WO2018173825A1

WO2018173825A1 - Light device

Info

Publication number: WO2018173825A1
Application number: PCT/JP2018/009438
Authority: WO
Inventors: 北原　弘昭; 崇人小山田
Original assignee: パイオニア株式会社
Priority date: 2017-03-21
Filing date: 2018-03-12
Publication date: 2018-09-27

Abstract

This light device (30) is provided with a light emitting device (10) and a sensor device (20) (a light-receiving element (220)). The light emitting device (10) is provided with a plurality of light emitting units (172) and light transmitting units (174). Each light emitting unit (172) comprises a semi-transmissive reflective layer (140), a first electrode (110), an organic layer (120) and a second electrode (130). Each light transmitting unit (174) comprises a semi-transmissive reflective layer (140) and an organic layer (120) that serves as an optical layer. The number of layers interposed between the semi-transmissive reflective layer (140) and the second electrode (130) of each light emitting unit (172) is larger than the number of layers contained in the organic layer (120) that serves as an optical layer. In addition, the film thickness from the semi-transmissive reflective layer (140) to the second electrode (130) of each light emitting unit (172) is different from the film thickness of the organic layer (120) that serves as an optical layer.

Description

Optical device

The present invention relates to an optical device.

In recent years, it has been studied to provide a light-emitting device using a light-transmitting organic light-emitting layer. For example, the light-emitting device described in Patent Document 1 includes a substrate, a first electrode, an organic layer, and a plurality of second electrodes. The first electrode and the organic layer are sequentially stacked on the substrate. The plurality of second electrodes are, for example, aluminum films, and are arranged in stripes on the organic layer. Light from the outside of the OLED can pass through the region between the adjacent second electrodes. Thereby, OLED has translucency.

Patent Document 2 describes that a light-emitting device having translucency by making an opaque electrode a stripe is used for a stop lamp of a vehicle.

Patent Document 3 describes providing a resonator structure inside an organic EL element by providing a translucent reflective layer in an organic EL element having a transparent electrode, an organic layer, and a metal electrode.

JP 2013-149376 A Japanese Patent Laying-Open No. 2015-195173 JP 2006-147598 A

As described above, in recent years, light-emitting devices having translucency have been developed. In certain applications (eg, automotive tail lamps), such light emitting devices may be used in conjunction with devices (eg, photosensors or imaging devices) having light receiving elements (eg, photodiodes (PD)). is there. In this case, it is necessary to suppress the erroneous detection of the light receiving element by the light emitted from the light emitting device as much as possible.

An example of a problem to be solved by the present invention is to suppress erroneous detection of a light receiving element due to light emitted from a light emitting device.

The invention according to claim 1 is a plurality of light emitting units having a transflective layer, a first electrode, an organic layer, and a second electrode;
A light-transmitting part located between the two light-emitting parts and having the transflective layer and the optical layer;
A light receiving element;
With
The number of layers positioned between the transflective layer of the light emitting unit and the second electrode is an optical device larger than the number of layers of the optical layer of the light transmitting unit.

The invention according to claim 2 is a light emitting unit having a transflective layer, a first electrode, an organic layer, and a second electrode;
A translucent part located between the two light emitting parts and having the transflective layer;
A light receiving element;
With
The first film thickness, which is the film thickness between the transflective layer and the second electrode in the light emitting part, is the film thickness of the optical layer where the translucent part is located on the transflective layer. The optical device is different from the second film thickness.

The above-described object and other objects, features, and advantages will be further clarified by a preferred embodiment described below and the following drawings attached thereto.

FIG. 3 is a diagram for explaining the optical device according to the first embodiment. 6 is a diagram for explaining an optical device according to Embodiment 2. FIG. 6 is a plan view of a light emitting device according to Embodiment 3. FIG. FIG. 3 is a cross-sectional view taken along line AA in FIG. 2. It is the figure which expanded the area | region enclosed with the dotted line (alpha) of FIG. It is the figure which expanded the area | region enclosed with the dotted line (beta) of FIG. It is a figure which shows an example of the emission spectrum of the 2nd surface side (light emission surface side) of a light-emitting device. It is a figure which shows an example of the spectral reflectance of the translucent part of the light-emitting device of the same structure as FIG. It is a figure which shows an example of the spectral transmittance of the same light transmission part as FIG. FIG. 6 is a cross-sectional view illustrating a configuration of a light emitting device according to Modification 1 of Embodiment 3. 6 is a cross-sectional view illustrating a configuration of a light emitting device according to Modification Example 1. FIG. It is a figure which shows an example of the emission spectrum of the 2nd surface side (light emission surface side). It is a figure which shows an example of the spectral reflectance of a translucent part. It is a figure which shows an example of the spectral transmittance of a translucent part. FIG. 10 is a cross-sectional view illustrating a configuration of a light emitting device according to Modification 2 of Embodiment 3. It is a figure which shows an example of the spectral reflectance of a translucent part. It is a figure which shows an example of the spectral transmittance of a translucent part. FIG. 10 is a cross-sectional view illustrating a configuration of a light emitting device according to Modification 3 of Embodiment 3. It is a figure which shows an example of the spectral reflectance of a translucent part. It is a figure which shows an example of the spectral transmittance of a translucent part.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

(Embodiment 1)
FIG. 1 is a diagram for explaining an optical device 30 according to the first embodiment. The optical device 30 includes the light emitting device 10 and the sensor device 40 (light receiving element 420).

