JP4686981B2 - Organic EL display device - Google Patents

Description

  The present invention relates to an organic EL display device having a mirror function utilizing reflection of a cathode in an organic EL (electroluminescence) element.

  2. Description of the Related Art Conventionally, a so-called rear mirror with a built-in monitor has been proposed in which a reflection surface of a rear mirror (back mirror) of an automobile is configured by a semi-transmissive mirror and a display device such as a liquid crystal monitor is disposed behind it.

  This displays various information through a semi-transmissive mirror by turning on a display device such as a liquid crystal monitor, and functions as a normal rearview mirror by turning off the display device such as a liquid crystal monitor. It is what I did.

  FIGS. 6A and 6B are diagrams showing a general conventional structure in a case where this type of monitor-equipped rear-view mirror is configured as an inner mirror J100 of an automobile, where FIG. 6A is a front view and FIG. 6B is a schematic cross-sectional view. .

  The inner mirror J100 includes a mirror housing 10, and a semi-transparent mirror J20 is fitted in the front opening 11 of the mirror housing 10. A plate-like spacer J30 is disposed behind the semi-transparent mirror J20 so as to be in contact with the semi-transparent mirror J20. The spacer J30 is, for example, black.

  An opening J31 is formed in a part of the spacer J30, and the screen J61 of the display J60 including a liquid crystal monitor or the like disposed behind the spacer J30 (a region indicated by a one-dot chain line in FIG. 6B). However, it faces the translucent mirror J20 through the opening J31 of the spacer J30. Here, for example, a TFT-LCD or the like is used as the liquid crystal monitor.

  According to the above configuration, as shown in FIG. 6A, the opening J31 of the spacer J30 is a display area where display is performed by the display device J60, and has a mirror function other than the display area J31. The region is a non-display mirror region 120, and here is a region where a spacer J30 is disposed behind.

  When the display device J60 such as a liquid crystal monitor is in an off state, the monitor built-in rear-view mirror J100 functions as a rear-view mirror on the entire surface of the semi-transparent mirror J20, and reflects the rear view image to the driver's eyes. To reach. That is, both the display area J31 and the non-display mirror area 120 function as a rearview mirror.

  On the other hand, when the display device J60 such as a liquid crystal monitor is turned on, an image is displayed on the screen J61. This image passes through the opening J31, passes through the semi-transmissive mirror J20, and reaches the eyes of the driver. At this time, the portion other than the screen J61, that is, the non-display mirror region 120 functions as a rearview mirror, and reflects the rear view image to reach the driver's eyes.

  Here, the monitor built-in rear-view mirror J100 shown in FIG. 6 has a non-display mirror region 120 with the spacer J30 behind and a screen J61 of the display J60 without the spacer J30 behind the driver. Since the gloss and color are different from the opening J31 as the display area and are clearly distinguished visually, there is a problem that when the display device J60 is turned off, a sense of incongruity is felt at the time of rearward viewing.

  In order to improve this problem, as shown in FIGS. 7A and 7B, a device provided with a blur part 130 has been proposed. 7A is a front view, and FIG. 7B is a schematic cross-sectional view. What is shown in FIG.

  This is because the black paint film J40 is formed on the part of the display device J60 excluding the screen J61, that is, on the mirror surface (inner surface) of the semi-transmissive mirror J20 in the non-display mirror region 120, and at the boundary with the screen J61 By providing the blur part 130 in which the density of the striped coating film surface is changed, the boundary between the screen J61 part and the non-display mirror region 120 is made inconspicuous.

  However, in the above method, since there is the blur part 130, there is a problem that the display content is difficult to see on the screen J61 in the vicinity of the blur part 130.

  Further, as is also the case shown in FIG. 6, a semi-transparent mirror J20 is disposed on the front surface of the screen J61. In order to ensure the visibility of various information, the display brightness of the display device J60 is displayed. Need to be high. Therefore, when a liquid crystal monitor is used as the display J60, there is a problem that the life of the light source is shortened.

