TWI463234B - Electrophoretic display module and manufacturing method thereof - Google Patents

Description

Electrophoretic display module and manufacturing method thereof

The present invention relates to a display module and a method of fabricating the same, and more particularly to an electrophoretic display module and a method of fabricating the same.

Since the development of electrophoretic displays tends to be the display of electronic readers with extremely fine display points, it is not very friendly for display devices for other purposes. In particular, electrophoretic displays have many limitations and difficulties in the manufacture of display devices other than very fine display point devices.

For example, an electrophoretic display is not heat-resistant, and a process of 80 degrees C or higher may damage the electrophoretic display, and thus cannot be manufactured by the current assembly work of electronic parts (240 degrees C or more). In order to achieve better control effect, the electrophoretic display and the transparent conductive layer covered by the surface must be closely adhered to the circuit board (the circuit board provides the circuit shape of the display shape), so the general electrophoretic display display is independent of the electrophoretic display. Fitted to the board (hard or flexible board), and then attached to a flexible printed circuit board (Flexible Printed Circuit Board) connected to the drive board.

Such a manufacturing process is less problematic in a simple display, and there is little problem when the display pixels are small, but there are many difficulties in designing a dot matrix display. First, the display pixels of the dot matrix display are few dozens. Points, many may reach hundreds of points (for example, 24*24 modules have 576 pixels), and the flexible circuit board is attached to the control circuit board, which is not only costly, but also the display signal stability is difficult to control.

Please refer to FIG. 5 , which illustrates a cross-sectional view of a conventional electrophoretic display module. The electrophoretic display module 100 includes a circuit substrate 106 and a driving circuit board 108. One surface of the circuit substrate 106 includes a pixel electrode layer 102, an electrophoretic display layer 101, and a transparent electrode layer 103 in this order from bottom to top. The drive circuit board 108 is soldered with a drive integrated circuit wafer 108a and other necessary electronic components (not shown). The circuit board 106 and the driving circuit board 108 are connected by the flexible circuit board 110. Therefore, it is necessary to reserve a bonding area outside the display area (because the gravity electrophoretic display causes damage) for the end portion 110a of the flexible circuit board 110 to be attached. If the electrophoretic display module 100 is to be combined into a large dot matrix display system, the bonding area may cause the display area to be inconsistent. In addition, when the circuit board 106 and the driving circuit board 108 are connected by the flexible circuit board 110, when the signal path required by the large dot matrix display system is excessive, the flexible circuit board 110 is attached and then connected to the driving circuit board 108, which is not only costly. Display signal stability is also difficult to control.

Accordingly, it is an object of the present invention to provide an improved electrophoretic display module and method of fabricating the same.

According to the above object, an electrophoretic display module includes a circuit substrate, a pixel electrode layer, an electrophoretic display layer, a transparent electrode layer, and at least one driving integrated circuit chip. The circuit substrate has two opposing surfaces. The pixel electrode layer is located on one of two opposite surfaces of the circuit substrate. The electrophoretic display layer is on the pixel electrode layer. The transparent electrode layer is on the electrophoretic display layer. The driving integrated circuit wafer is located on the other surface of the opposite surfaces of the circuit substrate, and the driving integrated circuit wafer is electrically connected to the transparent electrode layer and the pixel electrode layer directly via the inner layer circuit of the circuit substrate.

According to another embodiment of the invention, the circuit substrate is a rigid circuit substrate.

According to another embodiment of the invention, the circuit substrate is a rigid printed circuit board.

According to the above object, a method for manufacturing an electrophoretic display module is provided, which comprises the following steps. Bonding a pixel electrode layer to a surface of a circuit substrate. The at least one driving integrated circuit chip is bonded to the other opposite surface of the circuit substrate, and the driving integrated circuit wafer is electrically connected to the pixel electrode layer directly through the inner layer circuit of the circuit substrate. Bonding a pressure-proof fixture to another opposing surface of the circuit substrate. An electrophoretic display layer and a transparent electrode are laminated on the pixel electrode layer by a pair of rollers, and the integrated circuit chip is electrically connected to the transparent electrode layer and the pixel electrode layer directly through the inner layer circuit of the circuit substrate. . Remove the pressure-proof fixture.

According to another embodiment of the present invention, the pressure-resistant jig includes at least one component receiving groove for accommodating the driving integrated circuit chip.

According to another embodiment of the invention, the pressure-resistant jig has a uniform thickness.

According to another embodiment of the present invention, the uniform thickness of the pressure-resistant jig is greater than or equal to the thickness of the drive integrated circuit chip.

According to another embodiment of the present invention, the material of the pressure-proof jig comprises a metal material, bakelite or plastic.

