EL display device

Abstract

An EL display device capable of reducing an average film resistance of an anode in an EL device as well as displaying an image with high definition, and electrical equipment including such an EL display device are provided. A light-shielding metal film 109 is provided on an anode 108 so as to conceal gaps between the pixels. Thus, an average film resistance of the anode 108 in the EL device is reduced. Furthermore, light leakage from the gaps between the pixels can be prevented, resulting in an image display with high definition.

Description

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to an EL (electro-luminescence) display device fabricated by forming a semiconductor device (a device utilizing a semiconductor thin film; typically a thin film transistor) onto a substrate. The present invention further relates to an electrical equipment including such an EL display device as a display section. [0003] 2. Description of the Related Art [0004] Recently, a technique for forming a thin film transistor (hereinafter referred to as TFT) onto a substrate has significantly advanced, and its application to an active-matrix display device has been developed. In particular, the TFT employing a polysilicon film therein has a field effect mobility higher than that of the conventional TFT employing an amorphous silicon film, and therefore, can operate at higher speed. Thus, a control function for pixels that is conventionally performed by an external driver circuit provided at the ou...

AI Technical Summary

Benefits of technology

[0008] Accordingly, an object of the present invention is to provide an EL display device having the structure capable of lowering a film resistance of an anode in an EL device or exhibiting any corresponding advantages. Furthermore, another objective of the present invention is to provide electrical equipment having a display section which operates stably by employing such an EL display device as the display section.

[0017] As an organic material to be used as the EL layer 107, either a low-molecular type organic material or a polymer type (high-molecular type) organic material can be used. However, it is desirable to use a polymer type organic material which can be formed by a film-formation method that can be easily performed, such as a spin coating method, a printing method, or the like.

[0020] In the present application, a film resistance of the whole anode obtained by calculating an average of a film resistance for a region where a metal film 109 and the anode 108 are layered and a film resistance for only the anode (in other words, a film resistance of the whole portion electrically connected to the anode) will be referred to as the average film resistance of the anode. By providing the metal film 109 over the anode, the average film resistance in the anode can be decreased. Furthermore, the metal film 109 also functions as a light shielding film.

[0028] In the EL display device having the above-described configuration in accordance with the present invention, light emitted from the EL device passes through the counter substrate to be emitted to reach the viewer's eyes. Accordingly, the viewer can recognize an image through the counter substrate side. In this situation, one of the features of the EL display device in accordance with the present invention is that the metal film 109 having a low electrical resistivity is disposed on the anode 108 included in the EL device so that the gaps 111 between the adjacent pixel electrodes 105 are concealed by the metal film 109. This results in a decreased average film resistance of the anode in the EL device as well as prevention of light leakage from the gaps 111 between the pixel electrodes 105. Thus, an image can be displayed with clear contours between the pixels.

[0029] Thus, in accordance with implementing the present invention, an EL display device capable of having a reduced average film resistance of an anode in the EL device section as well as displaying an image with clear contours between the pixel electrodes can be provided. Furthermore, electrical equipment employing such an EL display device as a display section can be also provided.

Problems solved by technology

When a film resistance of the anode in the device section increases, the in-plane distribution of electrical potentials in the anode becomes non-uniform due to the voltage drop, thereby resulting in disadvantages such as deviations in the light intensity of the EL device.

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