  On the other hand, conventionally, an organic EL display device having a mirror function in which a mirror function is provided by utilizing reflection of a cathode in an organic EL element has been proposed (for example, see Patent Document 2).

  An organic EL element is formed by sandwiching an organic EL film between a positive electrode and a negative electrode on a transparent glass substrate. Since the cathode is made of aluminum or the like, in an organic EL display device having a mirror function, It is intended to function as a mirror when an organic EL element is not used by utilizing reflection such as aluminum.

However, in Patent Document 2, an organic EL element is formed on the entire surface of a mirror surface, that is, a glass substrate serving as a mirror, and a sealing structure for covering the organic EL element and protecting it from moisture or the like is a mirror surface. It is necessary for the entire surface, and becomes expensive in cost.
JP-A-7-267002 JP 2001-148290 A

  By the way, the present inventors are trying to develop an organic EL element, and developing an organic EL display device using a part of a semi-transparent mirror as a display area and using the organic EL element as a display arranged in the display area. Tried.

  FIGS. 8A and 8B are diagrams showing a schematic configuration of an organic EL display device J200 having a mirror function as an inner mirror, which was prototyped by the present inventors, and FIG. 8A is a front view. (B) is a schematic sectional drawing.

  In this organic EL display device J100, a semi-transmissive mirror J20 is fitted in the front opening 11 of the mirror housing 10, and a black plate-like spacer J30 is in contact with the semi-transmissive mirror J20 behind the semi-transmissive mirror J20. Is arranged in.

  An opening J31 formed in a part of the spacer J30 is formed, and the organic EL element 60 disposed behind the spacer J30 faces the transflective mirror J20 through the opening J31 of the spacer J30. Yes.

  In the above configuration, as shown in FIG. 8A, the opening J31 of the spacer J30 is a display area where display is performed by the organic EL element 60, and has a mirror function other than the display area J31. The region is a non-display mirror region 120, and here is a region where a spacer J30 is disposed behind.

  In the organic EL display device J200, the organic EL element 60 is turned on to display various information through the semi-transmissive mirror J20, and is turned off to function as a normal rearview mirror. Here, in the off state, the rear view image passes through the transparent anode and the organic EL film from the opening J31 of the spacer J30, is reflected by the cathode 50, and reaches the eyes of the driver. .

  However, in the case of this organic EL display device J200, according to the study by the present inventors, the visibility deteriorates as shown in FIG. FIG. 9 is a cross-sectional view schematically showing the cause of the visibility deterioration in the prototype.

  As shown in FIG. 9, the display image d emitted from the organic EL element 60 is reflected by the inner surface J22 of the semi-transmissive mirror J20, and the reflected image reflected on the inner surface J22 is reflected by the cathode 50 of the organic EL element 60. And projected as a virtual image d ′. Then, the display image looks double in the driver's eye K1, and visibility is deteriorated.

  As in the case of the monitor built-in rear-view mirror J100 shown in FIG. 6, the non-display mirror region 120 with the spacer J30 behind and the organic EL element 60 without the spacer J20 behind is viewed from the driver. Since the gloss and color are different from the opening J31 as a certain display area and are clearly distinguished visually, when the organic EL element 60 is turned off, a sense of incongruity is felt at the time of rearward viewing.

  The present invention has been made in view of the circumstances as described above, and in a display device that has a mirror function on the entire surface and uses a part as a display area, realizes an inexpensive configuration, a display area, and a non-display mirror. The object is to reduce the uncomfortable feeling at the boundary with the region.

In order to achieve the above object, in the invention described in claim 1, the reflection of the cathode (50) in the organic EL element (60) in which the organic EL film (40) is sandwiched between the anode (30) and the cathode (50). The organic EL film (40) has an organic layer (41) in which the wavelength dependence of the spectral transmittance is non-uniform in the organic EL display device having a mirror function utilizing the mirror. The organic EL film (40) is formed only in the display area (110) where the display is performed by the organic EL element (60) in the area having the function, and the display area (110) An organic layer (41) and a cathode (50) in which the wavelength dependence of the spectral transmittance is not uniform are laminated in the non-display mirror region (120) having a flat structure and a mirror function other than the above. Being formed It is characterized.

