Display device and electronic apparatus having a display device

A display device includes: plural sub-pixels included in a main pixel, emitting light of different colors respectively; at least three apertures arranged so as to be aligned along one direction in the sub-pixel; and an aperture defining portion defining aperture lengths so that an aperture length of an aperture other than apertures at both edge portions along the one direction is longer than an aperture length of apertures at both edge portions along the one direction in the at least three apertures.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a display device and an electronic apparatus. More particularly, the invention relates to a display device and an electronic apparatus in which a main pixel is provided with plural sub-pixels displaying different colors, and the sub-pixel is divided into plural apertures.

2. Description of the Related Art

An organic EL (Electro-Luminescence) display device does not emit light when there are foreign objects or the like in an organic EL light emitting layer. This is a phenomenon in which a leakage path is formed between electrodes due to foreign objects mixed into electrodes of a pixel and the entire pixel does not emit light. The entire pixels do not emit light also when foreign objects exist on a thin-film transistor substrate (TFT substrate) and power supply to the organic EL layer is shut off.

When the organic EL layer is formed by using a mask on the TFT substrate, it is difficult to completely exclude foreign objects. Since a region in which a leakage path is actually generated is part of the pixel, when one pixel is divided into plural sub-pixels and remaining sub-pixels without leakage emit light normally, it is expected that pixel defects are reduced.

For example, a structure in which one pixel is divided into plural regions is disclosed in JP-A-2007-286081 (Patent Document 1). That is, one pixel is divided into plural TFTs or EL elements. Accordingly, even when a leakage path is generated at any of divided regions, or even when power supply to the EL element is shut off, light emission (lighting) at other divided regions can be maintained. In this case, the light emitting area of the EL element is reduced as compared with a normal pixel, however, a complete black dot defect can be avoided.

SUMMARY OF THE INVENTION

However, in a related-art display device in which the aperture area of one main pixel is simply divided equally, when there is a defect at an aperture arranged at an edge portion, the distance from an aperture at which light emission is maintained to a light emitting region of an adjacent pixel becomes long. Accordingly, a black (non-light emitting) region becomes wide as compared with a case in which there is a defect at an aperture at the center portion, therefore, there arises a problem that the region tends to be visible as a black dot.

In view of the above, in the case where a main pixel is divided into plural aperture, it is desirable to avoid generation of difference in visibility as a non-light emitting region when a defect occurs at any aperture.

According to a embodiment of the invention, there is provided a display device including plural sub-pixels included in a main pixel, emitting light of different colors respectively, at least three apertures arranged so as to be aligned along one direction in the sub-pixel, and an aperture defining portion defining aperture lengths so that an aperture length of an aperture other than apertures at both edge portions along the one direction is longer than an aperture length of apertures at both edge portions along the one direction in the at least three apertures. Also according to the embodiment of the invention, there is provided an electronic apparatus including the display device in a main casing thereof.

In the embodiment of the invention, even when a failure occurs at a pixel corresponding to any one of the at least three apertures, distances between adjacent normal pixels can be approximately equal.

Specifically, in the embodiment of the invention, when a distance between the aperture other than apertures at both edge portions and an adjacent aperture is “a”, a distance between one of the apertures at both edge portions and one of apertures at both edge portions in a main pixel adjacent in one direction is “b”, an aperture length of one of the apertures at both edge portions along the one direction is “Le” and an aperture length of an aperture other than the apertures at both edge portions along the one direction is “Ls”, a<b is satisfied, and further, Le+a+b=Ls+2a is satisfied.

According to the above, even when a failure occurs at a pixel corresponding to any of at least three apertures, distances of normal pixels adjacent to the failure position can be approximately equal.

According to the embodiment of the invention, it is possible to provide a display device in which, in the case where the main pixel is divided into plural apertures, the difference in visibility as a non-light emitting region is not generated even when a failure occurs at any aperture to thereby realizing high yield.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Herein after, a best mode for carrying out the invention (referred to as an “embodiment” in the following description) will be explained. The explanation will be made in the following order.

2. Configuration of a pixel portion (Comparative example, Basic configuration of the embodiment, Circuit configuration)

4. Application example

1. Outline of a Display Device

FIG. 1is a schematic plan view explaining an outline of the whole configuration of a display device according to an embodiment of the invention. That is, a display device1includes a display region10provided at approximately the center of a support substrate such as a glass substrate, power supply portions20arranged at the periphery of the display region10, signal line input portions21, a scanning signal input portions24and power supply control signal input portions25.

