Organic el panel

Abstract

Each pixel includes a region where a lower reflection film is not present. In each pixel, there is a region where a microcavity structure is formed between a counter electrode and a lower reflection film and another region where the microcavity structure is not formed. The regions differentiated in cavity length can differently enhance the peak wavelength so as to improve the viewing angle dependence. Furthermore, in each of R, G, and B light emitting pixels, the area ratio of a region where the microcavity structure is present and another region where the microcavity structure is not present can be adjusted so as to eliminate the differences caused by the microcavity structure.

1 . A pixel for use in an electroluminescent (EL) panel, the pixel comprising:
 a semi-transmissive film;   a reflective film; and   an organic EL element having a light emitting layer, the organic EL element being provided between the semi-transmissive film and the reflective film;   wherein a surface of the semi-transmissive film faces the light emitting layer.   wherein, when projected along a direction perpendicular to the surface of the semi-transmissive film, an area of the semi-transmissive film is different from a light emitting area;   wherein a microcavity region is formed between the semi-transmissive film and the reflective film where the semi-transmissive film overlaps the light emitting layer; and no microcavity region is formed where the semi-transmissive film and the light emitting area do not overlap each other.   
     
     
         2 . The pixel of  claim 1 , wherein, when projected along the direction perpendicular to the surface of the semi-transmissive film, the area of the semi-transmissive film is less than an area of the light emitting area. 
     
     
         3 . The pixel of  claim 1 , wherein the organic EL element is a red light emitting organic EL element, a green light emitting organic EL element, or a blue light emitting organic EL element;
 wherein, if the organic EL element is a red light emitting organic EL element, a ratio of the area of the semi-transmissive film to the area of the light emitting area is a first ratio;   wherein, if the organic EL element is a green light emitting organic EL element, the ratio of the area of the semi-transmissive film to the area of the light emitting area is a second ratio different from the first ratio; and   wherein, if the organic EL element is a blue light emitting organic EL element, the ratio of the area of the semi-transmissive film to the area of the light emitting area is a third ratio different from the first ratio and the second ratio.   
     
     
         4 . The pixel of  claim 3 , wherein the first ratio is smaller than the second ratio, and the second ratio is smaller than the third ratio. 
     
     
         5 . The pixel of  claim 2 , wherein the semi-transmissive film is provided at a center of the pixel. 
     
     
         6 . The pixel of  claim 1 , wherein, when projected along the direction perpendicular to the surface of the semi-transmissive film, the area of the semi-transmissive film is equal to or larger than an area of the light emitting area. 
     
     
         7 . The pixel of  claim 6 , wherein the organic EL element comprises a plurality of layers;
 one of the plurality of layers is a variable-thickness layer;   within the pixel, the variable-thickness layer has a first thickness in a first region and a second thickness in a second region; and   the first thickness is larger than the second thickness, such that the first region is a thick region.   
     
     
         8 . The pixel of  claim 7 , wherein the variable-thickness layer is a hole transport layer. 
     
     
         9 . The pixel of  claim 7 , wherein, when projected along the direction perpendicular to the surface of the semi-transmissive film, the thick region has a thick region area that is less than the area of the light emitting area. 
     
     
         10 . The pixel of  claim 9 , wherein the organic EL element is a red light emitting organic EL element, a green light emitting organic EL element, or a blue light emitting organic EL element;
 wherein, if the organic EL element is a red light emitting organic EL element, a ratio of the thick region area to the area of the light emitting area is a first ratio;   wherein, if the organic EL element is a green light emitting organic EL element, the ratio of the thick region area to the area of the light emitting area is a second ratio different from the first ratio; and   wherein, if the organic EL element is a blue light emitting organic EL element, the ratio of the thick region area to the area of the light emitting area is a third ratio different from the first ratio and the second ratio.   
     
     
         11 . This pixel of  claim 10 , wherein the first ratio is smaller than the second ratio, and the second ratio is smaller than the third ratio. 
     
     
         12 . The pixel of  claim 6 , wherein, within the pixel, the semi-transmissive film has a first thickness in a first region and a second thickness in a second region; and
 the first thickness is larger than the second thickness, such that the first region is a thick region.   
     
     
         13 . The pixel of  claim 12 , wherein, when projected along the direction perpendicular to the surface of the semi-transmissive film, the thick region has a thick region area that is less than the area of the light emitting area. 
     
     
         14 . The pixel of  claim 13 , wherein the organic EL element is a red light emitting organic EL element, a green light emitting organic EL element, or a blue light emitting organic EL element;
 wherein, if the organic EL element is a red light emitting organic EL element, a ratio of the thick region area to the area of the light emitting area is a first ratio;   wherein, if the organic EL element is a green light emitting organic EL element, the ratio of the thick region area to the area of the light emitting area is a second ratio different from the first ratio; and   wherein, if the organic EL element is a blue light emitting organic EL element, the ratio of the thick region area to the area of the light emitting area is a third ratio different from the first ratio and the second ratio.   
     
     
         15 . This pixel of  claim 14 , wherein the first ratio is smaller than the second ratio, and the second ratio is smaller than the third ratio.