JP2006004869A - Display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device with an organic EL panel which can achieve a new look using the existing organic EL panel. <P>SOLUTION: The display device comprises the organic EL panel 1 in which the organic EL element 17 composed of an organic layer 14 having at least a light emitting layer sandwiched between a front electrode 12 and a back electrode 15 is arranged on a translucent supporting substrate 11, and the organic EL element 17 is hermetically covered with a sealing member 16; a light guide member 2 arranged before the supporting substrate 11; and a light source unit 3 making this light guide member 2 emit light. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a display device provided with an organic EL (electroluminescence) panel.

Conventionally, in a display device provided with this type of organic EL panel, for example, the organic EL panel is mounted in a vehicle meter, and various information about the vehicle is displayed to an observer by the light emitting display section of the organic EL panel. What is made to know is known (for example, refer to the following patent document 1).
JP 2003-315106 A

  In this case, the organic EL panel further includes a pair of organic light emitting layers sandwiched between a translucent front electrode made of ITO (indium tin oxide) or the like and a non-translucent back electrode made of aluminum (Al) or the like. A self-luminous display element that emits light from the organic light emitting layer sandwiched by supplying a predetermined constant current between the front electrode and the back electrode. The light-emitting display part was visually recognized by, for example, blue-green, which is the emission color of the organic light-emitting layer itself, and the background of the light-emitting display part was visually recognized by a mirror surface (metal color) which is the color tone of the back electrode itself .

However, in the case of a display device including an organic EL panel described in Patent Document 1, a light-emitting display unit that emits blue-green light and a mirror surface that forms the background of the light-emitting display unit are always visually recognized on the viewer side. Since it is a structure, the appearance of the whole display area comprised from the light emission display part and the background part which consists of mirror surfaces had to be a thing with no interest.
Therefore, the present invention is directed to providing a display device that can realize a new appearance by using an existing organic EL panel in order to cope with the above-described problems.

  In the present invention, an organic EL element in which an organic layer having at least a light emitting layer is sandwiched between a pair of electrodes is disposed on a translucent support substrate, and the organic EL element is hermetically covered with a sealing member. A display device including an EL panel, comprising: a light guide member disposed in front of the support substrate; and a light source that emits light from the light guide member.

  The light guide member may receive light from the light source, and the light reflection member may reflect light taken into the light guide member through the light receiver to the opposite side of the support substrate. And the reflection part is formed on at least a part of a facing surface facing the support substrate.

  According to the present invention, an organic EL element having at least an organic layer having a light emitting layer sandwiched between a translucent front electrode and a non-translucent back electrode is disposed on a translucent support substrate, A display device comprising an organic EL panel that hermetically covers an organic EL element with a sealing member, comprising: a light guide member disposed in front of the support substrate; and a light source that causes the light guide member to emit light. The light guide member includes a light receiving unit that receives light from the light source, and an irradiation unit that irradiates the support substrate side with the light introduced into the light guide member through the light receiving unit. The irradiation light irradiated on the support substrate side by the light passes through the support substrate and is guided to the back electrode.

  In the invention, it is preferable that the irradiation section includes an antireflection layer.

  ADVANTAGE OF THE INVENTION According to this invention, the initial objective can be achieved and the display apparatus which can implement | achieve a novel appearance using the existing organic electroluminescent panel can be provided.

(First Embodiment) A first embodiment of the present invention will be described below with reference to the accompanying drawings. FIGS. 1 to 3 show the display device according to the first embodiment of the present invention applied to, for example, a vehicle display device. FIG. 1 is a front view of the vehicle display device, and FIG. FIG. 3 is a perspective view of the organic EL panel according to the embodiment.

  1 and 2, the display device for a vehicle in the present embodiment includes an organic EL panel 1 that displays various types of information (for example, vehicle speed) related to the vehicle, and a light guide provided in parallel along the front of the organic EL panel 1. A member 2 and a light source unit 3 for illuminating the light guide member 2 are provided.

  As shown in FIG. 3, the organic EL panel 1 mainly includes a support substrate (glass substrate) 11, a front electrode 12, an insulating layer 13, an organic layer 14, a back electrode 15, and a sealing member 16. Has been.

  The support substrate 11 is a translucent flat plate member having a substantially rectangular shape.

  The front electrode 12 is formed of a light-transmitting conductive material such as ITO on the support substrate 11 by means such as vapor deposition or sputtering, and is a Japanese character display segment portion for displaying the various information. 12a, a lead part 12b formed by being drawn out from each segment, and an electrode part 12c provided at the terminal part of the lead part 12b. The electrode portion 12c group is concentrated on one side of the support substrate 11.

