JP2006301135A - Liquid crystal display element and flexible printed wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display element of which the costs are reduced and production efficiency is enhanced by eliminating a material and a step only for protecting test signal inputting terminals. <P>SOLUTION: The liquid crystal display element 10 is provided with: an LCD panel 11 having the test signal inputting terminals 18 for inputting a test signal and a regular signal inputting terminals 19 for inputting a regular signal; and a flexible printed wiring board 12 connected to the regular signal inputting terminals 19. The test signal inputting terminals 18 are covered by the flexible printed wiring board 12, and the test signal inputting terminals 18 and the flexible printed wiring board 19 are made to adhere to each other by an anisotropic conductive film 20. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  A liquid crystal display device comprising a test signal input terminal for inputting a test signal and an LCD panel having a normal signal input terminal for inputting a normal signal; and a flexible printed wiring board connected to the normal signal input terminal; And a flexible printed wiring board thereof.

  In recent years, a liquid crystal display element having a liquid crystal driving circuit built in an LCD panel typified by low-temperature polysilicon, a so-called system liquid crystal, has been widely used as a display unit of a cellular phone or the like. The system liquid crystal panel incorporates a logic circuit including a gate circuit in addition to the pixel transistor.

  In this system liquid crystal manufacturing process, usually, after the LCD panel is completed, an LCD source driver circuit driver LSI chip and a flexible printed circuit board (FPC) for inputting interface signals are mounted on a glass substrate.

  Here, usually, before the mounting of components after completion of the LCD panel, an electric signal is input to the LCD panel alone to perform a display inspection. As a result, it is possible to prevent the defective LCD panel from flowing to a subsequent process, so that the mounted parts are not wasted.

  In order to perform the display inspection, the LCD panel is provided with a test signal input terminal for inputting a test signal, in addition to a normal signal input terminal for inputting a normal signal to which the FPC is connected. Since this test signal input terminal is not used after the product is completed, it is sealed and insulated and protected by resin after the display inspection is completed.

  FIG. 3 is a plan view of a conventional liquid crystal display element 100, and FIG. 4 is a sectional view taken along line BB of FIG. The liquid crystal display element 100 is an element in a state where components such as the FPC 101 are mounted on the LCD panel 11. The test signal input terminal 18 is covered with a resin 102 such as TUFFY, and the normal signal input terminal 119 is covered with an FPC 101. The FPC 101 is pressure-bonded using the anisotropic conductive film 20. The FPC 101 includes a conductor wiring 101 a and a resin 101 b, and the conductor wiring 101 a is connected to the normal signal input terminal 19. The reason for sealing the test signal input terminal 18 with the resin 102 is to prevent electrostatic breakdown. When static electricity enters from the test signal input terminal 18, an insulating film breakage or the like inside the liquid crystal display element 100 occurs, resulting in a malfunction of the element. Since the system liquid crystal incorporates a liquid crystal driving circuit such as a low-temperature polysilicon semiconductor in the LCD panel 11, countermeasures against static electricity are important.

From the viewpoint of preventing device defects, for example, there is one for the purpose of preventing corrosion of transparent electrodes of a simple matrix LCD panel (see Patent Document 1).
JP 61-167924 A

  However, in the liquid crystal display element 100 as shown in FIGS. 3 and 4, the process of sealing the test signal input terminal 18 with the resin 102 cannot be omitted. Further, when the method of Patent Document 1 is applied to sealing of the test signal input terminal 18, the test signal input terminal 18 is covered with a protective film, and a process of forming the protective film is required. Therefore, conventionally, extra materials and processes are required to protect the test signal input terminal 18 which is not necessary after commercialization.

  An object of the present invention is to provide a liquid crystal display element that eliminates materials and processes only for protecting a test signal input terminal, reduces costs, and improves production efficiency. Another object of the present invention is to provide a flexible printed wiring board mounted on the liquid crystal display element.

  In order to achieve the above object, a liquid crystal display element of the present invention is characterized in that a test signal input terminal provided on an LCD panel is covered with a flexible printed wiring board connected to a regular signal input terminal. . The flexible printed wiring board of the present invention is characterized in that it is connected to a normal signal input terminal provided on the LCD panel and covers a test signal input terminal provided on the LCD panel.

  According to these configurations, the test signal input terminal is insulated and protected by the flexible printed wiring board, and the entry of static electricity can be prevented.

  In the liquid crystal display element or the flexible printed wiring board, the test signal input terminal and the flexible printed wiring board are bonded with an anisotropic conductive film.

  According to this configuration, after a test signal is input to the test signal input terminal and a display inspection of the LCD panel is performed, a flexible printed wiring board is crimped to a good LCD panel using an anisotropic conductive film. The signal input terminal and the test signal input terminal can be bonded at a time.

  In the liquid crystal display element described above, it is desirable that the test signal input terminal and the regular signal input terminal are arranged in order from the liquid crystal material in the LCD panel.

  Usually, the flexible printed wiring board is connected from the outside of the LCD panel, so that the conductor wiring of the flexible printed wiring board does not contact the test signal input terminal.

  According to the present invention, since the test signal input terminal is insulated and protected by the flexible printed wiring board together with the regular signal input terminal, a material and a process only for protecting the test signal input terminal are not required, thereby reducing the cost and improving the production efficiency. Can be made.

