JPH11212484A - Display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To mount a panel and a circuit board which have narrow pitches and high definition easily to a reduced size by equalizing the electrodes of a display panel and the electrodes for display panel driving in array pitch. SOLUTION: An elastic connector 6 which has conductive silicone rubber and insulating silicone rubber stacked is arranged on the reverse surface side of a display panel electrode 3. The elastic connector 6 is pressed and clamped between the circuit board 7 and display panel 1 by fixing positioning pins 10 and the display panel electrode 3 and circuit board 8 for panel driving are connected. The number of panel scanning electrodes or panel data signal electrodes of the display panel electrode 3 is set several electrodes larger than the number of the panel scanning electrodes or panel data signal electrodes of the circuit board 8 for panel driving. Therefore, some of ends of the display panel electrode 3 are not connected and although dots are present at part of the display panel 1, there is no practical problem.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for connecting a display panel to a circuit board having a driving circuit. Further, the present invention relates to a connection method using an elastic connector.

[0002]

2. Description of the Related Art In a display device of a simple matrix type, as a method of connecting a display panel and a circuit board arranged on the lower surface side thereof, an interconnector such as an elastic connector is arranged and connected therebetween, and these are all connected. Is known in the art (for example, Japanese Utility Model Laid-Open No. 6-82596). When a high-definition panel is used and a connection at a narrow pitch is required, a method of connecting a heat seal type connector or a flexible substrate with an anisotropic conductive film is used.

[0003]

However, in the connection method using the above-described elastic connector, even if various measures are taken for alignment, it is possible to eliminate variations in dimensions of panels and circuit boards in manufacturing. It is not possible, and connection is possible only with an electrode pitch higher than these dimensional accuracy, and there is a limit in handling electrodes with a narrow pitch. In a general display device, the electrode pitch is limited to about 0.5 mm. With a narrower pitch, it is difficult to connect the display panel electrode and the circuit board electrode one-to-one, and a pitch shift occurs. The problem arises.

[0004] On the other hand, a method of connecting with a heat seal or a flexible substrate or the like can cope with connection of a narrow pitch electrode, but it complicates the manufacturing process, and in particular, the electrode is formed on two or more sides of the panel. The mounting process in the case of providing is complicated. In addition, since the heat seal or the flexible substrate comes out of the panel, the planar size becomes large, and it has a drawback that it is difficult to apply particularly to a small display device.

SUMMARY OF THE INVENTION In view of these problems, an object of the present invention is to provide a display device capable of mounting a narrow-pitch, high-definition panel and a circuit board simply and in a small size. .

[0006]

In order to achieve the above object, a display device of the present invention has an elastic connector between a matrix type display panel and a circuit board having a display driver of the display panel. In a display device arranged and electrically connecting the electrodes of the display panel and the electrodes for driving the display panel on the circuit board, the electrodes of the display panel and the electrodes for driving the display panel of the circuit board are electrically connected. The arrangement pitch is the same, and the number of electrodes of the display panel is different from the number of electrodes for driving the display panel of the circuit board.

That is, the electrodes for driving the display panel on the circuit board are composed of scanning signal electrodes and data signal electrodes, and the electrodes of the display panel are composed of panel scanning signal electrodes and panel data signal electrodes. The number of the scanning signal electrodes is n, the number of the data signal electrodes is m,
When at least one of i and j is a natural number of 1 or more, the display panel has liquid crystal cells arranged in a matrix of n + i rows and m + j columns, and n + i panel scan signal electrodes and m + j panel data signal electrodes. It is characterized by having.