  The insulating layer 13 is made of, for example, a polyimide-based translucent insulating material, and is formed by means such as photolithography. The insulating layer 13 has a window portion 13a corresponding to the display segment portion 12a and a notch portion 13b corresponding to an electrode portion to be described later of the back electrode 15, and the front electrode 12 for clearly displaying the outline of the light emitting region. A window portion 13a is formed so as to slightly overlap with the peripheral edge portion of the display segment portion 12a, and is disposed so as to cover the lead portion 12b in order to ensure insulation between the front electrode 12 and the back electrode 15.

  The organic layer 14 may be any layer as long as it has at least a light emitting layer. In this embodiment, a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer are sequentially stacked by means such as vapor deposition or sputtering. For example, it emits green light. The organic layer 14 is disposed with a predetermined size so as to correspond to the place where the window portion 13a is formed in the insulating layer 13.

  The back electrode 15 is made of a non-translucent conductive material such as aluminum (Al), aluminum lithium (Al: Li), or magnesium silver (Mg: Ag), and is formed by means such as vapor deposition or sputtering. And disposed on the organic layer 14. The back electrode 15 is electrically connected to a lead portion 15 a provided on the one side of the support substrate 11 so as to be adjacent to each electrode portion 12 c in the front electrode 12. In addition, the electrode part 15b is provided in the terminal part of the lead part 15a, and the lead part 15a and the electrode part 15b are formed of the same material as the front electrode 12.

  As described above, the organic EL element 17 is obtained by sequentially laminating the front electrode 12, the insulating layer 13, the organic layer 14, and the back electrode 15 on the support substrate 11 (see FIG. 2). In the organic EL element 17, a predetermined display segment 12 a emits light by applying a predetermined constant current to the front electrode 12 and the back electrode 15.

  The sealing member 16 is formed by forming a concave portion 16a for accommodating the organic EL element 17 in a flat plate member made of, for example, a glass material by an appropriate method of sandblasting, etching treatment, or molding. The sealing member 16 is hermetically disposed on the support substrate 11 with a support portion 16b formed so as to surround the recess 16a on the support substrate 11 via an adhesive 18 made of, for example, an ultraviolet curable epoxy resin. 11 and the sealing member 16 constitute an airtight space 19 in which the organic EL element 17 is accommodated (see FIG. 2). The sealing member 16 is configured to be slightly smaller than the support substrate 11 so that the electrode portion 12c of the front electrode 12 and the electrode portion 15b of the back electrode 15 are exposed to the outside.

  The light guide member 2 is made of, for example, a translucent acrylic resin, and the outer dimension thereof is set to a rectangular shape substantially equal to the outer dimension of the support substrate 11 in the organic EL panel 1, and the longitudinal direction thereof (indicated by an arrow in FIG. 2). The cross-sectional shape along the direction orthogonal to the X direction is substantially wedge-shaped.

  The light guide member 2 is located in the upper part in FIG. 2, and an incident part (light receiving part) 21 that receives light guided from a light introduction body, which will be described later, of the light source unit 3, and the light guide member 2 through the incident part 21. In FIG. 2, a reflection part 22 that reflects the reflected light to the observer side in the direction of arrow X in FIG. 2 and an emission part 23 that emits the reflected light from the reflection part 22 to the observer side, The incident portion 21 constitutes one side surface of the light guide member 2, the reflection portion 22 constitutes a bottom surface portion of the light guide member 2, and the emission portion 23 constitutes a surface portion facing the bottom surface portion.

  In addition, since the reflection part 22 becomes an inclined surface which inclines toward the output part 23 side as it leaves | separates from the said light introduction body, the width dimension of the one side surface 24 which opposes the incident part 21 is the width dimension of the incident part 21 It will be set narrower than.

  As shown in FIG. 1, the light source unit 3 is positioned between a pair of light sources 31 and 32 whose light emitting surfaces, which will be described later, face each other, and the light emitting surfaces of these light sources 31 and 32, and is guided from the light sources 31 and 32. The light introduction body 33 disposed in the illumination path leading to the member 2 and the light from each of the light sources 31 and 32 introduced into the light introduction body 33 from the surface other than the second wall surface, which will be described later, around the light introduction body 33 The reflector 34 is configured to return the leaked light back into the light introducing body 33 even if it leaks into the light source, and a conductor 35 for supplying lighting power to the light sources 31 and 32.

