JP5189276B2 - Image display device - Google Patents

Description

  The present invention relates to an image display device.

  Usually, in an image display device that displays a color image, each picture element is composed of a plurality of pixels of different colors (RGB).

  In a general image display device, one picture element serving as an image display unit is composed of a plurality of pixels. One square pixel is composed of three types of pixels, red (R), green (G), and blue (B), and each pixel is most often a rectangle with an aspect ratio of 3: 1. ing.

  By the way, a pixel constituting an image display device using a top emission type OLED (organic light emitting diode) includes a driving circuit layer including a transistor, a planarizing film thereon, and an OLED on the planarizing film (that is, a light emitting element). In general, the light emitting element layer includes a light emitting element layer. Since the drive circuit layer and the light emitting element layer need only be conductively connected through the contact holes, it is sufficient that each drive circuit in the drive circuit layer and each pixel in the light emitting element layer have a one-to-one correspondence. And the position do not need to match (for example, Patent Document 1).

  This light emitting element is usually formed by using a technique such as vapor deposition using a mask, printing using an ink jet, or transfer using a laser. However, when an OLED of a different color protrudes from a light emitting area (that is, an opening) of a certain pixel, color shift and luminance decrease occur. On the other hand, if an OLED is not formed in a part of the light emitting area, a dark spot or luminance is generated. In any case, image quality is deteriorated.

  For this reason, it is necessary to provide a sufficient gap between the light emitting regions of adjacent pixels in consideration of the positional accuracy of vapor deposition, printing, transfer, and blurring of film formation. However, since no light is emitted from this gap, the ratio of the light emitting area to the entire screen, that is, the ratio of the area of each light emitting area to the area of each pixel is reduced.

  In general, a luminance proportional to the current can be obtained in the OLED, but it is known that the smaller the current density, the lower the voltage applied to the OLED, and the longer the life of the image display device. For this reason, in order to extend the life of the image display device, it is important to increase the area where the OLED emits light in each pixel.

  FIG. 17 is a diagram illustrating the most common stripe-like pixel arrangement. Three pixels of RGB surrounded by a thick line constitute one substantially square picture element, and the picture elements are arranged in a grid pattern. That is, each region obtained by dividing a substantially square picture element into three equal parts in the left-right direction is a pixel region of each color.

  Here, if the arrangement period (picture element pitch) of picture elements in the vertical and horizontal directions is a, each pixel has a rectangular shape with dimensions of vertical a and horizontal a / 3.

  In such a pixel, the accuracy of vapor deposition, printing, and transfer (including positional accuracy and blurring of film formation), that is, the maximum error that can occur is x, in order to avoid problems due to excessive or insufficient OLED formation, The light emitting area of each pixel needs to be separated by 2x from the light emitting areas of adjacent pixels in the vertical and horizontal directions. For this reason, the emission region of one pixel is (a / 3-2x) × (a-2x) at the maximum. If the pixel pitch is 150 μm and the accuracy of vapor deposition or printing (that is, the maximum error) is 15 μm, x = 0.1a, and the aperture ratio (the ratio of the light emitting area in one pixel) is 0. 32. Therefore, even if the area of the portion that actually emits light on the screen is maximum, it is less than 1/3 of the area of the entire screen, and the remaining 2/3 or more portions do not emit light.

  In a general stripe pixel arrangement, each pixel is elongated, so that the ratio of the light emitting area occupying the screen is reduced.

  In view of the above problem, techniques for increasing the area of the light emitting portion with respect to the size of the picture element have been proposed (for example, Patent Documents 1 and 2).

  FIG. 18 is a diagram showing a pixel array according to Patent Document 1. As shown in FIG. Three pixels of RGB arranged in a delta shape surrounded by a thick line constitute one picture element. Here, if the arrangement period of picture elements in the vertical and horizontal directions is a, the dimensions of each pixel are vertical a / 2 and horizontal 2a / 3, and the shape of each pixel is closer to a square than the above-described stripe-shaped pixel arrangement. The aperture ratio also increases.

  In such a pixel, a maximum of (2a / 3-2x) × (a / 2-2x) is obtained as the light emitting area of one pixel while avoiding problems due to excessive or insufficient OLED formation, and x = 0.1a, the maximum aperture ratio is 0.42.

  FIG. 19 is a diagram showing a pixel array according to Patent Document 2. As shown in FIG. Here, the three RGB pixels adjacent to each other in the horizontal direction surrounded by a thick line constitute one picture element, but the RGB arrangement is reversed for each picture element adjacent to the left and right. . In such a configuration, it is possible to deposit two red pixels or two blue pixels adjacent to each other on the left and right across the picture element through the opening of one deposition mask. Deviation in deposition between pixels can be ignored.

  In vapor deposition, since different colors are generally vapor-deposited while shifting one vapor deposition mask, the vapor deposition areas of the respective colors must be accurately superimposed when they are shifted by a certain distance. Therefore, in the pixel arrangement shown in FIG. 19, the dimension of the vapor deposition region (vapor deposition region dimension) needs to be a horizontal a / 2 and a vertical a. At this time, each of one green pixel, two adjacent red pixels, and two adjacent blue pixels has the same deposition area size. As a green light emitting area of one pixel, a maximum of (a / 2-2x) × (a−2x) is obtained. When x = 0.1a, the maximum aperture ratio is 0.48. Can be obtained.