Alternatively, the electrodes of the display panel are composed of panel scanning signal electrodes and panel data signal electrodes, and the electrodes for driving the display panel on the circuit board are composed of scanning signal electrodes and data signal electrodes. When the number of electrodes is n, the number of panel data signal electrodes is m, and at least one of i and j is a natural number of 1 or more, the circuit board includes n + i scan signal electrodes and m + j data signal electrodes. A connection state in which the display driver detects a connection state between an electrode of the display panel and an electrode for driving the display panel of the circuit board after connecting the display panel and the circuit board with the elastic connector. The detection circuit and the electrodes used to drive the display panel are placed on the circuit board from the electrodes for driving the display panel. It is characterized in that it has an electrode selection circuit for the electrodes as many selection of the display panel.

An elastic connector is arranged between a matrix type display panel and a circuit board having a display driver of the display panel, and an electrode of the display panel is provided on the circuit board to drive the display panel. In a display device for electrically connecting electrodes, the electrodes for driving the display panel on the circuit board are composed of scanning signal electrodes and data signal electrodes, and the electrodes of the display panel are panel scanning signal electrodes and panel data signal electrodes. One or both ends of one or both of the scanning signal electrodes and the data signal electrodes on the circuit board in the electrode arrangement direction have electrodes to which a non-lighting signal of one or more of the display panels is constantly input. The display panel may be configured such that the number of the scanning signal electrodes on the circuit board is n, and the number of the data signal electrodes is m, i, and j. If at least one of them is a natural number of 1 or more, the liquid crystal cells are arranged in a matrix of n + i rows and m + j columns, and have n + i panel scan signal electrodes and m + j panel data signal electrodes. An electrode to which a non-lighting signal of the display panel is always input and the panel scanning signal electrode or the panel data signal electrode are electrically connected at one or more locations by the elastic connector. .

According to the above structure of the present invention, the number of electrodes for connecting the display panel and the circuit board is different, and the structure is such that spare electrodes are provided on the display side or the circuit side. , The allowable deviation amount can be set to be larger than the electrode pitch. Therefore, connection at a narrow pitch becomes possible.

That is, when the display panel and the substrate are connected by the elastic connector, even if a deviation larger than the pitch dimension occurs due to a variation in dimensional accuracy, etc.
The panel moves in parallel with the displacement, and the panel and the circuit board are connected by another electrode. Alternatively, the state is a state where all conduction is not established or a state where a short circuit occurs. In this case, it can be easily corrected by shifting the elastic connector a little and mounting it again. Therefore, connection at a narrow pitch can be easily performed.

If the display panel has a spare display area and the number of electrodes on the display panel is larger than the number of electrodes on the circuit board, the spare part of the display panel corresponding to the surplus electrodes that are not connected does not operate, but requires special steps and operations. , The allowable dimension of the alignment can be set to be equal to or larger than the electrode pitch, and connection at a narrow pitch is possible.

On the other hand, when the number of electrodes on the circuit board is larger than that on the display panel, after the connection with the elastic connector, the electrodes not connected on the circuit board are detected, and the display panel is driven starting from the connected electrodes. By selecting and setting the electrodes, connection at a narrow pitch becomes possible.

Also, by providing an electrode on the circuit board to which a non-lighting signal is always input and connecting to an auxiliary display area of the display panel, a stable non-lighting state can be maintained at all times. Can be eliminated.

[0015]

Embodiments of the present invention will be described with reference to the drawings.

(First Embodiment) FIG. 1 is a sectional view of a module of a display device according to a first embodiment of the present invention. The display panel 1 of the dot matrix type is supported and arranged by a step provided inside the panel frame 2.
A zebra type elastic connector 6 formed by laminating a conductive silicone rubber 4 and an insulating silicone rubber 5 is disposed on one or more sides of the lower surface on which the display panel electrode 3 is formed. A circuit board 7 is arranged and connected to a circuit board electrode 8 for driving a panel. In some cases, a silicone rubber or elastic connector 6 may be arranged on another side where the display panel electrode 3 (not shown) is not formed to hold the display panel.

The display panel electrode 3 has the same structure whether it is a panel scanning electrode or a panel data signal electrode.

