An organic electroluminescence (hereinafter referred to as “organic EL”) display device has light-emitting elements corresponding to each separate pixel and displays an image by individually controlling the emission of light. Each of the light-emitting elements includes an anode, a cathode, and a layer containing an organic EL material (hereinafter also referred to as “light-emitting layer”). The light-emitting layer is sandwiched between the anode and the cathode. The injection of electrons into the light-emitting layer through the cathode and the injection of holes into the light-emitting layer through the anode cause the electrons and the holes to recombine with each other. This discharges excess energy that excites luminescent molecules contained in the light-emitting layer, and then the luminescent molecules are deexcited to emit light.
In the organic EL display device, the anode of each of the light-emitting elements is provided as a pixel electrode for each pixel, and the cathodes are provided, for example, across the plurality of pixels as a common electrode to which a common potential is applied. The organic EL display device controls the emission of light from the pixels by applying the potential of the pixel electrode for each pixel with respect to the potential of the common electrode. It should be noted that the configuration in which the cathodes are disposed across the plurality of pixels and a common potential is applied to each of the pixels may be replaced by a configuration in which common potentials are individually applied to each separate pixel.
Note here that, for high efficiency in the extraction of light, it is preferable that the pixel electrodes be made of a metal material having a high reflectivity. However, if outside light enters the organic EL display device and becomes visible by being reflected by the pixel electrodes, the viewability of a display image will be degraded. In order to prevent such outside light reflections, it is necessary to provide the organic EL display device with a circularly polarizing plate.
In general, a polarizing plate is formed by drawing polyvinyl alcohol (PVA) (for example, Japanese Unexamined Patent Application Publication No. 2015-210459).
However, such formation of a polarizing plate by drawing polyvinyl alcohol (PVA) is difficult and poses problems in terms of manufacturing cost.
Further, bendable flexible display devices have recently been under vigorous development. However, depending on its thickness and hardness, a polarizing plate suffers from stress concentration when the display device is bent, with the result that the bent part may get cloudy or cracked.