Japanese Patent No. 3620490 JP 2004-207126 A

  However, in the configuration proposed in Patent Document 1, as shown in FIG. 18, the pixels with the same pixel arrangement are arranged in the vertical direction, but the direction of the pixels is upside down for each pixel in the horizontal direction. Therefore, pixels of the same color are not arranged on a straight line. For this reason, for example, as shown in FIG. 20, when performing monochromatic light emission (only red light emission in FIG. 20), the light emitting pixels are not arranged in a line but arranged in a zigzag pattern in the horizontal direction. . Therefore, for example, the outline along the horizontal direction on the image is uneven, or the subject and the shooting direction often move in the horizontal direction in a general video, but the movement of the subject in such a video is awkward The trouble which becomes a thing will arise. That is, the image quality is degraded.

  In the configuration proposed in Patent Document 2, as shown in FIG. 19, for red and blue pixels, the distance between pixels of the same color is longer in the horizontal direction. Therefore, for example, as shown in FIG. 21, when red or blue monochromatic light emission (only red light emission in FIG. 21) is performed, the width of the vertical region (black line) that does not emit light is 3a / 2. It will become thick and obvious. Here, considering that the width of the picture element is a, the black line with a width of 3a / 2 is too thick and unacceptable in terms of image quality. That is, the image quality is degraded.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an image display apparatus capable of extending the life by improving the aperture ratio without causing deterioration in image quality.

In order to solve the above-mentioned problem, the invention of claim 1 is an image display device, comprising a plurality of pixel circuits arranged in a grid pattern, wherein each pixel circuit corresponds to each pixel. A first pixel circuit that receives each pixel signal and drives the first light emitting element, a second pixel circuit that drives the second light emitting element, and a third pixel circuit that drives the third light emitting element are arranged in units of pixels, A circuit layer in which the first to third light emitting elements included in the plurality of picture element circuits are arranged in a grid pattern; and the first light emitting element, the second light emitting element, and the circuit layer. A plurality of picture element portions each including the first light emitting element, the second light emitting element, and the third light emitting element, which are arranged in pixel units and are arranged adjacent to each other, are arranged adjacent to each other in a lattice shape, The first light emitting element, the second light emitting element And the long sides of the outer periphery of one and the other light emitting elements adjacent to each other in one direction among the third light emitting elements are in contact with each other over the entire length, and the first light emitting element, the second light emitting element, and the third light emitting element An element layer in which light emitting elements are regularly arranged on a plurality of straight lines along the one direction, the first pixel circuit of the circuit layer, and the first light emitting element of the element layer are electrically connected, and the circuit A contact portion electrically connecting the second pixel circuit of the layer and the second light emitting element of the element layer, and electrically connecting the third pixel circuit of the circuit layer and the third light emitting element of the element layer; The first light emitting element, the second light emitting element, and the third light emitting element are each arranged in a lattice shape, the one direction being an element arrangement direction, and a rectangular shape among the plurality of picture element portions Included in four adjacent pixel elements A quadrangle formed by connecting four light-emitting elements of the same type among the first light-emitting element, the second light-emitting element, and the third light-emitting element is defined as a first quadrangle, A quadrangle formed by connecting four pixel circuits of the same type among the first pixel circuit, the second pixel circuit, and the third pixel circuit included in four pixel element circuits arranged adjacently in a rectangular shape. In the case of the second quadrangle, the element arrangement direction is inclined with respect to a predetermined one side of the first quadrangle by an angle formed by one side corresponding to the predetermined one side and a diagonal line in the second quadrangle. In this case, the corners formed by the long side and the short side of the outer periphery of each of the pixel parts are two corners located on the diagonal line along the element arrangement direction in the outer periphery of the pixel circuit. And the contact portion is Two corners arranged at one end and the other end of the short side of the first light emitting element are arranged in the lattice shape of the first pixel circuit along the long side of the picture element unit. Two corners that overlap the long side and are located at one end and the other end of the short side of the second light emitting element overlap the long side of the lattice of the second pixel circuit, and one end of the short side of the third light emitting element. The two corners located at the other end overlap with the grid-like long sides of the third pixel circuit .

  The invention of claim 2 is the image display device according to claim 1, wherein each of the light emitting elements has a substantially hexagonal opening.

  The invention according to claim 3 is the image display device according to claim 1, wherein each of the light emitting elements has a substantially pentagonal opening.

The invention of claim 4 is the image display device according to any one of claims 1 to 3, wherein the first light emitting element, the second light emitting element, The third light emitting elements are arranged in a delta shape.

  In this specification, an image area as an intangible object in which a single color constituting an image is expressed by pixels of a plurality of colors (for example, RGB) is referred to as a “picture element”, while an image is displayed on an image display device. In order to reproduce the color of one point constituting the, a region as a tangible object formed by light emitting elements of a plurality of colors (for example, RGB) is referred to as a “picture element portion” and is appropriately used.

  According to the first aspect of the present invention, the aperture ratio can be improved without degrading the image quality by inclining the arrangement of the picture element portions and making the arrangement of the picture element portions and the light emitting elements of the respective colors into a lattice shape. Longer service life can be achieved.

  According to the second aspect of the present invention, since the aperture ratio of each light emitting element is substantially hexagonal, the aperture ratio can be further improved, so that the lifetime can be further increased.

  According to the third aspect of the present invention, since the aperture ratio of each light emitting element is made substantially pentagonal, the aperture ratio can be further improved, so that the lifetime can be further extended.

  According to the fourth aspect of the present invention, the plurality of light emitting elements included in each picture element are arranged in a delta shape so that the plurality of light emitting elements constituting one picture element portion are more closely packed. Since they are arranged, one point color in the image can be faithfully reproduced as one point color by light emission of one picture element unit. That is, the image quality can be further improved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<Embodiment>
FIG. 1 is a diagram illustrating a schematic configuration of an image display system 1 including an image display apparatus according to an embodiment of the present invention.