The panel frame 2 is formed with positioning pins 10 which also serve as screws for fastening the panel frame 2 and the circuit frame 9. The panel frame 2 is positioned. Next, the circuit frame 9 is screwed and fixed to the lower side of the circuit board 7 with the positioning pins 10. As a result, the elastic connector 6 is pressed and held between the circuit board 7 and the display panel 1, and the display panel electrode 3 and the panel driving circuit board electrode 8 are connected. FIG. 2 is a sectional view of the module of the display device viewed from another angle. Here, the circuit board electrode 8 indicates a scanning signal electrode or a data signal electrode corresponding to the display panel 1. Next, details of connection between the display panel 1 and the circuit board 7 will be described.

The display panel electrodes 3 correspond to the number of dots of the display panel 1 and include two types of panel scan electrodes and panel data signal electrodes, and are formed on the lower surface of the display panel 1 so as to face the circuit board 7. The circuit board electrode 8 for driving the panel is composed of two types, a scanning electrode and a data signal electrode, and is formed on the upper surface so as to face the display panel 1. The panel driving circuit board electrodes 8 and the display panel electrodes 3 are formed at the same pitch. Further, it is desirable that the sum of the respective electrode widths is set to be equal to or smaller than the pitch dimension.
Then, the circuit board 7 and the display panel 1 are connected by disposing the elastic connector 6 therebetween. FIG. 3 is a sectional view showing a connection state between the display panel 1 and the circuit board 7.
(A). Here, even if the positional relationship between the display panel 1 and the circuit board 7 is shifted more than the electrode pitch dimension in the horizontal direction, the circuit board electrode 8 for driving the panel and the display panel electrode 3
Are connected one-to-one, or all electrodes are not connected at all or all are short-circuited.
However, the occurrence rate of this incorrectly connected state is very low, and even if it occurs, it can be easily corrected by reassembly.

Further, when the number of scanning signal electrodes on the circuit board 7 is n and the number of data signal electrodes on the circuit board 7 is m, n
Liquid crystal cells are arranged in a matrix in rows m columns or more, and as shown in FIG. 1, the number of panel scanning signal electrodes or panel data signal electrodes of the display panel electrodes 3 also corresponds to the corresponding circuit board electrodes for driving the panel. The number is set to be several more than the number of eight scanning signal electrodes or data signal electrodes. Therefore, when the display panel 1 and the circuit board 7 are connected via the elastic connector 6, some of the ends of the display panel electrodes 3 are not connected, and some of the ends of the display panel 1 are not connected. Despite the presence of the dots, there are portions that are not included in the display, but this is not a practical problem. As described above, the spare display panel electrode 3 allows the allowable displacement during mounting to be greater than the pitch dimension. Therefore, connection at a narrower pitch than in the related art becomes possible.
In addition, the displacement amount at the time of mounting is about 0.5 mm or less, which is a level that does not cause any problem in practical use.

The above embodiment is not limited to the above. For example, as the elastic connector 6, an anisotropic conductive connector in which a metal wire is arranged in an insulating silicone rubber other than a zebra type is used. Is also good.

(Second Embodiment) FIG. 4 is a block diagram showing a second embodiment of the display device of the present invention. Display panel 1
Has liquid crystal cells arranged in a matrix, and has m liquid crystal cells in the X-axis direction and n liquid crystal cells in the Y-axis direction. Signal line electrodes connected to one row of liquid crystal cells are arranged on one side in the X-axis direction from data signal electrodes S1 to Sm, and scanning signal electrodes connected to one row of liquid crystal cells are arranged from C1 to Cn on one side in the Y-axis direction. ,
It is connected to the circuit board 7 by an elastic connector. The number of electrodes of the circuit board 7 is X from the number of electrodes of the display panel 1.
There are many in the axial direction and the Y axis direction. A display driver 12 is formed on the circuit board 7. The display driver 12 is usually formed of an IC or the like, and a plurality of circuits are integrated.

