JP4830328B2 - Light emitting device - Google Patents

Description

  The present invention relates to a light emitting device including a light emitting element such as an organic EL element.

  An organic electroluminescence (EL / Electroluminescence) device, etc. as an exposure head in a display device used in an electronic device such as a mobile phone, a personal computer or a PDA (Personal Digital Assistants), or an image forming device such as a digital copying machine or a printer The light emitting device has attracted attention. In constructing this type of light emitting device for color, conventionally, the material constituting the light emitting layer is changed for each pixel so that light of each color is emitted from each pixel.

On the other hand, an optical resonator is formed between the lower reflective layer formed on the lower layer side of the light emitting layer and the upper reflective layer formed on the upper layer side of the light emitting layer, and the thickness of the anode made of ITO A technique has been proposed in which the optical length of the optical resonator is changed for each pixel by changing the light to extract light of each color from the light emitted from the light emitting element (see, for example, Patent Document 1).
Japanese Patent No. 2797883

  However, by changing the material constituting the light emitting layer for each pixel so that light of each color is emitted from each pixel, the life of the light emitting element for each color is long and short. Since the lifetime of the entire light emitting device is determined by the light emitting element having a short color, there is a problem that the lifetime is short. Moreover, since it is necessary to arrange different types of materials for each pixel, there is a problem that productivity is low.

  Further, as in the technique disclosed in Patent Document 1, when the optical length of the optical resonator is changed for each pixel by changing the thickness of the anode made of ITO, the patterning process using the photolithography technique is performed three times. There is a problem that productivity is low.

  In view of the above problems, an object of the present invention is to provide a light-emitting device that can extend the lifetime of the entire device and can be produced efficiently.

In order to solve the above problems, the present invention, in a light emitting device including a plurality of pixels each having a light emitting element formed of an organic functional layer including at least a light emitting layer, among the plurality of pixels, the first pixel is first The second pixel corresponds to a second color, and the light emitting element includes the organic functional layer, a lower reflective layer formed on a lower layer side of the organic functional layer, and the organic functional layer. An optical resonator including an upper reflective layer formed on the upper layer side, and a layer included in the organic functional layer provided in the first pixel is provided in the second pixel. The layer included in the organic functional layer is made of the same material as the layer included in the organic functional layer, and the thickness of the layer included in the organic functional layer provided in the first pixel is equal to the optical resonance provided in the first pixel. in that the optical length of the vessel is set so as to correspond to the first color The and corresponding color defined pixel, the thickness of the second layer included in the organic functional layer provided in the pixel, the optical of the optical resonator provided in the second pixel The length is set so as to correspond to the second color, whereby the corresponding color of the pixel is defined .

Further, in the present invention, in a light emitting device including a plurality of pixels each having a light emitting element formed of an organic functional layer including at least a light emitting layer, among the plurality of pixels, the first pixel corresponds to the first color, the The second pixel corresponds to the second color, and the light emitting element is formed on the organic functional layer, a lower reflective layer formed on the lower layer side of the organic functional layer, and an upper layer side of the organic functional layer. A layer included in the organic functional layer provided in the first pixel is connected to the organic functional layer provided in the second pixel. The layer included in the organic functional layer provided in the first pixel so that the color emitted from the first pixel is the first color and is configured of the same material as the included layer. the thickness is set, the color emitted from the second pixel, I said second color As, wherein the thickness of the layer included in the organic functional layer provided on the second pixel is set.

  In the present invention, each of the plurality of pixels corresponds to red, green, and blue, but the material of the organic functional layer constituting the light emitting element is common regardless of the corresponding color, and corresponds to any color. Whether to do this is determined by the thickness of the layer included in the organic functional layer. That is, in the present invention, an optical resonator is formed in each pixel, and the optical length of the optical resonator is a length corresponding to any of red light, green light, and blue light depending on the thickness of the layer included in the organic functional layer. Set to Therefore, regardless of which color the pixel corresponds to, the lifetime of each light emitting element is substantially equal, so that the lifetime of the entire light emitting device can be extended. Further, when the light emitting device is manufactured, the same material is used between the pixels, so that productivity can be improved. Furthermore, since the organic functional layer can be formed by a droplet discharge method called an ink jet method, the amount and the number of droplets discharged to the pixel can be arbitrarily and easily changed. Therefore, compared with the case where the thickness of the anode made of ITO is changed, the thickness of the organic functional layer can be easily changed for each pixel, and the productivity is high.