In the display region10, plural pixel portions30are arranged vertically and horizontally in a matrix state. In the display device displaying color images, an assortment of pixel portions30corresponding to, for example, R (red), G (green) and B (blue) constitutes a display pixel.

Each pixel portion30includes a drive portion31ahaving a drive transistor. The drive transistor of the drive portion31ais made of a thin-film transistor (TFT) formed on a substrate, which drives a drive target provided in the pixel portion30by voltage application.

When the drive target in the pixel portion30is the organic EL (Electro Luminescence) layer, an electric field given to the organic EL layer corresponding to respective colors is controlled by the drive transistor. When the drive target in the pixel portion30is the liquid crystal layer, the electric field given to the liquid crystal is controlled by the drive transistor.

A power supply control line22and a scanning line23are connected to the drive transistor, and the drive transistors in the display region10are sequentially driven by the scanning signal input portions24to thereby display images.

That is, power supply voltage is supplied to a horizontal pixel row selected by the scanning line23from the power supply control line22, and display of the pixel is performed in accordance with a pixel signal inputted from the signal line input portion21in the vertical pixel column direction through a signal line26. The selection of the horizontal pixel row by the scanning lines23and the input of pixel signals from the signal lines26are synchronized to drive the display region10, as a result, images are displayed.

In order to manufacture the drive substrate1, respective layers such as a semiconductor layer and an insulating film layer are formed on the support substrate by a deposition process, for example, a CVD (Chemical Vapor Deposition) and the like, and drive elements are formed and wiring is patterned by an impurity implantation process, a photolithography process and so on.

FIG. 2is a schematic cross-sectional view explaining a configuration example of a drive transistor in a pixel portion. That is, a gate electrode Trg which is a first metal layer is formed within a glass substrate40and a semiconductor layer42is formed thereon through a gate insulating film41.

The semiconductor layer42is formed by amorphous silicon being annealed and crystallized by irradiating laser light. Over the semiconductor layer42, an n+layer is formed right and left of an etching stopper43. A source electrode Trs and a drain electrode Trd which are second metal layers are formed through the n+layer.

A passivation film44is formed on the drive transistor31, and an anode electrode51is formed through an insulating planarization film45to be formed thereon.

Furthermore, an insulating film for defining apertures46which defines apertures is formed on the anode electrode51, and an organic EL layer is formed within the aperture on the anode electrode51. Additionally, a cathode electrode52is formed on the organic EL layer over the whole surface.

2. Configuration of a Pixel Portion

Next, a configuration of a pixel portion in the display device according to the embodiment will be explained. In order to make the configuration of the pixel portion of the display device in the embodiment easily understandable, explanation will be made with a comparative example.

Comparative Example

FIG. 3is a plan view explaining the transistor structure of a pixel portion in a comparative example. InFIG. 3, a transistor structure in one main pixel corresponding to any one color of R (red), G (green) and B (blue) is shown. In the pixel portion, three drive transistors Tr-d1to Tr-d3are provided in one main pixel, and three write transistors Tr-w1to Tr-w3and three storage capacitors Cs1to Cs3are provided so as to correspond to these drive transistors.

In the main pixel, gate electrodes of the write transistors Tr-w1to Tr-w3are connected to the scanning line23in common. Also, drain electrodes of the write transistors Tr-w1to Tr-w3are connected to the signal line26in common. Additionally, drain electrodes of the drive transistors Tr-d1to Tr-d3are connected to the power supply control line22in common. Accordingly, three write transistors Tr-w1to Tr-w3and three drive transistors Tr-d1to Tr-d3operate at the same time in the main pixel.

FIG. 4is a plan view explaining apertures of the pixel portion in the comparative example. The plan view shows a layout of anode electrodes51and apertures corresponding to the transistor structure of one main pixel shown inFIG. 3. The anode electrodes51are connected to source electrodes of respective drive transistors Tr-d1to Tr-d3shown inFIG. 3through contacts. Since there are three drive transistors Tr-d1to Tr-d3in the example shown inFIG. 3, three anode electrodes51are provided so as to correspond to these transistors.

