JP2006228443A - Display panel, display module for moving body using same, and electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display panel capable of suppressing temperature unevenness in a panel for prolonging a service life, and to provide a display module for a moving body using this and an electronic device. <P>SOLUTION: An organic EL panel 20 includes a light emitting element substrate 21 wherein a plurality of pixels 220 having organic EL device 221 respectively are arranged and a sealing substrate 22 connected with the light emitting element substrate 21 to seal the plurality of pixels. In the organic EL panel 20, a desiccating agent 23 capable of absorbing water is arranged over the whole display area 21a of the light emitting element substrate 21 in a space between the light emitting element substrate 21 and the sealing substrate 22 as a plate-like temperature distribution uniforming means uniforming temperature distribution. The desiccating agent 23 is formed in a plate larger than the display area 21a, and can uniform the temperature distribution of the panel over the whole display area while absorbing the water infiltrating into the space 25. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a display panel such as an organic EL panel, a mobile display module using the display panel, and an electronic apparatus.

In recent years, organic EL (electroluminescence) panels using organic EL elements have attracted attention as being superior to other devices in terms of low power consumption ratio, high viewing angle, and high contrast ratio.
As such an organic EL panel, a substrate in which a plurality of pixel electrodes, organic EL elements, thin film transistors, and a plurality of wirings are formed, and a sealing in which an annular projection is bonded to the peripheral edge of the substrate so as to cover the entire plurality of pixels There is known an organic EL element including a member and having an absorbent that can absorb moisture or the like adhered to the inner surface of the sealing member (see, for example, FIG. 3 of Patent Document 1).

In this organic EL device, a rectangular pixel electrode made of a transparent conductive material and functioning as an anode is formed in a matrix on a substrate, and a hole injection / transport layer and a light emitting layer are formed on each pixel electrode. And the cathode is formed over almost the entire surface of the substrate on which the light emitting layer is formed. In addition, a thin film transistor (TFT) or the like is electrically connected to each pixel electrode, and each pixel electrode, a hole injection / transport layer formed thereon, a light emitting layer, and a cathode constitute one organic EL element. Is configured.
JP 2003-208976 A

  By the way, in the conventional organic electroluminescent panel (organic electroluminescent apparatus) as described in the said patent document 1, as a desiccant stuck to the inner surface of a sealing member, the structure which spreads four rectangular desiccants. As a result of measuring the temperature of the panel while continuously energizing and conducting a life test, it was found that the thermal conductivity was high only where there was a desiccant. Since the thermal conductivity is high only where there is a desiccant, the part with the desiccant on the panel cools, and the part without the desiccant on the panel (the part of the cross-shaped gap between the four desiccants) becomes hot. . Thus, it was found that temperature unevenness in the panel, that is, a temperature distribution having a high temperature portion and a low temperature portion was formed. If there is uneven temperature in the panel, the relationship between the panel temperature and the luminance half-life of the organic EL panel is the same in the same panel, the portion with a short luminance half-life (high temperature portion) and the portion with the same lifetime (low temperature) There is a problem that the panel life is shortened.

  The present invention has been made paying attention to such conventional problems, and the purpose thereof is to use a display panel that can suppress the occurrence of temperature unevenness in the panel and can prolong the life. It is an object of the present invention to provide a mobile display module and an electronic device.

  The display panel according to the present invention includes a light emitting element substrate in which a plurality of pixels each having a light emitting element are arranged in a matrix, and a sealing substrate bonded to the light emitting element substrate so as to seal the plurality of pixels. The gist of the display panel is that plate-like temperature distribution uniforming means for uniforming temperature distribution is arranged in the entire display area in the space between the light emitting element substrate and the sealing substrate.

According to this, since the temperature distribution of the panel can be made uniform over the entire display area by the temperature distribution uniforming means, it is possible to suppress the occurrence of temperature unevenness in the entire display area of the panel, and to extend the life of the panel. Can do. Such an effect is particularly effective when the size of the display panel is large.

  The gist of the display panel is that the temperature distribution uniforming means is a desiccant spread over a range larger than the display area and fixed to the inner surface of the sealing substrate. According to this, the desiccant exhibits the original function of absorbing moisture that has entered the space between the light emitting element substrate and the sealing substrate, and the desiccant equalizes the temperature distribution of the panel over the entire display area. can do.

