JP2013105148A - Display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display device capable of suppressing reduction of display quality without causing enlargement and thickening of the device.SOLUTION: A light emission part 40 is disposed on a side of one surface 11a of a substrate 11 for each of a plurality of pixel portions. A plurality of kinds of wiring is disposed, which is arranged in a matrix state on the substrate according to a position of the plurality of pixel portions, and where power usage related to light emission of the light emission part is transmitted. At least a part of at least one kind of the wiring 33 among the plurality of kinds of wiring is disposed to face a side of the other surface 11b of the substrate.

Description

  The present invention relates to a display device.

  An organic EL display having an organic EL (electroluminescence) element corresponding to a pixel has high brightness and self-emission, can be driven by a DC low voltage, has high responsiveness, a solid organic film Therefore, it is expected to be a display device that will replace the liquid crystal display in the future because it is excellent in display performance and can be reduced in thickness, weight, and power consumption.

  In the display devices described above, display using a dot matrix in which a plurality of pixel portions are arranged in a grid pattern is the mainstream. In the dot matrix display, if individual wiring is performed for each of the plurality of pixel portions, the peripheral edge of the substrate is filled with the wiring and becomes unrealistic. Therefore, the scanning lines and the signal lines are arranged in a two-dimensional arrangement in the vertical and horizontal directions. A matrix wiring system is employed in which the electrodes of the pixel portion are controlled at the intersections of the wirings (see, for example, Patent Document 1).

  In such a configuration, when the scanning line is driven and a switching element such as a TFT is turned on, the potential (power) of the signal line at that time is held in the holding capacitor, and the driving transistor is driven according to the state of the holding capacitor. ON / OFF is determined. Then, a current flows from the power supply line to the pixel electrode through the channel of the driving transistor, and a current flows to the common electrode through the light emitting unit, whereby the light emitting unit emits light according to the amount of current.

JP 2001-118301 A

However, the following problems exist in the conventional technology as described above.
For example, although a large number of pixel portions are arranged along the extending direction of the power supply line, a voltage drop occurs due to the influence of the wiring resistance of the power supply line, so that the light emission of the organic EL element occurs in the pixel portion far from the power supply source. There is a possibility that a sufficient current value for causing light to be emitted by the portion cannot be obtained.
In addition, when the wiring resistance of the scanning line is large, there is a possibility that a signal transmission delay may occur, and there is a possibility that the display quality is deteriorated similarly to the case of the power line.
Therefore, in order to solve such a problem, a method of reducing the wiring resistance by increasing the wiring such as the power supply line or the scanning line or by increasing the width can be considered. The thickness is limited, and when this method is adopted, the apparatus may be increased in size and thickness.

  The present invention has been made in consideration of the above points, and an object of the present invention is to provide a display device that can prevent deterioration in display quality without causing an increase in size and thickness of the device.

  According to the first aspect of the present invention, a light emitting unit is provided for each of the plurality of pixel units on one surface side of the substrate, and the substrate is arranged in a matrix on the substrate corresponding to the positions of the plurality of pixel units. A plurality of types of wirings for transmitting the power related to light emission of the light emitting unit are provided, and at least a part of at least one type of the plurality of types of wirings is provided facing the other surface side of the substrate. A display device is provided.

Therefore, in the configuration of the display device of this aspect, at least a part of at least one kind of wiring is provided facing the other surface side of the substrate, so that the cross-sectional area of the wiring can be increased to reduce the wiring resistance. it can.
The utility according to the present invention includes power for causing the light emitting unit to emit light, a driving signal as timing information related to light emission of the light emitting unit, and the like.

  In the above configuration, the at least one type of wiring includes a first wiring portion provided on one surface side of the substrate, a second wiring portion provided facing the other surface side of the substrate, and the substrate. A configuration including a third wiring portion that is provided penetrating in the thickness direction and that connects the first wiring portion and the second wiring portion can be suitably employed.