A first aperture S1, a second aperture S2and a third aperture S3are provided at regions inside the three anode electrodes51. The aperture size of the first aperture S1, the second aperture S2and the third aperture S3is determined by the insulating film for defining apertures46. Though the insulating film for defining apertures46is used as a component for determining the aperture size, a shielding film to be provided at an upper layer can be used as an aperture defining portion. Emitted light is irradiated from the respective apertures S1to S3.

In the comparative example, when the aperture size of the first aperture S1is W1, the aperture size of the second aperture S2is W2and the aperture size of the third aperture S3is W3, W1=W2=W3, that is, the respective apertures are provided with equal size.

Basic Configuration of the Embodiment

FIG. 5is a plan view explaining a transistor structure of a pixel portion in the embodiment. InFIG. 5, the transistor structure of one main pixel corresponding to any one color of R (red), G (green) and B (blue) is shown. In the pixel portion, three drive transistors Tr-d1to Tr-d3are provided in one main pixel, and three write transistors Tr-w1to Tr-w3and three storage capacitors Cs1to Cs3are provided so as to correspond to these drive transistors.

In the main pixel, gate electrodes of the write transistors Tr-w1to Tr-w3are connected to the scanning line23in common. Also, drain electrodes of the write transistors Tr-w1to Tr-w3are connected to the signal line26in common. Additionally, drain electrodes of the drive transistors Tr-d1to Tr-d3are connected to the power supply control line22in common. Accordingly, three write transistors Tr-w1to Tr-w3and three drive transistors Tr-d1to Tr-d3operate at the same time in the main pixel.

FIG. 6is a plan view explaining apertures of the pixel portion in the embodiment. The plan view shows a layout of anode electrodes51and apertures corresponding to the transistor structure of one main pixel shown inFIG. 5. The anode electrodes51are connected to source electrodes of respective drive transistors Tr-d1to Tr-d3shown inFIG. 5through contacts. Since there are three drive transistors Tr-d1to Tr-d3in the example shown inFIG. 5, three anode electrodes51are provided so as to correspond to these transistors.

The first aperture S1, the second aperture S2and the third aperture S3are provided at regions inside the three anode electrodes51. The aperture size of the first aperture S1, the second aperture S2and the third aperture S3is determined by the insulating film for defining apertures46. Though the insulating film for defining apertures46is used as the component for determining the aperture size, a shielding film to be provided at an upper layer can be used as an aperture defining portion. Emitted light is irradiated from the respective apertures S1to S3.

In the embodiment, when the aperture size of the first aperture S1, the aperture size of the second aperture S2is W2and the aperture size of the third aperture S2is W3, W2is larger than W1and W3. That is, W1, W2and W3are formed to be equal in the comparative example explained above, however, the aperture size W2provided at a position other than both edge portions is formed to be larger than the aperture sizes W1, W3arranged at both edge portions in the embodiment.

FIG. 7is a circuit diagram explaining a circuit configuration of the pixel portion in the display device according to the embodiment. In the embodiment, three apertures are provided at the main pixel and three write transistors Tr-w1to Tr-w3and three drive transistors Tr-d1to Tr-d3and three storage capacitors Cs1to Cs3are provided so as to correspond to the respective apertures.

Gate electrodes of respective write transistors Tr-w1to Tr-w3are connected to a not-shown scanning line, drain electrodes of respective write transistors Tr-w1to Tr-w3are connected to the signal line26.

Additionally, source electrodes of respective write transistors Tr-w1to Tr-w3are connected to gate electrodes of corresponding drive transistors Tr-d1to Tr-d3respectively. Drain electrodes of respective drive transistors Tr-d1to Tr-d3are connected to the power supply control line in common, to which power supply voltage is supplied. Source electrodes of respective drive transistors Tr-d1to Tr-d3are connected to anode electrodes of the organic EL light emitting layer. Cathode electrodes of the organic EL light emitting layer are grounded in common. The respective storage capacitors Cs1to Cs3are connected between gates and sources of corresponding drive transistors Tr-d1to Tr-d3.

