JP2005216582A - Organic el panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve problems wherein, for an organic EL panel with a circular polarization plate mounted on a sealing plate by means of adhesion or attachment, the circular polarization plate must be mounted on every organic EL panel so that an attachment process for the circular polarization plate is necessary for its manufacturing process and a cost is increased by that portion; and the circular polarization plate causing increase of the thickness of the organic EL panel becomes an obstacle in thinning a display unit. <P>SOLUTION: In this organic EL panel comprising a support substrate, an organic EL element formed on the support substrate and composed by catching an organic layer having at least a luminescent layer by a positive electrode and a negative electrode, and a sealing member covering the organic EL element, at least either of the support substrate and the sealing member has a circular polarization function for preventing light entered from the outside of the organic EL panel and reflected in the inside of the organic EL element from being transmitted to the outside of the organic EL panel. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  According to the present invention, an organic EL (electroluminescence) element formed by sandwiching an organic layer including at least a light emitting layer by a pair of translucent electrodes, at least one of which is disposed on a support substrate, covers the organic EL element. The present invention relates to an organic EL panel formed by bonding a stop member to the support substrate.

  Since the organic EL panel 2 as a display using the organic EL element 1 is a self-luminous element, it does not require backlight illumination, and therefore can be thinned, has a wide viewing angle, and is suitable for a large display panel. Since then, practical application has been promoted.

  The organic EL element 1 includes an anode (transparent electrode) 3 made of a light-transmitting conductive material such as ITO (indium tin oxide), and a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer from the anode 3 side. And an organic layer (an organic layer having at least a light-emitting layer) 4 composed of an electron injection layer and a cathode (back electrode) 5 composed of a conductive material such as aluminum (Al) are sequentially stacked on the support substrate 6. It is what The organic EL element 1 is covered with a concave sealing plate 7 as a sealing member, and the support substrate 6 and the sealing plate 7 are airtight with a sealing agent 8 made of, for example, an ultraviolet curable adhesive. Are joined together.

  Since the organic EL element 1 configured as described above has a very thin film thickness, light incident from the outside of the organic EL panel (external incident light) reaches the cathode 5. The cathode 5 is made of a conductive metal material such as aluminum, and the electrode surface formed by vapor deposition or the like is smooth. Therefore, the external incident light reaching the cathode 5 is reflected by the cathode 5 and emitted to the outside of the organic EL panel 2. Then, the external scenery is reflected, and the external scenery and the display overlap, so that the display becomes difficult to see.

  Therefore, as in the organic EL panel shown in FIG. 3, the reflection of external light is prevented by providing the circularly polarizing plate 9 that changes the light in a specific turning direction on the support substrate 6 that is the light emitting surface. The circularly polarizing plate 9 is composed of a linearly polarizing plate and a retardation plate. By tilting the angle formed by the polarization axis of the linearly polarizing plate and the optical axis of the retardation plate by ± 45 degrees, right-handed or left-handed circularly polarized light is produced. Can be obtained. The right circular deflection is reflected to become a left circular deflection, and the left deflection is reflected to be a right circular deflection. That is, light (external incident light) L1 incident from the outside passes through the circularly polarizing plate and becomes right-turning or left-turning circular deflection, and when reflected by the back electrode 5, it becomes circularly polarized light in the reverse direction and becomes organic. Progress toward the outside of the EL panel 2. Since the external incident light L1 reflected by the back electrode 5 is circularly polarized in the direction opposite to the incident light, the circularly polarizing plate 9 proceeds to the outside of the organic EL panel 2 without transmitting the reflected light. Blocks and prevents reflection of external light due to reflection.

When the circularly polarizing plate 9 is not installed, external light is reflected by the cathode 5 in the non-display area, and incident light is emitted from the non-display area, so that the display contrast is lowered. Furthermore, as a result of the external scenery being reflected as it is, when the organic EL element 1 performs pattern display or matrix display, the display overlaps with the external scenery, and the display is very difficult to see. Therefore, when the circularly polarizing plate 9 is installed as described above, the light reflected by the cathode 5 is blocked by the circularly polarizing plate, so that the external scenery is not reflected in the display, and is displayed by the organic EL element 1. Only the pattern to be noticed can be seen, and the organic EL panel 2 can be provided with high contrast and easy to see display.
Japanese Patent Laid-Open No. 8-322138

  In the organic EL panel 1 having the above-described configuration, the circularly polarizing plate 9 is provided on the support substrate 6 that is outside the organic EL panel by adhesion or adhesion. In such an organic EL panel, the circularly polarizing plate 9 must be provided for each organic EL panel 1, and the manufacturing process requires a step of attaching the circularly polarizing plate 9, which increases the cost. In addition, the circularly polarizing plate 9 that increases the thickness of the organic EL panel is an obstacle to reducing the thickness of the organic EL display.

  The present invention provides an organic EL panel that simplifies the manufacturing process and enables reduction in thickness by focusing on the above-described problems.

  In order to solve the above-described problems, the present invention provides a support substrate, an organic EL element formed on the support substrate and having an organic layer having at least a light emitting layer sandwiched between an anode and a cathode, and the organic EL element. An organic EL panel comprising: a sealing member for covering, wherein at least one of the support substrate or the sealing member is incident on the outside of the organic EL panel and reflected from the inside of the organic EL element. This is to block the permeation to.

  In addition, at least one of the support substrate and the sealing member is formed using a circularly polarizing plate.

  The present invention comprises a support substrate, an organic EL element formed by sandwiching an organic layer formed on the support substrate and having at least a light emitting layer between an anode and a cathode, and a sealing member that covers the organic EL element. With respect to the organic EL panel, the manufacturing process is simplified and the thickness can be reduced.

