reference line. A light control device characterized in that the connection between the light control film and the FPC is positioned in the horizontal direction (X direction) by bringing one side of the light control film into contact with the FPC. The light control device according to claim 1, wherein the cutout or convex shape is linear, square, or triangular.

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