In the above circuit configuration, when a signal is inputted to the scanning line, three write transistors Tr-w1to Tr-w3are turned on, and the signal is stored in respective storage capacitors Cs1to Cs3from the signal line26. The drive transistors Tr-d1to Tr-d3are operated in accordance with the signal, and voltage corresponding to the signal is applied to the anode electrodes of the organic EL light emitting layer. The organic EL light emitting layer emits light by the voltage.

3. Specific Example

Next, a specific example of apertures in the pixel portion will be explained. The explanation of the specific example will be made with a comparative example in order to make the embodiment easily understandable.

Comparative Example

FIG. 8is a plan view explaining a specific example of apertures in the comparative example. In the drawing, apertures of two main pixels P-1, P-2which are vertically adjacent are shown. Since the apertures of two main pixels P-1, P-2are the same, a layout of the apertures will be explained by using the main pixel P-1here.

In the main pixel P-1, three sub-pixels p1, p2and p3are provided. Each of sub-pixels p1, p2and p3emits light corresponding to one color respectively. For example, the sub-pixel p1emits light corresponding to R (red), the sub-pixel p2emits light corresponding to G (green) and the sub-pixel p3emits light corresponding to B (blue).

Respective sub-pixels p1, p2and p3are laid out so that three apertures S1, S2and S3are aligned in one direction (vertical direction in the drawing) according to corresponding colors. The aperture sizes of respective apertures S1, S2and S3are defined by an aperture defining portion K (for example, an insulating film for defining apertures or a shielding film). In the comparative example, the apertures are provided so that the aperture sizes of respective apertures S1, S2and S3are equal.

The three apertures S1, S2and S3provided at respective sub-pixels p1, p2and p3emit light at the same time so as to correspond to respective colors. That is, when light of R (red) in the main pixel P-1is emitted, light is emitted from three apertures S1to S3of the sub-pixel p1corresponding to R (red) at the same time. Similarly, when light of G (green) in the main pixel P-1is emitted, light is emitted from three apertures S1to S3of the sub-pixel p2corresponding to G (green) at the same time. Also similarly, when light of B (blue) in the main pixel P-1is emitted, light is emitted from three apertures S1to S3of the sub-pixel p3corresponding to B (blue) at the same time.

Here, a case in which a light emission failure occurs at any one of three apertures S1, S2and S3in each of the sub-pixels p1, p2and p3will be explained. The light emission failure occurs due to a failure of a transistor corresponding to each of apertures S1, S2and S3or a failure between electrodes in the organic EL light emitting layer. In the following explanation, the light emission failure caused by the failure of the transistor corresponding to the aperture or the failure of the organic EL light emitting layer will be just expressed as a light emission failure at an aperture.

For example, assume that the aperture S3arranged at the lower edge portion of the sub-pixel p1corresponding to R (red) shown inFIG. 8has a light emission failure. Since the aperture S3does not emit light in this case, a distance between apertures which normally emit light will be a distance D between the aperture S2adjacent to the aperture S3having the light emission failure in the upward direction and the aperture S1of the sub-pixel p1in the main pixel P-2adjacent in the downward direction. In this case, the case in which the light emission failure occurs at the aperture S3of the sub-pixel p1corresponding to R (red) is cited as an example, however, it is also the same in cases in which the failure occurs at apertures S3of the sub-pixels p2, p3corresponding to G (green) and B (blue).

Present Embodiment

FIG. 9is a plan view explaining a specific example of apertures in the embodiment. In the drawing, apertures of two main pixels P-1, P-2which are vertically adjacent are shown. Since the apertures of two main pixels P-1, P-2are the same, a layout of the apertures will be explained by using the main pixel P-1here.

In the main pixel P-1, three sub-pixels p1, p2and p3are provided. Each of sub-pixels p1, p2and p3emits light corresponding to one color respectively. For example, the sub-pixel p1emits light corresponding to R (red), the sub-pixel p2emits light corresponding to G (green) and the sub-pixel p3emits light corresponding to B (blue).

Respective sub-pixels p1, p2and p3are laid out so that three apertures S1, S2and S3are aligned in one direction (vertical direction in the drawing) according to corresponding colors. The aperture sizes of respective apertures S1, S2and S3are defined by the aperture defining portion K (for example, an insulating film for defining apertures or a shielding film). In the embodiment, the apertures are provided so that the aperture size of the aperture S2other than apertures at both edge portions is larger than the aperture size of the apertures S1, S3at both edge portions in the three apertures S1, S2and S3.