The light emitting device 10 includes a substrate 100, a plurality of light emitting units 172, and a plurality of light transmitting units 174. The substrate 100 has a first surface 100a and a second surface 100b. The second surface 100b is on the opposite side of the first surface 100a. The plurality of light emitting units 172 are located on the first surface 100 a side of the substrate 100. Each of the plurality of light transmitting portions 174 is located between the adjacent light emitting portions 172. The light emitting device 10 has translucency due to the plurality of translucent portions 174.

The light-emitting device 10 shown in FIG. 1 has the same configuration as the light-emitting device 10 described in detail later with reference to FIG. As will be described in detail later with reference to FIG. 3 and subsequent drawings, light from the plurality of light emitting units 172 is mainly output from the second surface 100 b of the substrate 100. In particular, in the present embodiment, the amount of light emitted from each light emitting unit 172 and leaking from the first surface 100a side of the substrate 100 is suppressed.

The sensor device 40 is provided around the light emitting device 10. In the example shown in FIG. 1, the sensor device 40 is in front of the first surface 100 a of the substrate 100, specifically, the first surface 100 a side when viewed from a direction parallel to the substrate 100 and the substrate 100. It is located in the position which does not overlap with the 1st surface 100a or the 2nd surface 100b when it sees from the direction perpendicular | vertical to. In another example, the sensor device 40 may be in front of the first surface 100a of the substrate 100, or may be in the side between the first surface 100a and the second surface 100b of the substrate 100. In still another example, the sensor device 40 may be obliquely in front of the second surface 100b of the substrate 100. Specifically, the second surface 100b of the substrate 100 when viewed from a direction parallel to the substrate 100. It may be located at a position that does not overlap the first surface 100a or the second surface 100b when viewed from the side and the direction perpendicular to the substrate 100.

The sensor device 40 performs optical sensing for acquiring information around the optical device 30. In the example shown in FIG. 1, the sensor device 40 includes a light emitting element 410 and a light receiving element 420. In one example, the sensor device 40 may be a distance measuring sensor, particularly a LiDAR (Light Detection And Ranging). In this example, the light emitting element 410 emits light toward the outside of the sensor device 40, and the light receiving element 420 receives light emitted from the light emitting element 410 and reflected by the object. In one example, the light emitting element 410 can be an element that can convert electrical energy into light energy, such as a laser diode (LD), and the light receiving element 420 can be an element that can convert light energy into electrical energy, such as It can be a photodiode (PD). The sensor device 40 can detect the distance from the sensor device 40 to the object based on the time from when light is emitted from the light emitting element 410 to when it is received by the light receiving element 420.

The light receiving element 420 of the sensor device 40 detects light from outside the sensor device 40. Therefore, in order to prevent erroneous detection of the light receiving element 420, it is desirable to suppress the light emitted from the light emitting device 10 from entering the light receiving element 420 as much as possible.

The light device 30 can be used for light emitting and light sensing applications, for example, a tail lamp with a distance measuring sensor of an automobile. In this example, the light emitting device 10 realizes a light emitting function, and the sensor device 40 realizes a light sensing function.

According to the configuration described above, erroneous detection of the light receiving element 420 due to light emitted from the light emitting device 10 can be suppressed. Specifically, as described above, in this embodiment, the amount of light emitted from each light emitting unit 172 and leaking from the first surface 100a side of the substrate 100 is suppressed. Therefore, it can suppress that the light emitted from the light-emitting device 10 injects into the sensor apparatus 40 (light receiving element 420). Therefore, erroneous detection of the light receiving element 420 due to light emitted from the light emitting device 10 can be suppressed.

In particular, in the present embodiment, even if the sensor device 40 (light receiving element 420) is in front of or obliquely in front of the first surface 100a of the substrate 100, erroneous detection of the light receiving element 420 due to light emitted from the light emitting device 10 is suppressed. Can do. As described above, in this embodiment, the amount of light emitted from each light emitting unit 172 and leaking from the first surface 100a side of the substrate 100 is suppressed. Therefore, the leakage of light emitted from the light emitting device 10 to the front or obliquely front side of the first surface 100a of the substrate 100 can be suppressed. Therefore, even when the sensor device 20 (light receiving element 420) is in front of or obliquely in front of the first surface 100a of the substrate 100, erroneous detection of the light receiving element 420 due to light emitted from the light emitting device 10 can be suppressed.

(Embodiment 2)
FIG. 2 is a diagram for explaining the optical device 30 according to the second embodiment, and corresponds to FIG. 1 of the first embodiment. The optical device 30 according to the present embodiment is the same as the optical device 30 according to the first embodiment except for the following points.