  In the present invention, when the organic functional layer includes the light-emitting layer and the organic layer, the pixel is configured such that the color emitted from each pixel is one of red light, green light, and blue light. The thickness of the light emitting layer or the organic layer is set every time.

In the present invention, the thickness of the layer included in the organic functional layer is preferably set to the following relationship: red light pixel ≧ green light pixel ≧ blue light pixel.

  In the present invention, a red color filter is formed on the light emitting side of the red pixel, a green color filter is formed on the light emitting side of the green pixel, and a blue color filter is disposed on the blue pixel. Preferably it is. The color purity of the light emitted from each pixel configured in this way can be further increased.

  In the present invention, the organic functional layer is preferably formed by discharging a liquid droplet of an organic material to each pixel and then fixing it. That is, in forming the organic functional layer, it is preferable that a liquid material is discharged to each pixel by a droplet discharge method called an ink jet method or the like, and then dried and fixed.

  Embodiments of the present invention will be described below with reference to the drawings. In the drawings used for the following description, the scales are different for each layer and each member in order to make each layer and each member large enough to be recognized on the drawing.

[Embodiment 1]
(Basic structure of light emitting device)
FIG. 1 is a cross-sectional view schematically showing a configuration of an organic EL element (light emitting element) used in an organic EL device (light emitting device) to which the present invention is applied. 2 (a), 2 (b), and 2 (c) are explanatory diagrams showing a spectrum of light internally emitted by the organic EL element shown in FIG. 1, an explanatory diagram showing a spectrum of light extracted by an optical resonator, and It is explanatory drawing which shows the transmission characteristic of a color filter.

  In FIG. 1, an organic EL device 1 according to this embodiment is a top emission type device that emits display light toward the side opposite to the substrate 11 side, and is red (R), green (G), and blue (B). The organic EL element 10 is formed in any of the pixels 100 (R), (G), and (B). The organic EL element 10 includes a transparent pixel electrode 12 (anode) made of ITO or the like, a hole injection layer 13 (organic functional layer), a light emitting layer 14 (organic functional layer), a magnesium-silver alloy on the upper layer side of the substrate 11. The transflective counter electrode 15 (cathode) made of is laminated in this order. In addition, on the upper layer side of the counter electrode 18, a transparent substrate 20 on which red (R), green (G), and blue (B) color filters 21 (R), (G), and (B) are formed is an epoxy. Bonded by a transparent adhesive layer 30 of the system. A light shielding film 22 is formed between the color filters 21 (R), (G), and (B).

  Further, a light reflection layer 19 (total reflection layer) such as silver or aluminum is formed between the substrate 11 and the pixel electrode 12, and a lower-layer side reflection layer made of the light reflection layer 19 and the counter electrode 15. An optical resonator 40 is formed between the upper reflective layer.

  Here, the hole injection layer 13 and the light emitting layer 14 used in the organic EL element 10 are made of the same material in any of the pixels 100 (R), (G), and (B). 10 emits light having a spectrum as shown by a solid line L1 in FIG.

However, in this embodiment, the thickness (unit: nm) of each layer in each pixel 100 (R), (G), (B) is as follows:
Pixel 100 (R) Pixel 100 (G) Pixel 100 (B)
Counter electrode 15 10 10 10
Light emitting layer 14 10 50 100
Hole injection layer 13 50 50 50
Pixel electrode 12 150 150 150
Light reflecting layer 19 200 200 200
The counter electrode 15, the hole injection layer 13, the pixel electrode 12, and the light reflection layer 19 have the same thickness between the pixels, but the thickness of the light emitting layer 14 is
Pixel 100 (R)> Pixel 100 (G)> Pixel 100 (B)
It is. Therefore, the optical length of the optical resonator in each pixel 100 (R), (G), (B) is different in each pixel 100 (R), (G), (B). In other words, the thickness of the light emitting layer 14 is adjusted so that the optical length of the optical resonator is emitted from each pixel 100 (R), (G), (B) with a predetermined color.

