Electronic device

Abstract

Provided is an electronic device having little stray light. An electronic device includes a display panel and an optical device having a function of partially reducing brightness of light emitted by the display panel. A half mirror or a dimming filter or the like, the transmittance of which is continuously reduced from the inside to the outside, can be used in an optical device. By using this structure, stray light that is likely to occur at the periphery of the lens can be suppressed, and thus visibility of an image displayed on the display panel can be improved.

Description

Technical Field

[0001] One embodiment of the present invention relates to an electronic device including an optical device.

[0002] Note that one embodiment of the present invention is not limited to the above-mentioned technical field. The technical field of one embodiment of the invention disclosed in this specification, etc., relates to an object, method or manufacturing method. In addition, one embodiment of the present invention relates to a process, a machine, a product or a composition of matter. Therefore, more specifically, as an example of the technical field of one embodiment of the present invention disclosed in this specification, a semiconductor device, a display device, a liquid crystal display device, a light-emitting device, a lighting device, a power storage device, a storage device, a camera device, a method for operating these devices or a method for manufacturing these devices can be cited.

[0003] Note that in this specification and the like, a semiconductor device refers to any device that can operate by utilizing semiconductor characteristics. A transistor and a semiconductor circuit are one form of a semiconductor device. In addition, a storage device, a display device, a camera device, and an electronic device may include a semiconductor device. Background Art

[0004] As electronic devices applied to virtual reality (VR) or augmented reality (AR), goggles-type devices and glasses-type devices have been developed.

[0005] In addition, as a display device that can be applied to the display panel, a display device including a liquid crystal element, a display device including an organic EL (Electro Luminescence) element or a light emitting diode (LED: Light Emitting Diode), etc. can be typically mentioned.

[0006] Since a display device including an organic EL element does not require a backlight source required for a liquid crystal display device, a thin, lightweight, high-contrast, and low-power display device can be realized. For example, Patent Document 1 discloses an example of a display device using an organic EL element. [Prior technical literature] [Patent Document]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 2018-107444 Summary of the invention Technical problem to be solved by the invention

[0008] Electronic devices used in VR and AR are one type of wearable devices, and need to be small in order to improve portability and wearability. Therefore, optical devices designed to reduce the focal distance are used in such electronic devices.

[0009] This optical device has a structure that ensures the optical path length by using polarization and reflection between components, and sometimes produces unintentional surface reflection light and polarization state destruction light caused by optical components. These lights are incident on the eyes away from the normal optical path and are seen as stray light. Stray light is one of the reasons for reducing the quality of the image being seen.

[0010] Therefore, one of the purposes of one embodiment of the present invention is to provide an electronic device with less stray light. In addition, one of the purposes of one embodiment of the present invention is to provide an electronic device with high image quality. In addition, one of the purposes of one embodiment of the present invention is to provide a small and thin electronic device. In addition, one of the purposes of one embodiment of the present invention is to provide a novel electronic device.

[0011] Note that the description of these purposes does not prevent the existence of other purposes. Note that one embodiment of the present invention does not necessarily achieve all of the above purposes. Note that purposes other than the above can be known and extracted from the description of the specification, drawings, claims, etc. Solutions to technical problems

[0012] One embodiment of the present invention relates to an electronic device with less stray light.

[0013] One embodiment of the present invention is an electronic device comprising a display panel and an optical device, wherein the optical device has a first function of gathering light emitted by the display panel and emitting it to the eyes of a user and a second function of partially reducing the brightness of the light emitted by the display panel, and an image can be seen by continuously increasing the brightness reduction rate of the light emitted by the display panel from the central area of ​​the field of view to the edge of the field of view.

[0014] The optical device may include a half mirror having a region where transmittance continuously decreases from the inside toward the outside.

[0015] Furthermore, the optical device may include a neutral density filter having a region in which transmittance continuously decreases from the inside toward the outside.

[0016] The central area is preferably within a range of 20° to 40°, including the center of the field of view.

[0017] When the transmittance of the optical device corresponding to the central area is 1, the transmittance of the optical device corresponding to the edge of the field of view is preferably 0.3 or more and 0.7 or less.

[0018] The display panel preferably includes an organic EL element. Effects of the Invention

[0019] According to one embodiment of the present invention, an electronic device with less stray light can be provided. In addition, an electronic device with high image quality can be provided. In addition, a thin and light electronic device can be provided. In addition, a novel electronic device can be provided.

[0020] Note that the description of these effects does not prevent the existence of other effects. One embodiment of the present invention does not necessarily have all of the above effects. Effects other than the above effects can be extracted from the description of the specification, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1A and Figure 1B A diagram for explaining a state in which an image displayed on a display panel is viewed through an optical device. Figure 2 This is a diagram to illustrate the viewing angle. Figure 3 This is a diagram illustrating the transmittance of an optical device. Figure 4A and Figure 4B It is a diagram for explaining an optical device. Figure 5A and Figure 5B It is a diagram for explaining an optical device. Fig. 6A This is a diagram for explaining a half mirror. Figure 6B It is a diagram for explaining a neutral density filter. Fig. 7A and Figure 7B It is a diagram for explaining an optical device. Figure 8 It is a diagram for explaining an electronic device. 9A to 9C It is a diagram for explaining a display device. Fig. 10A and Fig. 10B It is a diagram for explaining a glasses-type device. FIG. 11A to FIG. 11C A diagram illustrating a structural example of a display panel. Fig. 12A and Fig. 12B A diagram illustrating a structural example of a display panel. FIG. 13A to FIG. 13F A diagram illustrating an example of the structure of a pixel. Fig.14A and Fig. 14B A diagram illustrating a structural example of a display panel. Fig.15 A diagram illustrating a structural example of a display panel. Fig.16 A diagram illustrating a structural example of a display panel. Fig.17 A diagram illustrating a structural example of a display panel. Fig.18 A diagram illustrating a structural example of a display panel. Fig.19 A diagram illustrating a structural example of a display panel. Fig. 20 A diagram illustrating a structural example of a display panel. Fig.21 A diagram illustrating a structural example of a display panel. Modes for Carrying Out the Invention

[0022] The embodiments are described in detail with reference to the accompanying drawings. Note that the present invention is not limited to the following description, and a person of ordinary skill in the art can easily understand the fact that its methods and details can be transformed into various forms without departing from the purpose and scope of the present invention. Therefore, the present invention should not be interpreted as being limited to the contents described in the embodiments shown below. Note that in the structure of the invention described below, the same figure marks are used in different drawings to represent the same parts or parts with the same functions, and their repeated descriptions are omitted. Note that the shading of the same constituent elements is sometimes appropriately omitted or changed in different drawings.

[0023] In addition, even if there is one element in the circuit diagram, the element may be composed of multiple elements if there is no problem in terms of function. For example, sometimes multiple transistors used as switches may be connected in series or in parallel. Also, sometimes a capacitor is divided and arranged in multiple locations.

[0024] In addition, sometimes a conductor has multiple functions such as wiring, electrode and terminal, and in this specification, multiple names are sometimes used for the same element. In addition, even if the circuit diagram shows that the elements are directly connected, sometimes the elements are actually connected through more than one conductor, and this structure is also included in the category of direct connection in this specification.

[0025] (Implementation Method 1) In this embodiment, an electronic device which is one embodiment of the present invention is described.

[0026] One embodiment of the present invention is an electronic device such as a goggle-type device or a glasses-type device, including a display panel and an optical device. The optical device has a function of collecting light emitted by the display panel and emitting it to the user's eyes. In addition, the optical device has a function of partially reducing the brightness of the light emitted by the display panel, thereby reducing stray light.

[0027] Stray light is light that is incident on the eye away from the normal optical path and is seen as superimposed on the regular image. Stray light is a cause of degrading the quality of displays seen with electronic devices. Because stray light appears in unintended locations, it is sometimes called ghosting.

[0028] A half mirror or a neutral density filter whose transmittance decreases continuously from the inside to the outside can be used in an optical device. By using such a member, stray light that is easily generated in the periphery of the lens can be suppressed, thereby improving the visibility of the image displayed on the display panel.

[0029] Note that the optical device included in the electronic device of one embodiment of the present invention has a structure of combining a plurality of optical components. The object containing this structure in a frame is simply called a lens. Alternatively, it is sometimes called a pancake lens because of its thin shape.

[0030] Figure 1A and Figure 1B 1 is a diagram illustrating a state where an image displayed on a display panel is seen through an optical device. Here, the dotted line surrounding the image indicates the edge of the field of view. Note that in this embodiment, the field of view of one eye corresponding to one display panel is used for description. In addition, the actual field of view is different between the horizontal direction and the vertical direction and its shape is unclear, but here the field of view is assumed to be a circular shape for description.

[0031] Figure 1A The image displayed by the display panel is magnified using an optical device that easily generates stray light. The stray light causes the quality of the visible state to be degraded, such as the image having double images, blurred outlines, or the stray light appearing as bright spots.

[0032] Stray light is more likely to be seen in the periphery of the field of view than in the center of the field of view. This phenomenon is caused by the use of polarization and the curvature of the lens. Small goggle-type devices and the like use structures that can use selective reflection of polarization in order to shorten the focal distance. Polarization passes through the lens in the normal light path and is reflected by a reflective polarizer. However, the incident angle of light becomes larger in the peripheral part of the lens, so the polarization state is sometimes destroyed. Part of this polarization is not reflected by the reflective polarizer and moves away from the normal light path, thus becoming stray light.

[0033] Figure 1B An optical device showing one way of using the present invention to see Figure 1AThe same image state. An optical device of one embodiment of the present invention has a function of partially reducing the brightness of light emitted by a display panel in an optical path. Specifically, it has the following effects: the brightness is reduced in a central area including the center of the field of view, and the brightness is continuously reduced from the edge of the central area to the edge of the field of view. In other words, it can be said that the brightness reduction rate of light emitted by the display panel is continuously increased from the edge of the central area to the edge of the field of view.

[0034] Figure 1B The following is shown: the brightness of the light emitted by the display panel is not reduced in the central area and the brightness of the light emitted by the display panel is continuously reduced from the edge of the central area to the edge of the field of view as if a gradient filter is used for dimming. As described above, stray light is easily generated in the peripheral part of the lens in the optical device, but by reducing the brightness of the periphery of the field of view corresponding to the peripheral part of the lens, the absolute amount of stray light generated can be reduced. In addition, in an optical device of one embodiment of the present invention described later, the ratio of stray light to light passing through the normal optical path can be reduced.

[0035] Here, we will explain the visibility when the brightness of the periphery of the visual field is reduced. The fovea and its vicinity on the retina of the human eye have high visual resolution, while the visual resolution of the area farther from the fovea on the retina is not as high as that of the fovea. Using this characteristic of the human eye, a foveated rendering technology is proposed, which tracks the user's line of sight when displaying images, displays the central field of view at high resolution, and displays the peripheral field of view at low resolution.