The sensor device 40 performs optical sensing for acquiring information around the optical device 30. In the example shown in FIG. 2, the sensor device 40 includes a plurality of light receiving elements 420. In one example, the sensor device 40 can be an imaging sensor. In this example, the plurality of light receiving elements 420 can be elements capable of converting an image into an electric signal, for example, a CCD (Charge Coupled Device) image sensor or a CMOS (Complementary Metal-Oxide-Semiconductor) image sensor. In one example, each light receiving element 420 can be an element that can convert light energy into electrical energy, such as a photodiode (PD). The sensor device 40 can detect an image of an object outside the sensor device 40 by using the plurality of light receiving elements 420.

The light receiving element 420 of the sensor device 40 detects light from outside the sensor device 40. Therefore, in order to prevent erroneous detection of the light receiving element 420, it is desirable to suppress the amount of light emitted from the light emitting device 10 and incident on the light receiving element 420 as much as possible.

The optical device 30 can be used for light emission and optical sensing, for example, a tail lamp with an image sensor of an automobile. In this example, the light emitting device 10 realizes a light emitting function, and the sensor device 40 realizes a light sensing function.

Also in the present embodiment, in the same manner as in the first embodiment, erroneous detection of the light receiving element 420 due to light emitted from the light emitting device 10 can be suppressed.

(Third embodiment)
FIG. 3 is a plan view of the light emitting device 10 according to the third embodiment. 4 is a cross-sectional view taken along the line AA in FIG. As illustrated in FIG. 3, the light emitting device 10 according to the embodiment includes a plurality of light emitting units 172 and a light transmitting unit 174. As shown in FIG. 4, the light emitting unit 172 includes a transflective layer 140, a first electrode 110, an organic layer 120, and a second electrode 130. As shown in FIG. 6, the translucent part 174 includes a transflective layer 140 and an optical layer 180. The number of layers positioned between the transflective layer 140 and the second electrode 130 of the light emitting unit 172 is larger than the number of layers of the optical layer 180. The film thickness (hereinafter referred to as the first film thickness) between the transflective layer 140 and the second electrode 130 of the light emitting unit 172 is the film thickness of the optical layer 180 (hereinafter referred to as the second film thickness). Is different. Hereinafter, the light emitting device 10 will be described in detail.

As described above, the light emitting device 10 includes a plurality of light emitting units 172. Each of the plurality of light emitting units 172 extends linearly (for example, linearly). In the example shown in the figure, the plurality of light emitting portions 172 extend in parallel to each other. However, at least a part of a certain light emitting unit 172 does not have to be parallel to the light emitting unit 172 located adjacent thereto.

The plurality of light emitting portions 172 are formed using the substrate 100. The light emitting unit 172 is a bottom emission type, and emits light from the second surface 100 b of the substrate 100 to the outside. However, the light emitting unit 172 may be a top emission type.

The substrate 100 is formed of a light-transmitting material such as glass or a light-transmitting resin. The substrate is, for example, a polygon such as a rectangle. The substrate 100 may have flexibility. In the case where the substrate 100 has flexibility, the thickness of the substrate 100 is, for example, not less than 10 μm and not more than 1000 μm. In particular, when the substrate 100 having glass is made flexible, the thickness of the substrate 100 is, for example, 200 μm or less. When the substrate 100 formed of a resin material is flexible, the material of the substrate 100 is, for example, at least PEN (polyethylene naphthalate), PES (polyethersulfone), PET (polyethylene terephthalate), and polyimide. One. In the case where the substrate 100 is formed of a resin material, an inorganic barrier layer such as SiN _x or SiON is formed on at least the light emitting surface (preferably both surfaces) of the substrate 100 in order to suppress moisture from passing through the substrate 100. Is preferably formed.

The light emitting unit 172 is formed on the first surface 100a of the substrate 100, and includes the first electrode 110, the organic layer 120, and the second electrode 130 as described above.

The first electrode 110 is formed of a transparent conductive film. This transparent conductive film is a metal-containing material, for example, a metal oxide such as ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), IWZO (Indium Tungsten Zinc Oxide), or ZnO (Zinc Oxide). The refractive index of the material of the transparent electrode is, for example, 1.5 or more and 2.2 or less. The thickness of the transparent electrode is, for example, 10 nm or more and 500 nm or less. The transparent electrode is formed using, for example, a sputtering method or a vapor deposition method. The transparent electrode may be a carbon nanotube, a conductive organic material such as PEDOT / PSS, or a thin metal electrode.

In the example shown in the figure, the first electrode 110 is formed in and around the region to be the plurality of light emitting portions 172, but is not formed in other regions. For example, the first electrode 110 is not formed on the entire light-transmitting portion 106 described later and a part of the light-transmitting portion 104 in the width direction of the light-emitting portion 172. However, the 1st electrode 110 may be formed also in the translucent part 104,106 mentioned later. In this case, the first electrodes 110 included in the plurality of light emitting units 172 are connected to each other.