(Production method)
FIG. 3 is an explanatory diagram of the droplet discharge method. In manufacturing the light emitting device 1, in this embodiment, the counter electrode 15, the pixel electrode 12, the light reflection layer 19, and the like are formed by a semiconductor process such as a film forming process such as a sputtering method or a vacuum evaporation method, or a patterning process using a photolithography technique. Although formed by a process, the hole injection layer 13 and the light emitting layer 14 are formed by a droplet discharge method called an inkjet method or the like.

  In this droplet discharge method, as shown in FIG. 3, a liquid material M of a material constituting the hole injection layer 13 or the light emitting layer 14 is discharged as a droplet M0 from a droplet discharge head 50 and then dried. In this method, the hole injection layer 13 and the light emitting layer 14 are fixed. At that time, a partition wall 55 called a bank is formed around each of the pixels 100 (R), (G), and (B) so that the discharged droplets M0 and liquid matter do not protrude to the periphery.

  In adopting such a method, the hole injection layer 13 uses, for example, 3,4-polyethylenediosithiophene / polystyrene sulfonic acid (PEDOT / PSS), which is a polyolefin derivative, as a hole injection material, and this is organic. It can be formed by discharging a dispersion obtained by dispersing a solvent as a main solvent to a predetermined region and then drying it. In addition, the material for forming the hole injection layer 13 is not limited to the above-described materials, and polyphenylene vinylene whose polymer precursor is polytetrahydrothiophenylphenylene, 1,1-bis- (4-N N-ditolylaminophenyl) cyclohexane or the like can also be used.

  Further, the material for forming the light emitting layer 14 is also a polymer material, for example, having a molecular weight of 1000 or more from the viewpoint of imparting a change in film thickness to the light emitting layer 14 when formed on the upper layer side of the unevenness forming layer 17. It is preferable to use a polymer material. Specifically, a polyfluorene derivative, a polyphenylene derivative, a polyvinyl carbazole, a polythiophene derivative, or a polymer material thereof, a perylene dye, a coumarin dye, a rhodamine dye such as rubrene, perylene, 9,10-diphenylanthracene, What doped tetraphenyl butadiene, Nile red, coumarin 6, quinacridone, etc. is used. As such a polymer material, a π-conjugated polymer material in which π electrons of a double bond are non-polarized on a polymer chain is also a conductive polymer, and thus has excellent light emitting performance. Preferably used. In particular, a compound having a fluorene skeleton in the molecule, that is, a polyfluorene compound is more preferably used. In addition to such materials, for example, a composition for an organic EL device disclosed in JP-A-11-40358, that is, a precursor of a conjugated polymer organic compound, and at least one kind for changing light emission characteristics A composition for an organic EL device comprising the above fluorescent dye can also be used as a light emitting layer forming material.

(Light emission operation)
In the organic EL element 10 configured as described above, when a current flows from the pixel electrode 12 to the counter electrode 15 through the hole injection layer 13 and the light emitting layer 14, the light emitting layer 14 emits light according to the amount of current at that time. The light emitted from the light emitting layer 14 passes through the counter electrode 15 and is emitted to the observer side, while the light emitted from the light emitting layer 14 toward the substrate 11 is formed in the lower layer of the pixel electrode 12. The light is reflected by the light reflecting layer 19, passes through the counter electrode 18, and is emitted to the observer side. At that time, the light emitted from the light emitting layer 14 is multiple-reflected between the lower reflective layer (light reflective layer 19) and the upper reflective layer (counter electrode 18) of the optical resonator 40, and the optical resonator 40 It is possible to improve the chromaticity of light whose optical length corresponds to an integral multiple of a quarter wavelength.

  Accordingly, the organic EL element 10 internally generates white light having a spectrum as indicated by a solid line L1 in FIG. 2A, but from the pixel 100 (R) corresponding to red (R), FIG. In FIG. 2B, red light having a spectrum indicated by a solid line LR1 is emitted, and red light having a spectrum indicated by a dotted line LG1 in FIG. 2B is emitted from the pixel 100 (G) corresponding to green (G). From the emitted pixel 100 (B) corresponding to blue (B), red light having a spectrum indicated by a one-dot chain line LB1 in FIG. 2B is emitted.