  According to this, the organic EL film (40) may be formed only in the display area (110) where the display is performed by the organic EL element (60) in the area having the mirror function, and in areas other than the display area (110). In the organic EL film (40), the organic layer (41) having a non-uniform wavelength dependency of spectral transmittance may be formed.

  Therefore, it can be set as a cheaper structure compared with the case where the organic EL film (40) is formed on the entire surface of the region having the mirror function.

  Further, since the cathode (50) itself functions as a mirror surface over the entire area having the mirror function, the sense of incongruity between the display area (110) and the non-display mirror area (120) is almost eliminated.

  Moreover, when the organic EL film (40) has an organic layer (41) in which the wavelength dependence of the spectral transmittance is not uniform, the transmittance of the organic layer (41) varies depending on the wavelength. It becomes a colored layer.

If divided into organic and EL film (40) was formed display region (110) and the cathode (50) non-display mirror region formed only (120), in both of these areas, since the color differences occur, these There may be a sense of discomfort at the boundary between the two regions.

  In such a case, as in the present invention, the organic layer (41) having the wavelength dependency of the spectral transmittance that causes the difference in color among the layers constituting the organic EL film (40) has a mirror function. By forming it over the entire area, the uncomfortable feeling at the boundary between the two areas is improved.

  Therefore, according to the present invention, in a display device that has a mirror function on the entire surface and uses a part as the display region (110), an inexpensive configuration is realized, and the display region (110) and the non-display mirror region (120) are provided. ) Can be reduced.

In the invention described in claim 2, in the organic EL display device according to claim 1, the organic layer wavelength dependence of the spectral transmittance is uneven (41), white light of the organic layer (41) Is transmitted, the color difference between the light after transmission and the light before transmission changes by 5 or more.

  This takes into account human visual characteristics. Generally, when the color difference changes by 5 or more, the difference in light color can be recognized in terms of human visual characteristics.

  Therefore, as in the present invention, the organic layer (41) in which the color difference changes by 5 or more is formed on the entire surface of the region having a mirror function, whereby the color difference between the display region (110) and the non-display mirror region (120). Can be made 5 or less, and the boundary is not recognized.

According to a third aspect of the present invention, in the organic EL display device according to the first aspect , the organic layer (41) in which the wavelength dependence of the spectral transmittance is not uniform is the smallest of the spectral transmittance in the visible light region. The value is 90% or less of the maximum value.

  The present invention also considers human visual characteristics. According to the study by the present inventors, when the minimum value of the spectral transmittance in the visible light region is 90% or less of the maximum value, the color difference between the light after transmission and the light before transmission increases to 5 or more. .

  Therefore, the display region (110) and the non-display mirror are formed by forming the organic layer (41) having the minimum value of 90% or less of the maximum value of the spectral transmittance in the visible light region on the entire surface having the mirror function. The color difference from the region (120) can be 5 or less, and the boundary is not recognized.

Here, as in the invention according to claim 4, in the organic EL display device according to claims 1 to 3, the organic layer wavelength dependence of the spectral transmittance is uneven and (41) The organic EL film (40) can be a hole injection layer (41).

It is preferable as defined in claim 5, in the organic EL display device according to claims 1 to 4, the organic layer wavelength dependence of the spectral transmittance is uneven and (41), Can be copper phthalocyanine.

Moreover, in invention of Claim 6, in the organic EL display device of Claims 1-5, only the organic EL element (60) formed in the display area (110) is a sealing member (70). The sealing member (70) is connected to the display region (110) at the periphery thereof, and the portion to which the sealing member is connected is connected to the cathode (50) and the organic material. It is characterized by the presence of the layer (41) .

  Usually, since an organic EL element is sensitive to moisture, a sealing structure such as a can seal is provided so as to cover the organic EL film so as to protect the organic EL film from moisture.