The three apertures S1, S2and S3provided at respective sub-pixels p1, p2and p3emit light at the same time so as to correspond to respective colors. That is, when light of R (red) in the main pixel P-1is emitted, light is emitted from three apertures S1to S3of the sub-pixel p1corresponding to R (red) at the same time. Similarly, when light of G (green) in the main pixel P-1is emitted, light is emitted from three apertures S1to S3of the sub-pixel p2corresponding to G (green) at the same time. Also similarly, when light of B (blue) in the main pixel P-1is emitted, light is emitted from three apertures S1to S3of the sub-pixel p3corresponding to B (blue) at the same time.

Here, a case in which a light emission failure occurs at any one of three apertures S1, S2and S3in each of the sub-pixels p1, p2and p3will be explained. The light emission failure occurs due to a failure of a transistor corresponding to each of apertures S1, S2and S3, a failure between electrodes in the organic EL light emitting layer or the like.

For example, assume that the aperture S3arranged at the lower edge portion of the sub-pixel p1corresponding to R (red) shown inFIG. 9has a light emission failure. Since the aperture S3does not emit light in this case, a distance between apertures which normally emit light will be a distance D′ between the aperture S2adjacent to the aperture S3having the light emission failure in the upward direction and the aperture S1of the sub-pixel p1in the main pixel P-2adjacent in the downward direction. In this case, the case in which the light emission failure has occurred in the aperture S3of the sub-pixel p1corresponding to R (red) is cited as an example, however, it is also the same in cases in which the failure occurs at apertures S3of the sub-pixels p2and p3corresponding to G (green) and B (blue).

When comparing the embodiment with the comparative example, in the case where the light emission failure occurs at the same aperture S3of the sub-pixel p1corresponding to R (red), the distance of apertures normally emit light is D in the comparative example, whereas it is D′ in the embodiment. The distance D′ in the embodiment is shorter than the distance D in the comparative example. This is because the aperture sizes of the apertures S1, S2and S3included in respective sub-pixels p1, p2and p3are not equal and the aperture size of the aperture S2other than apertures at edge portions is larger than those of the apertures S1, S3at edge portions. Accordingly, in the embodiment, a non-light emitting region in the case where the light emission failure occurs at the aperture S3, namely, the distance D′ will be shorter than the distance D in the comparative example, as a result, it is hardly visible as a non-light emitting region.

Next, specific examples of apertures in the display device according to the embodiment will be explained.

Detailed Specific Example of the Embodiment

FIG. 10is a plan view explaining a detailed specific example (No. 1) of apertures in the display device according to the embodiment. In the drawing, apertures in two main pixels P-1, P-2adjacent in the vertical direction are shown. Concerning the layout of apertures shown inFIG. 10, three apertures S1, S2and S3are aligned in one direction (vertical direction in the drawing) in each of sub-pixels p1, p2and p3respectively formed in the main pixels P-1, P-2in the same manner as the layout of apertures shown inFIG. 9. The sizes of respective apertures S1, S2and S3are defined by the aperture defining portion K.

Since the same layout of apertures as the specific example shown inFIG. 9is applied in the detailed specific example shown inFIG. 10, detailed explanation of the main pixels P-1, P-2, the sub-pixels p1, p2and p3and the apertures S1, S2and S3is omitted. Therefore, the size configuration about the respective apertures S1, S2and S3as well as distances therebetween will be explained below in detail. Also, the layout of apertures is the same in respective sub-pixel p1, p2and p3, therefore, explanation will be made by using the sub-pixel p1.

As sizes used in explanation of the example shown inFIG. 10, lengths along the vertical direction in the drawing (direction of alignment of apertures S1to S3) are used. As the lengths along this direction, an aperture length of the aperture S1is denoted as L1, an aperture length of the aperture S2is denoted as L2and an aperture length of the aperture S3is denoted as L3. A distance between the aperture S1and the aperture S2as well as a distance between the aperture S2and the aperture S3are denoted as “a”. Additionally, a distance between the aperture S3and the aperture S1of the sub-pixel in the main pixel P-2adjacent in the downward direction is denoted as “b”. A length of the main pixel P-1is denoted as L.

