JP2008145753A - Display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain high connection reliability by easily and surely connecting circuit boards in a display device to which a plurality of circuit boards are connected. <P>SOLUTION: The display device is provided with: an insulating substrate 1 on which a display area is formed; a first circuit board 6 connected to a portion other than the display area on the insulating substrate 1 in order to supply a signal in the display area; a planar light source device arranged on the side opposite to the face on which the display area is formed in the insulating substrate 1 to supply light to the display area; and a second circuit board 10 connected to the planar light source device to supply power. In the first circuit board 6 and the second circuit board 10, an end part of the second circuit board 10 is inserted into and abutted on a hole 15 or a notch formed on the first circuit board 6 to position the second circuit board 10. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a display device having a printed circuit board connected to a terminal on an insulating substrate having a display area, and connecting the printed circuit board to another printed circuit board.

The liquid crystal display device is configured by arranging a liquid crystal panel on a light emitting surface of a planar light source device. A liquid crystal panel is formed by two substrates facing each other with a predetermined gap, adhered by a sealing material at the periphery of the substrate, and encapsulating a liquid crystal layer between the two substrates. The polarizing plate which has is stuck. A printed wiring board (Flexible Printed Circuit: hereinafter referred to as FPC) having flexibility and a driving IC is provided on an electrode terminal portion of the liquid crystal panel via an anisotropic conductive film (hereinafter referred to as ACF). Installed. A signal and power from a printed circuit board (hereinafter referred to as PWB) are supplied to the input electrode terminal portion of the FPC. In addition, the planar light source device serving as the light source transmits light emitted from the LED of the point light source mounted on the FPC to the light emitting surface by propagating through the light guide plate and leaks to the back surface of the light guide plate. The reflected light is reflected by the reflecting sheet and returned to the light guide plate. On the light emitting surface side of the light guide plate, the light is efficiently transmitted to the light emitting surface by the diffusion sheet and the lens sheet disposed on the surface side (light emitting surface side) of the light guide plate. Spreads light evenly. The FPC connected to the planar light source device is connected to a terminal or connector on the FPC connected to the insulating substrate constituting the PWB or liquid crystal panel, and supplied with power. In particular, when connecting to a terminal on the FPC, the FPC is positioned by checking the positioning marks or terminals with a camera or the like while aligning the positions, or at least two positions for positioning. The hole or notch is positioned with a pin or the like for connection.

As another conventional technique, in an FPC connected to a conductive portion of a display panel on which an IC chip is mounted, the tip shape on the connection side of the FPC is a reference surface that is composed of at least a part of each of the three outer surfaces of the IC chip. The positioning part is in a shape having an abutting part that is in contact with the IC chip, and the positioning part is brought into contact with the reference surface of the IC chip and positioned on the display panel (for example, see Patent Document 1).

JP 2006-78790 A

  However, in the above-described FPC connection method of the liquid crystal display device, equipment costs such as a tool for checking the positioning state of the positioning marks or terminals and tools such as positioning pins are generated. Further, since it is necessary to connect the FPC while holding it after positioning confirmation, it is necessary to reduce costs and improve workability such as occurrence of misalignment during connection and increase in work time.

  Further, in the above-described prior art of Patent Document 1, there is no disclosure regarding the connection method between the FPC connected to the terminal on the insulating substrate and the other FPC, and the connection to the terminal on the insulating substrate is not disclosed. Therefore, it is difficult to easily and reliably connect the FPC to other FPCs.

The present invention has been made in view of such problems, and in a display device for connecting an FPC connected to a terminal on an insulating substrate and another FPC, it is possible to easily and reliably connect the display device. The purpose is to obtain high connection reliability.

The present invention provides an insulating substrate on which a display area is formed, a first circuit board connected to the display area outside the display area for supplying a signal to the display area, and the display area. A planar light source device disposed on a side opposite to the surface on which the display area of the insulating substrate is formed so as to supply light, and a second circuit substrate connected to the planar light source device and supplying power. In the display device provided, the first circuit board and the second circuit board are obtained by inserting an end of the second circuit board into a hole or a notch formed in the first circuit board. The second circuit board is positioned by contacting the second circuit board.

  According to the present invention, in a display device for connecting an FPC connected to a terminal on an insulating substrate and another FPC, a display device with high connection reliability can be obtained by making an easy and reliable connection. Can do.

Embodiment 1 FIG.
A first embodiment of the present invention will be described with reference to FIGS. 1 is an overall plan view of a display device according to Embodiment 1 of the present invention, and FIG. 2 is a cross-sectional view from the direction AA in FIG.