  The image display system 1 is a system in which an image signal relating to a moving image or a still image transmitted from the broadcasting station 2 or the like is received by the mobile phone 10 and the moving image or the still image is reproduced by the mobile phone 10.

  In addition, as a moving image or a still image related to an image signal transmitted from the broadcasting station 2, each pixel is composed of a plurality of pixels and a plurality of pixel elements as in the pixel and pixel arrangement shown in FIG. The image etc. which were arranged in the grid | lattice form are mentioned. That is, a plurality of picture elements are arranged in a matrix by being arranged on a plurality of rows and a plurality of columns substantially orthogonal to each other. Hereinafter, an example in which the mobile phone 10 receives an image signal related to an image having a picture element and a pixel array as shown in FIG. 17 and reproduces the image will be described.

  The mobile phone 10 is a portable electronic device that includes a display control unit 100 and a display unit 200, and also functions as an image display device that displays various images including moving images on the display unit 200.

  The display control unit 100 is a part that controls image display on the display unit 200 based on an image signal received by the mobile phone 10.

  The display unit 200 includes, for example, an organic EL display (organic electroluminescence display) having a substantially rectangular outline, and a driver unit to which pixel signals and control signals supplied from the display control unit 100 are input. It is.

  An organic EL display is a display (self-luminous image display device) having a self-luminous light emitting element that emits light by flowing current through an organic material. The organic EL display has a plurality of light-emitting elements arranged in a lattice pattern, and controls the data signal line for supplying the pixel signal to each pixel and the timing for supplying the pixel signal to each pixel through the data signal line. The scanning signal lines for supplying the scanning signals to be supplied are crossed so that the data signal lines and the scanning signal lines are substantially orthogonal to each other.

  On the other hand, the driver means is electrically connected to the data signal line and is electrically connected to the scanning signal line and an X driver (data driver) for controlling the timing of supplying the pixel signal to the data signal line, A Y driver (line driver) for controlling the timing of supplying the scanning signal to the scanning signal line. In the mobile phone 10 according to the present embodiment, for example, the X driver is disposed along the short side of the organic EL display, and the Y driver is disposed along the long side of the organic EL display.

  FIG. 2 is a cross-sectional view illustrating a cross-sectional structure of an organic EL display. The organic EL display has a large number of pixels (sub-pixels) arranged. In FIG. 2, focusing on one pixel, the organic EL element that is a light emitting element and the light emission of the light emitting element for each pixel. A circuit (pixel circuit) to be controlled is shown. In addition, here, the organic EL display is, for example, a so-called top emission type, and in the following description, the organic EL display is a top emission type.

  As shown in FIG. 2, for example, a circuit layer 202 and a wiring pattern 203 on which a pixel circuit (here, a TFT circuit) including various transistors is formed are stacked on a glass substrate 201, and the circuit layer 202 and the wiring pattern 203 are stacked. A planarizing film 204 is laminated on the substrate. On the planarizing film 204, an element layer 208 in which an organic EL element is formed by sandwiching an organic layer 207 between the anode and cathode electrodes 205 and 206 is laminated. The pixel circuit of the circuit layer 202 and the organic EL element of the element layer 208 are conductively connected by a contact portion (connection portion) 209 so as to penetrate the planarization film 204.

  Thus, the pixel circuits are arranged in units of pixels, and each pixel circuit receives each pixel signal corresponding to each pixel constituting the image and drives each light emitting element.

  FIG. 3 is a schematic view illustrating the arrangement of the pixel part PS and the openings (pixels) of the light emitting elements PSr, PSg, and PSb in the element layer 208 of the display unit 200, and is an arrangement viewed from the front side of the organic EL display. Indicates the state. In general, tens of thousands to millions of pixels are arranged on the display unit 200. In FIG. 3, the number of pixels is reduced, and the pixel arrangement is simply shown. Further, a portion expressing one point on an image formed by each one light emitting element (that is, three light emitting elements) of red (R), green (G), and blue (B) (a portion surrounded by a thick line in FIG. 3). Is referred to as a “picture element part”, and one point on an image formed by one pixel (ie, three pixels) of RGB is referred to as a “picture element”.

  As shown in FIG. 3, the element layer 208 includes a large number of light emitting elements PSr that emit R light, light emitting elements PSg that emit G light, and light emitting elements PSb that emit B light.

  Each light emitting element PSr, PSg, PSb has an opening (pixel) whose outline is substantially rectangular, and the light emitting elements PSr, PSg, PSb are arranged in this order on one side of the rectangular outline of the organic EL display. They are arranged in rows along a predetermined direction inclined by a predetermined angle. Referring to FIG. 3, each light emitting element PSr, PSg, PSb is inclined by 45 degrees with respect to the side along the horizontal direction (X direction) in FIG. 3 (hereinafter referred to as “oblique direction”). Are arranged in rows. Then, the RGB pixel rows (A row, B row, C row,...) Along the diagonal direction are arranged so as to be spread out spatially from the upper left to the lower right in FIG.

  More specifically, in each pixel column along the oblique direction, the long side of the opening of the light emitting element PSr and the long side of the opening of the light emitting element PSg are adjacent over the entire length, and the opening of the light emitting element PSg The long side and the long side of the opening of the light emitting element PSb are adjacent over the entire length, and the long side of the opening of the light emitting element PSb and the long side of the opening of the light emitting element PSr are adjacent over the entire length. .