  Therefore, in the configuration of the display device of the present invention, the cross-sectional area of at least one type of wiring is the total value of the cross-sectional areas of the first wiring portion, the second wiring portion, and the third wiring portion, and the wiring resistance of the wiring is reduced. Can do.

In addition, as the second wiring portion in the above configuration, a configuration provided so as to protrude from the other surface of the substrate can be suitably employed.
Therefore, in the configuration of the display device of the present invention, the second wiring portion is formed on the other surface of the substrate in which the restriction on the wiring formation is relaxed, thereby increasing the cross-sectional area of at least one kind of wiring. The wiring resistance can be further reduced.
As the second wiring part in this configuration, it is possible to suitably employ a structure formed with a larger area than the first wiring part.

In addition, as the second wiring portion in the above configuration, a configuration in which the second wiring portion is provided substantially flush with the other surface of the substrate in a recess formed on the other surface of the substrate can be suitably employed.
Accordingly, in the configuration of the display device of the present invention, since the second wiring portion does not protrude from the other surface of the substrate, it is possible to reduce the thickness of the device while increasing the cross-sectional area of at least one kind of wiring.

  According to the present invention, it is possible to provide a display device that can prevent display quality from being deteriorated by reducing the wiring resistance without increasing the size and thickness of the device.

The circuit block diagram of the display apparatus 10 which concerns on 1st Embodiment. 2 is a diagram showing a configuration example of one pixel cell in the active drive display device 10. FIG. The figure which shows the principal part cross-section structure in FIG. The figure for demonstrating the means to form a through-hole in a board | substrate. The figure which shows the example which provided the bus-bar and wiring in the surface side of a board | substrate. The figure which shows the relationship between the distance between a bus-bar and wiring, and a capacity | capacitance. The figure which shows the principal part cross-section structure of the display apparatus 10 which concerns on 2nd Embodiment. FIG. 3 is a diagram showing a configuration example of one pixel cell in the display device 10. The figure which shows the principal part cross-section structure of the display apparatus 10 which concerns on 3rd Embodiment. FIG. 3 is a cross-sectional view of a main part of the display device 10. The figure which shows the principal part cross-section structure of the display apparatus 10 which concerns on other embodiment. The figure which shows the principal part cross-section structure of the display apparatus 10 from which light emission directions differ. The figure which shows the principal part cross-section structure of the display apparatus 10 from which light emission directions differ. The figure which shows the principal part cross-section structure of the display apparatus 10 from which light emission directions differ.

Embodiments of a display device according to the present invention will be described below with reference to FIGS.
Here, the display device will be described using an example of an organic EL display using an organic electroluminescence element (hereinafter referred to as an organic EL (Electroluminescence) element).

(First embodiment)
1 is a circuit configuration diagram of a display device 10 according to the present embodiment, FIG. 2 is a diagram illustrating a configuration example of one pixel cell in the active drive display device 10, and FIG. 3 is a diagram illustrating a cross-sectional configuration of a main part in FIG. It is.

  As shown in FIG. 1, the display device 10 includes a plurality of scanning lines (wirings) 31 and a plurality of signal lines (wirings) 32 extending in a direction intersecting the scanning lines 31 on a transparent substrate. A plurality of common power supply lines (wirings) 33 extending in parallel to the signal lines 32 are respectively wired, and a plurality of pixel portions 1 are arranged in a matrix at each intersection of the scanning lines 31 and the signal lines 32. It is configured.

  For the signal line 32, a data side drive circuit 2 including a shift register, a level shifter, a video line, an analog switch, and the like is provided. On the other hand, a scanning side driving circuit 3 including a shift register, a level shifter, and the like is provided for the scanning line 31. Further, a switching TFT (thin film transistor) 42 to which a scanning signal as utility is supplied to the gate electrode via the scanning line 31 and a signal line 32 via the switching thin film transistor 42 are supplied to each pixel portion 1. A holding capacitor cap that holds an image signal as a power to be used, a driving TFT (thin film transistor) 43 to which an image signal held by the holding capacitor cap is supplied to a gate electrode, and a common power source via the driving thin film transistor 43 A pixel electrode 41 into which a driving current as utility power flows from the common power supply line 33 when electrically connected to the line 33 and a light emitting unit 40 sandwiched between the pixel electrode 41 and the common electrode 54 are provided. Yes. An element constituted by the pixel electrode 41, the common electrode 54, and the light emitting unit 40 is an organic EL device (organic EL element) 100.