The organic layer 120 is located between the first electrode 110 and the second electrode 130 and has a plurality of layers. One of the plurality of layers is a light emitting layer 123 described later. The organic layer 120 is formed continuously with the light emitting portion 172 and the light transmitting portion 174. However, as will be described later with reference to FIGS. 5 and 6, the number of layers of the organic layer 120 (that is, the film thickness) positioned in the light emitting portion 172 is the number of layers of the organic layer 120 positioned in the light transmitting portion 174 ( Film thickness).

The second electrode 130 has a metal layer, for example, and has light reflectivity. The metal layer included in the second electrode 130 is, for example, a layer made of a metal selected from the first group consisting of Al, Au, Ag, Pt, Mg, Sn, Zn, and In, or the first group. A layer made of an alloy of selected metals. The second electrode 130 is formed using, for example, a vacuum evaporation method.

In addition, an insulating film 160 is formed on the first electrode 110. In the example shown in FIG. 4, the insulating film 160 covers the end of the first electrode 110, and has an opening 162 in a region of the first electrode 110 that should become the light emitting portion 172. The insulating film 160 is formed by photolithography using a material in which a photosensitive substance is contained in polyimide or the like, for example. The insulating film 160 is formed after the first electrode 110 is formed and before the organic layer 120 is formed. The cross-sectional shape of the insulating film 160 becomes narrower as the distance from the first surface 100a of the substrate 100 increases. An example of the cross-sectional shape of the insulating film 160 is a substantially trapezoid. The two side surfaces (including the inner side surface 152) of the insulating film 160 are inclined in a direction facing the substrate 100.

The insulating film 160 may be a material other than the above, for example, an acrylic resin, an epoxy resin, PMMA (polymethyl methacrylate resin), a fluororesin, or a mixture or laminated film thereof. The insulating film 160 may be an inorganic insulating film such as SiO ₂ , SiN _x , or SiON.

The light emitting device 10 includes a light shielding unit 102 and light transmitting

units

104 and 106. The light transmitting part 174 described above is an area where the light transmitting part 104 and the light transmitting part 106 are combined. The light shielding portion 102 is a region overlapping the second electrode 130. The light transmitting portion 104 is a region including the insulating film 160 among the regions between the plurality of light shielding portions 102. The light transmitting portion 106 is a region that does not include the insulating film 160 among the regions between the plurality of light shielding portions 102. Further, the translucent portion 106 does not overlap with the first electrode 110. In the example shown in the drawing, the organic layer 120 is not formed on at least a part of the light transmitting portion 106. The width of the light transmitting portion 104 is narrower than the width of the light transmitting portion 106. Further, the width of the light transmitting portion 106 may be wider or narrower than the width of the light shielding portion 102. When the width of the light shielding part 102 is 1, the width of the light transmitting part 104 is, for example, 0 or more (or more than 0) 0.2 or less, and the width of the light transmitting part 106 is, for example, 0.3 or more and 2 or less. The width of the light shielding part 102 is, for example, 50 μm or more and 500 μm or less, the width of the light transmitting part 104 is, for example, 0 μm or more (or more than 0 μm), 100 μm or less, and the width of the light transmitting part 106 is, for example, 15 μm or more and 1000 μm or less. .

The light emitting device 10 has a plurality of light transmitting portions 174. For this reason, the light-emitting device 10 has translucency. Further, the light emitting unit 172 overlaps the light shielding unit 102. For this reason, most of the light emitted from the light emitting unit 172 is radiated to the outside from the surface of the substrate 100 where the light emitting unit 172 is not formed (second surface 100b).

The light emitting device 10 further includes a first terminal 112, a first wiring 114, a second terminal 132, and a second wiring 134. The first terminal 112 and the second terminal 132 are terminals for connecting the light emitting unit 172 to an external drive circuit. The first wiring 114 connects the first terminal 112 to the first electrode 110, and the second wiring 134 connects the second wiring 134 to the second electrode 130. The first terminal 112, the first wiring 114, the second terminal 132, and the second wiring 134 are all formed on the first surface 100 a of 100.

Note that the light emitting device 10 may further include a sealing portion (not shown). This sealing part may have a configuration in which, for example, an inorganic film is laminated, or may have a metal layer such as an aluminum foil and an adhesive layer, or an adhesive layer may be formed on the above laminated film. You may have the structure which attached metal foil via.

FIG. 5 is an enlarged view of the area surrounded by the dotted line α in FIG. However, the film thickness ratio is different from that in FIG. In the example illustrated in FIG. 5, the organic layer 120 includes a first functional layer 121, a second functional layer 122, a light emitting layer 123, and a third functional layer 124 in this order from the first electrode 110 side. The first functional layer 121 is, for example, a hole injection layer, and the second functional layer 122 is, for example, a hole transport layer. The light emitting layer 123 includes a light emitting material, and the third functional layer 124 is, for example, an electron transport layer. However, the layer configuration of the organic layer 120 in the light emitting unit 172 is not limited to the example shown in FIG. For example, the organic layer 120 may have an electron blocking layer between the second functional layer 122 and the light emitting layer 123, or a hole blocking layer between the light emitting layer 123 and the third functional layer 124. It may be. The organic layer 120 is formed by using, for example, a vapor deposition method, but at least a part of the layer (for example, the first functional layer 121) may be formed by a coating method.