  The first embodiment of the present invention will be described below with reference to the accompanying drawings. The same or corresponding parts as those in the conventional example are designated by the same reference numerals, and detailed description thereof is omitted.

  FIG. 1 is a cross-sectional view showing a first embodiment of the present invention. The organic EL panel according to the first embodiment uses a support substrate 6 having a circular polarization function that blocks light (external incident light) L2 incident from the outside and reflected by the back electrode 5.

  The organic EL panel includes a support substrate 6, an organic EL element 1, and a sealing plate 7 (sealing member).

  The support substrate 6 is a circularly polarizing plate made of glass or a translucent resin material, and supports the organic EL element 1 and extracts colored light emitted from the organic EL element 1. The support substrate 6 is formed slightly larger than the sealing plate 7 so that the sealing plate 7 can be disposed.

  The organic EL element 1 is formed by sequentially stacking an anode (transparent electrode) 3, an organic layer 4, and a cathode (back electrode) 5 on a support substrate 6 by an appropriate method such as a sputtering method, a spin coating method, or a vapor deposition method. It will be.

  The organic layer 4 is formed by sequentially laminating a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer and an electron injection layer from the anode (transparent electrode) 3 side by means such as vapor deposition, and has a film thickness of 100 to 300 nm. It becomes layered. In the embodiment of the present invention, it is sufficient if it has at least a light emitting layer.

  A light-transmitting conductive material such as ITO (indium tin oxide) is used for the anode 3. The cathode 5 is made of a conductive material such as aluminum (Al).

  The sealing plate 7 is made of, for example, a glass material, is formed in a concave shape, and is disposed on the support substrate 6 with the sealant 8 interposed therebetween, so that the inside of the storage space constituted by the sealing plate 7 and the support substrate 6 The organic EL element 1 can be stored in an airtight manner.

  The external incident light L2 from the outside of the organic EL panel 2 on the support substrate 6 side becomes right circularly polarized light or left circularly polarized light when transmitted through the support substrate 6 which is a circularly polarizing plate. In the present embodiment, for example, when the external incident light L <b> 2 passes through the support substrate 6, it is assumed that right circularly polarized light is formed. The external incident light L2 that has become right circularly polarized light is reflected by the cathode 5 and becomes left circularly polarized light. The reflected light L2 that has become the left circularly polarized light is blocked from traveling to the outside by the support substrate 6 because the direction of the circularly polarized light (right circularly polarized light) of the support substrate 6 that is a circularly polarizing plate is opposite. As described above, the present invention using the support substrate having both the support function and the circular polarization function does not require a step of providing a circularly polarizing plate on the support substrate, so that an external scenery is not reflected in the display. It is possible to provide a thin organic EL panel with contrast.

  FIG. 2 is a sectional view of an organic EL panel showing a second embodiment of the present invention. The same or corresponding parts as those of the conventional example and the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The second embodiment has a structure in which light is extracted from the sealing plate 7 side using a circularly polarizing plate, and is an organic EL panel provided with a protective member 10 that covers the organic EL element 1.

  The organic EL panel has a support substrate 6, an organic EL element 1, a protective member 10, and a sealing plate 7.

  The support substrate 6 is made of, for example, glass or a resin material, and supports the organic EL element 1. The organic EL element 1 is formed by sequentially laminating an anode 3, an organic layer 4, and a cathode 5 that is a translucent electrode. The sealing plate 7 is a circularly polarizing plate formed in a concave shape. The protective member 10 prevents oxygen and moisture from entering the organic EL element 1, covers the organic EL element 1, and forms a storage space for storing the organic EL element 1 including the support substrate 6 and the sealing plate 7. It is to fill.

  When external incident light L3 from the outside of the organic EL panel 2 on the sealing plate 7 side passes through the sealing plate 7 which is a circularly polarizing plate, it becomes right circularly polarized light or left circularly polarized light. In the present embodiment, for example, when the external incident light L3 passes through the sealing plate 7, it is assumed that right circularly polarized light is formed. The external incident light L3 that has become right circularly polarized light is reflected by the anode 3 and becomes left circularly polarized light. Since the externally incident light L3 that has become the left circularly polarized light is opposite to the direction of the circularly polarized light (right circularly polarized light) of the sealing plate 7 that is a circularly polarizing plate, the sealing plate 7 causes the organic EL panel 2 to be exposed to the outside. Progress is blocked. As described above, the present invention using the sealing plate having both the sealing function and the circular polarization function prevents the external scenery from being reflected in the display, and the organic EL panel 2 can be thinned with high contrast. Is realized.

  In the embodiment of the present invention, the sealing plate is a circularly polarizing plate, but a film-like member having a circularly polarizing function may be used.

Sectional drawing of the 1st Embodiment of this invention. Sectional drawing of the 2nd Embodiment of this invention. Sectional drawing of a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Organic EL element 2 Organic EL panel 3 Anode 4 Organic layer 5 Cathode 6 Support substrate 7 Sealing plate (sealing member)
L1, L2, L3 External incident light

Claims (2)

An organic EL panel comprising: a support substrate; an organic EL element formed on the support substrate and having an organic layer having at least a light emitting layer sandwiched between an anode and a cathode; and a sealing member covering the organic EL element. There,
At least one of the support substrate or the sealing member blocks the transmission of light incident from the outside of the organic EL panel and reflected inside the organic EL element to the outside of the organic EL panel.   The organic EL panel according to claim 1, wherein a circularly polarizing plate is used for at least one of the support substrate and the sealing member.

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