  In the present invention, since the organic EL film (40) is formed only in a necessary portion to be displayed, the sealing structure is only in this range, and the sealing structure is provided over the entire area having the mirror function. Will also be cheaper.

  In addition, the code | symbol in the bracket | parenthesis of each said means is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings and the above-described drawings, the same or equivalent parts are denoted by the same reference numerals in the drawings.

  FIG. 1 is a diagram showing a schematic configuration of an organic EL display device 100 having a mirror function as an inner mirror according to an embodiment of the present invention, where (a) is a front view and (b) is A in (a). It is a schematic sectional drawing in alignment with -A.

  The organic EL display device 100 includes a mirror housing 10, and a transparent glass substrate 20 is fitted in the front opening 11 of the mirror housing 10. The glass substrate 10 is divided into the outer shape of the inner mirror, and the entire surface exposed from the front opening 11 of the glass substrate 20 is configured as a region having a mirror function.

  An anode 30 as a transparent electrode is formed at a position corresponding to the display area 110 on the back surface of the transparent glass substrate 20. The anode 30 is made of a transparent conductive film made of, for example, ITO (indium tin oxide).

  A hole injection layer 41 made of a hole injection material is formed on the back surface of the anode 30. In this example, the hole injection layer 41 is made of copper phthalocyanine (CuPc), and exhibits a spectral transmittance characteristic as shown in FIG. 2 and is colored light blue.

When the hole injection layer 41 of this example is formed only in the display region 110 in alignment with the anode 30, when 100 cd / m ² of white light is transmitted, the color difference between the light after transmission and the light before transmission is 46. .4 greatly changes, and a difference in appearance occurs at the boundary between the display area 110 and the non-display mirror area 120 having a mirror function other than the display area 110, resulting in poor visibility. Generally, when the color difference changes by 5 or more, the difference in light color can be recognized in terms of human visual characteristics.

  Therefore, in this embodiment, as shown in FIG. 1, in order to eliminate the color difference, the hole injection layer 41, which is an organic layer in which the color difference changes by 5 or more, is formed on the entire surface of the region having the mirror function. ing. Thereby, the color difference between the display area 110 and the non-display mirror area 120 can be made 5 or less, and the boundary is not recognized.

  In addition, a hole transport layer 42, a light emitting layer 43, an electron transport layer 44, and an electron injection layer 45 are sequentially formed at a position corresponding to the display region 110 on the back surface of the hole injection layer 41. These hole transport layer 42, light emitting layer 43, electron transport layer 44, and electron injection layer 45 are usually formed by vapor deposition using materials that can be employed in organic EL elements.

  That is, in the organic EL display device 100, the organic EL film 40 in which the hole injection layer 41, the hole transport layer 42, the light emitting layer 43, the electron transport layer 44, and the electron injection layer 45 are laminated only on the display region 110. Is formed.

  Although not limited here, for example, a hole transporting material such as a triphenylamine tetramer can be adopted as the hole transport layer 42, and a triphenylamine tetramer or adamantane can be used as the light emitting layer 43. A host material made of a derivative or the like and a dopant material as a fluorescent dye such as rubrene or perylene can be used.

  As the electron transport layer 44, an electron transport material such as aluminum quinolate (Alq3) can be employed. The electron injection layer 45 is often made of lithium fluoride and is not an organic layer, but is included in the organic EL film 40 here.

  Here, when the hole transport layer 42 excluding the hole injection layer 41, the light emitting layer 43, the electron transport layer 44, and the electron injection layer 45 are partially formed by vapor deposition, only necessary portions are usually used using a mask or the like. An organic layer is formed on the mask, but the organic layer is formed on the mask in the unnecessary portion, so that the material cost cannot be reduced.

  In this embodiment, in a process that requires partial film formation, as shown in FIG. 3, the glass substrate 20 and the mask are arranged in multiple stages in a positional relationship such that the other glass substrate 20 does not overlap the region where film formation is desired. M1 is disposed to form a film. As a result, the same effect as that of multi-cavity can be obtained, the utilization efficiency of the film forming material can be improved, and the cost can be reduced.