The light emitting device 10 has a transflective layer 140. The transflective layer 140 has a laminated structure in which a high refractive index layer 141 and a low refractive index layer 142 are laminated. In the example shown in FIG. 5, the transflective layer 140 has a high refractive index layer 141 and a low refractive index layer 142 that are repeated in this order in two layers. However, the transflective layer 140 may have three or more high refractive index layers 141 and low refractive index layers 142, or may have one layer each. The low refractive index layer 142 has a lower refractive index than the high refractive index layer 141. The material constituting the high refractive index layer 141 is preferably a dielectric such as TiO ₂ , Nb ₂ O ₅ , or Ta ₂ O ₅ , but may be a transparent conductor such as ITO or IZO. The low refractive index layer 142 is, for example, SiO ₂ or MgF ₂ , but may be other materials. The surface of the semi-transmissive reflective layer 140 that faces the substrate 100 is the high refractive index layer 141, and the surface of the semi-transmissive reflective layer 140 that faces the first electrode 110 is the low refractive index layer 142. The high refractive index layer 141 and the low refractive index layer 142 are formed using, for example, a sputtering method.

The transflective layer 140 is formed so as to reflect light of this wavelength when any wavelength (for example, peak wavelength) included in the emission spectrum of light emitted from the second surface 100b is λ. . For example, both the high refractive index layer 141 and the low refractive index layer 142 have an optical film thickness of 0.9 times or more and 1.1 times or less of λ / 4n. When the first electrode 110 is also designed as a part of the transflective layer 140, it is preferable that the optical film thickness of the first electrode 110 is also 0.9 times to 1.1 times λ / 4n.

In the light emitting unit 172, the transflective layer 140 is located between the first electrode 110 and the substrate 100. As shown in FIG. 5, in the light emitting unit 172, the layer between the transflective layer 140 and the light-reflective second electrode 130, specifically, the first electrode 110 and the organic layer 120 has a wavelength λ. A resonator structure 150 for light is configured. When the semitransparent reflective layer 140 of the optical thickness of the layer between the second electrode 130 and L _2, L ₂ satisfy the following equation.
m × 0.8 <2L / λ + φ / (2π) <m × 1.2 (1)
Where φ is a phase shift (in radians) in reflection, and m is 0 or a positive integer.

Thereby, the component of the wavelength λ in the light emitted from the light emitting unit 172 is strengthened. In addition, when using the light-emitting device 10 for the marker lamp (for example, stop lamp) of a vehicle, it is preferable that wavelength (lambda) is contained in the red wavelength range, for example.

FIG. 6 is an enlarged view of a region surrounded by a dotted line β in FIG. However, the film thickness ratio is different from that in FIG. The transflective layer 140 is also formed on the light transmitting part 174. The transflective layer 140 located in the light emitting part 172 and the transflective layer 140 located in the translucent part 174 are continuous with each other to form one transflective layer 140.

On the transflective layer 140, a layer (optical layer 180) through which light passes is formed. The thickness (second film thickness) of the optical layer 180 is different from the thickness (first film thickness) of the layer located between the transflective layer 140 and the second electrode 130 in the light emitting unit 172. Specifically, the optical layer 180 is adjusted so that the optical film thickness satisfies the following formula (2).
0.9λ (2m−1) / 4 <L1 <1.1λ (2m−1) / 4 (m is a positive integer) (2)

In order to suppress an increase in manufacturing steps, the optical layer 180 preferably includes at least one of the organic layers 120 and at least one of the first electrodes 110. For example, in the example shown in FIG. 6, the first electrode 110 is not formed on the transflective layer 140 in the light transmitting portion 174, and a part of the organic layer 120 is not formed. . In other words, the optical layer 180 is composed of a part of the organic layer 120. For example, when the first functional layer 121 is formed by a coating method such as an inkjet method, and the second functional layer 122, the light emitting layer 123, and the third functional layer 124 are formed in this order by an evaporation method, the optical layer 180 is formed. Includes a second functional layer 122, a light emitting layer 123, and a third functional layer 124. The layer formed by the coating method can easily form a pattern as compared with the layer formed by the vapor deposition method. Therefore, preventing the first functional layer 121 from being formed in the light transmitting portion 174 (particularly the light transmitting portion 106) can cause the second functional layer 122, the light emitting layer 123, and the third functional layer 124 to be transparent. In particular, it can be easily performed as compared with the case where the light transmitting portion 106) is not formed. Note that at least one refractive index of the second functional layer 122, the light emitting layer 123, and the third functional layer 124 is larger than the refractive index of the low refractive index layer 142.

It is preferable that the layers common to the light emitting portion 172 and the light transmitting portion 174 are continuous. For example, in the example shown in FIGS. 4 to 6, the second functional layer 122, the light emitting layer 123, and the third functional layer 124 are continuous in the light emitting portion 172 and the light transmitting portion 174.