In FIG. 1 and FIG. 2, an insulating substrate 1 on which a display area is formed and a counter substrate 2 are bonded together, and polarizing plates 3 and 4 are respectively bonded to the outer surface side to constitute a liquid crystal panel. A driving IC chip 5 and a first circuit board 6 (FPC in FIGS. 1 and 2) are ACFs on terminal portions on the insulating substrate 1 (the lower portion of the paper on the insulating substrate 1 in FIG. 1). It connects through resin, such as. Further, on the side opposite to the surface on which the display area of the insulating substrate 1 is formed, a planar light source device that includes a light source 7 such as an LED and a light guide plate 8 and supplies light to the display area is disposed. ing. The planar light source device is supported by a resin frame 9, and the resin frame 9 also supports the liquid crystal panel. In order to supply power to the light source of the planar light source device, a second circuit board 10 (FPC in FIGS. 1 and 2) is connected to the planar light source device. The first circuit board 6 and the second circuit board 10 are disposed on the same side of the liquid crystal panel (in FIG. 1, the side on which the driving IC chip 5 is mounted). Various optical sheets 11 such as a diffusion sheet and a lens sheet are disposed between the light guide plate 8 and the liquid crystal panel.

The power supply to the planar light source device is performed using the second circuit board 10 as described above, but the end of the second circuit board opposite to the end connected to the planar light source device. Solder after positioning so that the second connection terminal 12 formed on the other end (hereinafter referred to as the other end) is not displaced from the first connection terminal 13 provided on the first circuit board 6. Alternatively, they are connected via a connection material such as ACF. The first connection terminal 13 is connected to the third connection terminal 14 by a pattern on the first circuit board 6, and power is supplied to the third connection terminal 14 from an external PWB or the like. Usually, in the liquid crystal display device shown in the present embodiment, the first circuit board 6 is folded and fixed to the back surface side of the planar light source device. In the vicinity of the first connection terminal 12 in the first circuit board 6, a notch or a hole (hole 15 in FIG. 1) is provided, and a predetermined circuit is provided at the other end of the second circuit board 10. A step 16 formed by cutting out the side of the tip is provided so as to be wider than the hole 12 from the position.

In the present embodiment, the other end of the second circuit board 10 is inserted into a notch or hole 15 formed in the first circuit board 6, and after being inserted by a certain amount, the step 16 further increases. A state in which the second circuit board 10 cannot be inserted (the stepped portion 16 and the first circuit board 6 are in contact with each other) and the second circuit board 10 is pressed toward the other end by using the stepped portion 16 as a fulcrum due to its own deflection. In this state, the vertical positioning in FIG. 1 is performed. 1 is performed by inserting the tip of the other end of the second circuit board 10 into a notch or hole in the first circuit board 6, and the liquid crystal panel is made of resin. It is also implemented by being incorporated in the frame 9 and further prevents displacement in the rotational direction.

As described above, according to the present embodiment, the second connection terminal 12 of the second circuit board 10 is inserted by inserting the tip of the other end of the second circuit board 10 into the notch or the hole of the first circuit board 6. The first circuit board 6 can be easily and reliably positioned on the first connection terminal 13 in FIG. With this configuration, it is possible to easily and surely connect the circuit boards to each other or perform connection such as ACF without positioning with an external positioning pin or the like.

Embodiment 2. FIG.
A second embodiment of the present invention will be described with reference to FIGS. FIG. 3 is an overall plan view of a display device according to Embodiment 2 of the present invention, and FIG. 4 is an overall plan view of another display device according to Embodiment 2 of the present invention. 3 and 4, the same components as those in FIGS. 1 and 2 are denoted by the same reference numerals, and differences from the first embodiment will be described.

In the first embodiment, the other end of the second circuit board 4 has a step formed by notching the side of the tip so that the width is wider than the hole from a predetermined position. First, in FIG. 3, the shape of the tip of the other end of the second circuit board 10 is made into a shape having two notches 17, and the tip is separated into a total of three places: a center portion and two side edges. By adopting the shape, for example, two side end portions are inserted into notches or holes (holes 15 in FIG. 3) formed at corresponding positions on the first circuit board, as in the first embodiment. Thus, positioning in the vertical direction of the paper surface is performed. Positioning in the horizontal direction on the paper surface is performed by inserting two side end portions of the tip portion of the second circuit board into the notches or holes of the first circuit board, as in the first embodiment. In addition, it is also implemented by incorporating the liquid crystal panel into the resin frame, and further misalignment in the rotation direction is prevented.

  Next, in FIG. 4, as in the first embodiment, the tip of the second circuit board 10 is inserted into the hole 15 of the first circuit board 6 and positioned, but the power is supplied from the external PWB 18. Also at the tip of the third connection terminal 14 on the first circuit board 6 to which the first and the like are supplied, the step portion 19 is formed by cutting out the side as shown in FIG. The circuit board 6 is positioned on the PWB 18. A cutout or a hole (hole 20 in FIG. 4) is formed at a position corresponding to the tip of the third connection terminal 14 in the PWB 18.