  The light sources 31 and 32 are, for example, chip light emitting diodes that emit red light, and are light emitters that cause the light introducing body 33 to emit light. Further, the light emitting surfaces 31 a and 31 b of the light sources 31 and 32 are opposed to a pair of side surfaces, which will be described later, of the light introducing body 33. In the present embodiment, each of the light sources 31, 32 is turned on when an operation unit (not shown) is turned on, for example, and is not turned on when the on operation is released.

  The light introducing body 33 is made of, for example, a translucent acrylic resin, and is formed in an elongated flat plate shape having a direction along the incident portion 21 of the light guide member 2 as a longitudinal direction, and guides light from the light sources 31 and 32. It has a function as a light guide member for guiding to the optical member 2.

  Further, the light introducing body 33 is configured such that a pair of side surfaces 33a and 33b opposed along the longitudinal direction oppose the light emitting surfaces 31a and 31b of the light sources 31 and 32, respectively. That is, each side surface 33a, 33b has a function as an incident surface on which light from each light source 31, 32 emitted from each light emitting surface 31a, 31b is incident. 33c and 33d are a pair of first and second wall surfaces facing each other along a direction orthogonal to the longitudinal direction of the light introducing body 33. Of these first and second wall surfaces 33c and 33d, FIG. The first wall surface 33c located on the right side of the reflector is configured to face a bottom wall portion, which will be described later, of the reflecting plate 34, and the second wall surface 33d located on the left side of the first wall surface 33c in FIG. The light guide member 2 is configured to face the incident portion 21.

  The first wall surface 33c functions as a reflecting surface that reflects the light introduced into the light introducing body 33 through the side surfaces 33a and 33b toward the second wall surface 33d, and the second wall surface 33d includes the first wall surface 33d. It has a function as an exit surface that emits the reflected light reflected by the wall surface 33 c toward the light guide member 2 toward the incident portion 21 of the light guide member 2. The second wall surface 33d is uniformly provided with a diffuse reflection portion 33e composed of a plurality of fine groove portions, for example, so that diffuse reflection light enters the incident portion 21.

  The reflecting plate 34 is made of, for example, a metal material and has a substantially cross-sectional “U” shape. The light emitting surface 31 a of each of the light sources 31 and 32 includes a bottom wall portion 34 a and a pair of side wall portions 34 b formed integrally therewith. , 31b and the light introducing body 33 are covered.

  The conductor 35 is made of a thin or low repulsive force, for example, a polyamide-based or polyimide-based FPC (flexible printed circuit), and is arranged along the back surface of the side wall portion 34b located on the right side in FIG. The both end portions are exposed around the side wall portion 34b. The conductor 35 is formed with a conductive path (not shown) made of, for example, a copper foil pattern, and the light sources 31 and 32 are mounted on the conductive path portions exposed around the side wall 34b. The conductor 35 is held by a reinforcing member 36 made of, for example, synthetic resin located behind this.

  In such a configuration, when the light sources 31 and 32 are turned on by turning on the operation unit, light emitted from the light emitting surfaces 31a and 31b of the light sources 31 and 32 is transmitted through the pair of side surfaces 33a and 33b. The incident light is further reflected to the second wall surface 33d side through the first wall surface 33c. At this time, even if a part of the incident light is not reflected to the second wall surface 33d side and leaks to the outside from a surface other than the second wall surface 33d, the leakage light is reflected to the light introducing member 33 side by the reflecting plate 34. Since the light is re-reflected, the amount of the incident light is reflected to the second wall surface 33d without loss.

  Then, the reflected light reflected to the second wall surface 33d is emitted from the second wall surface 33d and is incident on the incident portion 21 of the light guide member 2 facing the second wall surface 33d. At this time, since the diffuse reflection part 33e is uniformly provided on the second wall surface 33d, the diffuse reflection light is incident on the incident part 21. Thus, the diffusely reflected light taken into the light guide member 2 through the incident part 21 is further diffused and reflected by the reflecting part 22 toward the emitting part 23 (in the direction of the arrow X) and from the surface of the emitting part 23 to the viewer side. It emits toward. At this time, the outgoing light emitted to the surface side of the emission part 23 is diffusely reflected twice by the diffuse reflection part 33e and the reflection part 22 in advance, so that the entire surface of the light guide member 2 has brightness. Visible as substantially uniform red light with no unevenness.