  The “predetermined angle” referred to here is a predetermined point of four picture elements arranged in a rectangular shape adjacent to each other among a plurality of picture elements constituting an image to be reproduced by the image display device, for example, 4 In the quadrilateral connecting the barycentric points of two picture elements, this corresponds to the angle formed by one side (here, one side along the horizontal direction) corresponding to one side of the rectangular outline of the organic EL display and a diagonal line. In other words, in the present embodiment, the position of the center of gravity of one picture element (reference position), and advance from the reference position by one picture element in the horizontal direction (X direction) and one picture element in the vertical direction (Y direction). The line of the pixel part PS and the pixel line are inclined with respect to the line along the horizontal direction by an angle formed by a straight line connecting the position of the center of gravity of the picture element and a straight line along the horizontal direction (X direction). It has been.

  Further, from the viewpoint of specifying the position of the picture element by the XY address in the system, the address of one picture element (reference address) is shifted from the reference address by one picture element in the right direction and one picture element in the upward direction. The column of pixel portions PS and the pixel column are inclined with respect to the line along the horizontal direction by an angle formed by a straight line connecting the addresses and a straight line along the horizontal direction (X direction).

  In addition, since one picture element part PS is formed by three light emitting elements PSr, PSg, and PSb arranged in a line in the order of RGB along the oblique direction, as a result, the picture element part PS is also arranged in RGB. Similar to the pixel columns (A column, B column, C column,...), The pixels are sequentially arranged in the spatial direction along the diagonal direction. Then, the rows of picture element parts PS (A ′ row, B ′ row, C row ′...) Along the diagonal direction are arranged so as to be spread sequentially in the space from the upper left to the lower right in FIG. It has been.

  As described above, the row of pixel parts PS and the pixel row are inclined by a predetermined angle with respect to one side of the rectangular outline of the organic EL display, but the positions of the centers of gravity of the plurality of picture element parts PS are vertical and horizontal. Rows and columns arranged at equal intervals along the direction are formed. That is, as shown in FIG. 3, the positions of the center of gravity Gps of the plurality of picture element portions PS are arranged in a lattice shape (square lattice shape) having an aspect ratio of 1: 1. Further, the positions of the centers of gravity of the light emitting elements of the same color included in the plurality of light emitting elements PSr, PSg, PSb are also arranged in a square lattice pattern. FIG. 3 illustrates the center of gravity Gr of the light emitting element PSr. That is, along the lines parallel to the vertical and horizontal directions of the rectangular outline of the organic EL display, the positions of the barycentric points of the plurality of picture element portions PS and the barycentric points of the light emitting elements of the same color are arranged in a square lattice pattern. It is arranged.

  From another viewpoint, among the light emitting elements of each color, a rectangular shape connecting predetermined positions (for example, the positions of the centers of gravity of the four light emitting elements) of four light emitting elements arranged in a rectangular shape adjacent to each other. Of the four sides, two sides in the upper and lower horizontal directions are parallel to the horizontal direction of the rectangular outline of the organic EL display, and two sides in the left and right vertical directions are perpendicular to the vertical direction of the rectangular outline of the organic EL display. Parallel.

  Here, when the arrangement period (picture element pitch) of picture elements in the vertical and horizontal directions is a, the long side of each pixel is a / √2 and the short side is √2a / 3. Then, assuming that the accuracy of vapor deposition, printing and transfer (including positional accuracy and blurring of film formation), that is, the maximum error that can be generated, is x, The light emitting area needs to be separated by 2x from the light emitting areas of adjacent pixels in the vertical and horizontal directions. For this reason, the emission region of one pixel is {(√2a / 3) -2x} × {(a / √2) -2x} at maximum. If the pixel pitch is 150 μm and the accuracy of deposition or printing (that is, the maximum error) is 15 μm, x = 0.1a and the maximum aperture ratio is 0.413. That is, the aperture ratio is significantly higher than the aperture ratio 0.32 of the striped pixel arrangement shown in FIG. Note that here, since the shape of each opening (pixel) is closer to a square compared to the stripe-shaped pixel array shown in FIG. 17, the aperture ratio of each light emitting element is improved. Note that, in the pixel region, there is a region that originally does not emit light, such as a portion where the contact portion 209 is formed, but in this specification, a simplified pixel in which almost the entire pixel region emits light is considered. .

  Here, the positional relationship between the light emitting elements PSr, PSg, PSb in the element layer 208 and the pixel circuits MSr, MSg, MSb in the circuit layer 202 will be described.

  The pixel array of the element layer 208 and the pixel circuit array of the circuit layer 202 may be the same, but the pixel circuit array of the circuit layer 202 is preferably changed as appropriate in accordance with the pixel array of the element layer 208.

  FIG. 4 is a diagram schematically showing the arrangement of the picture element portion PS and the light emitting elements PSr, PSg, and PSb in the element layer 208, and is a diagram obtained by extracting a part of FIG.

  FIG. 5 is a schematic view illustrating the arrangement of the pixel circuits MSr, MSg, MSb and the pixel circuit group (picture element circuit unit) MS corresponding to the picture elements in the circuit layer 202 of the display unit 200, and is a front view of the organic EL display. The arrangement state seen from the side is shown. FIG. 5 shows an arrangement of the pixel circuit portion MS and the pixel circuits MSr, MSg, MSb corresponding to the arrangement of the pixel portion PS and the light emitting elements PSr, PSg, PSb shown in FIG. In FIG. 5, the outline of the picture element circuit portion MS is indicated by a thick broken line, and the outlines of the pixel circuits MSr, MSg, MSb are indicated by broken lines. The arrangement of the picture element circuit portion MS and the pixel circuits MSr, MSg, MSb is similar to the stripe-like picture element arrangement and the pixel arrangement shown in FIG.