FIG. 5 is a block diagram showing a circuit configuration of the display driver 12 shown in FIG. The liquid crystal drive circuit 51 is connected to the data signal electrodes S1 to Sm of the display panel 1 from SB1 to SBm + 2, and the scan signal electrodes C1 to Cn.
Are connected, and data lines from CB1 to CBn + 2 are prepared. At this time, it is assumed that the number of electrodes of the circuit board 7, that is, the number of the liquid crystal drive circuits 51 is larger by two in each of the X-axis direction and the Y-axis direction than the number of electrodes of the display panel 1. The liquid crystal driving circuit 51 generates a liquid crystal driving voltage based on the timing generated by the display timing generating circuit 52 and the potential required for liquid crystal display by the power supply circuit 53, and displays the liquid crystal. The state detection circuit 54 includes electrodes SB1, SBm + 2, C
B1 and CBn + 2, and detects whether each electrode is connected to the electrode of the display panel 1. The electrode selection circuit 55 specifies a range of electrodes from which the liquid crystal drive circuit 51 outputs a liquid crystal drive voltage based on the connection state of each electrode detected by the state detection circuit 54.

FIG. 6 shows that the state detection circuit 54 is connected to each electrode SB1,
It is a table | surface which shows determination at the time of detecting the connection state of SBm + 2, CB1, CBn + 2. FIG. 6A shows the determination of the places where S1 to Sm of the display panel electrodes 3 are placed on the circuit board electrodes based on the connection state of the data signal electrodes SB1 and SBm + 2. FIG. 3 is a sectional view showing the connection state between the display panel 1 and the circuit board 7 in the state 1 and the state 2.
(A) and FIG. 3 (b). Similarly, FIG. 6A shows a case where the positions where C1 to Cn of the display panel electrodes 3 are placed on the circuit board electrodes are determined based on the connection state of the scanning signal electrodes CB1 and CBn + 2. Based on the determination result, the electrode selection circuit 55 determines the electrodes S1 to Sm and C1 of the display panel 1.
From the starting point of .about.Cn, the data signal is the m electrode, and the scanning signal is the n electrode, which is selected from the electrodes SB1 to SBm + 2 and CB1 to CBn + 2, and sends a signal to the liquid crystal driving circuit 51 to output a liquid crystal driving voltage to the selected electrode. As a result, it is possible to correctly display even if the components are mounted not only in the X-axis direction and the Y-axis direction but also obliquely.

Next, the procedure for detecting the connection state by the state detection circuit 54 will be described with reference to the circuit diagram of FIG. CB in X axis direction
1 is connected to the display panel electrode C1, the transistor P2 in the liquid crystal drive circuit 73 and the transistor P1 in the state detection circuit 72 are turned on, and the electrode CB1 is turned on.
And CB2. No voltage is applied to the other electrodes. When the electrode CB1 is connected to the electrode C1 of the display panel 71, a current flows through the liquid crystal cell 74 and the state detection circuit 7
A voltage is generated at point c via the second buffer K1. Electrode C
When no electrode of the display panel is connected to B1, no voltage is generated at point c. The voltage waveform at this time is shown in FIG. 8 (a) for the electrode CB2, and FIG. 8 (b) for the case where the point c is connected to the electrode of the display panel.
(C). Thus, CBn + 2, SB1, SB
For m + 1, the connection status with the panel electrode can be detected by sequentially applying a voltage to each adjacent electrode.

The same detection is performed on the electrodes of the circuit board 7 corresponding to the vicinity of the center of the display panel in the X-axis direction and the Y-axis direction. When it is detected that the electrodes are not connected, all the connections are made. It is determined that there is not.