  In this display panel, the desiccant is a desiccant formed in a plate shape larger than the display area. According to this, the original function that one desiccant larger than the display area absorbs moisture that has entered the space is exhibited, and the temperature distribution of the display panel can be made uniform over the entire display area.

  In this display panel, the desiccant is composed of a plurality of desiccants formed in a plate shape, and the summary is that the plural desiccants are spread over a range larger than the display area. According to this, a plurality of desiccants spread over a range larger than the display area can perform the original function of absorbing moisture that has entered the space, and the temperature distribution of the display panel can be made uniform over the entire display area. Can do.

  In this display panel, the temperature distribution uniform means includes a desiccant formed in a plate shape fixed to the inner surface of the sealing substrate, and one thin metal plate fixed to the desiccant and larger than the display area. It is made up of the following. According to this, the desiccant exhibits the original function of absorbing moisture that has entered the space, and the temperature distribution of the display panel over the entire display area is achieved by one thin metal plate fixed to the desiccant. Can be made uniform. Therefore, it is possible to further suppress the occurrence of temperature unevenness in the display panel, and to further increase the life of the display panel.

  The gist of the display panel is that the metal plate is disposed so as to have a gap between the metal plate and the light emitting element substrate. According to this, since heat generated on the light emitting element substrate side is indirectly transmitted to one thin metal plate through the space, it is possible to further suppress the occurrence of temperature unevenness in the display panel, and to improve the lifetime of the display panel. Can be made even longer.

  This display panel is characterized in that a large number of through holes are provided in the entire metal plate. According to this, since the area where the desiccant comes into contact with the air in the space through a large number of through holes provided in the thin metal plate is increased, the moisture that has entered the space is effectively absorbed by the desiccant. Will come to be.

  The gist of the display panel is that the light-emitting element is an electroluminescence element. According to this, the lifetime of electroluminescent panels, such as an organic electroluminescent panel using an electroluminescent element, can be lengthened.

  The gist of the display module of the moving body according to the present invention is that a plurality of the display panels displaying different images are mounted side by side on the panel support member. According to this, the lifetime of a plurality of display panels can be extended, and high-quality display can be maintained for a long time. Therefore, when mounted on vehicles such as automobiles, aircraft, ships, trains, etc. where durability and safety are important, the speed of the moving body, the engine speed, the map information of the navigation device, etc. are displayed in multiple numbers. The panel can display with high quality for a long time.

The gist of the electronic apparatus according to the present invention is that the display panel is used. According to this, the lifetime of the display panel can be extended and high-quality display can be maintained over a long period of time.

Hereinafter, embodiments embodying the present invention will be described with reference to the drawings. In the description of each embodiment, similar parts are denoted by the same reference numerals, and redundant description is omitted.
(First embodiment)
The structure of the organic EL panel according to the first embodiment will be described with reference to FIGS.

  The organic EL panel 20 as a display panel is an organic EL panel as an electroluminescence panel using an electroluminescence (EL) element as a light emitting element. As shown in FIGS. 1 and 2, the organic EL panel 20 includes a light emitting element substrate 21 in which a plurality of pixels 220 each having an organic EL element 221 as an electroluminescence element are arranged in a matrix, and a plurality of pixels. And a sealing substrate 22 bonded to the light emitting element substrate 21 so as to be sealed. In FIG. 1, only one of the plurality of pixels 220 is shown, and in FIG. 2, illustration of the plurality of pixels 220 and the organic EL element 221 of each pixel 220 is omitted.

  Further, the organic EL panel 20 has a plate-like temperature distribution uniforming means for making the temperature distribution uniform over the entire display area 21 a of the light emitting element substrate 21 in the space 25 between the light emitting element substrate 21 and the sealing substrate 22. A desiccant 23 capable of absorbing moisture is disposed. The “display area 21a” is a rectangular active area in which a plurality of pixels 220 are formed.

  Although not shown in FIG. 2, rectangular pixel electrodes functioning as anodes are formed in a matrix on the light emitting element substrate 21. For example, hole injection / transport is performed on each pixel electrode. A layer and a light emitting layer are sequentially laminated, and a cathode is formed over almost the entire surface of the substrate on which the light emitting layer is formed. In addition, a thin film transistor (TFT) or the like is electrically connected to each pixel electrode, and each pixel 220 includes a pixel electrode, a hole injection / transport layer formed thereon, a light emitting layer, and a cathode. An organic EL element 221 is configured. Further, as shown in FIG. 1, a terminal portion 200 of a plurality of wirings (not shown) including a plurality of power supply lines, a plurality of signal lines, and a plurality of control lines is formed on the light emitting element substrate 21. .