  FIG. 6 is a schematic view of the positional relationship between the light emitting elements PSr, PSg, and PSb and the pixel circuits MSr, MSg, and MSb when the display unit 200 is viewed from the front side of the organic EL display. In FIG. 6, the arrangement of the picture element portion PS and the light emitting elements PSr, PSg, PSb shown in FIG. 4 indicated by solid lines and the picture element circuit portion MS and pixel circuit MSr shown in FIG. 5 indicated by broken lines. , MSg, and MSb are superimposed on each other. In addition, the arrangement of contact portions (connection portions) 209 that electrically connect each light emitting element PSr, PSg, PSb and each pixel circuit MSr, MSg, MSb in a pixel unit is also indicated by hatched circles.

  Here, as shown in FIGS. 4 and 5, the arrangement of the pixel parts PS and the light emitting elements PSr, PSg, and PSb in the element layer 208, and the pixel circuit part MS and the pixel circuits MSr, MSg, It differs from the sequence of MSb. Therefore, as shown in FIG. 6, in each pixel circuit unit MS, the position of the contact unit 209 with respect to the R color pixel circuit MSr, the position of the contact unit 209 with respect to the G color pixel circuit MSg, and the B color pixel circuit The positions of the contact portions 209 with respect to the MSb are different from each other. With such a configuration, the pixel circuits MSr, MSg, MSb of the circuit layer 202 and the light emitting elements PSr, PSg, PSb of the element layer 208 can be conductively connected in a one-to-one correspondence.

  FIG. 7 is a diagram illustrating a state in which the light emission pattern when the display unit 200 emits monochromatic light is viewed from the front of the display unit 200. FIG. 7 shows a light emission pattern when the R light emitting element PSr emits light without causing the GB light emitting elements PSg and PSb to emit light in the pixel array shown in FIG. The pixels of the light emitting element PSr are outlined, and the pixels of the light emitting elements PSg and PSb that are not emitting light are shown in black.

  As shown in FIG. 7, the width of the black line formed by the region that does not emit light is as narrow as about ½ of the width of the thinnest line by monochromatic light emission. The width of the black line is sufficiently narrow compared to the width of the black line in the stripe-shaped pixel array shown in FIG. 17 being about 2/3 of the width of the thinnest line by monochromatic light emission. ing. That is, an improvement in aperture ratio and an improvement in image quality are achieved.

  FIG. 8 is a diagram showing an image display example in which vertical lines and horizontal lines due to light emission of three colors of RGB intersect, and fine lines can be clearly reproduced as shown in FIG.

  By the way, when each pixel of the organic EL element is formed by the vapor deposition process, it is common to perform the vapor deposition process for each color while sequentially shifting the metal mask provided with the opening corresponding to the shape of the pixel of each color. In the striped pixel arrangement shown in FIG. 17, pixels of the same color are arranged close to each other in the vertical direction, so that the lower limit of the separation distance (minimum line width) between the openings is limited from the viewpoint of securing the strength of the metal mask. Limited. For this reason, the existence of the minimum line width opens a separation distance between pixels arranged in the vertical direction, resulting in a decrease in aperture ratio.

  On the other hand, in the pixel array of the element layer 208 according to the embodiment of the present invention, pixels of the same color are not relatively close to each other, so that the minimum line width of the metal mask can be increased. Therefore, it is possible to eliminate the decrease in the aperture ratio due to the influence of the minimum line width of the metal mask, and it is effective for further improving the deposition accuracy (ie, increasing the aperture ratio) by securing the strength of the metal mask and preventing deformation. .

  As described above, in the mobile phone (that is, the image display device) 10 according to the embodiment of the present invention, the arrangement of the picture element parts PS is tilted on the display unit 200. The light emitting elements PSr, PSg, and PSb are arranged in a square lattice pattern. With such a configuration, the aperture ratio of each light emitting element PSr, PSg, PSb is improved, so that the voltage applied to the organic EL element can be lowered. In addition, since the pixels of each color are arranged in a straight line along the vertical and horizontal directions, the contours along the vertical and horizontal directions on the image are not uneven, and the movement of the subject in the video is awkward There is no inconvenience such as becoming. Furthermore, since the interval between the pixels in the pixel array of each color is narrow, the width of the black line that causes a reduction in image quality can also be reduced. Therefore, the lifetime can be extended by improving the aperture ratio without degrading the image quality.

<Modification>
As mentioned above, although embodiment of this invention was described, this invention is not limited to the thing of the content demonstrated above.

  For example, in the above embodiment, the outline shape of the opening (pixel) of each light emitting element PSr, PSg, PSb is substantially rectangular. However, the present invention is not limited to this. For example, the opening of each light emitting element PSr, PSg, PSb If the contour shape of the portion (pixel) is made substantially hexagonal or substantially pentagonal, the aperture ratio of each light emitting element PSr, PSg, PSb can be further improved, and the life of the image display device can be further extended. it can. More strictly, the outline shape of the light emitting region of the organic layer 207 in the element layer 208 may be a substantially hexagonal shape or a substantially pentagonal shape.

  FIG. 9 shows an arrangement of picture element portions (portions surrounded by thick lines) and light emitting device openings (portions surrounded by solid lines) when the contour shape of the openings (pixels) of the respective light emitting elements is a hexagon. It is the schematic diagram which illustrates this, and has shown the arrangement | sequence state seen from the front side of the organic electroluminescent display.