In the example shown inFIG. 10, the aperture size L1of the aperture S1arranged at the upper edge portion of the sub-pixel p1is equal to the aperture size L3of the aperture S3arranged at the lower edge portion.
L1=L3

The aperture size L2of the aperture S2arranged at the center of the sub-pixel p1is larger than the aperture sizes L1, L3of the apertures S1, S3at the edge portions.
L2>L1,L2>L3

The distance “a” between the aperture S1and the aperture S2and the distance “a” between the aperture S2and the aperture S3in the sub-pixel p1are smaller than the distance “b” between the aperture S3at the lower edge portion of the sub-pixel p1in the main pixel P-1and the aperture S1at the upper edge portion of the sub-pixel p1in the main pixel P-2which is adjacent to the main pixel P-1in the vertical direction.
a<b

Moreover, a sum of the aperture size L3of the aperture S3, the distance “a” above L3and the distance “b” below L3is equal to a sum of the aperture size L2of the aperture S2, the distance “a” above L2and the distance “a” below L2.
L3+a+b=L2+2a

Furthermore, aperture lengths of the three apertures S1, S2and S3in the sub-pixel p1along the horizontal direction in the drawing are equal. The length L of the main pixel P-1is equal to L1+L2+L3+2a+b.

According to the above relationship, when the light emission failure occurs in any of the three apertures S1, S2and S3, distances between adjacent apertures which normally emit light can be approximately equal in the embodiment.

For example, when the light emission failure occurs at the aperture S3arranged at the lower edge portion of the sub-pixel p1, a length of a region in which light of color corresponding to the sub-pixel p1(red) is reduced will be the length obtained by adding the aperture size L3of the aperture S3to the distances “a”, “b” which are above and below the aperture S3. That is, when the light emission failure occurs at the aperture S3, the distance from the lower edge of the aperture S2adjacent in the upward direction to the upper edge of the aperture S1positioned at the upper edge portion of the sub-pixel p1in the main pixel P-2adjacent in the downward direction will be the region in which light emission failure occurs. The light emission failure region is expressed as L3+a+b.

When the light emission failure occurs at the aperture S2arranged at the center of the sub-pixel p1, a length of a region in which light of color corresponding to the sub-pixel p1(red) is reduced will be the length obtained by adding the aperture size L2of the aperture S2to respective distances “a” which are above and below the aperture S2. That is, when the light emission failure occurs at the aperture S2, the distance from the lower edge of the aperture S1adjacent in the upward direction to the upper edge of the aperture S3adjacent in the downward direction will be the region in which light emission failure occurs. The light emission failure region is expressed as L2+2a.

In the embodiment, the light emission failure region L3+a+b in the case where the aperture S3has the light emission failure is equal to the light emission region L2+2a in the case in which the aperture S2has the light emission failure.

According to this, when the light emission failure occurs at any of the three apertures S1, S2and S3provided in the sub-pixel p1, distances between apertures which normally emit light adjacent above and below the aperture having the failure can be equal. That is, when the light emission failure occurs at any aperture, the light emission failure regions will be equal, therefore, the difference in visibility as a non-light emitting region is not generated according to the position of the aperture.

The example of L3+a+b=L2+2a has been explained as the above, however, L3+a+b≦L2+2a is also preferable. This relational expression includes L3+a+b<L2+2a, however, in that case, even when the light emission failure occurs at the aperture S2arranged at the center of the sub-pixel p1, the difference in visibility as the non-light emitting region can be interpolated by increasing light emitting luminance of the apertures S1, S3which normally emit light.

Detailed Specific Example of the Embodiment

FIG. 11is a plan view explaining a detailed specific example (No. 2) of apertures in the display device according to the embodiment. In the drawing, apertures in two main pixels P-1, P-2adjacent in the vertical direction are shown. Concerning the layout of apertures shown inFIG. 11, four apertures S1, S2, S3and S4are aligned in one direction (vertical direction in the drawing) in each of sub-pixels p1, p2and p3respectively formed in the main pixels P-1, P-2. The sizes of respective apertures S1to S4are defined by the aperture defining portion K.

In the following description, the size configuration about the respective apertures S1, S2, S3and S4as well as distances therebetween will be explained in detail. Also, the layout of apertures is the same in respective sub-pixel p1, p2and p3, therefore, explanation will be made by using the sub-pixel p1.