Next, a method for manufacturing the light emitting device 10 will be described. First, the first electrode 110 is formed on the substrate 100 using, for example, a vapor deposition method using a mask. Next, the insulating film 160 is formed using a photoresist method. Next, each layer of the organic layer 120 is formed. Next, the second electrode 130 is formed using, for example, an evaporation method using a mask. And a sealing part is provided.

In the present embodiment, the number of layers (that is, the optical film thickness) between the transflective layer 140 and the second electrode 130 in the light emitting unit 172 is the same as that of the optical layer 180 on the transflective layer 140 in the translucent unit 174. It is different from the number of layers (that is, optical film thickness). Therefore, the resonator structure 150 using the transflective layer 140 can be provided in the light emitting portion 172, and the optical filter using the transflective layer 140 can be provided in the light transmitting portion 174. By providing the resonator structure 150, the light emission unit 172 emits light with the wavelength λ. Further, by providing an optical filter using the transflective layer 140 in the light transmitting portion 174, light leaking to the second surface 100b side in the light transmitting portion 174 can be reduced.

In particular, when the optical layer 180 satisfies the above formula (2), the optical filter located in the light transmitting portion 174 functions as a filter that reflects at least a part (for example, 30% or more) of light having the wavelength λ. Accordingly, it is possible to particularly reduce light leaking to the second surface 100b side in the light transmitting portion 174.

FIG. 7 is a diagram illustrating an example of an emission spectrum on the second surface 100 b side (light emitting surface side) of the light emitting device 10. In the light emitting device 10, the substrate 100 is made of glass (refractive index 1.5). As shown in FIG. 5, the transflective layer 140 has two high refractive index layers 141 and two low refractive index layers 142. The high refractive index layer 141 is Nb ₂ O ₅ (refractive index 2.3) having a thickness of 68 nm, and the low refractive index layer 142 is SiO ₂ (refractive index 1.5) having a thickness of 105 nm. The electrode 110 is ITO (refractive index 1.9) having a thickness of 85 nm. The first functional layer 121 of the organic layer 120 is a coating-type hole injection material (refractive index 1.7) having a thickness of 65 nm. The second functional layer 122 is formed using a hole transporting material, and the third functional layer 124 is formed using an electron transporting material. The peak wavelength of the emission spectrum of the light emitting layer 123 (that is, the peak wavelength of the emission spectrum of the light emitting device 10) is about 630 nm. For this reason, the optical film thicknesses of the high refractive index layer 141, the low refractive index layer 142, and the first electrode 110 are about λ / 4. The sum of the optical film thickness of the first electrode 110 and the optical film thickness of the organic layer 120 (refractive index 1.7 to 1.9) is 1.19λ, which satisfies the above formula (1). The second electrode 130 is an Al film having a thickness of 90 nm.

As shown in FIG. 7, the light emitting device 10 has a light emission intensity of the wavelength λ approximately three times that of the light emitting device that does not have the transflective layer 140 (that is, does not have the resonator structure 150). It can be seen that the brightness is increased.

FIG. 8 shows an example of the spectral reflectance of the light transmitting part 174 of the light emitting device 10 having the same structure as FIG. FIG. 9 shows an example of the spectral transmittance of the same light transmitting portion 174 as in FIG. In the light transmitting portion 174, the optical layer 180 includes the second functional layer 122, the light emitting layer 123, and the third functional layer 124, and the optical film thickness is 0.76λ. FIG. 8 shows that the light transmitting portion 174 has a high reflectance at the wavelength λ (about 75% in the example shown in FIG. 8). On the other hand, in most of the visible light region, the transmissivity of the translucent part 174 is 50% or less, so the visible light transmittance is 50% or more. For this reason, the translucency of the translucent part 174 is sufficiently ensured.

(Modification 1)
FIG.10 and FIG.11 is sectional drawing which shows the structure of the light-emitting device 10 which concerns on the modification 1 of 3rd Embodiment. FIG. 10 corresponds to FIG. 5 of the third embodiment, and FIG. 11 corresponds to FIG. 6 of the third embodiment. The light emitting device 10 according to the present modification is the light emitting device 10 according to the third embodiment, except that the transflective layer 140 has one high refractive index layer 141 and one low refractive index layer 142. It is the same composition as.

FIG. 12 is a diagram illustrating an example of an emission spectrum on the second surface 100b side (light emitting surface side) of the light emitting device 10 according to the present modification. FIG. 13 shows an example of the spectral reflectance of the light transmitting part 174 of the light emitting device 10 according to this modification, and FIG. 14 shows an example of the spectral transmittance of the light transmitting part 174. The specific configuration of each layer of the light-emitting device 10 having these spectra is the same as that of the light-emitting device 10 used in FIGS.