[0036] In a static state, the brightness is the same, and the central field of vision of the human eye is highly sensitive and the peripheral field of vision is less sensitive. That is, as in one embodiment of the present invention, even if the brightness is gradually reduced toward the edge of the field of vision, it is not easy for people to notice, so it does not feel unnatural. However, when the brightness is reduced excessively, people feel that the viewing angle is very narrow. Therefore, there is an appropriate range for adjusting the brightness in the peripheral field of vision.

[0037] Figure 2 θ is a diagram for explaining the viewing angle. When the edge of the visual field A of the electronic device of one embodiment of the present invention (one of the points constituting the periphery of the visual field A) is A1 and the edge of the visual field A opposite to A1 is A2, the angle formed by the straight line connecting the human eye 10 and A1 and the straight line connecting the human eye 10 and A2 is θ F θ F In addition, when the edge of the central area B (one of the points constituting the periphery of the central area B) is B1 and the edge of the central area B opposite to B1 is B2, the angle formed by the straight line connecting the human eye 10 and B1 and the straight line connecting the human eye 10 and B2 is θ C θ CIt is an angle that defines the central area B that overlaps with the central visual field. The central area B is preferably the same as or larger than the central visual field.

[0038] Viewing angle θ F It is an inherent value of electronic devices or human eyes. It has been confirmed through sensory testing that: regardless of the viewing angle θ F The size of the central area B specifies the angle θ C The angle is preferably 20° or more and 40° or less, more preferably 25° or more and 35° or less, and typically 30° is preferred.

[0039] Figure 3 Here, according to the above description, the angle θ of the central area B is defined as C For example, it can be set to 20°≤θ C ≤40°. This range includes the area overlapping with the central visual field and is an area where the sensitivity of the human eye is high, so the brightness reduction rate of the displayed image is preferably set to a value as small as possible. That is, the area corresponding to the central area B of the optical device has a structure in which no element for dimming is used to enter the optical path so that the transmittance is relatively high.

[0040] In addition, since polarization and a half mirror are used as optical devices, the transmittance may drop to about 10% even if the light reduction element does not enter the optical path. The transmittance of optical devices varies depending on the structure, and here, the relative transmittance when the transmittance in the center area B is 1 is explained.

[0041] From the edge of the central area B to the edge of the field of view A, the brightness reduction rate of the displayed image is continuously increased. In other words, the transmittance of the optical device is continuously reduced. Figure 3 In FIG. 1 , an appropriate transmittance range T1 obtainable from edge A1 of field of view A at the shortest distance from edge B1 of center region B and an appropriate transmittance range T2 obtainable from edge A2 of field of view A at the shortest distance from edge B2 of center region B are indicated by oblique lines.

[0042] like Figure 3 As shown, it is preferred that at 20°≤θ C When the transmittance of the edges B1 and B2 of the center area B is 1 when the transmittance is ≤40°, the transmittance is continuously reduced so that the transmittance of the edges A1 and A2 of the field of view A is 0.3 or more and 0.7 or less. This range is set based on the results of sensory tests. Outside this range, users feel that stray light is not sufficiently reduced, the viewing angle is very narrow, or the brightness of the displayed display is unnatural. Typically, at θ C =30°, preferably from θ C to θ F The transmittance decreases continuously and the transmittance at the edges A1 and A2 of the field of view A is 0.5.

[0043] In addition, since the normal optical path of the optical device includes the transmission path and the reflection path of the half mirror, the reduction of the transmittance between B1-A1 and B2-A2 is likely to be nonlinear (curve of a quadratic function), but it can also be linear. In addition, it is not limited to continuous change, and the transmittance can also be changed in stages in a way that has no effect when viewed.

[0044] Next, an optical device having a function of continuously increasing the brightness reduction rate of light emitted by a display panel is described. Here, the components having this function are described, and the overall structure and polarization state of the optical device are described in detail later. In addition, the transmission and reflection of incident light in a normal optical path and the generation of stray light are described, while reflection, transmission, and absorption other than the main functions of each component are ignored.

[0045] Figure 4A It is a comparative example of an optical device that does not reduce the brightness of a part, etc., and is also a cross-sectional view of a part of the components of an optical device that is easy to see stray light. The optical device includes a half mirror 41, a lens 42, a phase difference plate 43, a reflective polarizer 44, and a lens 45. Note that an example is shown in which the half mirror 41 is set on one surface of the lens 42, but it can also be set on a support different from the lens 42.

[0046] The incident light passes through the half mirror 41 and the lens 42, and is reflected by the reflective polarizer 44. At this time, due to the destruction of the polarization state caused by the lens 42, part of the light passes through the reflective polarizer 44 and the lens 45, and becomes stray light.

[0047] The amount of stray light I generated near the center of the optical device (near the central field of view) G The product of the incident light quantity I0 and the transmittance T of the half mirror and the ratio X of the light transmitted through the reflective polarizer (I G =I0·T·X(Formula 1)).

[0048] When the X value at the periphery of the lens 42 is a times higher than that near the center (a>1), the amount of stray light I′ generated at the periphery of the lens is G The product of the incident light quantity I0 and the transmittance T of the half mirror and the ratio aX of the light transmitted through the reflective polarizer (I' G =I0·T·aX(Formula 2)).

[0049] The light that has passed through the normal optical path and is reflected by the reflective polarizing plate 44 is reflected by the half mirror 41 and has its polarization converted, and then passes through the reflective polarizing plate 44 and the lens 45 .

[0050] Near the center of the optical device, the amount of light I (the amount of light in the normal optical path) transmitted through the reflective polarizer 44 is the product of the incident light amount I0, the transmittance T of the half mirror, and the reflectance (1-T) of the half mirror (I = I0·T·(1-T)). Note that there is actually a loss equivalent to the above X, but X is a very small value and is not considered here.

[0051] Since the amount of light in the normal optical path does not depend on the position of the lens, the amount of light I′ transmitted through the reflective polarizing plate 44 around the lens 42 is the same as the amount of light I (I′=I0·T·(1−T) (Formula 3)).

[0052] Here, according to equation 1 and equation 2, I' G =aI G , which means that the amount of stray light at the periphery of the lens 42 is a times higher than that near the center (a>1).

[0053] In addition, according to equations 2 and 3, the ratio of the amount of stray light around the lens 42 to the amount of light in the normal light path is I'. G / I'=(I0·T·aX) / (I0·T·(1-T))=aX / (1-T).

[0054] Next, as a structural example 1 of one embodiment of the present invention, Figure 4B The basic structure is Figure 4A Again, the difference is that: Figure 4B In the half mirror 41, the transmittance (T') of the peripheral part is equivalent to Figure 2 and Figure 3 The transmittance (T) near the center of the central region B shown is small (T>T').

[0055] In order to make the half mirror 41 have the above transmittance, for example, the following structure can be adopted: Fig. 6A As shown in the front view of FIG, the transmittance of the area C corresponding to the central area B is set to 0.5, and the transmittance is continuously reduced toward the edge. Note that the transmittance of the entire optical device can also be reduced by making the transmittance of the half mirror 41 higher than 0.5 toward the edge, but according to Formula 2, the stray light increases, so the transmittance of the half mirror 41 is lower than 0.5 toward the edge.

[0056] The amount of light in the normal optical path of the half mirror 41 is transmittance + reflectance = 1, which is a quadratic function of the transmittance T, so the midpoint is the extreme value. That is, the transmittance of area C is the highest when the transmittance is 0.5 and the reflectance is 0.5. Note that Figure 2 and Figure 3 The edge of the field of view A shown is not limited to the outer periphery of the half mirror 41 , but may be the inner side of the half mirror 41 .

[0057] The above-mentioned semi-reflective mirror can be manufactured by using a gray-tone resist mask to etch a metal film or a dielectric film formed on a support in a manner having a thickness gradient in the plane. Alternatively, it can also be manufactured by performing a deposition process multiple times using a metal mask or the like having different opening sizes.

[0058] Similar to Equation 1, the amount of stray light I generated near the center of the optical device G is I G = I0·T·X (Equation 4).

[0059] In addition, when the X value at the periphery of the lens 42 is a times higher (a > 1) than that near the center, the amount of stray light I' G is I' G = I0·T'·aX (Equation 5).

[0060] Here, when assuming T' = mT (0 < m < 1) based on T > T', according to Equation 4 and Equation 5, I' G = I0·mT·aX = amI G . In Figure 4A the structure shown, I' G = aI G and m is less than 1, so it can be said that Figure 4B the amount of stray light generated at the periphery of the lens 42 in the structure shown is less than Figure 4A the comparative example shown.

[0061] Similar to Figure 4A the comparative example, near the center of the optical device, the amount of light I transmitted through the reflective polarizer 44 (the amount of light in the normal optical path) is I = I0·T·(1 - T).

[0062] In addition, the amount of light I' transmitted through the reflective polarizer 44 at the periphery of the lens 42 is I' = I0·T'·(1 - T') (Equation 6).

[0063] In addition, according to Equation 5 and Equation 6, the ratio of the amount of stray light to the amount of light in the normal optical path at the periphery of the lens 42 is I' G / I' = (I0·T'·aX) / (I0·T'·(1 - T')) = aX / (1 - T') = aX / (1 - mT). In Figure 4A the structure of, I' G / I' = aX / (1 - T) and m is less than 1, so it can be said that Figure 4B the ratio of the amount of stray light to the amount of regular light at the periphery of the lens 42 in the structure shown is less than Figure 4A the comparative example shown.

[0064] That is to say, in Figure 4B the structure shown, the amount of stray light at the peripheral part of the lens 42 can be made less than Figure 4AThe comparative example shown. In addition, the amount of light in the normal optical path in the peripheral portion is less than that in the comparative example, but the ratio of stray light to the amount of light in the normal optical path can be made smaller than that in the comparative example. Thus, the visibility of the display can be improved.

[0065] Next, as Structural Example 2 of one aspect of the present invention, the Figure 5A structure shown will be described. The basic structure of the optical device is the same as that of Figure 4A the same, and the display image obtained by processing the data of the original image so as to increase the brightness reduction rate from the vicinity of the center to the edge is used as the incident light. Here, the amount of incident light in the vicinity of the center is I0 and the amount of incident light in the peripheral portion is I1 (I0 > I1).

[0066] Similar to Equation 1, the amount of stray light I G generated in the vicinity of the center of the optical device is I G = I0·T·X (Equation 7).

[0067] In addition, when the X value in the periphery of the lens 42 is a times higher than that in the vicinity of the center (a > 1), the amount of stray light I' G is I' G = I1·T·aX (Equation 8).