As sizes used in explanation of the example shown inFIG. 11, lengths along the vertical direction in the drawing (direction of alignment of apertures S1to S4) are used. As the lengths along this direction, an aperture length of the aperture S1is denoted as L1, an aperture length of the aperture S2is denoted as L2, an aperture length of the aperture S3is denoted as L3and an aperture length of the aperture S4is denoted as L4. A distance between the aperture S1and the aperture S2, a distance between the aperture S2and the aperture S3and a distance between the aperture S3and the aperture S4are denoted as “a”. Additionally, a distance between the aperture S4and the aperture S1of the sub-pixel in the main pixel P-2adjacent in the downward direction is denoted as “b”. A length of the main pixel P-1is denoted as L.

In the example shown inFIG. 11, the aperture size L1of the aperture S1arranged at the upper edge portion of the sub-pixel p1is equal to the aperture size L4of the aperture S4arranged at the lower edge portion.
L1=L4

The aperture size L2of the aperture S2and the aperture size L3of the aperture S3arranged at positions other than both edge portions in the sub pixel p1are equal.
L2=L3

The aperture sizes L2, L3of the apertures S2, S3arranged at positions other than both edge portions of the sub pixel p1are larger than the aperture sizes L1, L4of the apertures S1, S4at edge portions.
L2=L3>L1=L4

The distance “a” between respective apertures S1to S4in the sub-pixel p1are smaller than the distance “b” between the aperture S4at the lower edge portion of the sub-pixel p1in the main pixel P-1and the aperture S1at the upper edge portion of the sub-pixel p1in the main pixel P-2which is adjacent to the main pixel P-1in the vertical direction.
a<b

Moreover, a sum of the aperture size L4of the aperture S4, the distance “a” above L4and the distance “b” below L4is equal to a sum of the aperture size L2or the aperture size L3of the aperture S2or the aperture S3, the distance “a” above L2or L3and the distance “a” below L2or L3.
L4+a+b=L2+2a
L4+a+b=L3+2a

Furthermore, aperture lengths of the four apertures S1, S2, S3and S4in the sub-pixel p1along the horizontal direction in the drawing are equal. The length L of the main pixel P-1is equal to L1+L2+L3+L4+3a+b.

According to the above relationship, when the light emission failure occurs in any of the four apertures S1, S2, S3and S4, distances between adjacent apertures which normally emit light can be approximately equal in the embodiment.

For example, when the light emission failure occurs at the aperture S4arranged at the lower edge portion of the sub-pixel p1, a length of a region in which light of color corresponding to the sub-pixel p1(red) is reduced will be the length obtained by adding the aperture size L4of the aperture S4to the distances “a”, “b” which are above and below the aperture S4. That is, when the light emission failure occurs at the aperture S4, the distance from the lower edge of the aperture S3adjacent in the upward direction to the upper edge of the aperture S1positioned at the upper edge portion of the sub-pixel p1in the main pixel P-2adjacent in the downward direction will be the region in which light emission failure occurs. The light emission failure region is expressed as L4+a+b.

When the light emission failure occurs at the aperture S2or the aperture S3arranged at the center of the sub-pixel p1, a length of a region in which light of color corresponding to the sub-pixel p1(red) is reduced will be the length obtained by adding the aperture size L2of the aperture S2or the aperture size L3of the aperture S3to respective distances “a” which are above and below the aperture S2or the aperture S3. That is, when the light emission failure occurs at the aperture S2, the distance from the lower edge of the aperture S1adjacent in the upward direction to the upper edge of the aperture S3adjacent in the downward direction will be the region in which light emission failure occurs. The light emission failure region is expressed as L2+2a. Also, when the light emission failure occurs at the aperture S3, the distance from the lower edge of the aperture S2adjacent in the upward direction to the upper edge of the aperture S4adjacent in the downward direction will be the region in which light emission failure occurs. The light emission failure region is expressed as L3+2a.

In the embodiment, the light emission failure region L4+a+b in the case where the aperture S4has the light emission failure is equal to the light emission failure region L2+2a or L3+2a in the case where the aperture S2or the aperture S3has the light emission failure.