  In the arrangement of the light emitting elements shown in FIG. 9, the ratio of the light emitting region in each light emitting element, that is, the aperture ratio varies depending on the size of the inner angle of the hexagon that defines the contour shape, and all the inner angles of the hexagon are 120 degrees. In such a case, the aperture ratio becomes maximum. When all the internal angles of the hexagon are 120 degrees, if the pixel pitch is 150 μm and the accuracy of vapor deposition or printing (that is, the maximum error) is 15 μm, the aperture ratio of each light emitting element is 0. 435.

  FIG. 10 shows an arrangement of picture element portions (portions surrounded by thick lines) and light emitting device openings (portions surrounded by solid lines) when the outline shape of the opening portions (pixels) of each light emitting element is a pentagon. It is the schematic diagram to illustrate, and has shown the arrangement | sequence state seen from the front side of the organic electroluminescent display.

  As shown in FIG. 10, when the outline shape of the opening of each light emitting element is a pentagon, when the pixel pitch is 150 μm and the accuracy of vapor deposition or printing (that is, the maximum error) is 15 μm, the aperture ratio of each light emitting element is The maximum is 0.424. Therefore, in such a configuration, the aperture ratio of each light emitting element is not improved as much as the contour shape of the light emitting element shown in FIG. 9 is hexagonal, but the contour shape of the light emitting element shown in FIG. 3 is rectangular. The aperture ratio of each light emitting element is improved as compared with the case.

  For example, in the above embodiment, each picture element part PS is formed by three RGB light emitting elements PSr, PSg, PSb arranged in a line along an oblique direction. However, the present invention is not limited to this. The light emitting elements PSr, PSg, and PSb whose parts are RGB may be formed by arranging different light emitting elements, such as being formed in a delta arrangement.

  FIG. 11 shows a picture element portion (portion surrounded by a thick line) PS2 and an opening portion (portion surrounded by a solid line) of the light emitting elements PSr, PSg, and PSb having a delta pixel arrangement in the element layer 208 of the display portion. It is the model which illustrates arrangement | sequence, and has shown the arrangement | sequence state seen from the front side of the organic electroluminescent display. The arrangement of the light emitting elements PSr, PSg, PSb shown in FIG. 11 is the same as that shown in FIG. 3, but the arrangement of the three light emitting elements PSr, PSg, PSb for constituting each picture element part PS2 is as follows. The way of dividing is different. Here, the two light emitting elements PSr and PSg included in each picture element part PS2 are arranged along the oblique direction.

  That is, in the above-described embodiment shown in FIG. 3, the three light emitting elements PSr, PSg, PSb included in each picture element part PS are arranged along an oblique direction. In the configuration shown in FIG. Two light emitting elements PSr and PSg included in the part PS2 are arranged along the oblique direction. Therefore, it can be said that at least two or more light emitting elements included in each of the picture element portions PS and PS2 are arranged along the oblique direction.

  By the way, as shown in FIG. 11, as shown in FIG. 3, as compared with the case where each picture element portion PS is formed by three light emitting elements PSr, PSg, PSb arranged in a line along the oblique direction. In the case where each pixel part PS2 is formed by arranging three light emitting elements PSr, PSg, PSb in a delta shape, a plurality of light emitting elements constituting one picture element part are arranged more densely. Has been. Accordingly, since the shape of one picture element portion is closer to a square, one point color in the image can be more faithfully reproduced as one point color by the light emission of one picture element portion. That is, the image quality can be further improved.

  Even in such a configuration, as described above, when the outline shape of the opening (pixel) of each light emitting element PSr, PSg, PSb is substantially hexagonal or substantially pentagonal, the opening of the light emitting element PSr, PSg, PSb is formed. The rate is improved.

  In the above embodiment, in the element layer 208, a large number of light emitting elements PSr, PSg, and PSb that emit light of three colors of RGB in a pixel unit are arranged. However, the present invention is not limited to this. For example, orange and blue A large number of light emitting elements that emit light of two colors in units of pixels may be arranged, or a large number of light emitting elements that emit light of four colors of red, green, blue, and white in units of pixels may be arranged. That is, the present invention can be applied to a structure in which a large number of light emitting elements of two or more colors are arranged and a large number of picture element portions including the light emitting elements of the respective colors are arranged.

  FIG. 12 shows the pixel portion P3 and the openings (pixels) of the red (R) green (G) blue (B) white (W) light emitting elements Pr, Pg, Pb, and Pw in the element layer 208 of the display unit 200. It is the model which illustrates arrangement | sequence, and has shown the arrangement | sequence state seen from the front side of the organic electroluminescent display.

  Here, as shown in FIG. 12, the element layer 208 includes a large number of light emitting elements Pr, Pg, Pb, and Pw that emit light of four colors of RGBW in units of pixels.

  Each of the light emitting elements Pr, Pg, Pb, and Pw has an opening (pixel) having a substantially rectangular outline, and the RGWB light emitting elements Pr, Pg, Pw, and Pb are arranged in this order in the organic EL display. A predetermined direction (lower left in FIG. 12 to upper right in FIG. 12) inclined by a predetermined angle (clockwise 45 degrees in FIG. 12) with respect to a predetermined side of the rectangular outline (side along the horizontal direction in FIG. 12) Are arranged in a row along the direction toward the head, that is, the “oblique direction”. Then, the pixel rows in the RGWB order along the oblique direction are arranged so as to be sequentially spread out from the upper left to the lower right in FIG.