  The sealing substrate 22 is formed in a bottomed cylindrical shape having a rectangular convex portion 22a, and is made of, for example, a transparent glass substrate. In the sealing substrate 22, the lower end surface of the convex portion 22 a is bonded to the one surface 21 b of the light emitting element substrate 21 with an adhesive 24 so as to seal the entire plurality of pixels 220 (see FIG. 2). The one surface 21b is a surface opposite to the other surface (light emitting surface) 21c from which the light emitted from the organic EL element 221 of each pixel 220 is emitted.

  The desiccant 23 used in this example is formed in a single plate shape larger than the display area 21a. The length of one side (longitudinal side) of the desiccant 23 is Ag, the length of the other side (lateral side) is Bg, the length of one side of the light emitting element substrate 21 is A, and the length of the other side is Assuming B, a desiccant 23 having a size satisfying the relationship of Ag> A, Bg> B is joined to the inner surface of the sealing substrate 22 at a position that covers the entire display area 21a in plan view (FIG. 2). reference).

According to 1st Embodiment comprised as mentioned above, there exist the following effects.
The organic EL panel 20 has a plate-like temperature distribution uniforming means for making the temperature distribution uniform over the entire display area 21 a of the light emitting element substrate 21 in the space 25 between the light emitting element substrate 21 and the sealing substrate 22. A desiccant 23 is disposed. With this configuration, the desiccant 23 can perform its original function of absorbing moisture that has entered the space 25, and the temperature distribution of the panel can be made uniform over the entire display area. Therefore, it is possible to suppress the occurrence of temperature unevenness in the entire display area 21a of the organic EL panel 20, and the life of the organic EL panel 20 can be extended.

O Even if the size of the organic EL panel 20 is large, the glass of the light emitting element substrate 21 is not broken, and the life can be extended. Thus, when the size of the organic EL panel 20 is large, the effect that the lifetime can be extended is effectively exhibited.
(Second Embodiment)
The structure of the organic EL panel 20 according to the second embodiment will be described with reference to FIGS.

  In the organic EL panel 20 according to this embodiment, instead of the single desiccant 23 used in the first embodiment, a plurality of sheets (4 in this example) are used as plate-like temperature distribution uniforming means for uniforming the temperature distribution. Sheet) desiccants 26, 27, 28 and 29 are used. These four desiccants 26 to 29 each have a size obtained by dividing one desiccant 23 into four parts. The four desiccants 26 to 29 are spread over a range larger than the display area 21a while keeping the gaps within about 0.1 mm to 0.5 mm. Other configurations are the same as those in the first embodiment.

According to 2nd Embodiment comprised as mentioned above, in addition to the effect which the said 1st Embodiment show | plays, there exist the following effects.
○ Since four desiccants 26 to 29 are spread over a range larger than the display area 21a, standard desiccants can be commonly used as the desiccants 26 to 29 for organic EL panels of different sizes. .
(Third embodiment)
The structure of the organic EL panel 20 according to the third embodiment will be described with reference to FIGS.

  In the organic EL panel 20 according to the present embodiment, instead of the single desiccant 23 used in the first embodiment, the inner surface of the sealing substrate 22 is used as a plate-like temperature distribution uniforming means for uniforming the temperature distribution. A thin desiccant 23A formed in a plate shape fixed to a thin plate, and a thin stainless steel (SUS) 30 is used as one thin metal plate fixed to the desiccant 23A and larger than the display area 21a. In this example, the desiccant 23A is smaller than the desiccant 23 used in the first embodiment.

  Further, the stainless steel 30 is disposed so as to have a gap between the light emitting element substrate 21. Specifically, it arrange | positions so that a slight clearance gap may be made between the said cathodes. Thus, the stainless steel 30 is free with respect to the light emitting element substrate 21. Other configurations are the same as those in the first embodiment.

According to 3rd Embodiment comprised as mentioned above, in addition to the effect which the said 1st Embodiment show | plays, there exist the following effects.
○ Because the thin stainless steel 30 fixed to the desiccant 23A can make the temperature distribution of the organic EL panel 20 uniform over the entire display area 21a, temperature unevenness is less likely to occur in the entire display area 21a of the organic EL panel 20. . Therefore, it is possible to further suppress the occurrence of temperature unevenness in the organic EL panel 20 and to further extend the life of the organic EL panel 20.
(Fourth embodiment)
The structure of the organic EL panel 20 according to the fourth embodiment will be described with reference to FIG.