  Further, in this embodiment, a red color filter 21 (R) having a transmission characteristic indicated by a solid line LR2 in FIG. 2C is arranged on the light emitting side of the red (R) pixel 100 (R), and green ( A green color filter 21 (G) having a transmission characteristic indicated by a dotted line LG2 in FIG. 2C is arranged on the light emitting side of the G) pixel 100 (G), and the blue (B) pixel 100 (B). Since the blue color filter 21 (B) having a transmission characteristic indicated by a one-dot chain line LB2 in FIG. 2C is arranged on the light emitting side of FIG. 2C, each pixel 100 (R), (G), (B) Will emit light with high color purity.

(Effect of this embodiment)
As described above, in the present embodiment, each of the plurality of pixels 100 corresponds to red (R), green (G), and blue (B), but the hole injection layer 13 that constitutes the organic EL element 10. The material of the organic functional layer such as the light emitting layer 14 and the like is common regardless of the corresponding color, and which color corresponds is determined by the thickness of the layer included in the organic functional layer. That is, in this embodiment, the optical resonator 40 is configured in each pixel 100, and the optical length of the optical resonator 40 is any of red light, green light, and blue light depending on the thickness of the light emitting layer 14 included in the organic functional layer. Set to the length corresponding to. Therefore, regardless of which color the pixel 100 corresponds to, the lifetime of the organic EL element 10 is substantially equal, so that the lifetime of the entire organic EL device 1 can be extended.

  Further, since the same material is used between the pixels 100 when the organic EL device 1 is manufactured, productivity can be improved.

  Furthermore, since the light emitting layer 14 made of an organic functional layer can be formed by an ink jet method (by a droplet discharge method), the amount and number of droplets M0 discharged to the pixel 100 can be arbitrarily and easily changed. . Therefore, productivity is high compared with the case where the thickness of the anode made of ITO is changed.

[Embodiment 2]
FIG. 4 is a cross-sectional view schematically showing a configuration of an organic EL element (light emitting element) used in the organic EL device (light emitting device) according to Embodiment 2 of the present invention. FIG. 5 is an explanatory diagram showing a spectrum of light extracted by the optical resonator. Since the basic configuration of this embodiment and the third embodiment described later is the same as that of the first embodiment, the same reference numerals are given to portions having common functions, and description thereof is omitted.

  In FIG. 4, the organic EL device 1 of the present embodiment also has the red (R), green (G), and blue (B) pixels 100 (R), (G), and (B) as in the first embodiment. In addition, the organic EL element 10 is formed. In the organic EL element 10 of this embodiment, a hole transport layer 16 (organic functional layer) is formed instead of or in addition to the hole injection layer. That is, the organic EL element 10 includes a transparent pixel electrode 12 (anode) made of ITO or the like, a hole transport layer 16 (organic functional layer), a light emitting layer 14 (organic functional layer), magnesium − on the upper layer side of the substrate 11. A transflective counter electrode 15 (cathode) made of a silver alloy is laminated in this order. In addition, on the upper layer side of the counter electrode 18, a transparent substrate 20 on which red (R), green (G), and blue (B) color filters 21 (R), (G), and (B) are formed is an epoxy. Bonded by a transparent adhesive layer 30 of the system. A light shielding film 22 is formed between the color filters 21 (R), (G), and (B).

  Further, a light reflection layer 19 (total reflection layer) such as silver or aluminum is formed between the substrate 11 and the pixel electrode 12, and a lower-layer side reflection layer made of the light reflection layer 19 and the counter electrode 15. An optical resonator 40 is formed between the upper reflective layer.

  Here, the hole transport layer 16 and the light emitting layer 14 used in the organic EL element 10 are made of the same material in any of the pixels 100 (R), (G), and (B). 10 emits white light.

However, in this embodiment, the thickness (unit: nm) of each layer in each pixel 100 (R), (G), (B) is as follows:
Pixel 100 (R) Pixel 100 (G) Pixel 100 (B)
Counter electrode 15 10 10 10
Light emitting layer 14 50 50 50
Hole transport layer 16 100 50 10
Pixel electrode 12 150 150 150
Light reflecting layer 19 200 200 200
The counter electrode 15, the light emitting layer 14, the pixel electrode 12, and the light reflecting layer 19 have the same thickness between pixels, but the thickness of the hole transport layer 16 is
Pixel 100 (R)> Pixel 100 (G)> Pixel 100 (B)
It is. Therefore, the optical length of the optical resonator in each pixel 100 (R), (G), (B) is different in each pixel 100 (R), (G), (B). In other words, the thickness of the hole transport layer 16 is adjusted so that the optical length of the optical resonator emits predetermined color light from each of the pixels 100 (R), (G), and (B).