  In addition, when the hole transport layer 42, the light emitting layer 43, the electron transport layer 44, and the electron injection layer 45 are partially formed by vapor deposition, a mask used for vapor deposition is used separately for each layer. The organic material attached to the mask after the film may be scraped and reused.

  Further, in the organic EL display device 100 shown in FIG. 1, a cathode 50 made of aluminum or the like is formed on the back surface of the electron injection layer 45. Since the cathode 50 also has a function as a mirror surface of the inner mirror in the organic EL display device 100, the cathode 50 is formed on the entire surface of the glass substrate 1 having a mirror function.

  As described above, the organic EL element 60 in which the organic EL film 40 is sandwiched between the anode 30 and the cathode 50 is formed in the display region 110. As shown in FIG. 1, a sealing can 70 is provided on the back surface of the cathode 50 so as to cover only the organic EL element 60.

  The sealing can 70 is made of resin, glass, metal or the like and is fixed by adhesion or the like, and is configured as a sealing member for sealing the organic EL film 40 in the organic EL element 60 to protect it from the outside air. It has been done.

  In such an organic EL display device 100 as an organic EL integrated inner mirror, the display area 110 includes a vehicle periphery image detected by a camera mounted on the vehicle and various vehicle information by the organic EL element 60. Is displayed. The display is turned on / off by, for example, a driver's switch operation.

  Hereinafter, the operation of the organic EL display device 100 will be described. When the display of the display area 110 of the organic EL display device 100 is in an off state (non-display state), the entire surface of the cathode 50 functions as a rearview mirror, and reflects the rear view image to reach the driver's eyes.

  On the other hand, when the display of the display area 110 of the organic EL display device 100 is turned on (display state), an image is displayed in the display area 110, and this image passes through the glass substrate 20 and reaches the eyes of the driver. . At this time, the non-display mirror region 120 other than the display region 110 functions as a rearview mirror, and reflects the rear view image.

By the way, according to the present embodiment, the organic EL display device 100 is provided with a mirror function by utilizing the reflection of the cathode 50 in the organic EL element 60 in which the organic EL film 40 is sandwiched between the anode 30 and the cathode 50. The organic EL film 40 is formed only in the display area 110 where the display is performed by the organic EL element 60 in the area having the mirror function, and the display element 110 has a mirror structure other than the display area 110. An organic EL display device 100 is provided in which a cathode 50 is formed in the non-display mirror region 120 to be provided.

  According to this, the organic EL film 40 may be formed only in the display area 110 where the display is performed by the organic EL element 60 in the area having the mirror function, and the organic EL film 40 is formed in an area other than the display area 110. It does not have to be.

  Therefore, by adopting the film forming method described with reference to FIG. 3 and the like, it is possible to make the structure cheaper than when the organic EL film 40 is formed on the entire surface of the region having the mirror function.

  In addition, since the cathode 50 itself functions as a mirror surface over the entire area having the mirror function, there is almost no sense of incongruity at the boundary between the display area 110 and the non-display mirror area 120.

  Therefore, according to the organic EL display device 100 of the present embodiment, an inexpensive configuration is realized in the display device having a mirror function on the entire surface and a part of the display device as the display region 110, and the display region 110 and the non-display mirror are realized. The uncomfortable feeling at the boundary with the region 120 can be reduced.

  In the example shown in FIG. 1 described above, in the organic EL display device 100, the organic EL film 40 includes a hole injection layer 41 made of copper phthalocyanine as an organic layer in which the wavelength dependency of spectral transmittance is not uniform. Have.

  In this case, in this example, the organic EL film 40 is formed only in the display area 110 where the display is performed by the organic EL element 60 in the area having the mirror function, and the display has an element configuration. The non-display mirror region 120 having a mirror function other than the region 110 is formed by laminating a hole injection layer 41 and a cathode 50 as an organic layer in which the wavelength dependence of spectral transmittance is not uniform. .