  Under such a configuration, when the scanning line 31 is driven and the switching thin film transistor 42 is turned on, the potential of the signal line 32 at that time is held in the holding capacitor cap, and according to the state of the holding capacitor cap. The on / off state of the driving thin film transistor 43 is determined. Then, a current flows from the common power supply line 33 to the pixel electrode 41 through the channel of the driving thin film transistor 43, and further, a current flows to the common electrode 54 through the light emitting unit 40, so that the light emitting unit 40 has an amount of current flowing therethrough. Accordingly, the light is emitted.

FIG. 2A is a conceptual diagram showing a circuit of one pixel unit 1, and FIG. 2B is a layout diagram of the circuit of FIG.
The pixel unit 1 has an arrangement in which four sides of a pixel electrode 41 having a substantially rectangular shape in plan view are surrounded by a signal line 32, a common power supply line 33, a scanning line 31, and scanning lines for other pixel electrodes (not shown). .

FIG. 3 is a schematic cross-sectional view of the display device 10.
As shown in this figure, the organic EL device 100 is provided on the upper surface (one surface) 11a side of the substrate 11, and the light emitted by the organic EL device 100 is emitted from the back surface (other surface) 10b side of the substrate 11. It is configured to take out. As the substrate 11, since it is necessary to transmit light emitted from the organic EL device 100, a transparent synthetic resin material, ultrathin glass having a thickness of about 100 μm, or the like is used.

  Similarly, a transparent conductive material is used as the pixel electrode 41 because it is necessary to transmit light emitted from the organic EL device 100. Specifically, metal oxides such as ITO (Indium Tin Oxide) can be used in consideration of a hole injection effect with a work function described later of 5 eV or more.

  As the common electrode 54, for example, an electrode having a laminated structure in which lithium fluoride (LiF) is formed to a thickness of about 5 nm and aluminum (Al) is formed to a thickness of about 300 nm can be used. If the transparent material is used for the common electrode 54, the emitted light can be emitted from the cathode side. As the transparent material, for example, ITO, Pt, Ir, Ni, or Pd can be used.

  The organic EL device 100 includes the pixel electrode 41 as an anode, the hole injection / transport layer 12, the host layer 13, the light emitting layer 14, and the common electrode 54 as a cathode. The organic EL device 100 is not limited to this configuration. For example, a hole injection / transport layer, a host layer, a light emitting layer, a hole block layer, and an electron transport layer are stacked between the pixel electrode 41 and the common electrode 54. A configuration or the like may be employed.

  As a material for forming the hole injection / transport layer 12, for example, a dispersion liquid of 3,4-polyethylenediosithiophene-polystyrene sulfonic acid (PEDOT-PSS) can be used. Specifically, a dispersion obtained by dispersing 3,4-polyethylenedithiothiophene in polystyrene sulfonic acid as a dispersion and further dispersing it in water can be suitably used. In addition, conventionally known hole injecting / transporting materials can be used. The hole injection / transport layer 12 has a function of transporting holes therein, and also has a function of injecting and transporting holes to the light emitting layer 14 side.

  The host layer 13 is formed including a host material, and for example, CBP (4,4′-bis (9-dicarbazolyl) -2,2′-biphenyl) can be used as the host material. . In addition, BAlq (Bis- (2-methyl-8-quinolinolate) -4- (phenylphenolate) aluminum), mCP (N, N-dicarbazolyl-3,5-benzene: CBP derivative), CDBP (4, 4'-bis (9-carbazolyl) -2,2'-dimethyl-biphenyl), DCB (N, N'-Dicarbazolyl-1,4-dimethene-benzene), P06 (2,7-bis (diphenylphosphine oxide)- 9,9-dimethylfluorene), SimCP (3,5-bis (9-carbazolyl) tetraphenylsilane), UGH3 (W-bis (triphenylsilyl) benzene) can be used.