  Further, one picture element portion P3 (portion surrounded by a thick line in FIG. 12) is formed by four light emitting elements Pr, Pg, Pw, and Pb arranged in a line in the order of RGWB along the oblique direction. The picture element portions P3 are arranged in a spatial order along the oblique direction, and the rows of the picture element parts along the oblique direction are arranged in a spatial order from the upper left to the lower right in FIG. Are lined up.

  As described above, the row of pixel parts P3 and the pixel row are inclined by a predetermined angle with respect to a predetermined side of the rectangular outline of the organic EL display, but the positions of the centers of gravity of the plurality of pixel parts P3 are square. They are arranged in a grid. Further, the positions of the centers of gravity of the light emitting elements of the same color included in the plurality of light emitting elements Pr, Pg, Pw, Pb are also arranged in a square lattice pattern. That is, along the lines parallel to the vertical and horizontal directions of the rectangular outline of the organic EL display, the positions of the centers of gravity of the plurality of picture element portions P3 and the positions of the centers of gravity of the light emitting elements of the same color are arranged in a square lattice pattern, respectively. Has been.

  In the above embodiment, the picture element portions PS are arranged in a lattice shape (square lattice shape) having an aspect ratio of 1: 1 in the element layer 208, but the present invention is not limited to this. For example, when the ratio of the arrangement period (vertical picture element pitch) ay in the vertical direction of the picture element part to the arrangement period (horizontal picture element pitch) ax in the horizontal direction is 1: 1.1. May be arranged in a lattice shape (rectangular lattice shape) other than the aspect ratio of 1: 1.

  However, when the arrangement period of the picture elements in the image to be reproduced by the image display device is different in the vertical direction and the horizontal direction so that the image displayed on the image display device 10 does not become an image extending in the vertical or horizontal direction. A configuration in which the horizontal picture element pitch ax and the vertical picture element pitch ay are adjusted in accordance with the arrangement period is preferable. That is, the present invention can be optimized even when the arrangement period (horizontal picture element pitch) ax in the horizontal direction of the picture elements constituting the image is different from the arrangement period (vertical picture element pitch) ay in the vertical direction. it can.

  FIG. 13 is a schematic diagram showing the arrangement of the pixel part P4 and the openings (pixels) of the light emitting elements PWr, PWg, and PWb when the vertical picture element pitch ay and the horizontal picture element pitch ax are different. The arrangement | sequence state seen from the front side of EL display is shown. The picture element portion P4 and the pixel arrangement shown in FIG. 13 are different in that the “predetermined angle” is slightly smaller than 45 degrees compared to FIG. 3, but the other configurations are substantially the same. Therefore, the description is omitted here.

  For an image related to an existing NTSC signal, the ratio of the vertical picture element pitch to the horizontal picture element pitch is about 1: 1.1, and it is preferable to employ the above configuration.

  In the above embodiment, the arrangement of the pixel circuit unit MS and the pixel circuits MSr, MSg, MSb in the circuit layer 202 is similar to the stripe-like pixel arrangement and the pixel arrangement shown in FIG. Although explained, it is not limited to this. For example, the arrangement of the pixel circuits constituting each picture element circuit section and the arrangement of the plurality of picture element circuit sections may be different. Hereinafter, an example will be described.

  FIG. 14 is a schematic view illustrating the arrangement of the pixel circuits M2r, M2g, M2b and the pixel circuit group (picture element circuit portion) M2 corresponding to the picture elements in the circuit layer, and is an arrangement seen from the front side of the organic EL display. Indicates the state. FIG. 14 shows an arrangement of the pixel circuit unit M2 and the pixel circuits M2r, M2g, and M2b corresponding to the arrangement of the picture element unit PS and the light emitting elements PSr, PSg, and PSb shown in FIG.

  In the circuit layer shown in FIG. 14, three pixel circuits M2r, M2g, and M2b each having a rectangular shape are arranged in an L shape to form an L-type pixel circuit portion M2. A plurality of picture element circuit units M2 facing in the same direction along the vertical direction are arranged adjacent to each other, and the pixel circuit units M2 adjacent to each other along the horizontal direction are turned upside down. A plurality of picture element circuit portions M2 are arranged adjacent to each other.

  FIG. 15 is a schematic view illustrating the positional relationship between the light emitting elements PSr, PSg, and PSb and the pixel circuits M2r, M2g, and M2b, and shows an arrangement state viewed from the front side of the organic EL display. In FIG. 15, the arrangement of the picture element portion PS and the light emitting elements PSr, PSg, PSb shown in FIG. 4 indicated by solid lines and the pixel element portion M2 and pixel circuit M2r shown in FIG. 14 indicated by broken lines. , M2g, and M2b are superimposed on each other. In addition, the arrangement of contact portions (connection portions) 209 that electrically connect each light emitting element PSr, PSg, PSb and each pixel circuit M2r, M2g, M2b in a pixel unit is also indicated by a circle with hatching.

  As shown in FIG. 15, in each picture element circuit portion M2, the position of the contact portion 209 relative to the R color pixel circuit M2r, the position of the contact portion 209 relative to the G color pixel circuit M2g, and the B color pixel circuit M2b By making the positions of the contact portions 209 different from each other, the pixel circuits M2r, M2g, M2b of the circuit layer 202 and the light emitting elements PSr, PSg, PSb of the element layer 208 are conductively connected in a one-to-one correspondence. Can do.

  In the above embodiment, the mobile phone 10 is described as an example of the image display device. However, as shown in FIG. 16, for example, a display unit 200A such as a notebook personal computer (PC) 10A is provided. The present invention can be applied to various image display devices in general.