[0068] Here, when assuming I1 = mI0 (0 < m < 1) based on I0 > I1, according to Equation 7 and Equation 8, I' G = mI0·T·aX = amI G . In the Figure 4A comparative example shown, I' G = aI G and m is less than 1, so it can be said that Figure 5A the amount of stray light generated in the periphery of the lens 42 in the structure shown is less than that in the Figure 4A comparative example shown.

[0069] Similar to Figure 4A the same, in the vicinity of the center of the optical device, the amount of light I (the amount of light in the normal optical path) transmitted through the reflective polarizer 44 is I = I0·T·(1 - T).

[0070] In addition, the amount of light I' transmitted through the reflective polarizer 44 in the periphery of the lens 42 is I' = I1·T·(1 - T) = mI0·T·(1 - T) (Equation 9).

[0071] In addition, according to Equation 8 and Equation 9, the ratio of the amount of stray light to the amount of light in the normal optical path in the periphery of the lens 42 is I' G / I' = (I1·T·aX) / (I1·T·(1 - T)) = aX / (1 - T).

[0072] That is, it is possible to Figure 5AIn the structure shown, the amount of stray light in the peripheral portion of the lens 42 is less than Figure 4A that in the comparative example shown. In addition, the amount of light in the normal optical path in the peripheral portion of the lens 42 is small, but the ratio of stray light to the amount of light in the normal optical path can be made not to increase and be the same as that in the comparative example. Thereby, the visibility of the display can be improved.

[0073] Next, as a structural example 3 of one aspect of the present invention, the structure shown Figure 5B will be described. The basic structure is a structure in which a light attenuation filter 46 is added to Figure 4A it. The light attenuation filter 46 can be provided on the incident surface side of the half mirror 41, between the reflective polarizer 44 and the lens 45, or on the outgoing surface side of the lens 45. Figure 5B An example in which the light attenuation filter 46 is provided on the incident surface side of the half mirror 41 is shown.

[0074] Note that when the light attenuation filter 46 is provided between the lens 42 and the retardation plate 43, the effect of reducing the amount of stray light can also be obtained. However, the stray light passes through the light attenuation filter multiple times in the normal optical path, and the ratio of the amount of stray light to the regular amount of light is higher than that of other structures. Therefore, the light attenuation filter 46 is preferably provided at the above positions.

[0075] In the light attenuation filter 46, the transmittance (F') in the peripheral portion is less than the transmittance (F) near the center (F > F'). In order for the light attenuation filter 46 to have the above transmittance, for example, as Figure 6B shown, a structure in which the transmittance of the region C corresponding to the central region B is the highest and the transmittance continuously decreases toward the edge can be adopted. For example, when the relative transmittance of the region C is 1, the transmittance of the edge can be set to a value less than 1 such as 0.5 or the like. Note that Figure 2 and Figure 3 the end portions of the field of view A shown are not limited to the outer periphery of the light attenuation filter 46 and can also be inside the light attenuation filter 46.

[0076] The amount of stray light I G generated near the center of the optical device is G I = I0·F·T·X (Formula 10).

[0077] In addition, when the ratio of the light passing through the reflective polarizer in the periphery of the lens is a times higher (a > 1) than that near the center, the amount of stray light I' G is G I' = I0·F'·T·aX (Formula 11).

[0078] Here, when assuming F' = mF (0 < m < 1) based on F > F', according to Formula 10 and Formula 11, I' G = I0·mF·T·aX = amIG .exist Figure 4A In the comparative example shown, I' G =aI G And m is less than 1, so we can say Figure 5B The structure shown produces less stray light around the lens 42 than Figure 4A Comparative example shown.

[0079] Near the center of the optical device, the amount of light I (the amount of light on the normal optical path) transmitted through the reflective polarizing plate 44 is I=I0·F·T·(1-T).

[0080] Furthermore, the amount of light I′ transmitted through the reflective polarizing plate 44 around the lens 42 is I′=I0·F′·T·(1-T)=I0·mF·T·(1-T) (Formula 12).

[0081] In addition, according to equations 11 and 12, the ratio of the amount of stray light around the lens 42 to the amount of light in the normal light path is I'. G / I'=(I0·F'·T·aX) / (I0·F'·T·(1-T))=aX / (1-T).

[0082] That is to say, you can Figure 5B The structure shown makes the amount of stray light at the periphery of the lens 42 less than Figure 4A The comparative example shown. In addition, the amount of light in the normal optical path at the periphery of the lens 42 is small, but the ratio of stray light to the amount of light in the normal optical path can be kept the same as that of the comparative example without increasing the ratio. Thus, the visibility of the display can be improved.

[0083] In addition, FIG. 4A to FIG. 5B , the stray light (I G , I' G ), but sometimes Fig. 7A As shown in FIG. 1 , light I reflected on the surface (second surface) of lens 42 SR When the half mirror 41 is formed on the first surface of the lens 42, the number of times the light passes through the second surface of the lens 42 in the normal optical path is three, and therefore, it is easily affected by surface reflection.

[0084] Therefore, if Figure 7B As shown, due to light I SR When there is much stray light, a half mirror 41 may be provided on the second surface of the lens 42. Figure 7B In the structure shown, light passes through the second surface of the lens 42 only once, so it is not easily affected by surface reflection, so stray light can be reduced. Figure 7B The structure shown can be applied to Figure 4B To the structure shown in Figure 5C.

[0085] Figure 8 FIG. 4 is a diagram for explaining an electronic device including a display device 30 and an optical device 40, and a portion of an optical path is indicated by a dotted line. In addition, for the sake of clarity, several components that can be arranged in a manner close to each other are shown separately. Note that, here, the main focus is on the use of Figure 4B The situation of the structure described in will be explained.

[0086] The user can see the image displayed by the display device 30 by bringing the eye 10 close to the optical device 40. The user can see the image in a state where the viewing angle is enlarged by the optical device 40, thereby obtaining a sense of immersion and reality.

[0087] The display device 30 has a structure in which a display panel 31, a linear polarizing plate 32, and a phase difference plate 33 are arranged to have overlapping regions. Note that in the following description, a first surface is a surface of each component, and a second surface is a surface opposite to the first surface.

[0088] For example, the following structure may be adopted: the display portion of the display panel 31 is close to the first surface of the linear polarizing plate 32; and the second surface of the linear polarizing plate 32 is close to the first surface of the phase difference plate 33. Note that the combination of the linear polarizing plate 32 and the phase difference plate 33 is also called a circular polarizing plate that converts non-polarized light into circularly polarized light.

[0089] Note that the linear polarizing plate 32 and the phase difference plate 33 may not be components of the display device 30 but may be provided between the display device 30 (display panel 31) and the optical device 40. Alternatively, they may be arranged on the light incident surface side of the optical device 40 (the incident surface side of the half mirror 41) as components of the optical device 40. Alternatively, the linear polarizing plate 32 and the phase difference plate 33 may be components of the display device 30 and the optical device 40, respectively.

[0090] The optical device 40 has an area where the half mirror 41, the lens 42, the phase difference plate 43, the reflective polarizer 44, and the lens 45 overlap each other. In addition, the optical axes of the lenses 42 and 45 are arranged so as to intersect perpendicularly with the display portion of the display panel 31. In addition, when the neutral density filter 46 is provided, it is preferably provided on the incident surface side of the half mirror 41, between the reflective polarizer 44 and the lens 45, or on the emission surface side of the lens 45. Figure 8 , an example is shown in which the neutral density filter 46 is provided on the incident surface side of the half mirror 41.

[0091] Note that “perpendicular” means that the two straight lines form an angle of 85° or more and 95° or less. Here, one of the two straight lines represents the optical axis of the lens 42 and the lens 45, and the other represents a straight line parallel to the display unit (display surface).

[0092] For example, the first surface of the half mirror 41 may be close to the first surface of the lens 42. Alternatively, the first surface of the phase difference plate 43 may be close to the first surface of the reflective polarizer 44, and the second surface of the reflective polarizer 44 may be close to the first surface of the lens 45.

[0093] In order to ensure a required optical path length, the half mirror 41 and the lens 42 may be arranged separately. In addition, the lens 42 and the phase difference plate 43 may be arranged close to each other.

[0094] Note that in order to realize the structure in which one component is close to another component, it is preferable to use an optical adhesive having high transmittance for the wavelength of light used (for example, the wavelength range of visible light or the wavelength range of blue light to red light) and no absorption and birefringence of specific polarized light to bond the components together. Alternatively, another component in contact with one component may be formed by coating or the like instead of bonding. Alternatively, an adhesive or the like may not be arranged between one component and another component, and the two may be disposed in contact. Alternatively, a gap may be provided between the two.

[0095] Note that in Figure 8 Even when the components of the display device 30 and the optical device 40 are separately arranged as shown, the effect of one embodiment of the present invention can be obtained.

[0096] Part of the light emitted from the display panel 31 passes through the linear polarizing plate 32, the phase difference plate 33, the half mirror 41, the lens 42, and the phase difference plate 43, and is reflected by the reflective polarizing plate 44. The light reflected by the reflective polarizing plate 44 passes through the phase difference plate 43 and the lens 42, and is reflected by the half mirror 41. The light reflected by the half mirror 41 passes through the lens 42, the phase difference plate 43, the reflective polarizing plate 44, and the lens 45, and is collected and emitted to the eye 10.

[0097] In this way, since the optical path length can be ensured by repeating reflection in the optical device 40, an optical system with a short focal distance can be realized.

[0098] As the display panel 31, a liquid crystal panel including a liquid crystal element, an organic EL panel including an organic EL element, or an LED panel including a Micro LED (Light Emitting Diode) can be used. In particular, it is preferable to use an organic EL panel that is self-luminous and easy to form a high-definition display portion. Note that in this specification, Micro LED refers to a chip area of ​​10000μm 2 In addition, in LED panels, it is not limited to Micro LEDs, for example, LEDs with a chip area larger than 10000μm can also be used.2 And 1mm 2 The following light-emitting diodes (also called Mini LEDs).

[0099] The linear polarizer 32 can extract a linear polarized light from the light vibrating in all directions of 360°. Note that in this embodiment, the transmission axis of the linear polarizer 32 is described as 0°, but 0° is not an absolute value but a reference value. That is, the polarization plane of the linear polarized light extracted by the linear polarizer 32 is taken as 0°. Therefore, for example, the 90° linear polarized light in this embodiment refers to the linear polarized light whose polarization plane is rotated 90° from the linear polarizer 32.

[0100] The phase difference plate 33 has the function of converting linear polarized light into circular polarized light. Here, a λ / 4 plate (1 / 4 wave plate) is used as the phase difference plate 33. The λ / 4 plate is overlapped on the linear polarizing plate 32 in such a way that the angle between the slow axis of the λ / 4 plate and the linear polarization axis emitted from the linear polarizing plate 32 is 45°, thereby becoming right-handed circularly polarized light (right circularly polarized light). In addition, the λ / 4 plate is overlapped on the linear polarizing plate 32 in such a way that the angle between the slow axis of the λ / 4 plate and the linear polarization axis emitted from the linear polarizing plate 32 is -45°, thereby becoming left-handed circularly polarized light (left circularly polarized light). In one embodiment of the present invention, as long as the combination with the characteristics of the reflective polarizing plate 44 described later is appropriate, right circularly polarized light or left circularly polarized light can be used.