As can be seen from these drawings, even when the high refractive index layer 141 and the low refractive index layer 142 are provided one by one, the light emitting device 10 has a light emission intensity of wavelength λ in light emission toward the second surface 100b. The translucent portion 174 has a high reflectance (for example, 50% or more) at the wavelength λ, and the translucent portion 174 has a sufficiently high visible light transmittance (for example, 70 higher than that of the embodiment). %more than).

(Modification 2)
FIG. 15 is a cross-sectional view illustrating a configuration of a light-emitting device 10 according to Modification 2 of the third embodiment, and corresponds to FIG. 6 of the third embodiment. In the light emitting device 10 according to this modification, the organic layer 120 is not formed in the light transmitting portion 174, and the first electrode 110 is formed instead. In other words, the optical layer 180 is the first electrode 110. Except for the point which is comprised, it is the structure similar to the light-emitting device 10 which concerns on 3rd Embodiment.

FIG. 16 shows an example of the spectral reflectance of the light transmitting part 174 of the light emitting device 10 according to this modification, and FIG. 17 shows an example of the spectral transmittance of the light transmitting part 174. The specific configuration of each layer of the light-emitting device 10 having these spectra is the same as that of the light-emitting device 10 used in FIGS.

As can be seen from these drawings, even if the optical layer 180 is composed of the first electrode 110, the light transmitting portion 174 has a high reflectance (for example, 74% or more) at the wavelength λ, and the light transmitting portion. The visible light transmittance of 174 is sufficiently secured (for example, 43% or more). Although the transflective layer 140 has the resonator structure 150 and is not shown, the light emitting device 10 emits light with a wavelength λ in the light emitted to the second surface 100b side.

(Modification 3)
FIG. 18 is a cross-sectional view showing a configuration of a light emitting device 10 according to Modification 3 of the third embodiment, and corresponds to FIG. 6 of the third embodiment. The light emitting device 10 according to this modification has the same configuration as that of the light emitting device 10 according to modification 2, except that the high refractive index layer 141 and the low refractive index layer 142 are one layer each.

FIG. 19 shows an example of the spectral reflectance of the light transmitting part 174 of the light emitting device 10 according to this modification, and FIG. 20 shows an example of the spectral transmittance of the light transmitting part 174. The specific configuration of each layer of the light-emitting device 10 having these spectra is the same as that of the light-emitting device 10 used in FIGS.

As can be seen from these figures, even though the optical layer 180 is composed of the first electrode 110 and the high refractive index layer 141 and the low refractive index layer 142 are one layer at a time, the translucent portion 174 has a wavelength λ. It has a high reflectance (for example, 48% or more), and the visible light transmittance of the light transmitting portion 174 is sufficiently ensured (for example, 58% or more, which is higher than that of Modification 3). Although the transflective layer 140 has the resonator structure 150 and is not shown, the light emitting device 10 emits light with a wavelength λ in the light emitted to the second surface 100b side.

As mentioned above, although embodiment and the Example were described with reference to drawings, these are the illustrations of this invention, Various structures other than the above are also employable.

Hereinafter, examples of the reference form will be added.
1. A plurality of light emitting units having a transflective layer, a first electrode, an organic layer, and a second electrode;
A light-transmitting part located between the two light-emitting parts and having the transflective layer and the optical layer;
With
The light emitting device in which the number of layers positioned between the transflective layer of the light emitting unit and the second electrode is larger than the number of layers of the optical layer of the light transmitting unit.
2. A light emitting unit having a transflective layer, a first electrode, an organic layer, and a second electrode;
A translucent part located between the two light emitting parts and having the transflective layer;
With
The first film thickness, which is the film thickness between the transflective layer and the second electrode in the light emitting part, is the film thickness of the optical layer where the translucent part is located on the transflective layer. A light emitting device different from the second film thickness.
3. In the light-emitting device according to 1 or 2,
Equipped with a translucent substrate,
The transflective layer, the first electrode, the organic layer, the second electrode, and the optical layer are located on the substrate;
The first electrode has a light-transmitting property, and the second electrode has a light-reflecting property.
4). In the light emitting device according to the above 3,
The transflective layer includes a high refractive index layer and a low refractive index layer having a lower refractive index than the high refractive index layer.
5). In the light emitting device according to the above 4,
The light emitting device, wherein the optical layer includes a material having a refractive index larger than that of the low refractive index layer.
6). In the light-emitting device according to 4 or 5,
The light-emitting device in which the transflective layer of the light-emitting portion and the transflective layer of the translucent portion are continuous.
7). In the light emitting device according to 6 above,
The organic layer has a plurality of layers,
The light-emitting device, wherein the optical layer includes at least one of the organic layers and at least one of the first electrodes.
8). In the light emitting device according to the above 7,
The light emitting device, wherein the optical layer includes a part of the organic layer.
9. 9. The light emitting device according to 8 above,
The organic layer includes a first functional layer, a second functional layer, a third functional layer, and a light emitting layer having a light emitting material,
The light emitting device, wherein the optical layer includes the second functional layer, the third functional layer, and the light emitting layer.
10. 10. The light emitting device according to 9 above,
The light emitting device in which the second functional layer, the third functional layer, and the light emitting layer are continuous with the light transmitting portion and the light emitting portion.
11. In the light-emitting device according to 9 or 10,
A light emitting device in which the light emitting layer is located between the second functional layer and the third functional layer.
12 In the light emitting device according to any one of the above 9 to 11,
The light emitting device, wherein the first functional layer is a coating layer containing a hole injection material.
13. In the light-emitting device according to any one of 9 to 12,
The transflective layer is a light emitting device in which the high refractive index layer and the low refractive index layer are repeatedly positioned.
14 In the light-emitting device according to any one of 1 to 13,
The light-emitting device in which the reflectance with respect to the peak wavelength of the radiation spectrum of the said light emission part in the said translucent part is 30% or more.
15. 15. The light emitting device according to 14 above,
A light-emitting device that satisfies the following formula (1), where L ₁ is the optical film thickness of the optical layer and λ is any wavelength included in the emission spectrum of the light-emitting device.
0.9λ (2m−1) / 4 <L ₁ <1.1λ (2m−1) / 4 (m is a positive integer) (1)
16. 16. The light emitting device according to 15 above,
When the optical thickness of the layer located between the second electrode and the semitransparent reflective layer has a L _2,
A light emitting device satisfying the following formula (2).
m × 0.8 <2L / λ + φ / (2π) <m × 1.2 (2)
Where φ is a phase shift (in radians) in reflection, and n is 0 or a positive integer.
17. In the light emitting device according to 15 or 16,
The light emitting device, wherein λ is a peak wavelength of the emission spectrum.