  As the light emitting layer 14, a known light emitting material capable of emitting fluorescence or phosphorescence can be used. Specific examples of the material for forming the light emitting layer 14 include (poly) fluorene derivative (PF), (poly) paraphenylene vinylene derivative (PPV), polyphenylene derivative (PP), polyparaphenylene derivative (PPP), and polyvinylcarbazole. Polysilanes such as (PVK), polythiophene derivatives, and polymethylphenylsilane (PMPS) are preferably used. In addition, these polymer materials include polymer materials such as perylene dyes, coumarin dyes, rhodamine dyes, rubrene, perylene, 9,10-diphenylanthracene, tetraphenylbutadiene, Nile red, coumarin 6, and quinacridone. It can also be used by doping a low molecular weight material such as.

  In the present embodiment, a part of the common power supply line 33 that transmits a driving current to the pixel electrode 41 (organic EL device 100) via the driving TFT is provided on the back surface 11b side in addition to the front surface 11a side of the substrate 11. ing. That is, as shown in FIG. 3, the common power line 33 includes a first wiring portion 33 a provided on the front surface 11 a side of the substrate 11, a second wiring portion 33 b provided facing the back surface 11 b side, and the substrate 11. It is comprised from the 3rd wiring part 33c provided by penetrating.

  The second wiring portion 33b protrudes from the back surface 11b and is wider than the first wiring portion 33a so as to have a larger area than the first wiring portion 33a as shown in FIG. ing. The size of the third wiring portion 33c is set according to the strength of the substrate 11 because a through hole is formed in the substrate 11, and in this embodiment, a circular cross section having substantially the same diameter as the width of the first wiring portion 33a. Thus, a plurality of gaps are formed in the length direction of the first wiring portion 33a.

  When the display device 10 having the above configuration is manufactured, first, a through hole for forming the third wiring portion 33 c of the common power supply line 33 is formed in the substrate 11. Specifically, as shown in FIG. 4A, the first step of moving the punching device PR with respect to the substrate 11 to form the through hole 11c at the position where the third wiring portion 33c is to be formed; By repeating the second step of moving the substrate 11 by a predetermined distance along the extending direction of the common power supply line 33, a plurality of through holes 11c are formed with gaps along the extending direction of the common power supply line 33. The In the second step, the punching device PR may be moved instead of moving the substrate 11. When the substrate 11 is an extremely thin glass and an insulating protective film is pasted, the substrate can be removed without peeling off the protective film if the total thickness is allowed even if the thickness of the protective film is added. Eleven insulating layers may be left. Further, the means for forming the through hole 11c is not limited to punching, and may be cutting or drilling using laser light.

  When the through hole 11c is formed in the substrate 11, the third wiring part 33c is formed in the through hole 11c. As a method for forming the third wiring portion 33c, a material for the surface of the substrate is applied after applying a material for forming the third wiring portion 33c containing metal fine particles such as chromium on the substrate 11 by using a dispensing method or a spin coating method. A method of removing the film, a method of applying a liquid material in which the forming material of the third wiring part 33c is dissolved or dispersed in a solvent into the through hole 11c using an ink jet method, a method of forming by vapor deposition or the like are employed. When vapor deposition or the like is used, the third wiring portion 33c is formed on the wall surface of the through hole 11c. Therefore, the formation material of the third wiring portion 33c is filled into the through hole 11c by other methods. The method is suitable from the viewpoint of reducing the wiring resistance.

  When the third wiring portion 33 c is formed in the through hole 11 c of the substrate 11, the second wiring portion 33 b is then formed on the back surface 11 b of the substrate 11. As a method of forming the second wiring portion 33b, a method of applying and patterning the second wiring portion forming material by the above-described ink jet method, or a method of applying the second wiring portion forming material by using the above-described dispensing method and spin coating method. Then, after the metal film is formed so as to cover the entire back surface 11b of the substrate 11, a method of patterning the metal film by a photolithography method or the like can be employed.