[0101] As the half mirror 41, for example, the following structure can be adopted: optical glass or optical resin material with high visible light transmittance is used as a support body; and the surface provided with a metal film or a dielectric film is used as a reflecting surface. Fig. 6A The structure described in .

[0102] In addition, the reflecting surface of the half mirror 41 preferably has a positive refractive power so as to focus light in the direction of the eye 10. Therefore, the surface used for the reflecting effect of the half mirror 41 is preferably a concave surface. Here, an example is shown in which a convex meniscus lens is used as the lens 42 and a half mirror 41 is provided on one surface thereof. In addition, the half mirror 41 may also be provided on a support body different from the lens 42.

[0103] A convex lens can be used as the lens 42. Figure 8An example of using a convex meniscus lens as lens 42 is shown, but lens 42 is not limited to the above example. For example, lens 42 may be composed of one or more plano-convex lenses. In addition, a biconvex lens may be used as lens 42. Alternatively, a structure in which a plurality of lenses selected from a biconvex lens, a plano-convex lens, a biconcave lens, a plano-concave lens, a convex meniscus lens, and a concave meniscus lens are combined may be used as lens 42. In addition, lens 42 is not limited to a spherical lens, and may also be an aspherical lens.

[0104] Note that the lens 45 may be the same lens as the lens 42. In addition, the optical device 40 may be provided with lenses other than the lenses 42 and 45.

[0105] The phase difference plate 43 has a function of reversibly converting linear polarization and circular polarization. As with the phase difference plate 33, a λ / 4 plate (1 / 4 wave plate) can be used as the phase difference plate 43.

[0106] The reflective polarizer 44 can transmit linear polarized light whose vibration direction coincides with the transmission axis of the reflective polarizer 44 and reflect linear polarized light whose vibration direction is orthogonal to the transmission axis of the reflective polarizer 44. As the reflective polarizer, for example, a wire grid polarizer or a dielectric multilayer film can be used.

[0107] use Figure 8 The optical paths shown illustrate the details of the polarization states of the optical device 40 described above.

[0108] The light emitted from the display panel 31 and vibrating in all directions of 360° enters the linear polarizing plate 32. The transmission axis of the linear polarizing plate 32 is 0°, and the linear polarizing plate 32 emits 0° linearly polarized light.

[0109] The 0° linearly polarized light emitted from the linear polarizing plate 32 is converted into right circularly polarized light by the phase difference plate 33 . The right circularly polarized light emitted from the phase difference plate 33 passes through the half mirror 41 and enters the lens 42 .

[0110] The right circularly polarized light emitted from the lens 42 is incident on the phase difference plate 43 and converted into 0° linearly polarized light. The 0° linearly polarized light emitted from the phase difference plate 43 is reflected by the reflective polarizing plate 44 having a reflection axis of 0° and is incident on the phase difference plate 43 and converted into right circularly polarized light.

[0111] The right circularly polarized light emitted from the phase difference plate 43 passes through the lens 42, is reflected by the half mirror 41, and is inverted into the left circularly polarized light. The left circularly polarized light inverted by the half mirror 41 passes through the lens 42 and enters the phase difference plate 43, and is converted into 90° linear polarized light. The 90° linear polarized light emitted from the phase difference plate 43 passes through the reflective polarizer 44 and the lens 45 with a transmission axis of 90°, and is incident on the eye 10.

[0112] Thus, by utilizing linear polarized light and circular polarized light, as well as a half mirror and a reflective polarizing plate, selective reflection and transmission can be achieved, thereby ensuring an optical path length within a limited space and shortening the focal length of the optical device.

[0113] Note that, although the example in which right circularly polarized light is used as the light that passes through the half mirror 41 and enters the lens 42 is described above, left circularly polarized light may also be used.

[0114] Notice, Figure 8 The structures of the display device 30 and the optical device 40 shown are just examples, and other structures may be adopted.

[0115] Fig. 9A 1 is a diagram for explaining a display panel 31 included in an electronic device according to one embodiment of the present invention. The display panel 31 includes a pixel array 74, a circuit 75, and a circuit 76. The pixel array 74 includes pixels 70 arranged in the column direction and the row direction.

[0116] The pixel 70 may include a plurality of sub-pixels 71. The sub-pixels 71 have a function of emitting light for display.

[0117] Note that in this specification, although the minimum unit that performs independent operation in a "pixel" is defined as a "sub-pixel" for convenience, "pixel" can be replaced with "region" and "sub-pixel" can be replaced with "pixel".

[0118] The sub-pixel 71 includes a light-emitting device that emits visible light. As the light-emitting device, it is preferred to use an EL element such as OLED (Organic Light Emitting Diode) or QLED (Quantum-dot Light Emitting Diode). As the luminescent material contained in the EL element, there can be cited substances that emit fluorescence (fluorescent materials), substances that emit phosphorescence (phosphorescent materials), substances that exhibit thermally activated delayed fluorescence (thermally activated delayed fluorescence (TADF) materials), inorganic compounds (quantum dot materials, etc.), etc. In addition, as a light-emitting device, LEDs such as Micro LEDs can also be used.

[0119] The circuit 75 and the circuit 76 are driving circuits for driving the sub-pixel 71. The circuit 75 can be used as a source driving circuit, and the circuit 76 can be used as a gate driving circuit. As the circuit 75 and the circuit 76, for example, a shift register circuit or the like can be used.

[0120] In addition, if Fig. 9BAs shown, the following structure may be adopted: circuits 75 and 76 are provided in layer 77; pixel array 74 is provided in layer 78; and layer 77 overlaps layer 78. By adopting this structure, a display device with a narrow frame can be formed.

[0121] In addition, by providing the driving circuit in the lower layer of the pixel array 74, the wiring length can be shortened and the wiring capacitance can be reduced. Thus, a display panel capable of high-speed operation and low power consumption operation can be realized.

[0122] In addition, if Fig. 9B As shown, by dividing and arranging the circuit 75 and the circuit 76, the pixel array 74 can be partially driven. For example, the image data can be partially rewritten in the pixel array 74. In addition, a part of the pixel array 74 can be operated at a different operating frequency.

[0123] Notice, Fig. 9B The configuration and area of ​​the circuit 75 and the circuit 76 shown are only examples and can be changed appropriately. In addition, a part of the circuit 75 and the circuit 76 can also be formed in the same layer as the pixel array 74. In addition, the layer 77 can also be provided with circuits such as a storage circuit, a calculation circuit, and a communication circuit.

[0124] In this structure, for example, layer 77 may be provided on a single crystal silicon substrate, circuits 75 and 76 may be formed using transistors containing silicon in a channel formation region (hereinafter, Si transistors), and pixel circuits included in pixel array 74 provided in layer 78 may be formed using transistors containing metal oxide in a channel formation region (hereinafter, OS transistors). The OS transistor may be formed by stacking a thin film on the Si transistor.

[0125] Note that Fig. 9C As shown, a layer 79 provided with an OS transistor may be included between layer 77 and layer 78. In layer 79, an OS transistor may be used to form a portion of a pixel circuit included in pixel array 74. Alternatively, an OS transistor may be used to form a portion of circuits 75 and 76. Alternatively, an OS transistor may be used to form a portion of a circuit such as a storage circuit, a computing circuit, and a communication circuit that may be provided in layer 77.

[0126] Fig. 10A and Fig. 10B 1 and 2. The figure shows an example of a glasses-type device including the display device 30 and the optical device 40 shown in FIG. 1. Here, the display device 30 and the optical device 40 are combined into a display unit 92 and indicated by a dotted line. The glasses-type device includes two display units 92, and is sometimes referred to as VR glasses, etc., depending on the purpose.

[0127] Two display units 92 are installed in the frame 90 in such a way that the surface of the lens 45 is exposed inside. One display unit 92 is a right-eye display unit, and the other display unit 92 is a left-eye display unit. By using each display unit 92 to display an image corresponding to the parallax, the user can feel the three-dimensional effect of the image.

[0128] In addition, the frame 90 or the belt 91 may also be provided with an input terminal and an output terminal. A cable for supplying an image signal from an image output device or the like or power for charging a battery provided in the frame 90 may be connected to the input terminal. The output terminal is used as a sound output terminal, for example, and may be connected to an earphone or a headset. In addition, in the case where sound data can be output via wireless communication or sound is output from an external image output device, the sound output terminal may not be provided.

[0129] In addition, a wireless communication module and a storage module may also be provided inside the frame 90 or the band 91. The wireless communication module may be used to wirelessly download the content to be viewed and store it in the storage module. Thus, the user can view the downloaded content at any time offline.

[0130] In addition, a sight detection sensor may be provided in the frame 90. For example, operation buttons such as power on, power off, sleep, volume adjustment, channel change, menu display, selection, confirmation, return, and operation buttons such as video play, stop, pause, fast forward, and fast rewind are displayed so that the user can see the operation buttons and perform various operations.

[0131] By using the optical device 40 of one embodiment of the present invention in a glasses-type device, a small, thin, low-power, and highly reliable electronic device can be realized.

[0132] At least a part of this embodiment mode can be implemented in combination with other embodiment modes described in this specification as appropriate.

[0133] (Implementation Method 2) In this embodiment, a structural example of a display panel that can be used in an electronic device according to one embodiment of the present invention is described. The display panel described below can be used as the display panel 31 of Embodiment 1.

[0134] One embodiment of the present invention is a display panel including a light-emitting element (also referred to as a light-emitting device). The display panel includes two or more pixels with different luminous colors. Each pixel includes a light-emitting element. Each light-emitting element includes a pair of electrodes and an EL layer between the pair of electrodes. The light-emitting element is preferably an organic EL element (organic electroluminescent element). The two or more light-emitting elements with different luminous colors each include an EL layer containing different luminescent materials. For example, a full-color display panel can be achieved by including three light-emitting elements that emit red (R), green (G) or blue (B) light, respectively.