  In the above embodiment, the display units 200 and 200A are described as being configured to include an organic EL display. However, the present invention is not limited to this. For example, various displays in which a circuit layer and a light emitting layer are appropriately arranged. It may be provided with.

  Note that the above embodiments and modifications may be combined as appropriate as long as no contradiction arises.

1 is a diagram illustrating a schematic configuration of an image display system according to an embodiment of the present invention. It is sectional drawing which illustrates the cross-section of an organic electroluminescent display. It is a schematic diagram which shows the arrangement | sequence of the pixel part and pixel in an element layer. It is a schematic diagram which shows the arrangement | sequence of the pixel part and pixel in an element layer. It is a schematic diagram which shows the arrangement | sequence of the pixel circuit part and pixel circuit in a circuit layer. It is a figure which shows typically the positional relationship of a light emitting element and a pixel circuit. It is a figure which shows the light emission pattern at the time of making it emit monochromatic light. It is a figure which shows the example of a display of the horizontal and vertical crossing line by light emission of RGB 3 colors. It is a schematic diagram which shows the pixel part and pixel arrangement | sequence which concern on a hexagonal opening part. It is a schematic diagram which shows the arrangement | sequence of the pixel part and pixel which concern on a pentagonal opening part. It is a schematic diagram which shows the arrangement | sequence of the pixel part which consists of a delta pixel arrangement | sequence. It is a schematic diagram which shows the pixel arrangement | sequence of RGBW4 color in an element layer. It is a schematic diagram which shows the arrangement | sequence of the pixel part and pixel from which the vertical and horizontal arrangement pitch differs. It is a schematic diagram which shows the arrangement | sequence of the pixel circuit part and pixel circuit in a circuit layer. It is a figure which shows typically the positional relationship of a light emitting element and a pixel circuit. It is a figure which shows schematic structure of the image display apparatus which concerns on a modification. It is a figure which shows a general striped pixel arrangement. It is a figure which shows the pixel arrangement | sequence which concerns on patent document 1. FIG. It is a figure which shows the pixel arrangement | sequence which concerns on patent document 2. FIG. It is a figure which shows the monochromatic light emission state in the pixel arrangement | sequence which concerns on patent document 1. FIG. It is a figure which shows the monochromatic light emission state in the pixel array which concerns on patent document 2. FIG.

Explanation of symbols

1 Image Display System 10 Mobile Phone (Image Display Device)
10A notebook computer (image display device)
200, 200A Display unit 202 Circuit layer 208 Element layer P3, P4, PS, PS2 Picture element unit Pr, Pg, Pb, Pw, PSr, PSg, PSb, PWr, PWg, PWb Light emitting element

Claims (1)

An image display device,
A first pixel circuit and a second light emitting element, each including a plurality of picture element circuits arranged in a grid pattern, wherein each pixel circuit receives each pixel signal corresponding to each pixel and drives the first light emitting element; The second pixel circuit for driving the pixel and the third pixel circuit for driving the third light emitting element are arranged in a pixel unit, and the first to third light emitting elements included in the plurality of pixel circuits are arranged in a grid pattern. Circuit layer,
The first light-emitting element, the second light-emitting element, the first light-emitting element, the second light-emitting element, and the third light-emitting element that are provided on the circuit layer, are arranged in units of pixels, and are adjacent to each other. And a plurality of picture element portions each including the third light emitting element are arranged adjacent to each other in a lattice shape , and are adjacent to each other in one direction of the first light emitting element, the second light emitting element, and the third light emitting element. The long sides of the outer periphery of one and the other light-emitting elements are in contact with each other over the entire length, and the first light-emitting element, the second light-emitting element, and the third light-emitting element are regularly arranged on a plurality of straight lines along the one direction. An element layer aligned with
Electrically connecting the first pixel circuit of the circuit layer and the first light emitting element of the element layer, and electrically connecting the second pixel circuit of the circuit layer and the second light emitting element of the element layer; A contact portion that electrically connects the third pixel circuit of the circuit layer and the third light emitting element of the element layer,
The first light emitting element, the second light emitting element, and the third light emitting element are each arranged in a lattice pattern,
The first light emitting element, the second light emitting element, and the third light emitting element included in four of the plurality of picture element portions arranged adjacent to each other in a rectangular shape among the plurality of picture element portions with the one direction as an element arrangement direction. A quadrangle formed by connecting four light emitting elements of the same type among the elements is defined as a first quadrangle, and the first pixel included in the four picture element circuits arranged adjacent to each other in a rectangular shape among the plurality of picture element circuits. When a square formed by connecting four pixel circuits of the same type among the pixel circuit, the second pixel circuit, and the third pixel circuit is a second square, the element arrangement direction is the first square. The long side and the short side of the outer periphery of each of the picture element parts when tilted by an angle formed by a diagonal line and a side corresponding to the predetermined side in the second quadrangle with respect to the predetermined one side The corner formed by is out of the outer periphery of the pixel circuit. The first light-emitting element overlaps two corners located on the diagonal along the element arrangement direction, and the contact part is disposed at an end of the picture element part along a long side of the picture element part. Two corners located at one end and the other end of the short side of the element overlap with the grid-like long side of the first pixel circuit, and two corners located at one end and the other end of the short side of the second light emitting element. Part overlaps the grid-like long side of the second pixel circuit, and two corners located at one end and the other end of the short side of the third light emitting element overlap the grid-like long side of the third pixel circuit An image display device characterized by that.

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