It can be seen from the above that the electrophoretic display module and the manufacturing method thereof to which the present invention is applied have at least the following advantages:

1. Driving the integrated circuit directly drives the transparent electrode layer and the pixel electrode layer, and the flexible circuit board is eliminated, which can greatly simplify the system and improve the system stability;

2. Reduce the processing procedures related to the flexible circuit board and reduce the overall cost of the electrophoretic display module;

3. There is no need to set a flexible circuit board bonding area on the circuit board to make the system design more flexible;

4. The flexible circuit board is reduced, and the system of the electrophoretic display module will be easier to design.

As described above, in order to solve the problem of the electrophoretic display module, the present invention proposes a new structure of the electrophoretic display module. The electrophoretic display layer is designed on one side of the circuit substrate, and the control part is designed on the other side of the circuit substrate. A pressure-resistant jig for making a hard material on which an inscribed pattern of all the parts on the circuit substrate is engraved. When the jig is superposed with the processed circuit substrate, it can withstand heavy pressure without damaging the electronic components located on the circuit substrate.

Please refer to FIGS. 1 to 4, which are cross-sectional views showing a manufacturing process of an electrophoretic display module according to an embodiment of the invention.

Referring to FIG. 1 , a hard circuit substrate 206 (eg, a hard printed circuit board) is first provided, and one surface of the circuit substrate 206 is bonded to a pixel electrode layer 202, and the other surface is bonded to at least one driving integrated circuit. Wafer 206a, other required control circuit wafers, passive components or electrical connectors. The pixel electrode layer 202 is composed of a plurality of sub-pixel electrodes 202a, and the integrated circuit chip is directly electrically connected to the sub-pixel electrodes via an inner layer circuit of the circuit substrate 206 (ie, an inner layer copper foil circuit). 202a.

Referring to FIG. 2, the pressing step presses an electrophoretic display layer 201 and a transparent electrode layer 203 onto the pixel electrode layer 202 by a pair of rollers (205a, 205b). Before the pressing step, a pressure preventing fixture 216 is provided, which has a component receiving groove 216a for accommodating the driving integrated circuit wafer 206a, other control circuit chips, passive components or electrical connectors at corresponding positions of the circuit substrate 206. An electronic component that protrudes from the surface of the circuit substrate (not shown on the drawing). The anti-pressure fixture 216 is adhered to the circuit substrate 206 to protect the electronic components that have been processed on the circuit substrate 206, such as the driving integrated circuit wafer 206a, other control circuit chips, passive components or electrical connectors, from being subjected to the roller ( 205a, 205b) direct pressure to cause damage. In other words, the pressure-proof jig 216 is engraved with the engraved pattern of all the parts on the circuit substrate 206 (i.e., the above-described component accommodating groove 216a). When the pressure-proof jig 216 is superposed with the processed circuit substrate 206, it can withstand heavy pressure without damaging the processed electronic parts. The pressure-proof jig 216 has a uniform thickness D, so that the roller (205a, 205b) can uniformly press the electrophoretic display layer 201 and the transparent electrode layer 203 when pressed against the pixel electrode layer 202. The uniform thickness D of the pressure-resistant fixture 216 should be greater than the thickness of the protected electronic component (for example, the thickness of the driver integrated circuit wafer 206a), or at least equal to the thickness of the protected electronic component, to protect the processed circuit substrate 206. Electronic parts are protected from direct pressure by the rollers (205a, 205b). The material of the pressure-proof jig 216 may be a hard material such as a metal material, bakelite or plastic.

Please refer to FIG. 3 , which shows the electrophoretic display module after the pressing step. The electrophoretic display layer 201 and the transparent electrode layer 203 are uniformly adhered to the pixel electrode layer 202 . One end portion 203a of the transparent electrode layer 203 is electrically connected to the circuit substrate 206, so that the driving integrated circuit wafer 206a can be electrically connected to the transparent electrode layer directly through the inner layer circuit of the circuit substrate 206 (ie, the inner layer copper foil circuit). 203. Therefore, the driving integrated circuit wafer 206a is directly electrically connected to the transparent electrode layer 203 and the sub-pixel electrode 202a by using the inner layer circuit of the circuit substrate 206 (ie, the inner copper foil circuit), thereby controlling the display of the electrophoretic display layer 201. Output. The driving integrated circuit chip 206a does not need to be electrically connected to the transparent electrode layer 203 and the sub-pixel electrode 202a via the flexible circuit board, which not only reduces the cost of the flexible circuit board, but also eliminates the need to reserve the flexible circuit board bonding area and reduces the number of flexible circuit board bonding areas. The processing program makes the system design more flexible and the manufacturing cost also has advantages.