  According to the example shown in FIG. 1, the organic EL film 40 may be formed only in the display region 110, and the wavelength dependence of the spectral transmittance of the organic EL film 40 is not present in regions other than the display region 110. Only the uniform organic layer 41 may be formed, and the other hole transport layer 42, light emitting layer 43, electron transport layer 44, and electron injection layer 45 may not be formed.

  Therefore, by adopting the film forming method described with reference to FIG. 3 and the like, it is possible to make the structure cheaper than when the organic EL film 40 is formed on the entire surface of the region having the mirror function.

  In the example shown in FIG. 1 as well, as described above, the cathode 50 itself functions as a mirror surface over the entire area having the mirror function, so that the border between the display area 110 and the non-display mirror area 120 is almost uncomfortable. Disappear.

  In this example, the organic EL film 40 has a hole injection layer 41 made of copper phthalocyanine as an organic layer in which the wavelength dependence of the spectral transmittance is not uniform. As described above, the transmittance has wavelength dependency (see FIG. 2 above) and is a light blue layer.

  In that case, when divided into the display area 110 in which the organic EL film 40 is formed and the non-display mirror area 120 in which only the cathode 50 is formed, a color difference occurs between these two areas.

  For example, as described above, in the case of the hole injection layer 41 made of copper phthalocyanine, the color difference between the display region 110 and the non-display mirror region 120 is greatly changed to 46.4, and a sense of incongruity is generated at the boundary between these two regions.

  In such a case, as in this example, the hole injection layer 41 having the wavelength dependency of the spectral transmittance that causes the color difference among the layers constituting the organic EL film 40 is formed in a region having a mirror function. By forming it on the entire surface, the uncomfortable feeling at the boundary between the two regions is improved.

  That is, even with the organic EL display device configured as in this example shown in FIG. 1, an inexpensive configuration can be realized, and the uncomfortable feeling at the boundary between the display area 110 and the non-display mirror area 120 can be reduced. .

  More specifically, in this example, layers other than the cathode 50 used as a mirror surface and the hole injection layer 41 colored in light blue, that is, the anode 30, the hole transport layer 42, the light emitting layer 43, and the electron transport layer. 44. Since the electron injection layer 45 is colorless and transparent, even when the display of the organic EL display device 100 is turned off, the boundary of the display area 110 is not seen, and a sense of incongruity is not felt at the time of rearward viewing.

  In the present embodiment, when there is no organic layer having a wavelength dependency of spectral transmittance that causes a color difference among the layers constituting the organic EL film 40, the non-display mirror region 120 includes Only the cathode 50 may be formed without forming the hole injection layer 41. The effect in that case is as described above.

  Here, the organic layer in which the wavelength dependency of the spectral transmittance is not uniform in the organic EL film 40 may be other than the hole injection layer 41 made of copper phthalocyanine.

  Specifically, when white light is transmitted through the organic layer, any color difference between the light after transmission and the light before transmission may change by 5 or more. Of course, the hole injection layer 41 made of copper phthalocyanine is also such.

  This configuration relating to the color difference takes into consideration human visual characteristics. Generally, when the color difference changes by 5 or more, the difference in light color can be recognized in terms of human visual characteristics.

  Therefore, the color difference between the display area 110 and the non-display mirror area 120 can be made 5 or less by forming the organic layer 41 whose color difference changes by 5 or more on the entire surface of the area having the mirror function, and the boundary is It will not be recognized.

  Furthermore, the organic layer 41 in which the wavelength dependence of the spectral transmittance is nonuniform in the organic EL film 40 is a layer having a minimum value of 90% or less of the maximum value of the spectral transmittance in the visible light region. Good. Of course, the hole injection layer 41 made of copper phthalocyanine is also such.

  The configuration relating to the minimum value and the maximum value of the spectral transmittance also considers human visual characteristics. According to the study by the present inventors, when the minimum value of the spectral transmittance in the visible light region is 90% or less of the maximum value, the color difference between the light after transmission and the light before transmission increases to 5 or more. .