  When the second and third wiring portions 33b and 33c are formed on the substrate 11, other wiring (pixel electrode 41 and signal line 32) including the first wiring portion 33a is formed on the surface 11a side. As a method of forming the first wiring part 33a, the same method as that of the third wiring part 33c can be adopted. When other wiring including the first wiring part 33a is formed on the surface 11a side, the scanning line 31, the insulating film 35, the switching thin film transistor 42, the driving thin film transistor 43, the light emitting part 40, the common electrode 54, and the like are known. It forms using.

  In the display device 10 having the above-described configuration, when the switching thin film transistor 42 and the driving thin film transistor 43 are on, current flows from the common power supply line 33 to the pixel electrode 41 via the driving thin film transistor 43. The light emitting unit 40 emits light, but the common power line 33 is exposed not only at the first wiring unit 33a but also at the back surface 11b side of the substrate 11, and the first and second wiring units 33a and 33b. Therefore, at least the area where the second and third wiring portions 33b and 33c are arranged becomes larger in cross section, and the wiring resistance can be reduced.

(Example)
Using the conditions such as wiring described in Non-Patent Document 1 (Y. Nakajima et al., JOURNAL OF THE SOCIETY FOR INFORMATION DISPLAY Volume: Issue 19: 1 Page: 94-99 issued; JAN 2011) The case of driving a display device of Super Hi-Vision (SHV: Non-Patent Document 2 (SHV: ITU-R BT.1706, SMPTE 2036-1)) as a pixel display will be verified.

When the resistivity of the common power supply line 33 is ρ, the thickness is d, the wiring length is L, and the wiring width is W, the wiring resistance Rs of the common power supply line 33 is expressed by the following equation.
Rs = ρ × (1 / d) × (L / W) (1)
When one width of the pixel portion 1 is a and the number of pixels in the direction in which the RGB pixel portions 1 are arranged is m, the wiring length L is expressed by the following equation.
L = 3 × a × m (2)
From equations (1) and (2), the wiring resistance Rs is expressed by the following equation.
Rs = (3 × ρ × m × a) / (d × W) (3)

The following values are used from the parameters described in Document 1.
ρ = 5.7 × 10 ⁻⁸ (Ωm)
d = 50 × 10 ⁻⁹ (m)
W = 15 × 10 ⁻⁶ (m)
3 × a = 254 × 10 ⁻⁶ (m)
(A≈84.7 μm; 100 ppi)
m = 7680 (pieces) (assuming SHV)

Further, assuming that the maximum value of the current flowing through the organic EL device 100 is Ie, the maximum value Is of the current flowing through the common power supply line 33 is expressed by the following equation.
Is = Ie × 3 × m (4)
From the equations (1) to (4), the maximum value Vd of the voltage drop generated in the common power supply line 33 is expressed by the following equation.
Vd = Is × Rs
= 9 × a × m ² × Ie × ρ / (d × W) (5)

When Ie = 1 × 10 ⁻⁶ (A), a voltage drop value of Vd≈3400 (V) is obtained from Equation (5).

It is also conceivable to reduce the voltage drop by using only the first wiring part 33a without forming the second and third wiring parts 33b and 33c and devising the wiring material, wiring thickness, and wiring width.
For example, the wiring material is Cu, the wiring thickness is 5 times, and the wiring width is 2 times.
ρ = 1.7 × 10 ⁻⁸ (Ωm)
d = 250 × 10 ⁻⁹ (m)
W = 30 × 10 ⁻⁶ (m)
3 × a = 254 × 10 ⁻⁶ (m)
(A≈84.7 μm; 100 ppi)
m = 7680 (pieces) (assuming SHV)

In this case, if Ie = 1 × 10 ⁻⁶ (A), a voltage drop value of Vd≈100 (V) can be obtained from the equation (5), but this is not sufficient.