  FIG. 1 is a plan view of a liquid crystal display element, and FIG. 2 is a cross-sectional view taken along line AA of FIG. The liquid crystal display element 10 includes an LCD panel 11, a flexible printed wiring board (FPC) 12, and an LCD driver 13.

  The LCD panel 11 includes two glass substrates 14 and 15, a sealing material 16 that bonds the peripheral portions of both glass substrates 14 and 15, and a liquid crystal that fills a space surrounded by the glass substrates 14 and 15 and the sealing material 16. A material 17, a test signal input terminal 18 provided on the glass substrate 15, and a regular signal input terminal 19 provided on the glass substrate 15 are provided.

  The test signal input terminal 18 is a terminal for inputting a test signal to the LCD panel 11 and performing a display inspection before mounting components (FPC 12, LCD driver 13, etc.) after the LCD panel 11 is completed. The test signal input terminal 18 is not used after the product is completed. On the other hand, the regular signal input terminal 19 is a terminal for inputting a regular signal to which the FPC 12 is connected.

  The FPC 12 includes a conductor wiring 12a and a resin 12b, and is bonded to the glass substrate through the anisotropic conductive film 20. A soft resin that can be easily bent is used for the resin 12b. The FPC 12 covers the test signal input terminal 18 and the normal signal input terminal 19, the conductor wiring 12 a is connected to the normal signal input terminal 19, and the resin 12 b is bonded to the test signal input terminal 18 through the anisotropic conductive film 20. . Thereby, the test signal input terminal 18 is insulated and protected. Note that another adhesive may be used instead of the anisotropic conductive film 20.

  In FIG. 1, the vicinity of the connecting portion of the FPC 12 is formed in a U-shape. Thus, the FPC 12 can be mounted while avoiding the LCD driver 13 while covering the test signal input terminal 18 and the normal signal input terminal 19. The FPC 12 can be manufactured easily and with little cost increase by preparing an extension of the resin portion of the conventional FPC and cutting off the portion overlapping the LCD driver 13.

  In addition, if the arrangement of the test signal input terminal 18 and the regular signal input terminal 19 is changed, the shape of the FPC 12 can be changed accordingly. Here, it is desirable to arrange the test signal input terminal 18 and the regular signal input terminal 19 in order from the liquid crystal material. Usually, the FPC 12 is connected from the outside of the LCD panel 11, so that the conductor wiring 12 a of the FPC 12 does not contact the test signal input terminal 18. On the other hand, if the normal signal input terminal 19 and the test signal input terminal 18 are arranged in the order closest to the liquid crystal material, it is difficult to route the conductor wiring 12 a so as not to contact the test signal input terminal 18.

  The LCD driver 13 includes an LCD source drive circuit driver LSI chip, and is mounted on the glass substrate 15 by a chip-on-glass method.

  Next, the production procedure of the liquid crystal display element 10 will be described. After the LCD panel 11 is manufactured, first, a test signal is input to the test signal input terminal 18 to perform display inspection of the LCD panel 11 and remove defective products from the production line. As a result, it is possible to prevent the defective LCD panel from flowing to a subsequent process, so that the mounted parts are not wasted. Subsequently, the FPC 12 is pressure-bonded to the good LCD panel 11 using the anisotropic conductive film 20, and various components (LCD driver 13 and the like) are also mounted. By using the anisotropic conductive film 20, the normal signal input terminal 19 and the test signal input terminal 18 can be bonded at a time.

  When the FPC 12 is pressure-bonded by the above-described process, the entry of static electricity from the test signal input terminal 18 and the regular signal input terminal 19 can be prevented thereafter. Since the system liquid crystal incorporates a liquid crystal driving circuit such as a low-temperature polysilicon semiconductor in the LCD, countermeasures against static electricity are important. If static electricity enters from the test signal input terminal 18 or the regular signal input terminal 19, the insulation film inside the liquid crystal display element 10 is broken, and the element is defective.

  The present invention can be applied to a system liquid crystal in which a liquid crystal driving circuit is built in an LCD panel typified by low-temperature polysilicon, and the liquid crystal display element of the present invention can be used as a display unit of a mobile phone or the like.

It is a top view of the liquid crystal display element of this invention. It is the sectional view on the AA line of FIG. It is a top view of the conventional liquid crystal display element. FIG. 4 is a sectional view taken along line BB in FIG. 3.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Liquid crystal display element 11 LCD panel 12 Flexible printed wiring board 17 Liquid crystal material 18 Test signal input terminal 19 Regular signal input terminal 20 Anisotropic conductive film

Claims (5)

A liquid crystal display device comprising: an LCD panel having a test signal input terminal for inputting a test signal and a normal signal input terminal for inputting a normal signal; and a flexible printed wiring board connected to the normal signal input terminal In
The liquid crystal display element, wherein the test signal input terminal is covered with the flexible printed wiring board.   The liquid crystal display element according to claim 1, wherein the test signal input terminal and the flexible printed wiring board are bonded with an anisotropic conductive film.   3. The liquid crystal display element according to claim 1, wherein a test signal input terminal and a regular signal input terminal are arranged in the order close to the liquid crystal material in the LCD panel. In a flexible printed wiring board connected to an LCD panel having a test signal input terminal for inputting a test signal and a normal signal input terminal for inputting a normal signal,
A flexible printed wiring board connected to the regular signal input terminal and covering the test signal input terminal.   The flexible printed wiring board according to claim 4, wherein the flexible printed wiring board is bonded to the test signal input terminal with an anisotropic conductive film.

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