JP2004163827A - Transparent display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transparent display apparatus having a passive matrix type panel in which the proportion of the display region with respect to the whole panel size can be increased and decrease and irregularity in luminance can be suppressed. <P>SOLUTION: For example, an EL display apparatus is configured by providing an EL panel 10 with a connecting means such as a rubber connector 11 on three edges of the panel. Thereby, the both ends of first transparent electrodes arranged in horizontal stripes in the EL panel 10 are electrically connected to a scanning driver IC in a circuit board 13. Further, one end of second transparent electrodes arranged in vertical stripes in the EL panel 10 is electrically connected to a driving driver IC in the circuit board 13. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a transparent display device.
[0002]
[Prior art]
Conventionally, an EL (Electro Luminescence) display device is one of the transparent display devices. This is one in which the panel is configured as a transparent display section on which EL elements are formed. FIG. 10 shows a cross-sectional view of the panel.
[0003]
As shown in FIG. 10, a panel used in an EL display device (hereinafter, referred to as an EL panel) includes a first electrode 2, a first insulating film 3, a light emitting layer 4, and a second insulating film on a glass substrate 1. 5, a second electrode 6, an adhesive 7, and a cover glass 8 are laminated. In particular, it is known that an EL panel as a transparent display unit can be formed by forming the first electrode 2 and the second electrode 6 with a transparent electrode such as ITO (Indium Tin Oxide).
[0004]
As a structure of a display device using such an EL panel, for example, a structure in which a connection terminal portion is provided only at one edge of the EL panel has been proposed (see Patent Document 1). In this EL display device, a passive matrix type EL panel in which the first electrode 2 and the second electrode 6 have a stripe shape and are arranged so as to intersect vertically and horizontally is used.
[0005]
When the shape of the glass substrate 1 constituting the EL panel is substantially rectangular, connection terminals are not provided on the upper edge and the left and right side edges, and connection terminals are provided only on the lower edge of the EL panel. I have. In this connection terminal portion, a transparent electrode wiring made of ITO extends from both the electrodes 2 and 6, so that the electrode wiring and the circuit board are electrically connected. As a result, the EL panel is in a transparent state without a frame portion at the upper edge portion and the left and right side edge portions.
[0006]
[Patent Document 1]
Japanese Patent No. 2848236 (FIG. 5)
[0007]
[Problems to be solved by the invention]
However, in the transparent EL display device having the above-described structure, the first electrode 2 and the second electrode 6 are connected to the connection terminal portions by the transparent electrode wiring, and the transparent electrode wiring is arranged in the panel. It is necessary to secure an area. For this reason, there is a problem that the display area in the panel becomes smaller than the panel size.
[0008]
Furthermore, since the wiring of the ITO electrode is routed, the wiring length of the ITO electrode is correspondingly increased, and the wiring resistance is increased. Further, when only one end of the first electrode is electrically connected to the circuit board as in the above-described structure, the end of the first electrode in the region near the end and the end in the region far from the end are different. Since the distance from the electrode is different, the wiring resistance of the electrode itself is different. For these reasons, there is a problem that the luminance is reduced and the luminance is uneven.
[0009]
In view of the above, the present invention can provide a transparent display device in which the ratio of the display area to the entire panel size can be made larger than that of the above-described conventional structure, and which can suppress luminance reduction and luminance unevenness. It is an object to provide a display device.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the invention, connection means (11, 21, 22) are provided at three edges of the transparent display unit, and both ends of the first transparent electrode and the second transparent electrode are provided. Is characterized in that one end on one side is electrically connected to the circuit board via connection means at the closest one of the three edges.
[0011]
As described above, since both ends of the first transparent electrode and one end of one side of the second transparent electrode are connected to the connection means at the closest edge of the edge of the transparent display portion, the conventional structure described above is used. There is no need to secure a region for routing the electrode wiring. Thus, the display area can be made larger than in the above-described conventional structure.
[0012]
Further, since it is not necessary to route the electrode wiring, the length of the electrode wiring can be made shorter than that of the above-described conventional structure, and the wiring resistance of the first transparent electrode and the second transparent electrode can be reduced. As a result, it is possible to suppress a decrease in brightness and uneven brightness.