Therefore, when the second and third wiring portions 33b and 33c described above are used, in particular, the third wiring portion 33c is formed on the back surface 11b side with much less restrictions than the front surface 11a of the substrate 11. The width can be increased. Further, by using the third wiring portion 33b, the wiring thickness can be increased according to the thickness of the substrate 11.
For example, the wiring material is Cu and the wiring thickness is 50 times and the wiring width is doubled with respect to the condition that Vd≈100 (V) is obtained.
ρ = 1.7 × 10 ⁻⁸ (Ωm)
d = 12.5 × 10 ⁻⁶ (m)
W = 60 × 10 ⁻⁶ (m)
3 × a = 254 × 10 ⁻⁶ (m)
(A≈84.7 μm; 100 ppi)
m = 7680 (pieces) (assuming SHV)

In this case, assuming that Ie = 1 × 10 ⁻⁶ (A), the voltage drop is greatly suppressed as Vd≈1.00 (V) from the equation (5).

On the other hand, in order to suppress the voltage drop, as shown in FIG. 5, it is also possible to form the bus line ML on the surface 11a side of the substrate 11 and form the first wiring part 33a after forming the insulating film S. However, in this case, the parasitic capacitance generated between the bus line ML and the first wiring part 33a may adversely affect the moving image display.
For example, the wiring resistance Rs is obtained from the following parameters based on the wiring conditions of Non-Patent Document 1 described above.
ρ = 5.7 × 10 ⁻⁸ (Ωm) (Mo resistivity)
d = 50 × 10 ⁻⁹ (m)
W = 37 × 10 ⁻⁶ (m)
L = 106 × 10 ⁻⁶ (m) (wiring length of one pixel portion 1)
The wiring resistance Rs obtained from these parameters is 3.3Ω.

In this case, the parasitic capacitance generated between the bus ML and the first wiring portion 33a and the thickness of the insulating film S, which is the distance between the bus ML and the first wiring portion 33a, are shown in FIG. It becomes. From this relationship, for example, when the insulating film S is formed of SiO ₂ , the parasitic capacitance is 140 (fF) when the relative dielectric constant εr = 3.9 and the thickness is 1 μm (1000 nm).
On the other hand, when the third wiring portion 33c is formed on the back surface 11b side of the substrate 11, if the substrate 11 is a PEN substrate and the relative dielectric constant εr = 3.0 and the thickness is 100 μm, one pixel portion 1 The parasitic capacitance is 4.2 (fF), which is about 1/30 that of a mother ship formed on the surface.

  As described above, in the present embodiment, even when a large number of pixel portions 1 are arranged along the direction in which the common power supply line 33 extends, the first on the surface 11a side where the restrictions on the width and the thickness 1 are large. The wiring resistance can be reduced without increasing the area / thickness of the one wiring portion 33a, and it is possible to suppress problems caused by a voltage drop. In particular, in the present embodiment, since the third wiring portion 33c protrudes from the back surface 11b, the wiring resistance can be reduced more effectively.

  Further, in the present embodiment, when the bus bar is formed on the front surface side 11 a side of the substrate 11 for the purpose of suppressing the voltage drop by forming the third wiring portion 33 c facing the back surface 11 b side of the substrate 11. Compared to the above, it is possible to increase the distance between the third wiring portion 33c and the first wiring portion 33a as a bus, and as a result, the parasitic capacitance generated due to the suppression of the voltage drop using the bus It can be effectively reduced.

(Second Embodiment)
Next, a second embodiment of the display device 10 will be described with reference to FIGS. 4B, 7 and 8. FIG.
In these drawings, the same components as those of the first embodiment shown in FIGS. 1 to 6 are denoted by the same reference numerals, and the description thereof is omitted.
In the first embodiment, a part of the common power supply line 33 is formed on the back surface side 11b of the substrate 11. However, in the second embodiment, a part of the scanning line 31 is formed on the back surface side 11b of the substrate 11. The case will be described.