Please refer to FIG. 4 , which illustrates the electrophoretic display module 200 after removing the anti-pressure fixture 216 . The driving integrated circuit wafer 206a directly drives the transparent electrode layer 203 and the sub-pixel electrode 202a by the inner layer circuit of the circuit substrate 206 (that is, the inner copper foil circuit), and the flexible circuit board is eliminated, which greatly simplifies the system and improves System stability. The electrophoretic display layer 201 is a liquid polymer layer containing an electronic ink capsule, and the flow direction of the electronic ink is controlled by the transparent electrode layer 203 and the sub-pixel electrode 202a, so that the viewer can see the electrons of the electrophoretic display layer 201 through the transparent electrode layer 203. The image formed by the ink.

It can be seen from the above embodiments of the present invention that the electrophoretic display module and the method of manufacturing the same according to the present invention have at least the following advantages:

1. Driving the integrated circuit directly drives the transparent electrode layer and the pixel electrode layer, and the flexible circuit board is eliminated, which can greatly simplify the system and improve the system stability;

2. Reduce the processing procedures related to the flexible circuit board and reduce the overall cost of the electrophoretic display module;

3. There is no need to set a flexible circuit board bonding area on the circuit board to make the system design more flexible;

4. The flexible circuit board is reduced, and the system of the electrophoretic display module will be easier to design.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and the present invention can be modified and modified without departing from the spirit and scope of the present invention. The scope is subject to the definition of the scope of the patent application attached.

100. . . Electrophoretic display module

101. . . Electrophoretic display layer

102. . . Pixel electrode layer

103. . . Transparent electrode layer

106. . . Circuit substrate

108. . . Drive board

108a. . . Driving integrated circuit chip

110. . . Flexible circuit board

110a. . . Ends

200. . . Electrophoretic display module

201. . . Electrophoretic display layer

202. . . Pixel electrode layer

202a. . . Subpixel electrode

203. . . Transparent electrode layer

203a. . . Ends

205a. . . Wheel

205b. . . Wheel

206. . . Circuit substrate

206a. . . Driving integrated circuit chip

216. . . Pressure-proof fixture

216a. . . Component accommodating slot

The above and other objects, features, advantages and embodiments of the present invention will become more apparent and understood.

1 to 4 are cross-sectional views showing a manufacturing process of an electrophoretic display module in accordance with an embodiment of the present invention.

Figure 5 is a cross-sectional view showing a conventional electrophoretic display module.

200. . . Electrophoretic display module

201. . . Electrophoretic display layer

202. . . Pixel electrode layer

203. . . Transparent electrode layer

203a. . . Ends

206. . . Circuit substrate

206a. . . Driving integrated circuit chip

Claims (7)

An electrophoretic display module comprises at least: a circuit substrate having two opposite surfaces; a pixel electrode layer on one of two opposite surfaces of the circuit substrate; and an electrophoretic display layer on the pixel electrode layer a transparent electrode layer on the electrophoretic display layer; at least one driving integrated circuit wafer on the other surface of the opposite surfaces of the circuit substrate, and the driving integrated circuit wafer directly passes through the circuit substrate The layer circuit is electrically connected to the transparent electrode layer and the pixel electrode layer. The electrophoretic display module of claim 1, wherein the circuit substrate is a rigid circuit substrate. The electrophoretic display module of claim 1, wherein the circuit substrate is a hard printed circuit board. A method for manufacturing an electrophoretic display module, comprising: bonding a pixel electrode layer to a surface of a circuit substrate; bonding at least one driving integrated circuit chip to another opposite surface of the circuit substrate, and driving the driving The integrated circuit chip is directly connected to the pixel electrode layer through an inner layer circuit of the circuit substrate; and a pressure preventing fixture is bonded to another opposite surface of the circuit substrate, wherein the pressure preventing fixture comprises at least one component The accommodating groove is configured to receive the driving integrated circuit chip; an electrophoretic display layer and a transparent electrode are laminated on the pixel electrode layer by a pair of rollers, and the driving integrated circuit chip is directly passed through the circuit substrate The inner layer circuit is electrically connected to the transparent electrode layer and the pixel electrode layer; and the pressure preventing fixture is removed. The manufacturing method according to claim 4, wherein the pressure-proof jig has a uniform thickness. The manufacturing method according to claim 5, wherein the pressure-resistant jig has a uniform thickness greater than or equal to a thickness of the driving integrated circuit chip. The manufacturing method according to claim 4, wherein the material of the pressure-proof jig comprises a metal material, bakelite or plastic.