In the case where four apertures S1to S4are provided at the sub-pixel p1as described above, the same effects as the case of three apertures can be obtained. That is, when the light emission failure occurs at any of the four apertures S1, S2, S3and S4, distances between adjacent apertures which normally emit light can be approximately equal. Therefore, when the light emission failure occurs at any aperture, the light emission failure regions will be equal, therefore, the difference in visibility as a non-light emitting region is not generated according to the position of the aperture.

The examples of L4+a+b=L2+2a, L4+a+b=L3+2a have been explained as the above, however, L4+a+b≦L2+2a, L4+a+b≦L3+2a are also preferable. This relational expressions include L4+a+b<L2+2a, L4+a+b<L3+2a, however, in the same manner as the above, even when the light emission failure occurs at the aperture S2or S3arranged at the center of the sub-pixel p1, the difference in visibility of the non-light emitting region can be interpolated by increasing light emitting luminance of the apertures which normally emit light.

In addition to the case of three apertures and the case of four apertures as described above, the same concept can be applied also to cases of five or more apertures, whereby the same effects can be obtained.

4. Application Example

The display device according to the embodiment described above can be applied to various electronic apparatuses by being provided in main casings thereof. As examples, the display device can be applied to various electronic apparatuses shown inFIG. 12toFIG. 16G. For example, the invention can be applied to display devices of electronic apparatuses in various fields in which a video signal inputted to the electronic apparatus or a video signal generated in the electronic apparatus is displayed as images or video, such as a digital camera, a notebook personal computer, portable terminal devices such as a cellular phone and a video camera.

As described above, the display device according to the embodiment is used as display devices for electronic apparatuses in various fields, thereby improving image quality of display images, therefore, there is an advantage that good quality images can be displayed in various electronic apparatuses.

The display device according to the embodiment also includes a module-shaped device having a sealed structure. For example, a display module formed by a pixel array portion102being bonded to an opposite portion such as a transparent glass is appropriate. It is also preferable that color filters, a protection film, a shielding film and so on are provided on the transparent opposite portion. The display module may be provided with a circuit portion or a FPC (flexible print circuit) for inputting and outputting a signal and the like from the outside to the pixel array portion.

Specific examples of electronic apparatuses to which the display device according to the embodiment is applied will be explained below.

FIG. 12is a perspective view showing an appearance of a television set to which the embodiment is applied. The television set according to the application example includes a video display screen portion107having a front panel108, a filter glass109and the like, which is manufactured by using the display device according to the embodiment as the video display screen portion107.

FIG. 13AandFIG. 13Bare perspective views showing an appearance of a digital camera to which the embodiment is applied.FIG. 13Ais a perspective view seen from the front andFIG. 13Bis a perspective view seen from the back. The digital camera according to the embodiment includes a light emitting portion111for flash, a display portion112, a menu switch113, a shutter button114and so on, which is manufactured by using the display device according to the embodiment as the display portion112.

FIG. 14is a perspective view showing an appearance of a notebook personal computer to which the embodiment is applied. The notebook personal computer according to the application example includes a body121, a keyboard122operated when inputting characters and the like and a display portion123displaying images and so on, which is manufactured by using the display device according to the embodiment as the display portion123.

FIG. 15is a perspective view showing an appearance of a video camera to which the embodiment is applied. The video camera according to the application example includes a body131, a lens132for imaging objects at a side surface facing the front and a start/stop switch133used at the time of imaging and a display portion134and the like, which is manufactured by using the display device according to the embodiment as the display portion134.

FIG. 16AtoFIG. 16Gare exterior views showing a portable terminal device, for example, a cellular phone device to which the embodiment is applied.FIG. 16Ais a front view in an opened state,FIG. 16Bis a side view thereof,FIG. 16Cis a front view in an closed state,FIG. 16Dis a left-side view,FIG. 16Eis a right-side view,FIG. 16Fis an upper surface view andFIG. 16Gis a lower surface view. The cellular phone device according to the embodiment includes an upper casing141, a lower casing142, a connecting portion (a hinge portion in this case)143, a display144, a sub-display145, a picture light146, a camera147and so on, which is manufactured by using the display device according to the embodiment as the display144or the sub-display145.

The present application contains subject matter related to that disclosed in Japanese Priority Patent Application JP 2009-096609 filed in the Japan Patent Office on Apr. 13, 2009, the entire contents of which is hereby incorporated by reference.