[0135] When manufacturing a display panel including a plurality of light-emitting elements with different luminous colors, it is necessary to form at least a layer containing a light-emitting material (light-emitting layer) into an island shape. Here, a method of forming an island-shaped organic film by a vapor deposition method using a shadow mask such as a metal mask is known when forming a part or all of the EL layer separately. However, this method is difficult to achieve high definition and high aperture ratio of the display panel because the shape and position of the island-shaped organic film deviate from the shape and position at the time of design due to various influences such as the accuracy of the metal mask, the misalignment between the metal mask and the substrate, the deflection of the metal mask, and the enlargement of the outline of the deposited film caused by vapor scattering. In addition, during vapor deposition, the film thickness at the end is sometimes reduced due to the blurred outline of the layer. That is, the film thickness of the island-shaped light-emitting layer is sometimes different depending on the position. In addition, when manufacturing a large-scale and high-resolution or high-definition display panel, there is the following concern: due to the low dimensional accuracy of the metal mask and deformation caused by heat, etc., the manufacturing yield is reduced. Therefore, the following measures have been taken: the definition (also called pixel density) is simulated by adopting a special pixel arrangement such as a Pentile arrangement.

[0136] Note that in this specification, etc., "island-shaped" means a state in which two or more layers formed using the same material in the same process are physically separated. For example, an island-shaped light-emitting layer means a state in which the light-emitting layer is physically separated from an adjacent light-emitting layer.

[0137] In one embodiment of the present invention, the EL layer is processed into a fine pattern by photolithography without using a shadow mask such as a fine metal mask (FMM). Therefore, a display panel with high definition and high aperture ratio, which is difficult to achieve at present, can be realized. In addition, since the EL layer can be manufactured separately, a display panel with a very clear and high contrast display quality can be realized. In addition, for example, the EL layer can be processed into a fine pattern by using both a metal mask and photolithography.

[0138] In addition, part or all of the EL layer can be physically separated. Thus, leakage current between light-emitting elements through a layer (also referred to as a common layer) commonly used by adjacent light-emitting elements can be suppressed. Therefore, crosstalk caused by unintentional light emission can be suppressed, thereby realizing a display panel with very high contrast. In particular, a display panel with high current efficiency at low brightness can be realized.

[0139] One embodiment of the present invention can also realize a display panel that combines a white light-emitting light-emitting element and a color filter. In this case, light-emitting elements of the same structure can be used for each light-emitting element in a pixel (sub-pixel) that emits light of different colors, and all layers in each light-emitting element can be used as a common layer. Furthermore, a part or all of each EL layer can be separated by a process utilizing a photolithography method. Thus, the leakage current through the common layer can be suppressed and a display panel with high contrast can be realized. In particular, in an element having a series structure in which a plurality of light-emitting layers are stacked with an intermediate layer having high conductivity, the leakage current through the intermediate layer can be effectively prevented, so a display panel with high brightness, high definition and high contrast can be realized.

[0140] When the EL layer is processed by photolithography, degradation is sometimes caused by the exposure of a portion of the light-emitting layer. Therefore, it is preferred to provide an insulating layer that covers at least the side of the island-shaped light-emitting layer. The insulating layer may also cover a portion of the top surface of the island-shaped EL layer. The insulating layer is preferably made of a material that has a barrier property against water and oxygen. For example, an inorganic insulating film that does not easily diffuse water or oxygen can be used. Thus, the degradation of the EL layer can be suppressed and a display panel with high reliability can be realized.

[0141] In addition, there is an area (recess) between two adjacent light-emitting elements where the EL layer of each light-emitting element is not provided. When a common electrode or a common electrode and a common layer are formed in a manner covering the recess, the common electrode is sometimes broken due to a step at the end of the EL layer (also called disconnection), resulting in the insulation of the common electrode on the EL layer. Therefore, it is preferable to adopt a structure (also called LFP: Local Filling Planarization) in which a resin layer used as a planarization film is used to fill the local step between two adjacent light-emitting elements. The resin layer is used as a planarization film. As a result, the disconnection of the common layer or the common electrode can be suppressed, and a display panel with high reliability can be achieved.

[0142] Hereinafter, a more specific structural example of a display panel according to one embodiment of the present invention will be described with reference to the drawings.

[0143] [Structural example 1] Fig.11AA plan view schematic diagram of a display panel 100 showing one embodiment of the present invention. The display panel 100 includes a plurality of red-emitting elements 110R, a plurality of green-emitting elements 110G, and a plurality of blue-emitting elements 110B on a substrate 101. In Fig.11A For the convenience of distinguishing each light-emitting element, symbols "R", "G", and "B" are attached within the light-emitting regions of the respective light-emitting elements.

[0144] The light-emitting elements 110R, 110G, and 110B are all arranged in a matrix. Fig.11A Shows a so-called stripe arrangement in which light-emitting elements of the same color are arranged in one direction. Note that the arrangement method of the light-emitting elements is not limited to this, and other arrangement methods such as S-stripe arrangement, Delta arrangement, Bayer arrangement, zigzag arrangement, etc. can also be used, and Pentile arrangement, Diamond arrangement, etc. can also be used.

[0145] As the light-emitting elements 110R, 110G, and 110B, OLED (Organic Light Emitting Diode) or QLED (Quantum-dot Light Emitting Diode) is preferably used. As the light-emitting substances included in the EL elements, inorganic compounds (such as quantum dot materials) can also be used in addition to organic compounds.

[0146] In addition, Fig.11A Shows a connection electrode 111C electrically connected to a common electrode 113. The connection electrode 111C is supplied with a potential (for example, an anode potential or a cathode potential) for supplying to the common electrode 113. The connection electrode 111C is provided outside the display area where the light-emitting elements 110R, etc. are arranged.

[0147] The connection electrode 111C can be provided along the outer periphery of the display area. For example, it can be provided along one side of the outer periphery of the display area, or can straddle two or more sides of the outer periphery of the display area. That is, when the top surface shape of the display area is rectangular, the top surface shape of the connection electrode 111C can be strip-shaped (rectangular), L-shaped, "冂"-shaped (bracket-shaped), or quadrilateral, etc. Note that in this specification, etc., the top surface shape refers to the shape when viewed in a plane, that is, the shape when viewed from above.

[0148] Fig. 11B 、 Fig. 11C Are respectively cross-sectional schematic diagrams corresponding to Fig.11A The dotted lines A1 - A2 and A3 - A4 in Fig. 11B Show a cross-sectional schematic diagram of the light-emitting elements 110R, 110G, and 110B, Fig. 11C A schematic cross-sectional view of the connection portion 140 connecting the connection electrode 111C to the common electrode 113 is shown.

[0149] The light emitting element 110R includes a pixel electrode 111R, an organic layer 112R, a common layer 114, and a common electrode 113. The light emitting element 110G includes a pixel electrode 111G, an organic layer 112G, a common layer 114, and a common electrode 113. The light emitting element 110B includes a pixel electrode 111B, an organic layer 112B, a common layer 114, and a common electrode 113. The light emitting element 110R, the light emitting element 110G, and the light emitting element 110B share the common layer 114 and the common electrode 113.

[0150] The organic layer 112R included in the light-emitting element 110R includes a light-emitting organic compound that emits at least red light. The organic layer 112G included in the light-emitting element 110G includes a light-emitting organic compound that emits at least green light. The organic layer 112B included in the light-emitting element 110B includes a light-emitting organic compound that emits at least blue light. The organic layer 112R, the organic layer 112G, and the organic layer 112B can each be referred to as an EL layer, and include at least a layer having a light-emitting substance (light-emitting layer).

[0151] Hereinafter, when describing the common contents among the light-emitting element 110R, the light-emitting element 110G, and the light-emitting element 110B, they are sometimes referred to as the light-emitting element 110. Similarly, when describing the common contents among the constituent elements distinguished by letters, such as the organic layer 112R, the organic layer 112G, and the organic layer 112B, the symbols without letters are sometimes used for description.

[0152] The organic layer 112 and the common layer 114 may independently include one or more of an electron injection layer, an electron transport layer, a hole injection layer, and a hole transport layer. For example, the organic layer 112 has a stacked structure of a hole injection layer, a hole transport layer, a light-emitting layer, and an electron transport layer from one side of the pixel electrode 111, and the common layer 114 includes an electron injection layer.

[0153] The pixel electrode 111R, the pixel electrode 111G and the pixel electrode 111B are all arranged in each light-emitting element. In addition, the common electrode 113 and the common layer 114 are set as a layer commonly used by each light-emitting element. A conductive film that is translucent to visible light is used as one of the pixel electrodes and the common electrode 113, and a conductive film that is reflective is used as the other. By making each pixel electrode translucent and the common electrode 113 reflective, a bottom emission type (bottom emission structure) display panel can be realized. Conversely, by making each pixel electrode reflective and the common electrode 113 translucent, a top emission type (top emission structure) display panel can be realized. In addition, by making both the pixel electrode and the common electrode 113 translucent, a double-sided emission type (double-sided emission structure) display panel can also be realized.

[0154] A protective layer 121 is provided on the common electrode 113 so as to cover the light emitting elements 110R, 110G, and 110B. The protective layer 121 has a function of preventing impurities such as water from diffusing from above to each light emitting element.

[0155] The end of the pixel electrode 111 preferably has a tapered shape. When the end of the pixel electrode 111 has a tapered shape, the organic layer 112 provided along the end of the pixel electrode 111 may also have a tapered shape. By making the side of the pixel electrode 111 have a tapered shape, the coverage of the organic layer 112 provided across the end of the pixel electrode 111 can be improved. In addition, by making the side of the pixel electrode 111 have a tapered shape, foreign matter (for example, dust or particles, etc.) in the manufacturing process can be easily removed by washing treatment, etc., so it is preferred.

[0156] Note that in this specification, etc., a tapered shape means a shape in which at least a portion of the side surface of a component is inclined relative to the substrate surface. For example, it is preferable to have a region in which the angle between the inclined side surface and the substrate surface (also referred to as a taper angle) is less than 90 degrees.

[0157] The organic layer 112 is processed into an island shape by photolithography. Therefore, the organic layer 112 has a shape at its end where the angle between the top surface and the side surface is close to 90 degrees. On the other hand, the film thickness of the organic film formed using FMM or the like tends to become thinner as it approaches the end, for example, its top surface is formed in a slope shape within a range of 1 μm to 10 μm, so it is difficult to distinguish the top surface from the side surface.

[0158] An insulating layer 125 , a resin layer 126 , and a layer 128 are provided between two adjacent light emitting elements.

[0159] Between two adjacent light-emitting elements, the side surfaces of each organic layer 112 face each other via the resin layer 126. The resin layer 126 is located between two adjacent light-emitting elements and is provided in a manner to fill the end of each organic layer 112 and the area between the two organic layers 112. The top surface of the resin layer 126 has a smooth convex shape, and the common layer 114 and the common electrode 113 are provided in a manner to cover the top surface of the resin layer 126.

[0160] The resin layer 126 is used as a planarization film to fill the step between two adjacent light emitting elements. The resin layer 126 can prevent the common electrode 113 on the organic layer 112 from being insulated due to the step at the end of the organic layer 112 (also called disconnection).