With the configuration as described above, it is possible to achieve the same effect as that of the first embodiment. Further, in FIG. 4, the FPC connected to the terminal on the insulating substrate and the other FPC In addition to the connection, it is possible to easily and reliably connect to an external PWB connected to the FPC. Note that the PWB in this embodiment may be formed on a flexible film or may be formed on a rigid substrate. Further, FIG. 4 shows an example in which the second circuit board is connected to the first circuit board. However, if necessary, the second circuit board can be connected to the PWB as in the first circuit board. You may connect. Needless to say, the connection configuration between the first or second circuit board and the external PWB may be combined with the configurations of the other embodiments in this specification.

Embodiment 3 FIG.
A third embodiment of the present invention will be described with reference to FIGS. FIG. 5 is an overall plan view of the display device according to Embodiment 3 of the present invention, and FIG. 6 is a partially enlarged view of another display device according to Embodiment 3 of the present invention. 5 and 6, the same components as those in FIGS. 1 to 4 are denoted by the same reference numerals, and differences from the first and second embodiments will be described.

  In FIG. 5, the configuration is almost the same as that of FIG. 1 of the first embodiment, except that the second circuit board 10 is inserted into the hole 15 of the first circuit board 6 when the second circuit board 10 is inserted. In order to reduce the thickness of the overlapping portion of the circuit board in the vicinity of the insertion portion, the thickness of the overlapping portion is formed by forming a step in the X portion of the first circuit board 6 in FIG. 5 or by reducing the thickness. It is possible to suppress the increase of.

  Next, FIGS. 6A and 6B are enlarged views of a portion in which the tip of the second circuit board 10 is inserted into the hole 15 of the first circuit board 6. First, (a As shown in the figure, at the tip of the other end of the second circuit board 10, a portion to be inserted into the hole 15 of the first circuit board (in FIG. 6, a notch is formed on the side of the tip. A notch or hole (hole 21 in FIG. 6) is formed in the portion), and when the operator pulls it lightly with a fingertip, the tip portion (detaching portion 22 in FIG. 6) can be easily separated. Leave it in a certain state. After that, as shown in FIG. 5B, the other end of the second circuit board is inserted into the hole of the first circuit board, and the second connection terminal 12 of the second circuit board and the first circuit board are connected. After connecting the first connection terminal, the separation part 22 is pulled and separated by the operator's fingertip or the like, whereby an increase in the thickness of the circuit board due to the overlapping part of the circuit boards can be suppressed.

With the configuration as described above, in addition to the same effects as those of the first and second embodiments, an increase in thickness due to overlapping of circuit boards can be suppressed.

In the first to third embodiments, a display device using liquid crystal has been described as an example. However, the present invention is not limited thereto, and the display device using an electroluminescence (EL) element or the like is used. The present invention can be applied to any display device that connects an FPC connected to a terminal and another FPC.

1 is an overall plan view of a display device according to Embodiment 1 of the present invention. It is sectional drawing from the AA direction in FIG. It is a whole top view of the display apparatus in Embodiment 2 of the present invention. It is a whole top view of the other display apparatus in Embodiment 2 of this invention. It is a whole top view of the display apparatus in Embodiment 3 of the present invention. It is the elements on larger scale of the other display apparatus in Embodiment 3 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Insulating board | substrate, 2 Opposite board | substrate, 3 Polarizing plate, 4 Polarizing plate, 5 Driving IC, 6 1st circuit board, 7 Light source, 8 Light guide plate, 9 Resin frame, 10 2nd circuit board, 11 Optical sheet , 12 2nd connection terminal, 13 1st connection terminal, 14 3rd connection terminal, 15 holes, 16 stepped part, 17 notch, 18 PWB, 19 stepped part, 20 hole, 21 hole, 22 cut off part

Claims (6)

An insulating substrate having a display area formed thereon;
A first circuit board connected outside the display area on the insulating substrate to supply a signal to the display area;
A planar light source device disposed on the side opposite to the surface on which the display area of the insulating substrate is formed to supply light to the display area;
A second circuit board connected to the planar light source device for supplying power;
A display device comprising:
The first circuit board and the second circuit board are formed by inserting and abutting the other end of the second circuit board into a hole or notch formed in the first circuit board. The display device is characterized in that the second circuit board is positioned. The display device according to claim 1, wherein the other end portion of the second circuit board has a stepped portion formed by cutting out a side. The display device according to claim 1, wherein the first and second circuit boards are made of a flexible substrate. The other end portion of the second circuit board is formed so that the thickness of the first circuit board is thinner than the other part in the portion inserted into the hole or notch of the first circuit board. The display device according to claim 1. 5. The display device according to claim 1, wherein the other end portion of the second circuit board is detachable after being inserted into a hole or notch of the first circuit board. . A third circuit board for supplying power to the first circuit board, wherein the first circuit board and the third circuit board are holes or notches formed in the third circuit board; The display device according to claim 1, wherein the first circuit board is positioned by inserting and abutting an end of the first circuit board.

Images