  Therefore, in this embodiment, the organic EL element 10 generates white light internally, but red light having a spectrum indicated by a solid line LR1 in FIG. 5 is emitted from the pixel 100 (R) corresponding to red (R). The red light having the spectrum indicated by the dotted line LG1 in FIG. 5 is emitted from the emitted pixel 100 (G) corresponding to green (G), and from the pixel 100 (B) corresponding to blue (B), Red light having a spectrum indicated by a one-dot chain line LB1 in FIG. 5 is emitted.

  Further, in this embodiment, as in the first embodiment, the red color filter 21 (R) having the transmission characteristics indicated by the solid line LR2 in FIG. ) And a green color filter 21 (G) having a transmission characteristic indicated by a dotted line LG2 in FIG. 2C is arranged on the light emitting side of the green (G) pixel 100 (G), and blue (B ) Of the pixel 100 (B) is provided with a blue color filter 21 (B) having a transmission characteristic indicated by an alternate long and short dash line LB2 in FIG. 2C, so that each pixel 100 (R), From (G) and (B), light with high color purity is emitted.

  As described above, in this embodiment, the optical resonator 40 is configured in each pixel 100, and the optical length of the optical resonator 40 is set to red light, green light, blue, depending on the thickness of the hole transport layer 16 included in the organic functional layer. Set to a length corresponding to one of the lights. Therefore, regardless of which color the pixel 100 corresponds to, the lifetime of the organic EL element 10 is substantially equal, so that the lifetime of the entire organic EL device 1 can be extended. Further, since the same material is used between the pixels 100 when the organic EL device 1 is manufactured, productivity can be improved. Furthermore, since the hole transport layer 16 made of an organic functional layer can be formed by the ink jet method (by the droplet discharge method), the amount and number of droplets M0 discharged to the pixels 100 can be arbitrarily and easily changed. Can do. Therefore, the same effects as those of the first embodiment can be obtained, such as higher productivity than the case of changing the thickness of the anode made of ITO.

[Embodiment 3]
FIG. 6 is a cross-sectional view schematically showing a configuration of an organic EL element (light emitting element) used in an organic EL device (light emitting device) according to Embodiment 3 of the present invention. FIG. 7 is an explanatory diagram showing a spectrum of light extracted by the optical resonator.

  In FIG. 6, the organic EL device 1 of the present embodiment also has a transparent pixel electrode 12 (anode) made of ITO or the like, a hole injection layer on the upper layer side of the substrate 11, as in the first embodiment. 13 (organic functional layer), light emitting layer 14 (organic functional layer), and transflective counter electrode 15 (cathode) made of a magnesium-silver alloy is laminated in this order. In addition, on the upper layer side of the counter electrode 18, a transparent substrate 20 on which red (R), green (G), and blue (B) color filters 21 (R), (G), and (B) are formed is an epoxy. Bonded by a transparent adhesive layer 30 of the system. A light shielding film 22 is formed between the color filters 21 (R), (G), and (B).

  Further, a light reflection layer 19 (total reflection layer) such as silver or aluminum is formed between the substrate 11 and the pixel electrode 12, and a lower-layer side reflection layer made of the light reflection layer 19 and the counter electrode 15. An optical resonator 40 is formed between the upper reflective layer.

  Here, the hole injection layer 13 and the light emitting layer 14 used in the organic EL element 10 are made of the same material in any of the pixels 100 (R), (G), and (B). 10 emits white light.

However, in this embodiment, the thickness (unit: nm) of each layer in each pixel 100 (R), (G), (B) is as follows:
Pixel 100 (R) Pixel 100 (G) Pixel 100 (B)
Counter electrode 15 10 10 10
Light emitting layer 14 20 20 60
Hole injection layer 13 100 20 20
Pixel electrode 12 70 70 70
Light reflecting layer 19 200 200 200
The counter electrode 15, the pixel electrode 12, and the light reflecting layer 19 have the same thickness between the pixels.
The thickness of the hole injection layer 13 is
Pixel 100 (R)> Pixel 100 (G) = Pixel 100 (B)
The thickness of the light emitting layer 14 is
Pixel 100 (R) = Pixel 100 (G) <Pixel 100 (B)
The sum of the thickness of the hole injection layer 13 and the thickness of the light emitting layer 14 is
Pixel 100 (R)> Pixel 100 (B)> Pixel 100 (G)
It is. Therefore, the optical length of the optical resonator in each pixel 100 (R), (G), (B) is different in each pixel 100 (R), (G), (B). In other words, the thicknesses of the hole injection layer 13 and the light emitting layer 14 are adjusted so that the optical length of the optical resonator is emitted from each pixel 100 (R), (G), (B) with a predetermined color light. Has been.