[0161] As the resin layer 126, an insulating layer containing an organic material can be suitably used. For example, acrylic resin, polyimide resin, epoxy resin, imide resin, polyamide resin, polyimide amide resin, silicone resin, siloxane resin, benzocyclobutene resin, phenolic resin, and precursors of the above resins can be used as the resin layer 126. In addition, as the resin layer 126, organic materials such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinyl pyrrolidone, polyethylene glycol, polyglycerol, pullulan, water-soluble cellulose, or alcohol-soluble polyamide resin can also be used.

[0162] In addition, a photosensitive resin may be used as the resin layer 126. A photoresist may be used as the photosensitive resin. A positive type material or a negative type material may be used as the photosensitive resin.

[0163] The resin layer 126 may also contain a material that absorbs visible light. For example, the resin layer 126 itself may be composed of a material that absorbs visible light, or the resin layer 126 may contain a pigment that absorbs visible light. As the resin layer 126, for example, the following resins may be used: a resin that can be used as a color filter that transmits red, blue, or green light and absorbs other light; or a resin that contains carbon black as a pigment and is used as a black matrix; etc.

[0164] The insulating layer 125 is in contact with the side surface of the organic layer 112. In addition, the insulating layer 125 covers the upper end portion of the organic layer 112. In addition, a portion of the insulating layer 125 is in contact with the top surface of the substrate 101.

[0165] The insulating layer 125 is located between the resin layer 126 and the organic layer 112 and is used as a protective film to prevent the resin layer 126 from contacting the organic layer 112. When the organic layer 112 and the resin layer 126 are in contact, the organic layer 112 may be dissolved by an organic solvent or the like used when forming the resin layer 126. Therefore, by providing the insulating layer 125 between the organic layer 112 and the resin layer 126, the side surface of the organic layer 112 can be protected.

[0166] The insulating layer 125 may be an insulating layer containing an inorganic material. As the insulating layer 125, an inorganic insulating film such as an oxide insulating film, a nitride insulating film, an oxynitride insulating film, and a nitride oxide insulating film may be used. The insulating layer 125 may be a single-layer structure or a stacked-layer structure. As the oxide insulating film, a silicon oxide film, an aluminum oxide film, a magnesium oxide film, an indium gallium zinc oxide film, a gallium oxide film, a germanium oxide film, an yttrium oxide film, a zirconium oxide film, a lanthanum oxide film, a neodymium oxide film, a hafnium oxide film, and a tantalum oxide film may be mentioned. As the nitride insulating film, a silicon nitride film and an aluminum nitride film may be mentioned. As the oxynitride insulating film, an oxynitride silicon film and an oxynitride aluminum film may be mentioned. As the nitride oxide insulating film, a nitride oxide silicon film and an oxynitride aluminum film may be mentioned. In particular, by using a metal oxide film such as an aluminum oxide film or a hafnium oxide film or an inorganic insulating film such as a silicon oxide film formed by an ALD method for the insulating layer 125, the insulating layer 125 can have fewer pinholes and have an excellent function of protecting the EL layer.

[0167] In this specification, etc., "oxynitride" refers to a material whose composition contains more oxygen than nitrogen, and "nitride oxide" refers to a material whose composition contains more nitrogen than oxygen. For example, "silicon oxynitride" refers to a material whose composition contains more oxygen than nitrogen, and "silicon nitride oxide" refers to a material whose composition contains more nitrogen than oxygen.

[0168] The insulating layer 125 can be formed by a sputtering method, a CVD method, a PLD method, an ALD method, or the like. The insulating layer 125 is preferably formed by an ALD method having good coverage.

[0169] Alternatively, a reflective film (e.g., a metal film containing one or more selected from silver, palladium, copper, titanium, and aluminum) may be provided between the insulating layer 125 and the resin layer 126 to reflect the light emitted by the light-emitting layer. This can further improve light extraction efficiency.

[0170] The layer 128 is a portion of a protective layer (also referred to as a mask layer or a sacrificial layer) that is used to protect the organic layer 112 when etching the organic layer 112. The layer 128 can use a material that can be used for the insulating layer 125. In particular, the layer 128 and the insulating layer 125 are preferably made of the same material, so that the same equipment for processing can be used.

[0171] In particular, metal oxide films such as aluminum oxide films and hafnium oxide films and inorganic insulating films such as silicon oxide films formed by the ALD method have fewer pinholes and are therefore excellent in the function of protecting the EL layer and can be suitably used for the insulating layers 125 and 128 .

[0172] The protective layer 121 may have, for example, a single-layer structure or a stacked-layer structure including at least an inorganic insulating film. Examples of the inorganic insulating film include oxide films or nitride films such as silicon oxide films, silicon oxynitride films, silicon nitride oxide films, silicon nitride films, aluminum oxide films, aluminum oxynitride films, and hafnium oxide films. Alternatively, a semiconductor material or conductive material such as indium gallium oxide, indium zinc oxide, indium tin oxide, and indium gallium zinc oxide may be used as the protective layer 121.

[0173] As the protective layer 121, a laminated film of an inorganic insulating film and an organic insulating film can also be used. For example, it is preferred to sandwich an organic insulating film between a pair of inorganic insulating films. In addition, the organic insulating film is preferably used as a planarizing film. Therefore, the top surface of the organic insulating film can be made flat, so the coverage of the inorganic insulating film thereon is improved, thereby improving the barrier property. In addition, the top surface of the protective layer 121 becomes flat, so when a structure (for example, a color filter, an electrode or a lens array of a touch sensor, etc.) is set above the protective layer 121, the influence of the concave-convex shape caused by the lower structure can be reduced, so it is preferred.

[0174] Fig. 11C The connecting portion 140 that electrically connects the connecting electrode 111C and the common electrode 113 is shown. In the connecting portion 140, an opening is provided in the insulating layer 125 and the resin layer 126 above the connecting electrode 111C. The connecting electrode 111C and the common electrode 113 are electrically connected in the opening.

[0175] Notice, Fig. 11C The connection portion 140 electrically connecting the connection electrode 111C and the common electrode 113 is shown, but the common electrode 113 may be provided on the connection electrode 111C via the common layer 114. In particular, when a carrier injection layer is used as the common layer 114, the resistivity of the material used for the common layer 114 is sufficiently low and the film thickness is also thin, so in many cases there is no problem in positioning the common layer 114 at the connection portion 140. Thus, the common electrode 113 and the common layer 114 can be formed using the same shadow mask, so that the manufacturing cost can be reduced.

[0176] [Structural example 2] Hereinafter, a display panel having a partially different structure from that of the above-described structural example 1 will be described. Note that regarding the same parts as those of the above-described structural example 1, the above-described structural example 1 may be referred to and the description thereof may be omitted.

[0177] Fig. 12A 1 is a schematic cross-sectional view of the display panel 100a. The main differences between the display panel 100a and the display panel 100 are: the structure of the light emitting element; and the former includes a coloring layer.

[0178] The display panel 100a includes a light-emitting element 110W that emits white light. The light-emitting element 110W includes a pixel electrode 111, an organic layer 112W, a common layer 114, and a common electrode 113. The organic layer 112W emits white light. For example, the organic layer 112W may include two or more light-emitting materials whose luminescent colors are in a complementary color relationship. For example, the organic layer 112W may include a light-emitting organic compound that emits red light, a light-emitting organic compound that emits green light, and a light-emitting organic compound that emits blue light. In addition, it may also include a light-emitting organic compound that emits blue light and a light-emitting organic compound that emits yellow light.

[0179] Each organic layer 112W is separated between two adjacent light emitting elements 110W. Thus, leakage current flowing between adjacent light emitting elements 110W through the organic layer 112W can be suppressed, and crosstalk caused by the leakage current can be suppressed. Therefore, a display panel with high contrast and color reproducibility can be realized.

[0180] An insulating layer 122 serving as a planarization film is provided over the protective layer 121 , and the colored layers 116R, 116G, and 116B are provided over the insulating layer 122 .

[0181] As the insulating layer 122, an organic resin film or an inorganic insulating film with a flat top surface can be used. Since the insulating layer 122 is the surface on which the colored layer 116R, the colored layer 116G, and the colored layer 116B are formed, the thickness of the colored layer 116R and the like can be made uniform when the top surface of the insulating layer 122 is flat, thereby improving the color purity. Note that when the thickness of the colored layer 116R and the like is not uniform, the amount of light absorption varies depending on the region in the colored layer 116R, which may cause a decrease in color purity.

[0182] [Structural example 3] Fig. 12B is a schematic cross-sectional view of the display panel 100 b.

[0183] The light emitting element 110R includes a pixel electrode 111, a conductive layer 115R, an organic layer 112W, and a common electrode 113. The light emitting element 110G includes a pixel electrode 111, a conductive layer 115G, an organic layer 112W, and a common electrode 113. The light emitting element 110B includes a pixel electrode 111, a conductive layer 115B, an organic layer 112W, and a common electrode 113. The conductive layer 115R, the conductive layer 115G, and the conductive layer 115B are all light-transmissive and are used as optical adjustment layers.

[0184] A microcavity resonator (microcavity) structure can be realized by using a film that reflects visible light as the pixel electrode 111 and using a film that is both reflective and transparent to visible light as the common electrode 113. At this time, by adjusting the thickness of the conductive layer 115R, the conductive layer 115G, and the conductive layer 115B so as to realize the most suitable optical path length, even if the organic layer 112 that emits white light is used, light of different wavelengths can be extracted from the light-emitting element 110R, the light-emitting element 110G, and the light-emitting element 110B, respectively, and the light can be enhanced.

[0185] Furthermore, by providing the colored layer 116R, the colored layer 116G, and the colored layer 116B on the optical paths of the light emitting element 110R, the light emitting element 110G, and the light emitting element 110B, respectively, light with high color purity can be extracted.

[0186] In addition, an insulating layer 123 is provided to cover the ends of the pixel electrode 111, the conductive layer 115R, the conductive layer 115G, and the conductive layer 115B. The ends of the insulating layer 123 preferably have a tapered shape. By providing the insulating layer 123, the coverage of the organic layer 112W, the common electrode 113, the protective layer 121, etc. formed thereon can be improved.

[0187] The organic layer 112W and the common electrode 113 are respectively provided as a continuous film in each light emitting element. By adopting this structure, the manufacturing process of the display panel can be greatly simplified, so it is preferred.

[0188] Here, the end of the pixel electrode 111 preferably has a substantially vertical shape. Thus, a steeply inclined portion can be formed on the surface of the insulating layer 123, and a thin portion can be formed in a portion of the organic layer 112W covering the portion, or a portion of the organic layer 112W can be separated. Thus, the leakage current generated between adjacent light-emitting elements through the organic layer 112W can be suppressed without processing the organic layer 112W using photolithography or the like.

[0189] The above is a description of the structural example of the display panel.

[0190] [Pixel layout] The following mainly describes Fig.11A Different pixel layouts: There is no particular restriction on the arrangement of light-emitting elements (sub-pixels), and various arrangements can be used.