  By the way, in this embodiment, the organic EL panel 1 is disposed behind the light guide member 2 that emits red light. The organic EL panel 1 emits green light with its display segment portion 12a facing the light guide member 2 side. Since it is configured to emit, the green light emission image of the display segment portion 12a goes straight as it is (goes in the direction of the arrow X) and passes through the light guide member 2. At this time, the green transmitted light transmitted through the two light guide members corresponding to the display segment portion 12a is mixed with the red light that is the light emission color of the light guide member 2 itself, and the yellow light that is the mixed color of green and red is mixed. The light is emitted as yellow light from the surface of the light guide member 2 (light emitting portion 23) so as to emit light. As a result, the red light emitting region R1 corresponding to the non-formation region of the display segment portion 12a (the yellow emission light) is visually recognized on the viewer side so as to form the background of the yellow light emitting region R2 that is the display segment portion 12a. The

  Therefore, in the present embodiment, when the light sources 31 and 32 are turned off, the light emission color of the display segment portion 12a is green and the background has the color of the back electrode 15 of the light sources 31 and 32. As the light is turned on, the emission color of the display segment portion 12a changes from green to yellow, and the background also changes from the color of the back electrode 15 to red. That is, the light emission color of the display segment portion 12a and the background of the light emission color change simultaneously according to the turning on and off of the light sources 31 and 32, so that the appearance of the entire display area becomes interesting and at the same time the light sources 31 and 32. By turning on, it is possible to improve the attractiveness to the observer, and it is possible to realize a display device with high merchantability.

  Moreover, although this embodiment demonstrated the case where the light guide member 2 had a substantially wedge-shaped cross section, you may form the light guide member 2 in flat form, for example. In this case, it is necessary to provide a plurality of fine uneven portions on the reflecting portion 22 of the light guide member 2 which is not an inclined surface but a flat surface by electric discharge machining or the like. In particular, the fine uneven portion can be provided on at least a part of the facing surface (reflecting portion 22) facing the support substrate 11. For example, the fine uneven portion is provided in a frame shape on the outer edge portion of the facing surface. Sometimes, the red light guided into the light guide member 2 is reflected on the fine concavo-convex portion, and passes through the non-formation region of the fine concavo-convex portion as it is without hitting the reflection portion 22. The red light reflected through the concavo-convex portion is visually recognized as surrounding the green light of the display segment portion 12a in a frame shape.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIG. 4. The same or corresponding parts as those in the first embodiment described above will be denoted by the same reference numerals and detailed description thereof will be given. Description is omitted. The second embodiment is different from the first embodiment in that the light guide member 4 disposed in front of the organic EL panel 1 transmits light from the light source unit 3 to the surface side of the light guide member 4. And a reflection / transmission part 41 that reflects light from behind (the organic EL panel 1 side) and transmits the light from the reflection / transmission part 41 on the back side facing the reflection / transmission part 41. It is the point provided with the irradiation part 42 which irradiates to. A light receiving unit 43 receives light guided from the light source unit 3.

  The reflection / transmission part 41 of the light guide member 4 in the second embodiment is an inclined surface that approaches the irradiation part 42 as the distance from the light source unit 3 increases. A transparent thin film antireflection layer (AR coating) 44 obtained by vacuum deposition of magnesium fluoride or the like is provided on the back surface of the irradiation unit 42. This antireflection layer 44 is a layer that travels straight as it is without irregular reflection.

  And in this 2nd Embodiment, the red light from the light source unit 3 taken in in the light guide member 4 through the light-receiving part 43 of the light guide member 4 is reflected in the irradiation part 42 side by the reflective transmission part 41. Then, the reflected light passes through the irradiation unit 42 and the antireflection layer 44 and is irradiated to the organic EL panel 1 side. At this time, the irradiation light irradiated from the antireflection layer 44 is irradiated to the organic EL panel 1 as it is without irregular reflection.

  Further, the irradiation light is roughly classified into red light that passes through the support substrate 11 and the front electrode 12 and goes to the organic layer 14 and red light that passes through the support substrate 11 and the insulating layer 13 and goes to the back electrode 15. . Among these, the red light which goes to the organic layer 14 side mixes with the green light which the said light emitting layer (display segment part 12a) of the organic layer 14 emits, and becomes yellow light, The light guide member 4 without this yellow light being irregularly reflected. And is diffused reflected light from the surface side of the reflection / transmission part 41 and is emitted to the viewer side. On the other hand, the red light traveling toward the back electrode 15 is reflected by the back electrode 15, and the red reflected light is returned back into the light guide member 4 without being irregularly reflected and emitted from the surface side of the reflection / transmission part 41.