  Therefore, in this embodiment, the organic EL element 10 generates white light internally, but red light having a spectrum indicated by a solid line LR1 in FIG. 7 is emitted from the pixel 100 (R) corresponding to red (R). The red light having the spectrum indicated by the dotted line LG1 in FIG. 7 is emitted from the emitted pixel 100 (G) corresponding to green (G), and from the pixel 100 (B) corresponding to blue (B), Red light having a spectrum indicated by a one-dot chain line LB1 in FIG. 7 is emitted.

  Further, in the present embodiment, as in the first embodiment, the red color filter 21 (R) having the transmission characteristics indicated by the solid line LR2 in FIG. 2C is disposed on the light emitting side of the red (R) pixel 100 (R). ) And a green color filter 21 (G) having a transmission characteristic indicated by a dotted line LG2 in FIG. 2C is arranged on the light emitting side of the green (G) pixel 100 (G), and blue (B ) Of the pixel 100 (B) is provided with a blue color filter 21 (B) having a transmission characteristic indicated by an alternate long and short dash line LB2 in FIG. 2C, so that each pixel 100 (R), From (G) and (B), light with high color purity is emitted.

  Thus, in this embodiment, the optical resonator 40 is configured in each pixel 100, and the optical length of the optical resonator 40 is set to red light, depending on the thickness of the hole injection layer 13 and the light emitting layer 14 included in the organic functional layer. The length corresponding to either green light or blue light is set. Therefore, regardless of which color the pixel 100 corresponds to, the lifetime of the organic EL element 10 is substantially equal, so that the lifetime of the entire organic EL device 1 can be extended. Further, since the same material is used between the pixels 100 when the organic EL device 1 is manufactured, productivity can be improved. Further, since the hole injection layer 13 and the light emitting layer 14 made of an organic functional layer can be formed by an inkjet method (by a droplet discharge method), the amount and number of droplets M0 discharged to the pixel 100 can be arbitrarily set, and Can be easily changed. Therefore, the same effects as those of the first embodiment can be obtained, such as higher productivity than the case of changing the thickness of the anode made of ITO.

[Other embodiments]
In the above embodiment, the top emission type that emits display light toward the side opposite to the substrate 11 has been described as an example. However, the present invention may be applied to a bottom emission type that emits display light toward the substrate. Good.

[Example of application to display devices]
The organic EL device 1 to which the present invention is applied can be used as a passive matrix display device or an active matrix display device. Among these display devices, the active matrix display device is configured to have the electrical configuration shown in FIG.

  FIG. 8 is a block diagram showing an electrical configuration of an active matrix organic EL device. In FIG. 8, in the organic EL device 1, a plurality of scanning lines 63, a plurality of data lines 64 extending in a direction intersecting with the extending direction of the scanning lines 63, and the data lines 64 are arranged in parallel. A plurality of common power supply lines 65 and pixels 100 (light emitting areas) corresponding to the intersections of the data lines 64 and the scanning lines 63 are configured, and the pixels 100 are arranged in a matrix in the image display area. A data line driving circuit 51 including a shift register, a level shifter, a video line, and an analog switch is configured for the data line 64. A scanning line driving circuit 54 including a shift register and a level shifter is configured for the scanning line 63. Each pixel 100 holds a pixel switching thin film transistor 6 to which a scanning signal is supplied to the gate electrode via the scanning line 63 and an image signal supplied from the data line 64 via the thin film transistor 6. The storage capacitor 33, the current control thin film transistor 7 to which the image signal held by the storage capacitor 33 is supplied to the gate electrode 43, and the common supply line 65 when electrically connected to the common power supply line 65 through the thin film transistor 7 The organic EL element 10 into which a drive current flows from the electric wire 65 is configured. In the organic EL device 1, each pixel 100 corresponds to one of red (R), green (G), and blue (B).