(Third Embodiment) FIG. 9 is a structural view showing a third embodiment of the display device of the present invention. On the circuit board 7, m data signal electrodes 91 for driving the display panel 1 are arranged at equal intervals. An electrode 92 to which a non-lighting signal is constantly input is provided at an end of the data signal electrode 91 at intervals.
Is arranged. In the display panel 1, liquid crystal cells in more than m columns (rows) of the data signal electrodes 91 are arranged in a matrix, and m or more corresponding panel data signal electrodes 93 are also arranged. Here, the data signal electrode 91 on the circuit board 7 and the electrode 92 to which the non-lighting signal is always input are electrically connected to the panel data signal electrode 93 on the display panel 1 via the elastic connector 6. . Further, in the case where the display panel 1 and the circuit board 7 are mounted with the positional relationship deviated at the time of mounting due to dimensional tolerances, re-assembly or mounting in a pitch-shifted state is possible as described in the first embodiment. .

FIG. 10 is a block diagram showing a circuit configuration of the display driver 12. The liquid crystal drive circuit 51 is connected from SB1 to SBm to which the panel data signal electrode 93 of the display panel 1 is connected, and from CB1 to CB to which the panel scanning signal electrode is connected.
Data lines up to Bn are prepared. At this time, the number of panel data signal electrodes 93 of the display panel 1 is m or more, which is larger than that of the data signal electrodes 91 of the circuit board 7. Further, a Soff data line connected to the electrode 92 to which a non-lighting signal is always input is prepared. The liquid crystal driving circuit 51 generates a liquid crystal driving voltage based on the timing generated by the display timing generating circuit 52 and the potential required for liquid crystal display by the power supply circuit 53, and displays the liquid crystal. In Soff, a non-lighting signal is always generated.

According to the above configuration, one end of the panel data signal electrode 93 of the display panel 1 is not connected to the data signal electrode 91 on the circuit board 7, and one end of the display panel 1 is connected to the data signal electrode 91 on the circuit board 7. Despite the presence of dots,
Although there is a portion that is not included in the display, this is not a problem in practical use. Further, the panel data signal electrodes 9 not included in this display are displayed.
3 is connected to the electrode 92 to which a non-lighting signal is always input, so that display unevenness such as crosstalk can be prevented. Also, as in the first embodiment, the permissible shift amount during mounting can be set to be equal to or larger than the pitch dimension, and connection at a narrower pitch than in the related art is possible.

Although the data signal has been described here,
Similarly, on the scanning signal side, electrodes 92 to which a non-lighting signal is always input are arranged at intervals at the ends of the scanning signal electrodes of the circuit board 7, and the number of panel scanning signal electrodes of the display panel 1 is set to be larger than that of the substrate side By doing so, similar embodiments and effects can be obtained.

Instead of providing an electrode 92 to which a non-lighting signal is always input on the scanning signal side, a liquid crystal cell corresponding to at least one column at one end or both ends of the scanning signal electrode of the circuit board 7 is always turned off. A similar effect can be obtained by creating an appropriate data signal.

[0032]

As described above, according to the present invention, by making the electrode pitch of the display panel and that of the circuit board the same, and by setting one of the number of electrodes to be a spare, the elastic connector is used. When the display panel and the circuit board are connected, the positional deviation can be allowed to be equal to or larger than the electrode pitch, and the elastic connector can easily be connected at a narrow pitch.

Further, when a spare electrode is provided on the display panel side, no special adjustment is required since only the spare portion is not provided for display.

Also, when a spare electrode is provided on the circuit board side, the electrode connection state is detected, and the electrode used for driving is selected from the circuit board, so that it can be easily mounted.

Further, a spare electrode is provided on the display panel side,
When liquid crystal cells not provided for display are provided, by connecting these to an electrode to which a non-lighting signal is input, display unevenness can be prevented.

As described above, it is possible to mount a narrow-pitch, high-definition panel and a circuit board easily and in a small size by using an elastic connector.

[Brief description of the drawings]

FIG. 1 is a sectional view of a module of a display device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of the module of the display device when FIG. 1 is viewed from another angle.

FIG. 3 is a cross-sectional view illustrating a connection state between a display panel and a circuit board. (A) is a display panel and circuit board electrodes SB1 to SB
The state diagram in which Bm was connected. (B) is a state diagram in which the display panel and the circuit board electrodes SB2 to SBm + 1 are connected.