[0013]
Furthermore, since both ends of the first transparent electrode are electrically connected to the circuit board, a voltage can be applied to both ends of the first transparent electrode. For this reason, compared to the case where only one end of one side of the first transparent electrode is electrically connected to the circuit board as in the above-described conventional structure, the variation in wiring resistance at each portion of the first transparent electrode is reduced. And a reduction in luminance and luminance unevenness can be suppressed.
[0014]
As a connecting means, a rubber connector (11) in which a plurality of electrodes are fixed to rubber can be used. Further, the circuit board may have a U-shape along, for example, three edges of the transparent display section.
[0015]
Further, a flexible printed wiring board (21, 22) can be used as the connecting means. In this case, it is preferable that the shape of the flexible printed wiring board (21, 22) is a shape as described in claim 5.
[0016]
Specifically, of the three edges of the transparent display unit, the first and second edges connected to both ends of the first transparent electrode are parallel to the edges of the first and second edges. The third edge of the transparent display portion, which can be bent around the axis and is connected to one end of one side of the second transparent electrode, among the three edges of the transparent display portion, is located between the third edge and the circuit board. The shape is such that it can be bent around an axis parallel to the side of the third edge.
[0017]
According to the invention of claim 5, the flexible printed wiring board can be rounded and reduced at the first and second edges of the transparent display portion, and the width of the frame provided at the first and second edges Can be narrowed. Thus, by providing the frames at both edges of the transparent display unit, it is possible to suppress the loss of transparency as compared to a case where no frame is provided.
[0018]
Further, since the portion connecting the third edge of the transparent display portion and the circuit board can be bent about an axis parallel to the side of the lower edge portion, the transparent display portion and the circuit board are overlapped. A transparent display device having a structure that can be folded as described above can be provided.
[0019]
In addition, the code | symbol in the parenthesis of each said means shows the correspondence with the concrete means described in embodiment mentioned later.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
(1st Embodiment)
FIG. 1 shows the appearance of the EL display device according to the first embodiment of the present invention, and FIG. 2 shows a diagram of the EL display device shown in FIG. 1 when disassembled. FIG. 3 schematically shows the electrode wiring of the EL panel.
[0021]
As shown in FIG. 2, the EL display device according to the present embodiment includes a cover 9, an EL panel 10, a rubber connector 11, a spacer 12, a circuit board 13, and a cover 14 in this order from the near side to the far side in the drawing. Are arranged. The EL panel 10 is sandwiched by the covers 9 and 14 and the like, and the cover 9, the spacer 12, the circuit board 13, and the cover 14 are fixed by the screw 15.
[0022]
As shown in FIG. 10, the EL panel 10 includes a first electrode 2, a first insulating film 3, a light emitting layer (EL light emitting layer) 4, a second insulating film 5, and a second electrode 6 on a glass substrate 1. Is formed by vacuum evaporation or sputtering, and a cover glass 8 is adhered to the glass substrate 1 via an adhesive 7 for protection against pressure.
[0023]
The first electrode 2 and the second electrode 6 in the EL panel 10 are made of ITO and are transparent. Then, as shown in FIG. 3, the first electrode 2 has a horizontal stripe shape, and the second electrode 6 has a vertical stripe shape, and the first electrode 2 and the second electrode 6 are orthogonal to each other. .
[0024]
A portion where the first electrode 2 and the second electrode 6 are orthogonal to each other forms a pixel together with the first insulating film 3, the second insulating film 5, and the light emitting layer 4 sandwiched between the electrodes 2, 6. By applying a voltage between the first electrode 2 and the second electrode 6, this pixel can emit light. A region where the pixels are arranged in a lattice shape is a display region 10a in the EL panel 10.
[0025]
Further, there is an edge 10b of the EL panel 10 as a space for electrically connecting the first electrode 2 and the second electrode 6 to the circuit board 13. Both ends of the first electrode 2 extend to both left and right edges 10b of the EL panel 10, and one end of one side of the second electrode 6 extends to the lower edge 10b of the EL panel 10.
[0026]
Note that the first electrode 2 and the second electrode 6 correspond to a first transparent electrode and a second transparent electrode described in claims, respectively. Further, the EL panel 10 corresponds to a transparent display unit described in the claims.