[Other embodiments]
In the above embodiment, an organic EL element is used as a light emitting element, but the present invention may be applied to a light emitting device using another light emitting element. In any case, the technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

[Example of mounting on electronic devices]
A light-emitting device to which the present invention is applied can be used as a display device in various electronic devices such as a mobile phone, a personal computer, and a PDA. The light emitting device to which the present invention is applied can also be used as an exposure head in an image forming apparatus such as a digital copying machine or a printer.

It is sectional drawing which shows typically the structure of the organic EL element (light emitting element) used for the organic EL apparatus (light emitting apparatus) which concerns on Embodiment 1 of this invention. (A), (b), (c) is explanatory drawing which shows the spectrum of the light internally emitted by the organic EL element shown in FIG. 1, the explanatory drawing which shows the spectrum of the light extracted by the optical resonator, and the color filter It is explanatory drawing which shows the permeation | transmission characteristic. It is explanatory drawing of a droplet discharge method. It is sectional drawing which shows typically the structure of the organic EL element (light emitting element) used for the organic EL apparatus (light emitting apparatus) which concerns on Embodiment 2 of this invention. FIG. 5 is an explanatory diagram showing a spectrum of light extracted by an optical resonator in the organic EL device shown in FIG. 4. It is sectional drawing which shows typically the structure of the organic EL element (light emitting element) used for the organic EL apparatus (light emitting apparatus) which concerns on Embodiment 3 of this invention. FIG. 7 is an explanatory diagram showing a spectrum of light extracted by an optical resonator in the organic EL device shown in FIG. 6. 1 is a block diagram illustrating an electrical configuration of an active matrix organic EL device.

Explanation of symbols

1 .... Organic EL display device, 10 .... Organic EL element, 11 .... Substrate, 12 .... Pixel electrode, 13 .... Hole injection layer (organic functional layer), 14 .... Light emitting layer (organic functional layer), 15 .. Counter electrode (total reflection layer / upper layer side reflection layer), 19 .. Transflective film (lower layer reflection layer), 21 (R), (G), (B)... Color filter, 40. Optical resonator, 100 (R), (G), (B) .. pixel

Claims (4)

In a light emitting device including a plurality of pixels having a light emitting element composed of an organic functional layer including a hole injection layer and a light emitting layer,
Of the plurality of pixels, a first pixel corresponds to a first color, a second pixel corresponds to a second color,
The light-emitting element is an optical resonance composed of the organic functional layer, a lower-side reflective layer formed on the lower layer side of the organic functional layer, and an upper-side reflective layer formed on the upper layer side of the organic functional layer. Have a bowl,
The light emitting layer provided in the first pixel is made of the same material as the light emitting layer provided in the second pixel,
The thickness of the light emitting layer provided in the first pixel is set so that the optical length of the optical resonator provided in the first pixel corresponds to the first color. , The corresponding color of the pixel is defined,
The thickness of the light emitting layer provided in the second pixel is set so that the optical length of the optical resonator provided in the second pixel corresponds to the second color. , The corresponding color of the pixel is defined,
The light emitting layer provided in the first pixel and the light emitting layer provided in the second pixel are separated by a partition,
The upper reflective layer is formed continuously over the first pixel and the second pixel;
And the upper layer-side reflecting layer is not covering the partition wall,
The organic functional layer is formed by discharging a liquid droplet of an organic material for each of the plurality of pixels and fixing the organic material layer. In claim 1,
Of the plurality of pixels, a third pixel corresponds to a third color,
The first color is red light, the second color is green light, and the third color is blue light.
A light emitting device, wherein a thickness of the light emitting layer provided in each of the first to third pixels is set. 3. The thickness of the light emitting layer according to claim 1, wherein the thickness of the light emitting layer is set to the following relationship: the pixel corresponding to red light ≧ the pixel corresponding to green light ≧ the pixel corresponding to blue light. Light-emitting device. In any one of Claim 1 thru | or 3, a red color filter is formed in the light emission side of the said pixel corresponding to the said red light, and a green color filter is formed in the light emission side of the said pixel corresponding to the said green light, A light-emitting device, wherein a blue color filter is disposed for the pixel corresponding to the blue light.

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