Organic EL display device

Abstract

The invention provides an organic EL display device with a display part. The display part is obtained in such a manner that a plurality of organic EL elements are two-dimensionally arranged on a translucent support substrate to compose pixels. Each organic EL element has a first electrode, an organic EL layer and a second electrode that are laminated in order on the support substrate. Either the first electrode or the second electrode is one with translucency, while the other is a one without translucency. The non-translucent electrodes are arranged to exist only in a part of each pixel when viewed from a plane (for example, a width of the electrode is made smaller than that of a pixel). In this way, the display part transmits light through parts of the pixels where non-translucent electrodes are not arranged. In addition, to reduce the light transmission of the outer region of the display part and to make the light transmission approximate to the light transmission of the display part, a dummy electrode is disposed at the outer region.

Description

technical field [0001] The present invention relates to an organic EL display device, and particularly to a transmissive display device (see-through display) in which light can transmit through an image display portion of the display. Background technique [0002] Organic Electro-Luminescence (Organic Electro-Luminescence (hereinafter referred to as "Organic EL") display device that utilizes the light-emitting phenomenon of organic substances has higher image quality than liquid crystal displays and plasma displays, and can be further thinned. It has high brightness, Due to its excellent features such as high definition and low power consumption, the development of next-generation display devices has been progressing in recent years. For example, displays for various electronic devices such as TVs, car navigation systems, and portable terminals are being commercialized. [0003] In this organic EL display device, a light-emitting element (organic EL element) is formed by lam...

AI Technical Summary

Problems solved by technology

Alternatively, even if the resistance does not decrease, as long as an organic EL element that emits brighter light can be formed with a small current, it is difficult to obtain an organic EL material that can obtain high brightness with such a small current at this stage.

[0018] (2) On the other hand, in order to reduce the wiring resistance, it is conceivable to increase the film thickness of the transparent electrode, or to laminate an ultra-thin film of silver as a low-resistance metal on the transparent electrode, or to mix a low-resistance metal with the transparent electrode layer, etc., but Both have a trade-off relationship with the transmittance of the common electrode. If the resistance value is lowered, the transmittance will decrease. If the transmittance is to be increased, the resistance value must be increased. It is difficult to balance the display quality and the characteristics of a see-through display at the same time.

However, in this structure, even if the light is transmitted in the thin film region, it has to pass through the metal film. Since the transmittance above a certain level is not expected, it is necessary to make the cathode more than a light-transmitting thin film layer and a low-resistance thick film layer. Layer structure, so there is a problem of increased manufacturing cost

[0021] In this way, in the conventional display structure, it is difficult to balance the characteristics of see-through and display quality, and it is difficult to mass-produce displays at low cost.

[0022] In addition, in a display using transparent electrodes for both the anode and the cathode (such as the above-mentioned Patent Documents 5, 6, etc.), light will be emitted to both the front and back sides of the display, so it cannot be used in cases where it is not desirable to leak display information to the back side. middle

In addition, in the case where a display is arranged in front of an on-board instrument of an automobile as described above, the light emitted from the back side is reflected on the rear instrument, and the display of the display becomes difficult to see, or depending on the installation situation of the display, it may Causes malfunctions of devices and parts installed on the back, etc. If the light hits the back side, it may cause problems depending on the way of use

In addition, such a problem may also occur in the structure described in the above-mentioned Patent Document 4 (Japanese Unexamined Patent Publication No. 2001-148292)

[0023] Also, in the see-through display, there is a problem that a difference in transparency (light transmittance) occurs between the display portion (display area) and its peripheral area (outer area), thereby changing the appearance of the display panel.

Specifically, the display unit having a laminated structure for displaying images has lower transparency than its surroundings, and a highly transparent frame-shaped portion can be seen around the display unit.

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