[0027]
Here, the light emitting layer 4 is made of, for example, a semiconductor material such as ZnS or ZnSe, and Mn, Tb, Sm, or the like can be used as a light emitting center. The emission center emits yellow-orange light when Mn is used, emits green light when Tb is used, and emits red light when Sm is used. The first insulating film 3 and the second insulating film 5 are made of a dielectric material such as TiO ₂ , Al ₂ O ₃ , SiO ₂ , Si ₃ N _{4 and the} like.
[0028]
As shown in FIG. 2, the rubber connector 11 is disposed between the EL panel 10 and the circuit board 13, and is inserted into a square hole-shaped holder 12 a formed on the spacer 12. The rubber connector 11 is held between the EL panel 10 and the circuit board 13 together with the spacer 12.
[0029]
As a result, the rubber connector 11 is compressed between the EL panel 10 and the circuit board 13, and the electrodes respectively corresponding to the EL panel 10 and the circuit board 13 are electrically connected via the rubber connector 11. Note that the rubber connector 11 corresponds to a connecting means described in the claims.
[0030]
Here, an external perspective view of the rubber connector 11 is shown in FIG. Specifically, as shown in FIG. 4, the rubber connector 11 has a configuration in which, for example, a plurality of metal electrodes 17 are attached to a silicon rubber 16 having a prismatic shape. The metal electrode 17 is made of, for example, brass and has a wire diameter of about 30 μm. The pitch 17a of the metal electrodes 17 is 50 μm.
[0031]
5 and 6 show how the rubber connector 11 connects the EL panel 10 and the circuit board 13. FIG. FIG. 5 is a sectional view taken along line AA of FIG. 1, and FIG. 6 is a view taken along arrow B of FIG.
[0032]
As shown in FIG. 5, when the rubber connector 11 is compressed between the EL panel 10 and the circuit board 13, the first electrode 2 of the EL panel 10 and the electrode 20 of the circuit board 13 become metal electrodes. 17 are electrically connected. At this time, good connection can be achieved by setting the compression ratio of the rubber connector 11 to 10 to 40%. The second electrode 6 of the EL panel 10 is also electrically connected to the electrode of the circuit board 13 in the same manner.
[0033]
As shown in FIG. 6, when the pitch 17a of the metal electrodes 17 in the rubber connector 11 is very narrow, the pitch 2a of the first electrodes 2 of the EL panel 10 and the pitch 20a of the electrodes 20 of the circuit board 13 are used. Is made larger than the pitch 17a of the metal electrodes 17. Thereby, the corresponding first electrode 2 of the EL panel 10 and the electrode 20 of the circuit board 13 can be electrically connected.
[0034]
As described above, in the present embodiment, the EL panel 10 is held between the EL panel 10 and the circuit board 13 by sandwiching the rubber connector 11 between the EL panel 10 and the circuit board 13. Are electrically connected. Since the EL panel 10 and the rubber connector 11 are not directly fixed, the attachment and detachment of the EL panel 10 and the rubber connector 11 are easy. For this reason, in the EL display device of the present embodiment, when a failure occurs in the EL panel 10, only the EL panel 10 can be replaced, and the repairability is excellent.
[0035]
As shown in FIG. 2, the circuit board 13 has a U-shape, and has a size that overlaps the left and right edges 10 b and the lower edge 10 b of the EL panel 10. In addition, the U-shape in this specification includes a U-shape with rounded corners and a shape having corners such as a U-shape, as the wording implies. Although not shown in FIG. 2, the circuit board 13 includes a drive driver IC 18 and a scan driver IC 19 (see FIG. 3).
[0036]
As shown in FIG. 3, the drive driver IC 18 is electrically connected to the vertical stripe-shaped second electrode 6, and the scan driver IC 19 is electrically connected to the horizontal stripe-shaped first electrode 2. I have. In particular, although not shown, the scan driver IC 19 is branched in the pattern of the circuit board 13 and connected to both ends of the first electrode 2, and is capable of transmitting a scan signal to the first electrode 2 from both left and right sides. It is possible.