[0191] As the top surface shape of the sub-pixel, for example, there can be cited polygons such as triangles, quadrilaterals (including rectangles and squares), pentagons, shapes with rounded corners of these polygons, ellipses, circles, etc. Here, the top surface shape of the sub-pixel is equivalent to the top surface shape of the light-emitting region of the light-emitting element.

[0192] Fig.13AThe pixels 150 are shown in an S-stripe arrangement. Fig.13A The pixel 150 shown is composed of three sub-pixels, namely, light emitting elements 110a, 110b, and 110c. For example, the light emitting element 110a, the light emitting element 110b, and the light emitting element 110c may be a blue light emitting element, a red light emitting element, and a green light emitting element, respectively.

[0193] Fig. 13B The pixel 150 shown includes a light-emitting element 110a having a top surface shape that is approximately trapezoidal or triangular with rounded corners, a light-emitting element 110b having a top surface shape that is approximately trapezoidal or triangular with rounded corners, and a light-emitting element 110c having a top surface shape that is approximately quadrilateral or hexagonal with rounded corners. In addition, the light-emitting area of ​​the light-emitting element 110a is larger than that of the light-emitting element 110b. In this way, the shape and size of each light-emitting element can be determined independently. For example, the size of a light-emitting element with high reliability can be smaller. For example, the light-emitting element 110a, the light-emitting element 110b, and the light-emitting element 110c can be a green light-emitting element, a red light-emitting element, and a blue light-emitting element, respectively.

[0194] Fig. 13C The pixels 124a and 124b shown are arranged in a Pentile arrangement. Fig. 13C The example of alternately arranging pixel 124a including light emitting element 110a and light emitting element 110b and pixel 124b including light emitting element 110b and light emitting element 110c is shown. For example, light emitting element 110a, light emitting element 110b and light emitting element 110c may be a red light emitting element, a green light emitting element and a blue light emitting element, respectively.

[0195] Fig.13D and Fig.13E The pixels 124a and 124b shown are arranged in a Delta arrangement. The pixel 124a includes two light-emitting elements (light-emitting elements 110a and 110b) in the upper row (first row) and one light-emitting element (light-emitting element 110c) in the lower row (second row). The pixel 124b includes one light-emitting element (light-emitting element 110c) in the upper row (first row) and two light-emitting elements (light-emitting elements 110a and 110b) in the lower row (second row). For example, the light-emitting element 110a, the light-emitting element 110b, and the light-emitting element 110c may be a red light-emitting element, a green light-emitting element, and a blue light-emitting element, respectively.

[0196] Fig.13D An example is shown in which each light emitting element has a top surface shape that is approximately quadrangular with rounded corners. Fig.13E An example is shown in which each light emitting element has a circular top surface shape.

[0197] Fig.13FAn example in which the light emitting elements of each color are arranged in a zigzag shape is shown. Specifically, in the top view, the positions of the upper sides of two light emitting elements arranged in the column direction (for example, the light emitting element 110a and the light emitting element 110b or the light emitting element 110b and the light emitting element 110c) are not consistent. For example, the light emitting element 110a, the light emitting element 110b, and the light emitting element 110c may be a red light emitting element, a green light emitting element, and a blue light emitting element, respectively.

[0198] In photolithography, the finer the pattern being processed, the more important it is to not ignore the effect of light diffraction. Therefore, when the pattern of the photomask is transferred by exposure, its fidelity decreases, and it is difficult to process the resist mask into a desired shape. Therefore, even if the pattern of the photomask is rectangular, it is easy to form a pattern with rounded corners. Therefore, the top surface shape of the light-emitting element is sometimes a polygonal shape with rounded corners, an ellipse, or a circle.

[0199] Furthermore, in a method for manufacturing a display panel according to one embodiment of the present invention, an EL layer is processed into an island shape using a resist mask. The resist film formed on the EL layer needs to be cured at a temperature lower than the heat resistance temperature of the EL layer. Therefore, depending on the heat resistance temperature of the material of the EL layer and the curing temperature of the resist material, the curing of the resist film is sometimes insufficient. The insufficiently cured resist film sometimes has a shape that is far from the desired shape when processed. As a result, the top surface shape of the EL layer is sometimes a polygonal shape with rounded corners, an ellipse, or a circle. For example, when a resist mask having a square top surface shape is to be formed, a resist mask having a circular top surface shape is sometimes formed and the top surface shape of the EL layer is circular.

[0200] In order to make the top surface shape of the EL layer a desired shape, a technique (OPC (Optical Proximity Correction) technique) of pre-correcting the mask pattern so that the design pattern and the transfer pattern coincide with each other can be used. Specifically, in the OPC technique, correction patterns are added to the pattern corners on the mask pattern.

[0201] The above describes the layout of pixels.

[0202] At least a part of this embodiment mode can be implemented in combination with other embodiment modes described in this specification as appropriate.

[0203] (Implementation method 3) In this embodiment, another structural example of a display panel that can be used for an electronic device according to one embodiment of the present invention is described.

[0204] The display panel of this embodiment is a high-definition display panel, which is particularly suitable for use in the display portion of wearable devices that can be worn on the head, such as VR devices such as head-mounted displays and glasses-type AR devices.

[0205] [Display module] Fig.14A 2 is a perspective view of a display module 280. The display module 280 includes a display panel 200A and an FPC 290. Note that the display panel included in the display module 280 is not limited to the display panel 200A, and may be any one of the display panels 200B to 200F to be described later.

[0206] The display module 280 includes a substrate 291 and a substrate 292. The display module 280 includes a display portion 281. The display portion 281 is a region that displays an image.

[0207] Fig. 14B Schematic perspective view showing the structure of one side of the substrate 291. A circuit portion 282, a pixel circuit portion 283 on the circuit portion 282, and a pixel portion 284 on the pixel circuit portion 283 are stacked on the substrate 291. In addition, a terminal portion 285 for connecting to the FPC 290 is provided on a portion of the substrate 291 that does not overlap with the pixel portion 284. The terminal portion 285 and the circuit portion 282 are electrically connected via a wiring portion 286 composed of a plurality of wirings.

[0208] The pixel portion 284 includes a plurality of pixels 284 a arranged periodically. Fig. 14B An enlarged view of one pixel 284a is shown on the right side of FIG. The pixel 284a includes a light-emitting element 110R that emits red light, a light-emitting element 110G that emits green light, and a light-emitting element 110B that emits blue light.

[0209] The pixel circuit unit 283 includes a plurality of pixel circuits 283a arranged periodically. One pixel circuit 283a controls the light emission of three light emitting devices included in one pixel 284a. One pixel circuit 283a may include three circuits for controlling the light emission of one light emitting device. For example, the pixel circuit 283a may adopt a structure having at least one selection transistor, one current control transistor (driving transistor) and a capacitor for one light emitting device. At this time, a gate signal is input to the gate of the selection transistor, and a source signal is input to the source. Thus, an active matrix display panel can be realized.

[0210] The circuit section 282 includes a circuit for driving each pixel circuit 283a of the pixel circuit section 283. For example, it is preferable to include one or both of a gate line driving circuit and a source line driving circuit. In addition, it may also include at least one of an operation circuit, a storage circuit, and a power supply circuit. In addition, the transistor provided in the circuit section 282 may also constitute a part of the pixel circuit 283a. That is, the pixel circuit 283a may also be constituted by the transistor included in the pixel circuit section 283 and the transistor included in the circuit section 282.

[0211] The FPC 290 is used as wiring for supplying video signals, power supply potential, and the like from the outside to the circuit portion 282. In addition, an IC may be mounted on the FPC 290.

[0212] The display module 280 can adopt a structure in which one or both of the pixel circuit unit 283 and the circuit unit 282 are overlapped on the lower side of the pixel unit 284, so that the display unit 281 can have an extremely high aperture ratio (effective display area ratio). For example, the aperture ratio of the display unit 281 can be 40% or more and less than 100%, preferably 50% or more and 95% or less, and more preferably 60% or more and 95% or less. In addition, the pixels 284a can be arranged at an extremely high density, thereby making the display unit 281 have an extremely high definition. For example, the display unit 281 preferably arranges the pixels 284a with a definition of 2000ppi or more, more preferably 3000ppi or more, more preferably 5000ppi or more, and more preferably 6000ppi or more and 20000ppi or less or 30000ppi or less.

[0213] This display module 280 is very clear, so it is suitable for use in VR devices such as head-mounted displays or glasses-type AR devices. For example, because the display module 280 has a display unit 281 with extremely high clarity, in the structure of viewing the display unit of the display module 280 through a lens, even if the display unit is magnified by a lens, the user cannot see the pixels, thereby achieving a highly immersive display. In addition, the display module 280 can also be applied to electronic devices with a relatively small display unit. For example, it is suitable for the display unit of wearable electronic devices such as watch-type devices.

[0214] [Display panel 200A] Fig.15 The display panel 200A shown includes a substrate 301 , light emitting elements 110R, 110G, 110B, a capacitor 240 , and a transistor 310 .

[0215] Substrate 301 is equivalent to Fig.14A and Fig. 14B The substrate 291 in.

[0216] The transistor 310 is a transistor having a channel formation region in the substrate 301. As the substrate 301, for example, a semiconductor substrate such as a single crystal silicon substrate can be used. The transistor 310 includes a portion of the substrate 301, a conductive layer 311, a low resistance region 312, an insulating layer 313, and an insulating layer 314. The conductive layer 311 is used as a gate electrode. The insulating layer 313 is located between the substrate 301 and the conductive layer 311, and is used as a gate insulating layer. The low resistance region 312 is a region doped with impurities in the substrate 301, and is used as one of a source and a drain. The insulating layer 314 covers the side of the conductive layer 311.

[0217] Furthermore, an element isolation layer 315 is provided between two adjacent transistors 310 so as to be embedded in the substrate 301 .

[0218] In addition, an insulating layer 261 is provided to cover the transistor 310 , and the capacitor 240 is provided over the insulating layer 261 .

[0219] The capacitor 240 includes a conductive layer 241, a conductive layer 245, and an insulating layer 243 therebetween. The conductive layer 241 serves as one electrode of the capacitor 240, the conductive layer 245 serves as the other electrode of the capacitor 240, and the insulating layer 243 serves as a dielectric of the capacitor 240.

[0220] The conductive layer 241 is provided on the insulating layer 261 and embedded in the insulating layer 254. The conductive layer 241 is electrically connected to one of the source and the drain of the transistor 310 through the plug 271 embedded in the insulating layer 261. The insulating layer 243 is provided to cover the conductive layer 241. The conductive layer 245 is provided in a region overlapping the conductive layer 241 via the insulating layer 243.

[0221] The cover capacitor 240 is provided with an insulating layer 255 a , an insulating layer 255 b is provided on the insulating layer 255 a , and an insulating layer 255 c is provided on the insulating layer 255 b .