  Therefore, also in this embodiment, when the light sources 31 and 32 are turned off, the light emission color of the display segment portion 12a is green and the background has the color of the back electrode 15 is the light sources 31 and 32. Since the display segment portion 12a changes from green to yellow and the background also changes from the color of the back electrode 15 to red as the LED is turned on, the same effect as the first embodiment is obtained. be able to.

  In the second embodiment, the light guide member 4 has a substantially wedge-shaped cross section. However, the light guide member 4 may be formed in a flat plate shape, for example. In this case, it is necessary to provide a plurality of fine uneven portions on the reflection / transmission portion 41 of the light guide member 4 that is a flat surface instead of an inclined surface by electric discharge machining or the like.

  In each of the above embodiments, the case where the two light sources 31 and 32 are both chip-type light emitting diodes emitting red light has been described. However, the present invention is not limited to this, and the light sources 31 and 32 are respectively For example, the light sources 31 and 32 emit red light after the on-operation of the operation unit, and the light sources 31 and 32 emit blue light after a predetermined time has elapsed from this state. You may do it.

  In each of the above embodiments, the case where light is supplied to the light guide members 2 and 4 using the two light sources 31 and 32 has been described. For example, light is supplied to the light guide member using only one light source. Also good.

  In each of the above embodiments, the case where the light emission color of the display segment portion 12a and the background color thereof change by turning on the light sources 31 and 32 has been described. For example, a large amount of current flows between the front electrode 12 and the back electrode 15. Thus, only the background color may be changed without substantially changing the emission color of the display segment portion 12a by turning on the light sources 31 and 32.

  In each of the above embodiments, the example using the segment display type organic EL panel has been described. However, the present invention is not limited to this, and for example, a dot matrix type organic EL panel may be applied.

  In each of the above embodiments, the example in which the sealing member 16 is made of a glass material has been described. However, for example, the sealing member 16 may be formed of a metal material. However, in this case, in order to prevent the lead portions 12b and 15a from being short-circuited by the metal sealing member, it is necessary to include ball-shaped or columnar spacers made of an insulating material (resin or glass material) in the adhesive. .

  In each of the above-described embodiments, the sealing member 16 has a structure in which the concave portion 16a and the support portion 16b are integrally formed. However, the sealing member 16 applied to the present invention is not limited to this. For example, the sealing member 16 may be configured by a flat plate member and a spacer serving as a support portion.

1 is a front view of a display device according to a first embodiment of the present invention. It is AA sectional drawing of FIG. It is a perspective view which shows the organic electroluminescent panel by the same embodiment. It is sectional drawing of the display apparatus by 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Organic EL panel 2, 4 Light guide member 3 Light source unit 11 Support substrate 12 Front electrode 14 Organic layer 15 Back electrode 16 Sealing member 17 Organic EL element 21 Incident part (light receiving part)
22 reflection part 23 emission part 31, 32 light source 33 light introduction body 41 reflection transmission part 42 irradiation part 44 antireflection layer

Claims (4)

An organic EL element having an organic layer having at least a light emitting layer sandwiched between a pair of electrodes is disposed on a translucent support substrate, and includes an organic EL panel that hermetically covers the organic EL element with a sealing member. Display device,
A display device comprising: a light guide member disposed in front of the support substrate; and a light source that emits light from the light guide member. The light guide member includes a light receiving portion that receives light from the light source, and a reflection portion that reflects light taken into the light guide member through the light receiving portion to the side opposite to the support substrate side, The display device according to claim 1, wherein the reflection portion is formed on at least a part of a facing surface facing the support substrate. An organic EL element in which an organic layer having at least a light emitting layer is sandwiched between a translucent front electrode and a non-translucent back electrode is disposed on a translucent support substrate, and the organic EL element is sealed. A display device including an organic EL panel that is airtightly covered by a stop member,
A light guide member disposed in front of the support substrate, and a light source that emits light from the light guide member,
The light guide member includes a light receiving unit that receives light from the light source, and an irradiation unit that irradiates the support substrate side with light received in the light guide member through the light receiving unit,
The display device according to claim 1, wherein the irradiation light irradiated to the support substrate side by the irradiation unit passes through the support substrate and is guided to the back electrode. The display device according to claim 3, wherein the irradiation unit includes an antireflection layer.

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