[0037]
The EL display device configured as described above transmits a drive signal from the drive driver IC 18 to the second electrode 6 as a drive electrode by applying a voltage of, for example, 40 to 60 V to the drive driver IC 18. Further, by applying a voltage of, for example, 200 to 250 V to the scan driver IC 19, a scan signal is transmitted from the scan driver IC 19 to the first electrode 2 as a scan electrode.
[0038]
As a result, by selecting and emitting light from the light-emitting pixels at the intersections of the first electrode 2 and the second electrode 6, characters, figures, and the like are displayed on the EL panel 10.
[0039]
As described above, in the EL display device of the present embodiment, in the EL panel 10 in which the pixels that are the intersections of the first electrode 2 and the second electrode 6 are arranged in a matrix, the first electrode 2 as the scanning electrode is The left and right edges 10b of the EL panel 10 are electrically connected to the scan driver IC 19 of the circuit board 13 via the rubber connector 11. The second electrode 6 as a drive electrode is electrically connected to the drive driver IC 18 of the circuit board 13 via the rubber connector 11 at the lower edge 10b of the EL panel 10.
[0040]
As described above, in the present embodiment, both ends of the first electrode 2 and one end on one side of the second electrode 6 are connected to the rubber connector 11 at the closest edge 10b among the three edges 10b of the EL panel 10. .
[0041]
Thus, unlike the EL display device having the structure described in the section of the related art, it is not necessary to secure an area for arranging the electrode wiring on the side edge portion 10 of the EL panel 10. Thereby, the display area 10a can be enlarged as compared with the conventional structure described above. Furthermore, since the electrode wiring between the display area 10a and the rubber connector 11 can be shortened and the wiring resistance can be reduced, it is possible to suppress a reduction in brightness and uneven brightness.
[0042]
When only one end of the left and right ends of the first electrode 2 is connected to the circuit board 13 as in the above-described conventional structure, a portion of the first electrode 2 close to the rubber connector 11 is connected to the rubber connector 11. Since the wiring length from the rubber connector 11 is different between a part far from the wiring connector and the wiring resistance, the wiring resistance is greatly different. For this reason, luminance reduction and luminance unevenness occur.
[0043]
On the other hand, in the present embodiment, a scanning driver IC 19 is connected to both ends of the first electrode 2 via the rubber connector 11, and a scanning signal is transmitted to both ends of the first electrode 2. For this reason, the difference in wiring resistance from the rubber connector 11 to each part of the first electrode 2 can be reduced, and a reduction in luminance and luminance unevenness can be suppressed. Thus, an EL display device in which a decrease in display quality is suppressed can be obtained.
[0044]
In the present embodiment, both ends of the first electrode 2 as the scanning electrode are connected to the rubber connector 11 because, as described above, a higher voltage is applied to the scanning electrode than to the driving electrode. This is because the wiring resistance of the scanning electrode has a greater effect on luminance than the wiring resistance of the driving electrode.
[0045]
Further, according to the present embodiment, since the scanning signal is transmitted to both ends of the first electrode 2, the distance to the part farthest from the rubber connector 11 is adjusted within a range shorter than the above-described conventional structure. Also, as compared with the above-described conventional structure, it is possible to increase the size of the EL panel 10 while suppressing the luminance reduction and the luminance unevenness.
[0046]
Further, in the present embodiment, the circuit board 13 and the covers 9 and 14 form a frame of the EL panel 10, and the frame is provided at the three edges 10b. Compared to a structure in which connection terminals are provided only at one edge of the EL panel 10, the EL display device of the present embodiment loses transparency due to the left and right frame portions. Rather than having a structure in which a frame portion is provided at the four edges of 10, a sense of transparency is ensured.
[0047]
The width of the left and right frame portions of the EL panel 10 can be further reduced by forming the circuit board 13 in a multilayer structure. Thereby, the transparency of the EL panel 10 can be enhanced.
[0048]
In the present embodiment, the shape of the circuit board 13 is U-shaped. However, the circuit board 13 is overlapped with the left and right edges 10b and the lower edge 10b of the EL panel 10 so that the transparency of the EL panel 10 is not impaired. If so, other shapes can be used.