FIG. 4 is a configuration diagram of a second embodiment of the display device of the present invention.

FIG. 5 is a circuit configuration diagram of a liquid crystal display driver of the display device of the present invention.

FIG. 6 is a diagram showing an electrode connection state of a detection state circuit and its determination. (A) relates to a data signal signal electrode, and (b) relates to a scanning signal electrode.

FIG. 7 is a circuit diagram showing a detection state.

8A is a potential waveform of CB1 in FIG. 7, FIG. 8B is a potential waveform of c in FIG. 7 when an electrode is connected, and FIG. 7C is a diagram of FIG. 7 when an electrode is not connected. 5 is a potential waveform of c.

FIG. 9 is a cross-sectional view illustrating a connection state between a display panel and a circuit board according to a third embodiment of the display device of the present invention.

FIG. 10 is a circuit configuration diagram of a liquid crystal display driver according to a third embodiment of the display device of the present invention.

[Explanation of symbols]

 P1 transistor P2 transistor K1 buffer

Claims (4)

[Claims] An elastic connector is arranged between a matrix type display panel and a circuit board having a display driver of the display panel, and an electrode of the display panel and an electrode for driving the display panel on the circuit board. In the display device for electrically connecting the electrodes, the arrangement pitch of the electrodes of the display panel and the electrodes for driving the display panel of the circuit board is the same, and the number of electrodes of the display panel and the display of the circuit board are different. A display device having a different number of electrodes for driving a panel. 2. The display panel driving electrode on the circuit board comprises a scanning signal electrode and a data signal electrode, and the display panel electrode comprises a panel scanning signal electrode and a panel data signal electrode. The number of the scanning signal electrodes is n, and the number of the data signal electrodes is m, i and j.
When at least one of them is a natural number of 1 or more, the display panel has liquid crystal cells arranged in a matrix of n + i rows and m + j columns, and has n + i panel scan signal electrodes and m + j panel data signal electrodes. The display device according to claim 1, wherein: 3. An electrode of the display panel comprises a panel scanning signal electrode and a panel data signal electrode, and the display panel driving electrode on the circuit board comprises a scanning signal electrode and a data signal electrode. When the number of electrodes is n, the number of panel data signal electrodes is m, and at least one of i and j is a natural number of 1 or more, the circuit board includes n + i scan signal electrodes and m + j data signal electrodes. A connection state in which the display driver detects a connection state between an electrode of the display panel and an electrode for driving the display panel of the circuit board after connecting the display panel and the circuit board with the elastic connector. The detection circuit and the electrodes used to drive the display panel are selected from the electrodes for driving the display panel on the circuit board. Display device according to claim 1, characterized in that it comprises an electrode selection circuit for the electrodes as many selection panels. 4. An elastic connector is disposed between a matrix type display panel and a circuit board having a display driver of the display panel, and an electrode of the display panel and the display panel driving circuit on the circuit board. In a display device for electrically connecting electrodes, the electrodes for driving the display panel on the circuit board are composed of scanning signal electrodes and data signal electrodes, and the electrodes of the display panel are panel scanning signal electrodes and panel data signal electrodes. At one or both ends of one or both of the scanning signal electrodes or the data signal electrodes on the circuit board in the electrode array direction,
One or more non-lighting signals of the display panel have electrodes to which a non-lighting signal is always input, and the display panel has the number n of the scanning signal electrodes on the circuit board, the number m of the data signal electrodes, and i
When at least one of j and j is a natural number of 1 or more, the liquid crystal cells are arranged in a matrix of n + i rows and m + j columns, and have n + i panel scan signal electrodes and m + j panel data signal electrodes. The display, wherein an electrode to which a non-lighting signal of the display panel is always input and the panel scanning signal electrode or the panel data signal electrode are electrically connected at one or more locations by the elastic connector. apparatus.