  As shown in FIG. 7, the scanning line 31 in the present embodiment is formed on the insulating film 35 that covers the pixel electrode 41 and the common power supply line 33 on the surface 11 a side of the substrate 11 and is connected to the switching thin film transistor 42. The first wiring part 31a, the second wiring part 31b provided facing the back surface 11b, and the third wiring part 31c provided through the substrate 11 are configured. The first wiring part 31a and the third wiring part 31c are connected by a contact hole CH.

The second wiring portion 31b is provided wider than the first wiring portion 31a so as to protrude from the back surface 11b and to have a larger area than the first wiring portion 31a as shown in FIG. The size of the third wiring portion 31c is set according to the strength of the substrate 11 because a through hole is formed in the substrate 11. In the present embodiment, the size of the third wiring portion 31c is substantially the same as the width of the first wiring portion 31a. It is formed in a linear shape extending in the extending direction of the first wiring portion 31 a at a position separated from the intersection with the common power supply line 33.
Other configurations are the same as those of the first embodiment.

  When the third wiring part 31c is formed on the substrate 11 in the display device 10 having the above configuration, as shown in FIG. 4B, the groove forming device SL such as a cutting device is moved with respect to the substrate 11. The through groove 11d is formed at a position where the third wiring portion 31c is to be formed. The through-groove 11d may also be formed by drilling using laser light, similar to the above-described through-hole 11c.

  For the substrate 11 on which the through groove 11d is formed, the third wiring part 31c is formed in the same process as the third wiring part 33c described above, and the first wiring part 31a, the second wiring part 31b, and the contact are formed. The holes CH and the like can also be formed by the same process as the first embodiment described above or a known method.

  Also in the display device 10 of the present embodiment, even when a large number of pixel portions 1 are arranged along the direction in which the scanning lines 31 extend, the first wiring on the surface 11a side where the restrictions on the width and the thickness 1 are large. Wiring resistance can be reduced without increasing the area and thickness of the portion 31a. For this reason, in the present embodiment, it is possible to suppress the delay of the moving image without increasing the size and thickness of the apparatus, and it is possible to prevent the display quality from being deteriorated.

(Third embodiment)
Next, a third embodiment of the display device 10 will be described with reference to FIGS.
In these drawings, the same components as those of the first embodiment shown in FIGS. 1 to 6 are denoted by the same reference numerals, and the description thereof is omitted.
In the first embodiment, the second wiring portion 33b of the common power supply line 33 is provided so as to protrude from the back surface 11b of the substrate 11. However, in the third embodiment, the common power line 33 is provided substantially flush with the back surface 11b of the substrate 11. The case where it will be described.

  As shown in FIG. 9 and FIG. 10 which is a cross-sectional view in the width direction of the first and second wiring portions 33a and 33b, the back surface 11b of the substrate 11 in this embodiment is planarly the same as the second wiring portion 33b. In the shape, a recess 11e whose depth is the thickness of the second wiring portion 33b is formed. A through hole 11c that penetrates to the surface 11a side of the substrate 11 is formed at the bottom of the recess 11e. A second wiring portion 33b is embedded in the recess 11e flush with the back surface 11b. The through hole 11c is provided with a third wiring portion 33b that connects the first wiring portion 33a and the second wiring portion 33b.

  In the present embodiment, in addition to obtaining the same operation and effect as the first embodiment, the second wiring portion 33b does not protrude from the back surface 11b of the substrate 11, so that the thickness of the device can be increased. It becomes possible to prevent.

  As described above, the preferred embodiments according to the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to the examples. Various shapes, combinations, and the like of the constituent members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

  For example, in the above-described embodiment, the configuration in which the common power supply line 33 and the scanning line 31 are provided facing the back surface 11b side of the substrate 11 has been described, but needless to say, the configuration can be applied to the signal line 32 as well. Also in this case, since the potential held in the storage capacitor becomes insufficient due to the voltage drop, it is possible to suppress display ON and OFF of the driving thin film transistor 43 not operating as predetermined.