[0049]
For example, the portion of the circuit board 13 in the present embodiment on the lower edge portion 10b side of the EL panel 10 has no particular influence on the transparency of the EL panel 10. Accordingly, the EL panel 10 can be formed in a shape in which a convex portion, a concave portion, and the like are further provided on the lower edge portion 10b side.
[0050]
(2nd Embodiment)
7, 8, and 9 show an EL display device according to the second embodiment. The difference between the EL display device of the present embodiment and the structure of the first embodiment shown in FIG. 1 is that, as shown in FIG. 7, an FPC (Flexible Printed Wiring Board) is mainly used instead of the rubber connector 11 as connection means. 21 and 22 are used. A further preferred form is shown in FIG.
[0051]
As shown in FIG. 8, the FPC 21 is connected to both left and right edges 10b of the EL panel 10. The portion of the FPC 21 connected to the left and right edges 10b of the EL panel 10 can be rounded (in the direction of the arrow A in the figure) about an axis parallel to the side of the side edge 10b of the EL panel 10. The lower part of the EL panel 10 has a crank shape so that it can be bent around an axis parallel to a side of the lower edge 10b of the EL panel 10 (in the direction of arrow B in the figure).
[0052]
In other words, the FPC 21 is rounded at a portion connected to the left and right edges 10b of the EL panel 10 so as to reduce the width of the frame provided on the left and right edges 10b of the EL panel 10, and The lower side of the panel 10 has a crank shape so that the EL panel 10 and the circuit board 13 can be bent so as to face each other at a position between the EL panel 10 and the circuit board 13.
[0053]
The left and right edges 10b correspond to first and second edges described in the claims, and the lower edges 10b correspond to third edges described in the claims.
[0054]
The circuit board 13 has a rectangular shape and includes a driving driver IC 18 and a scanning driver IC 19. The FPC 21 electrically connects the first electrode in the EL panel 10 to the scan driver IC 19 in the circuit board 13.
[0055]
The FPC 22 has a rectangular shape whose longitudinal direction is shorter than the circuit board 13, and is connected to the lower edge 10 b of the EL panel 10. The FPC 22 electrically connects the second electrode in the EL panel 10 to the drive driver IC 18 in the circuit board 13.
[0056]
8, the FPC 21 connected to the left and right side edges 10b of the EL panel 10 is rolled up and placed in a case or the like, thereby reducing the width of the frame provided on the left and right side edges 10b of the EL panel 10. be able to. Thereby, the transparency of the EL panel 10 can be prevented from being impaired as compared with the above-described conventional structure.
[0057]
Further, at a position between the EL panel 10 and the circuit board 13, the EL panel 10 and the circuit board 13 can be bent so as to face each other. From the above, according to the present embodiment, as shown in FIG. 9, a desktop display device having a folding structure can be obtained. FIG. 9 shows a state where the case 23 is attached to the EL panel 10 and the circuit board 13 is housed in the case 24.
[0058]
In the present embodiment, the shapes of the FPCs 21 and 22 are a crank shape and a rectangular shape, respectively. However, on the left and right edge portions 10b side of the EL panel 10, frames provided on the left and right edge portions 10b of the EL panel 10 are provided. The EL panel 10 and the circuit board 13 face each other at a position between the EL panel 10 and the circuit board 13 on the lower edge 10b side of the EL panel 10 so that the width of the section is reduced. Any other shape can be used as long as the shape can be bent.
[0059]
For example, the FPC 21 and the FPC 22 may be connected to each other on the lower side of the EL panel 10 in FIG. 8, and the FPC 21 and the FPC 22 may be integrated.
[0060]
(Other embodiments)
In each of the above-described embodiments, as shown in the drawings, the case where the shape of the EL panel 10 is rectangular has been described, but the shape of the EL panel 10 is not limited to a rectangle. In the EL panel 10, both ends of the first electrodes 2 arranged in a horizontal stripe are connected to connection means such as a rubber connector 11 or an FPC 21 at an edge 10b of the EL panel 10 closest to each end. Any other shape can be used as long as one end of the second electrode 6 arranged in a vertical stripe can be connected to the connection means at the edge 10b of the EL panel 10 closest to the other.
[0061]
For example, the shape of the EL panel 10 may be a shape obtained by rounding a rectangular corner, or a shape such as a trapezoidal shape. The shape of the transparent display portion described in the claims being substantially rectangular means that the shape is not limited to a rectangular shape but includes such a shape.