This application claims priority based on Japanese Patent Application No. 2017-54484 filed on Mar. 21, 2017, the entire disclosure of which is incorporated herein.

Claims

A plurality of light emitting units having a transflective layer, a first electrode, an organic layer, and a second electrode;
A light-transmitting part located between the two light-emitting parts and having the transflective layer and the optical layer;
A light receiving element;
With
The optical device in which the number of layers positioned between the transflective layer and the second electrode of the light emitting unit is larger than the number of layers of the optical layer of the light transmitting unit.
A light emitting unit having a transflective layer, a first electrode, an organic layer, and a second electrode;
A translucent part located between the two light emitting parts and having the transflective layer;
A light receiving element;
With
The first film thickness, which is the film thickness between the transflective layer and the second electrode in the light emitting part, is the film thickness of the optical layer where the translucent part is located on the transflective layer. An optical device different from the second film thickness.
The optical device according to claim 1 or 2,
Equipped with a translucent substrate,
The transflective layer, the first electrode, the organic layer, the second electrode, and the optical layer are located on the substrate;
The optical device in which the first electrode has translucency and the second electrode has light reflectivity.
The optical device according to claim 3.
The transflective layer includes a high refractive index layer and a low refractive index layer having a refractive index lower than that of the high refractive index layer.
The optical device according to claim 4.
The optical device, wherein the optical layer includes a material having a refractive index larger than that of the low refractive index layer.
The optical device according to claim 4 or 5,
The optical device in which the transflective layer of the light emitting unit and the transflective layer of the translucent unit are continuous.
The optical device according to claim 6.
The organic layer has a plurality of layers,
The optical device includes at least one of the organic layers and at least one of the first electrodes.
The optical device according to claim 7.
The optical device, wherein the optical layer includes a part of the organic layer.
The optical device according to claim 8, wherein
The organic layer includes a first functional layer, a second functional layer, a third functional layer, and a light emitting layer having a light emitting material,
The optical device includes the second functional layer, the third functional layer, and the light emitting layer.
The optical device according to claim 9, wherein
The optical device in which the second functional layer, the third functional layer, and the light emitting layer are continuous with the light transmitting portion and the light emitting portion.
The optical device according to claim 9 or 10,
An optical device in which the light emitting layer is located between the second functional layer and the third functional layer.
The optical device according to any one of claims 9 to 11,
The optical device, wherein the first functional layer is a coating layer containing a hole injection material.
The optical device according to any one of claims 9 to 12,
The transflective layer is an optical device in which the high refractive index layer and the low refractive index layer are repeatedly positioned.
The optical device according to any one of claims 1 to 13,
The optical device in which the reflectance with respect to the peak wavelength of the emission spectrum of the light emitting unit is 30% or more.
15. The optical device according to claim 14, wherein
An optical device that satisfies the following formula (1), where L 1 is an optical film thickness of the optical layer, and λ is any wavelength included in the emission spectrum of the optical device.
0.9λ (2m−1) / 4 <L 1 <1.1λ (2m−1) / 4 (m is a positive integer) (1)
The optical device according to claim 15, wherein
When the optical thickness of the layer located between the second electrode and the semitransparent reflective layer has a L 2,
An optical device that satisfies the following formula (2).
m × 0.8 <2L / λ + φ / (2π) <m × 1.2 (2)
Where φ is a phase shift (in radians) in reflection, and n is 0 or a positive integer.
The optical device according to claim 15 or 16,
The λ is an optical device that is a peak wavelength of the radiation spectrum.