  The inventors investigated the relationship between spectral transmittance and color difference by simulation. Although not limited, an example is shown in FIGS.

  FIG. 4 is a diagram illustrating an example of the case where the wavelength dependence of the spectral transmittance in the visible light region is uniform and a case where it partially changes. In FIG. 4, the spectral transmittance is uniform with 1 in the entire visible light region, and 0.9, 0.8, 0.7,... Gradually lower only in the region of 580 nm to 780 nm. Is shown.

  That is, in FIG. 4, when the values of 0.9, 0.8, 0.7,... Are gradually lowered only in the latter 580 nm to 780 nm region, the minimum value of the spectral transmittance in the visible light region is This corresponds to a case where the maximum value is 90%, 80%, or 70%.

  FIG. 5 is a diagram showing the results obtained by calculating the relationship between the spectral transmittance in the region of 580 nm to 780 nm shown in FIG. 4 and the color difference between the light after transmission and the light before transmission. . As shown in FIG. 5, it was found that the spectral transmittance in the region of 580 nm to 780 nm needs to be 90% or more in order to make the above color difference within 5.

  Therefore, the organic layer 41 having a minimum value of 90% or less of the spectral transmittance in the visible light region is formed on the entire surface of the region having the mirror function, so that the display region 110 and the non-display mirror region 120 are formed. The color difference can be made 5 or less, and the boundary is not recognized.

  Further, the organic EL display device 100 according to the present embodiment is characterized in that only the organic EL element 60 formed in the display region 110 is sealed and protected by the sealing member 70.

  Usually, since an organic EL element is sensitive to moisture, a sealing structure such as a can seal is provided so as to cover the organic EL film so as to protect the organic EL film from moisture.

  In this embodiment, since the organic EL film 40 is formed only in a necessary portion to be displayed, the sealing structure is only in this range, and compared with the case where the sealing structure is provided over the entire area having the mirror function. It will be cheaper.

  Further, as shown in FIG. 1, in the organic EL display device 100, the non-display mirror region 120 can be made wider than the display region 110.

  In addition, since the organic EL display device 100 according to the present embodiment uses the mirror reflection of the cathode 50, the expensive circularly polarizing plate used for preventing the reflection of the cathode, which has been a problem in the past, is unnecessary. .

  Since the transmittance is improved by omitting the circularly polarizing plate, the display luminance of the organic EL element 60 can be lowered, and the lifetime of the element is improved. At the same time, significant cost reductions can be expected by reducing parts.

  In addition, as described above, in the conventional rear-view mirror using the semi-transmission mirror (see FIGS. 6 and 7 above), the semi-transmission mirror is disposed on the front surface of the screen to increase the display brightness of the display. Therefore, when a liquid crystal monitor is used as a display, there is a problem that the life of the light source is shortened.

  On the other hand, in the organic EL display device 100 of the present embodiment, light emitted from the organic EL film 40 of the organic EL element 60 is extracted through the transparent anode 30 and the glass substrate 20. For this reason, the display luminance can be lowered as compared with the case where a semi-transparent mirror is used, and the device life can be improved.

  In addition, the example of the film forming method described with reference to FIG. 3 and the like is an example of forming a low molecular organic EL film by vapor deposition, but the high molecular organic EL may be formed by an ink jet method. .

  In that case, it is the same by forming the polymer organic EL layer in the range necessary for display by the vapor deposition or the ink jet method using the material used only in the range that requires the entire film formation, and forming the same range by the ink jet method. Cost reduction is possible.

(Other embodiments)
In addition, as the anode 30, the organic EL film 40, and the cathode 50 of the organic EL element 60, if the anode has a transparent electrode and the cathode has a mirror function, a material that can be used for a normal organic EL element is appropriately adopted. Can do.

  Needless to say, the organic EL display device shown in the above embodiment is not limited to the inner mirror (rear mirror) of the vehicle.