[0062]
Further, in each of the above-described embodiments, the first transparent electrode 2 and the second transparent electrode 6 are made of the ITO transparent material including the connection portion with the circuit board 13. May be made of a low-resistance metal material. In short, it is only necessary that a portion where these electrodes intersect to form a pixel is made of a transparent electrode material.
[0063]
In each of the embodiments described above, the EL display device has been described. However, the present invention is of course applicable to a transmissive liquid crystal display device and a transmissive fluorescent display device.
[Brief description of the drawings]
FIG. 1 is a front view illustrating an appearance of an EL display device according to a first embodiment of the present invention.
FIG. 2 is a diagram showing a state when the EL display device of FIG. 1 is disassembled.
3 is a diagram schematically showing an arrangement of electrode wirings in an EL panel of the EL display device of FIG. 1 and a connection state with each driver IC.
FIG. 4 is a perspective view showing an appearance of a rubber connector used in the EL display device of FIG. 1;
5 is a diagram showing a connection state between an EL panel and a circuit board when a rubber connector is used in the EL display device of FIG. 1, and is a cross-sectional view taken along line AA in FIG. 1;
FIG. 6 is a diagram showing a connection state between the EL panel and the circuit board when a rubber connector is used in the EL display device of FIG. 1, and is a view taken in the direction of arrow B in FIG. 1;
FIG. 7 is a front view illustrating an appearance of an EL display device according to a second embodiment of the present invention.
FIG. 8 is a front view illustrating an appearance of an EL display device according to a second embodiment of the present invention.
FIG. 9 is a perspective view illustrating an appearance of an EL display device according to a second embodiment of the present invention.
FIG. 10 is a cross-sectional view showing a structure of an EL panel according to the present invention and a conventional structure.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Glass substrate, 2 ... 1st electrode, 3 ... 1st insulating film, 4 ... Light emitting layer,
5 ... second insulating film, 6 ... second electrode, 7 ... adhesive, 8 ... cover glass,
9, 14 ... cover, 10 ... EL panel, 11 ... rubber connector,
12 ... spacer, 13 ... circuit board, 15 ... screw,
16 silicon rubber, 17 metal electrodes, 18 driver IC,
19: scan driver IC, 20: electrode wiring of circuit board,
21, 22: FPC, 23, 24: Case.

Claims (5)

A first transparent electrode (2) and a second transparent electrode (6), both of which form a stripe shape, are arranged so as to intersect with each other, and at the intersection of the first transparent electrode (2) and the second transparent electrode (6). A transparent display device comprising: a substantially rectangular transparent display portion (10) provided with pixels; and a circuit board (13) electrically connected to the first transparent electrode and the second transparent electrode. ,
Connection means (11, 21, 22) for electrically connecting the first transparent electrode, the second transparent electrode, and the circuit board are provided at three edges of the transparent display unit, Both ends of one transparent electrode and one end of one side of the second transparent electrode are electrically connected to the circuit board via the connection means at the closest one of the three edges. Characteristic transparent display device. A rubber connector (11) in which a plurality of electrodes (17) are fixed to a rubber (16) is used as the connection means,
The rubber connector is disposed between the circuit board and the transparent display section, and the rubber connector is sandwiched between the circuit board and the transparent display section, so that the circuit board, the first transparent electrode, and the second transparent The transparent display device according to claim 1, wherein the transparent display device is electrically connected to an electrode. 3. The transparent display device according to claim 2, wherein the circuit board is U-shaped along the three edges of the transparent display unit. 4. The transparent display device according to claim 1, wherein a flexible printed wiring board (21, 22) is used as the connection unit. The flexible printed wiring board has a first and a second edge on a first and second edge side of the three edge portions of the transparent display portion connected to both ends of the first transparent electrode. The third edge portion of the transparent display portion, which is connected to one end of one side of the second transparent electrode, can be bent around an axis parallel to the side of the portion. 5. The transparent display device according to claim 4, wherein the transparent display device has a shape that can be bent about an axis parallel to a side of the third edge between the edge of the third edge and the circuit board. 6. .

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