  This organic EL panel 20 uses a stainless steel 31 having a large number of through holes 31a formed in its entirety, instead of the stainless steel 30 in the third embodiment. Other configurations are the same as those of the third embodiment.

According to 4th Embodiment comprised as mentioned above, in addition to the effect which the said 3rd Embodiment show | plays, there exist the following effects.
O Since the area where the desiccant 23A comes into contact with the air in the space 25 through the numerous through holes 31a of the stainless steel 31 is increased, the moisture that has entered the space 25 is effectively absorbed by the desiccant 23A.

(Mobile display module)
Next, the mobile display module 1 using a plurality (three in this example) of the organic EL panels 20 described in the above embodiments will be described with reference to FIGS.

  As shown in FIG. 8, the moving body display module 1 includes three organic EL panels 2, 3, and 4, and one base plate 5. The three organic EL panels 2, 3, and 4 that display different images are equivalent to the organic EL panel 20, and are attached to one horizontally long base plate 5 in the longitudinal direction. Here, three panel assemblies D, E, and F each having three organic EL panels 2, 3, and 4 are attached to one base plate 5 side by side.

  The moving body display module 1 is mounted on an instrument panel 41 of a vehicle 40 as shown in FIG. FIG. 10 shows a state where the resin panel cover 80 is attached to the surface of the display module 1 of the moving body attached to the instrument panel 41 in this way. The panel cover 80 includes a speedometer circular opening 81 displayed in the display area 14 of the middle organic EL panel 2 and a tachometer circular opening displayed in the display area 14 of the right organic EL panel 3. A portion 82 and a rectangular opening 83 for an image displayed on the left organic EL panel 4 are provided. Each display area 14 of these organic EL panels 2 to 4 corresponds to the display area 21 a of the organic EL panel 20.

  Further, as shown in FIG. 10, for example, the display module 1 of the moving body displays a speedometer scale 91 for displaying the vehicle speed in an analog manner, a numeral 92, and a pointer 93 by the organic EL panel 2 in the middle. Further, a tachometer scale 94, numeral 95 and pointer 96 for analog display of the engine speed are displayed on the right organic EL panel 3, and an image 97 such as map information of the car navigation device is displayed on the left organic EL panel 4. . In addition, the organic EL panel 4 can also display an image of a television or an image of a DVD device.

  According to the mobile display module 1 having such a configuration, the lifetime of each of the organic EL panels 2 to 4 can be extended, and high-quality display can be maintained over a long period of time. Therefore, when mounted on a vehicle such as an automobile where durability and safety are important, the vehicle speed, the engine rotation, the map information of the car navigation device, etc. are provided with high quality over a long period of time by the three organic EL panels 2-4. Can be displayed.

(Electronics)
Next, an electronic apparatus using the organic EL panel 20 described in the above embodiments will be described. The organic EL panel 20 can be applied to a mobile personal computer as shown in FIG. A personal computer 70 shown in FIG. 11 includes a main body 72 having a keyboard 71 and a display unit 73 using the organic EL panel 20.

  According to the personal computer 70, the life of the display unit 73 can be extended and high-quality display can be maintained over a long period of time. In particular, even if the size of the display unit 73 is large, unevenness in luminance due to temperature distribution due to heat generation does not occur and the life can be extended.

In addition, this invention can also be changed and embodied as follows.
In each of the above embodiments, an organic EL panel used for an organic EL display is described as an example of the display panel. However, a display panel used for a fluorescent plasma display using discharge, a display (FED) using an electron-emitting device, The present invention can also be applied to a display panel used in an SED (Surface-Conduction Electron-Emitter Display), and the same effects as those in the above embodiments can be obtained.

  In the first embodiment, one desiccant 23 formed in a plate shape is used, and in the second embodiment, four desiccants 23A are used. However, the present invention is not limited to such a configuration. A configuration in which a powdery desiccant is used as the temperature distribution uniforming means and is spread over a range larger than the display area 21 a and fixed to the inner surface of the sealing substrate 22 may be used.

  In the second embodiment, four desiccants 26 to 29 are used. However, the number of desiccants is not limited to “4”, and the number of desiccants is not “4” depending on the size of the organic EL panel 20. The present invention is also applied to a configuration using a plurality of desiccants.