  In short, the present invention includes the organic EL element 60 in which the organic EL film 40 is sandwiched between the anode 30 and the cathode 50, and the portion where the cathode 50 of the organic EL element 60 is formed on the transparent glass substrate 20 has a mirror function. Any organic EL display device having a region (mirror surface) can be applied.

  In such an organic EL display device, the organic EL film 60 is formed only in the display area 110 on the mirror surface to form an element that can be displayed, and in the mirror surface other than the display area 110, The cathode 50 is formed, and the design can be changed as appropriate in addition to the above embodiments.

It is a figure which shows schematic structure of the organic electroluminescence display which concerns on embodiment of this invention, (a) is a front view, (b) is an AA schematic sectional drawing in (a). It is a figure which shows the spectral transmittance characteristic of copper phthalocyanine. It is a schematic sectional drawing which shows the partial film-forming method of the organic EL film concerning the said embodiment. It is a figure which shows an example when the wavelength dependence of the spectral transmittance in a visible light area | region is uniform, and changes partially. It is a figure which shows the relationship between the spectral transmittance of the 580 nm-780 nm area | region shown by the said FIG. 4, and the color difference of the light after transmission, and the light before transmission. It is a figure which shows the general conventional structure of a rear-view mirror with a built-in monitor, (a) is a front view, (b) is a schematic sectional drawing. It is a figure which shows the conventional structure of the rear-view mirror with a built-in monitor which provided the blurring part in the boundary of a monitor screen part and a non-display mirror area | region, (a) is a front view, (b) is a schematic sectional drawing. BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram of the organic electroluminescent display apparatus provided with the mirror function which the present inventors made as an experiment, (a) is a front view, (b) is a schematic sectional drawing. It is a figure which shows the cause of the visibility deterioration in the prototype shown by the said FIG.

Explanation of symbols

30 ... Anode, 40 ... Organic EL film, 41 ... Hole injection layer, 42 ... Hole transport layer,
43 ... Light-emitting layer, 44 ... Electron transport layer, 45 ... Electron injection layer, 50 ... Cathode,
60 ... Organic EL element, 70 ... Sealing can as sealing member, 110 ... Display area,
120 ... non-display mirror region.

Claims (6)

Organic EL display having a mirror function by utilizing the reflection of the cathode (50) in the organic EL element (60) in which the organic EL film (40) is sandwiched between the anode (30) and the cathode (50). In the device
The organic EL film (40) has an organic layer (41) in which the wavelength dependence of spectral transmittance is non-uniform,
In the region having a mirror function, the organic EL film (40) is formed only in the display region (110) where the display is performed by the organic EL device (60), and the device configuration is capable of displaying.
In the non-display mirror region (120) having a mirror function other than the display region (110) and having a flat structure , the organic layer (41) and the cathode in which the wavelength dependence of the spectral transmittance is not uniform. (50) is laminated | stacked and formed, The organic electroluminescence display characterized by the above-mentioned. The organic layer (41) in which the wavelength dependence of the spectral transmittance is not uniform means that when white light is transmitted through the organic layer (41), the color difference between the light after transmission and the light before transmission is 5 The organic EL display device according to claim 1 , wherein the organic EL display device changes as described above. The organic layer (41) in which the wavelength dependence of the spectral transmittance is non-uniform is characterized in that the minimum value of the spectral transmittance in the visible light region is 90% or less of the maximum value. Item 2. An organic EL display device according to Item 1 . Wherein the organic layer wavelength dependence of the spectral transmittance is uneven (41), claims 1, wherein the a positive hole injection layer of the organic EL layer (40) (41) 3 The organic EL display device according to any one of the above. The organic EL display device according to any one of claims 1 to 4 , wherein the organic layer (41) in which the wavelength dependence of the spectral transmittance is non-uniform is copper phthalocyanine. Only the organic EL element (60) formed in the display region (110) is sealed by the sealing member (70) ,
The sealing member (70) has a peripheral portion connected to the display area (110), and the portion to which the sealing member is connected includes the cathode (50) and the organic layer (41). the organic EL display device according to any one of claims 1 to 5, characterized in that there exists.

Images