  In the above-described embodiment, the configuration in which any one of the common power supply line 33 and the scanning line 31 is provided facing the back surface 11b side of the substrate 11 is described. However, the present invention is not limited to this. 11, the common power supply line 33 and the scanning line 31 may be provided so as to face the back surface 11 b side of the substrate 11.

In the case where a plurality of types of wirings are provided on the back surface 11b side of the substrate 11 as described above, for example, the signal shown in FIG. 2B is used so that an insulating film need not be interposed between the plurality of types of wirings. Providing wiring parallel to each other like the line 32 and the common power supply line 33 is preferable from the viewpoint of simplification of the process and reduction in thickness.
Therefore, when both the common power supply line 33 and the scanning line 31 described above are provided facing the back surface 11 b side of the substrate 11, for example, the common power supply line 33 is preferably arranged in parallel with the scanning line 31. It is.

Moreover, although the said embodiment demonstrated the structure which light emission of the organic electroluminescent apparatus 100 radiate | emits from the board | substrate 11 side in which the thin-film transistors 42 and 43 were provided, it is not limited to this. 12 shows a configuration in which the common power supply line 33 is provided facing the back surface 11b side of the substrate 11, and the organic EL device 100 emits light on the side of the sealing substrate 60 opposite to the substrate 11 on which the thin film transistors 42 and 43 are provided. It is a schematic sectional drawing of the display apparatus 10 radiate | emitted from. 13 shows a configuration in which the scanning line 31 is provided facing the back surface 11b side of the substrate 11, and the light emission of the organic EL device 100 is opposite to the substrate 11 on which the thin film transistors 42 and 43 are provided. It is a schematic sectional drawing of the display apparatus 10 radiate | emitted from the side. Further, FIG. 14 shows a configuration in which both the common power supply line 33 and the scanning line 31 are provided facing the back surface 11b side of the substrate 11, and the light emission of the organic EL device 100 is the substrate 11 provided with the thin film transistors 42 and 43. It is a schematic sectional drawing of the display apparatus 10 radiate | emitted from the reverse sealing substrate 60 side.
As shown in these drawings, since the light emitted from the organic EL device 100 is emitted from the sealing substrate 60 side, the present invention can be applied to the display device 10 having a large aperture ratio.

  Moreover, in the said embodiment, although the display apparatus 10 in which the organic EL apparatus 100 is provided as a light emission part was illustrated, this invention is applicable also to the display apparatus 10 provided with other light emission parts, such as a liquid crystal display panel. .

  DESCRIPTION OF SYMBOLS 1 ... Pixel part, 10 ... Display device, 11 ... Substrate, 11a ... Front surface (one surface), 11b ... Back surface (the other surface), 11e ... Recess, 31 ... Scanning line (wiring), 31a ... First wiring portion 31b ... second wiring part, 31c ... third wiring part, 32 ... signal line (wiring), 33 ... power supply line (wiring), 33a ... first wiring part, 33b ... second wiring part, 33c ... third wiring 40, light emitting unit

Claims (5)

A light emitting portion is provided for each of the plurality of pixel portions on one surface side of the substrate,
Corresponding to the positions of the plurality of pixel portions, a plurality of types of wirings are provided on the substrate in a matrix to transmit the power related to light emission of the light emitting portions,
At least a part of at least one type of the plurality of types of wirings is provided to face the other surface of the substrate.   The at least one wiring includes a first wiring portion provided on one surface side of the substrate, a second wiring portion provided facing the other surface side of the substrate, and penetrating the substrate in the thickness direction. The display device according to claim 1, further comprising: a third wiring portion provided to connect the first wiring portion and the second wiring portion.   The display device according to claim 2, wherein the second wiring portion is provided so as to protrude from the other surface of the substrate.   The display device according to claim 3, wherein the second wiring part is formed with a larger area than the first wiring part.   The display device according to claim 2, wherein the second wiring portion is provided substantially flush with the other surface of the substrate in a recess formed on the other surface of the substrate.

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