  In the third embodiment, the desiccant 23A is smaller than the desiccant 23 used in the first embodiment, but the desiccant 23A is larger than the display area 21a in the same manner as the desiccant 23. A thing may be used.

  -In the said 3rd Embodiment, although stainless steel is used as one thin metal plate, it replaces with stainless steel and this invention is applied also to the structure which uses a metal plate with larger heat conductivity than air. .

  -In the said 4th Embodiment, although the thin stainless steel 31 in which many through-holes 31a were formed in the whole is used, the shape of the through-hole 31a is not restricted circularly, and it has thin through-holes of shapes other than circular The present invention is also applicable to a configuration using stainless steel.

  In the mobile display module 1 shown in FIG. 8, the number of organic EL panels is “3”, but the number is an example, and the present invention uses a plurality of organic EL panels other than “3”. The present invention can be applied to a mobile display module.

  In the mobile display module 1 shown in FIG. 8, three organic EL panels having the same size are used, but the present invention is also applied to a mobile display module using a plurality of organic EL panels having different sizes. Applicable. For example, when mounted on a vehicle such as an automobile and the speedometer is displayed on the middle panel of the three organic EL panels, the middle panel is enlarged and raised in order to improve the visibility of the speedometer. Preferably, the left and right panels are made smaller and lower than the middle panel.

  In FIG. 11, a personal computer has been described as an example of an electronic device using the organic EL panel 20, but the organic EL panel 20 described in each of the above embodiments is not limited to a personal computer, such as a mobile phone or a digital camera. Applicable to various electronic devices.

1 is an exploded perspective view showing an organic EL panel according to a first embodiment. Sectional drawing which shows the organic EL panel. The disassembled perspective view which shows the organic electroluminescent panel which concerns on 2nd Embodiment. Sectional drawing which shows the organic EL panel. The disassembled perspective view which shows the organic electroluminescent panel which concerns on 3rd Embodiment. Sectional drawing which shows the organic EL panel. The disassembled perspective view which shows the organic electroluminescent panel which concerns on 4th Embodiment. The perspective view which shows the display module of the moving body using an organic electroluminescent panel. The perspective view which shows the vehicle interior part of the vehicle by which the display module is mounted. The top view which shows the display state of the display module. The perspective view which shows the personal computer as an electronic device.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Display module of a moving body, 5 ... Base plate as a panel support member, 14, 21a ... Display area, 20 ... Organic EL panel as a display panel, 21 ... Light emitting element substrate, 21a ... Display area, 22 ... Sealing substrate , 23, 23A, 26 to 29 ... desiccant, 25 ... space, 31a ... through-hole, 70 ... personal computer as electronic equipment, 220 ... pixel, 221 ... organic EL element as electroluminescence element.

Claims (10)

In a display panel comprising: a light emitting element substrate in which a plurality of pixels each having a light emitting element are arranged in a matrix; and a sealing substrate bonded to the light emitting element substrate so as to seal the plurality of pixels.
A display panel characterized in that plate-like temperature distribution uniforming means for uniforming temperature distribution is arranged over the entire display area in the space between the light emitting element substrate and the sealing substrate. The display panel according to claim 1,
The display panel according to claim 1, wherein the uniform temperature distribution means is a desiccant spread over a range larger than the display area and fixed to the inner surface of the sealing substrate. The display panel according to claim 2,
The display panel according to claim 1, wherein the desiccant is a desiccant formed in a plate shape larger than the display area. The display panel according to claim 2,
The desiccant is composed of a plurality of desiccants formed in a plate shape, and the plurality of desiccants are spread over a range larger than the display area. The display panel according to claim 1,
The temperature distribution uniforming means is composed of a desiccant formed in a plate shape fixed to the inner surface of the sealing substrate, and one thin metal plate fixed to the desiccant and larger than the display area. A display panel characterized by that. The display panel according to claim 5,
The display panel, wherein the metal plate is disposed so as to have a gap between the light-emitting element substrate. The display panel according to claim 5,
A display panel, wherein a plurality of through holes are provided in the entire metal plate. In the display panel as described in any one of Claims 1-7,
The display panel, wherein the light emitting element is an electroluminescence element. 9. A mobile display module using the display panel according to claim 1, wherein a plurality of the display panels for displaying different images are mounted side by side on a panel support member. Display module. An electronic apparatus using the display panel according to claim 1.

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