[0222] Inorganic insulating films can be used as appropriate for the insulating layers 255a, 255b, and 255c. For example, it is preferable to use silicon oxide films as the insulating layers 255a and 255c, and to use a silicon nitride film as the insulating layer 255b. Thus, the insulating layer 255b can be used as an etching protection film. Although an example in which a portion of the insulating layer 255c is etched to provide a recess is shown in this embodiment, the recess may not be provided in the insulating layer 255c.

[0223] The light emitting element 110R, the light emitting element 110G, and the light emitting element 110B are provided on the insulating layer 255 c. The structure of the light emitting element 110R, the light emitting element 110G, and the light emitting element 110B can refer to Embodiment 2.

[0224] The display panel 200A forms light-emitting elements for each light-emitting color, so the chromaticity change between low-brightness light and high-brightness light is small. In addition, the organic layers 112R, 112G, and 112B are separated from each other, so even if a high-definition display panel is used, crosstalk between adjacent sub-pixels can be suppressed. Therefore, a high-definition and high-quality display panel can be realized.

[0225] An insulating layer 125 , a resin layer 126 , and a layer 128 are provided in a region between adjacent light emitting elements.

[0226] The pixel electrode 111R, the pixel electrode 111G, and the pixel electrode 111B of the light-emitting element are electrically connected to one of the source and the drain of the transistor 310 via the plug 256 embedded in the insulating layer 255a, the insulating layer 255b, and the insulating layer 255c, the conductive layer 241 embedded in the insulating layer 254, and the plug 271 embedded in the insulating layer 261. The height of the top surface of the insulating layer 255c is the same as or substantially the same as the height of the top surface of the plug 256. Various conductive materials can be used as the plug.

[0227] Furthermore, a protective layer 121 is provided on the light emitting elements 110R, 110G, and 110B. A substrate 170 is bonded to the protective layer 121 via an adhesive layer 171 .

[0228] No insulating layer covering the top end of the pixel electrode 111 is provided between two adjacent pixel electrodes 111. Therefore, the interval between adjacent light emitting elements can be made very small. Therefore, a high-definition or high-resolution display panel can be realized.

[0229] [Display panel 200B] Fig.16 The display panel 200B shown has a structure in which a transistor 310A and a transistor 310B are stacked, each of which forms a channel in a semiconductor substrate. Note that in the description of the display panel described later, description of the same parts as the display panel described previously may be omitted.

[0230] The display panel 200B has the following structure: a substrate 301B provided with a transistor 310B, a capacitor 240, and a light-emitting device and a substrate 301A provided with a transistor 310A are bonded together.

[0231] Here, an insulating layer 345 is provided on the bottom surface of the substrate 301B, and an insulating layer 346 is provided on the insulating layer 261 provided on the substrate 301A. The insulating layers 345 and 346 are insulating layers that function as protective layers and can suppress diffusion of impurities into the substrates 301B and 301A. As the insulating layers 345 and 346, an inorganic insulating film that can be used for the protective layer 121 or the insulating layer 332 can be used.

[0232] The substrate 301B is provided with a plug 343 that passes through the substrate 301B and the insulating layer 345. Here, it is preferable that an insulating layer 344 serving as a protective layer is provided to cover the side surface of the plug 343.

[0233] In addition, in the substrate 301B, a conductive layer 342 is provided below the insulating layer 345. The conductive layer 342 is embedded in the insulating layer 335, and the bottom surfaces of the conductive layer 342 and the insulating layer 335 are planarized. In addition, the conductive layer 342 is electrically connected to the plug 343.

[0234] On the other hand, in the substrate 301A, a conductive layer 341 is provided over an insulating layer 346. The conductive layer 341 is embedded in the insulating layer 336, and top surfaces of the conductive layer 341 and the insulating layer 336 are planarized.

[0235] It is preferable to use the same conductive material as the conductive layer 341 and the conductive layer 342. For example, a metal film containing an element selected from Al, Cr, Cu, Ta, Ti, Mo, and W or a metal nitride film (titanium nitride film, molybdenum nitride film, tungsten nitride film) containing the above elements as a component can be used. It is particularly preferable to use copper as the conductive layer 341 and the conductive layer 342. Thus, a Cu-Cu (copper-copper) direct bonding technology (a technology for electrically conducting by connecting Cu (copper) pads to each other) can be used.

[0236] [Display panel 200C] Fig.17 The display panel 200C shown has a structure in which a conductive layer 341 and a conductive layer 342 are connected via a bump 347 .

[0237] like Fig.17 As shown, by providing a bump 347 between the conductive layer 341 and the conductive layer 342, the conductive layer 341 and the conductive layer 342 can be electrically connected. The bump 347 can be formed using a conductive material including gold (Au), nickel (Ni), indium (In), tin (Sn), etc. In addition, for example, solder is sometimes used as the bump 347. In addition, an adhesive layer 348 can also be provided between the insulating layer 345 and the insulating layer 346. In addition, when the bump 347 is provided, the insulating layer 335 and the insulating layer 336 may not be provided.

[0238] [Display panel 200D] Fig.18 The main difference between the display panel 200D shown and the display panel 200A is the structure of the transistors.

[0239] The transistor 320 is a transistor (OS transistor) using a metal oxide (also referred to as an oxide semiconductor) in a semiconductor layer forming a channel.

[0240] The transistor 320 includes a semiconductor layer 321 , an insulating layer 323 , a conductive layer 324 , a pair of conductive layers 325 , an insulating layer 326 , and a conductive layer 327 .

[0241] Substrate 331 is equivalent to Fig.14A and Fig. 14B The substrate 291 in.

[0242] An insulating layer 332 is provided over the substrate 331. The insulating layer 332 functions as a barrier layer that prevents impurities such as water and hydrogen from diffusing from the substrate 331 to the transistor 320 and prevents oxygen from escaping from the semiconductor layer 321 to the insulating layer 332 side. As the insulating layer 332, for example, a film into which hydrogen or oxygen is less likely to diffuse than a silicon oxide film, such as an aluminum oxide film, a hafnium oxide film, or a silicon nitride film, can be used.

[0243] A conductive layer 327 is provided on the insulating layer 332, and an insulating layer 326 is provided so as to cover the conductive layer 327. The conductive layer 327 functions as a first gate electrode of the transistor 320, and a portion of the insulating layer 326 functions as a first gate insulating layer. An oxide insulating film such as a silicon oxide film is preferably used for at least a portion of the insulating layer 326 that contacts the semiconductor layer 321. The top surface of the insulating layer 326 is preferably planarized.

[0244] The semiconductor layer 321 is provided on the insulating layer 326. The semiconductor layer 321 preferably includes a metal oxide (also referred to as an oxide semiconductor) film exhibiting semiconductor characteristics. A pair of conductive layers 325 are in contact with the semiconductor layer 321 and function as a source electrode and a drain electrode.

[0245] An insulating layer 328 is provided so as to cover the top surface and side surfaces of the pair of conductive layers 325 and the side surfaces of the semiconductor layer 321, and an insulating layer 264 is provided on the insulating layer 328. The insulating layer 328 is used as a barrier layer that prevents impurities such as water and hydrogen from diffusing from the insulating layer 264 to the semiconductor layer 321 and oxygen from being released from the semiconductor layer 321. As the insulating layer 328, an insulating film similar to the insulating layer 332 described above can be used.

[0246] The insulating layer 328 and the insulating layer 264 are provided with openings reaching the semiconductor layer 321. The insulating layer 323 and the conductive layer 324 are embedded in the openings and are in contact with the top surface of the semiconductor layer 321. The conductive layer 324 is used as a second gate electrode, and the insulating layer 323 is used as a second gate insulating layer.

[0247] The top surfaces of the conductive layer 324 , the insulating layer 323 , and the insulating layer 264 are planarized so that their heights are uniform or substantially uniform, and the insulating layer 329 and the insulating layer 265 are provided to cover them.

[0248] The insulating layer 264 and the insulating layer 265 function as interlayer insulating layers. The insulating layer 329 functions as a barrier layer that prevents impurities such as water and hydrogen from diffusing from the insulating layer 265 and the like into the transistor 320. The insulating layer 329 can use an insulating film similar to the insulating layer 328 and the insulating layer 332 described above.

[0249] The plug 274 electrically connected to one of the pair of conductive layers 325 is embedded in the insulating layer 265, the insulating layer 329, and the insulating layer 264. Here, the plug 274 preferably includes a conductive layer 274a covering the side surfaces of the openings of the insulating layer 265, the insulating layer 329, the insulating layer 264, and the insulating layer 328 and a portion of the top surface of the conductive layer 325, and a conductive layer 274b in contact with the top surface of the conductive layer 274a. At this time, it is preferable to use a conductive material that does not easily diffuse hydrogen and oxygen as the conductive layer 274a.

[0250] There is no particular limitation on the structure of the transistor included in the display panel of this embodiment. For example, a planar transistor, a staggered transistor, or an inversely staggered transistor may be used. In addition, a top-gate or bottom-gate transistor structure may be used. Alternatively, a gate may be provided above and below the semiconductor layer forming the channel.

[0251] As the transistor 320, a structure in which two gates sandwich a semiconductor layer forming a channel is adopted. Alternatively, the two gates may be connected and the transistor may be driven by supplying the same signal to the two gates. Alternatively, the threshold voltage of the transistor may be controlled by applying a potential for controlling the threshold voltage to one of the two gates and applying a potential for driving to the other.

[0252] There is no particular restriction on the crystallinity of the semiconductor material used for the semiconductor layer of the transistor, and an amorphous semiconductor, a single crystal semiconductor, or a semiconductor other than a single crystal semiconductor having crystallinity (a microcrystalline semiconductor, a polycrystalline semiconductor, or a semiconductor having a crystallized region in part thereof) can be used. When a single crystal semiconductor or a semiconductor having crystallinity is used, it is preferred because it can suppress the degradation of the characteristics of the transistor.

[0253] The band gap of the metal oxide used for the semiconductor layer of the transistor is preferably 2 eV or more, more preferably 2.5 eV or more. By using a metal oxide with a wide band gap, the off-state current of the OS transistor can be reduced.

[0254] The metal oxide preferably contains at least indium or zinc, and more preferably contains indium and zinc. For example, the metal oxide preferably contains indium, M (M is one or more selected from gallium, aluminum, yttrium, tin, silicon, boron, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, magnesium and cobalt) and zinc.

[0255] Alternatively, the semiconductor layer of the transistor may also include silicon. Examples of silicon include amorphous silicon, crystalline silicon (low-temperature polysilicon, single crystal silicon, etc.), and the like.

[0256] As metal oxides that can be used for the semiconductor layer, for example, indium oxide, gallium oxide and zinc oxide can be cited. In addition, the metal oxide preferably contains two or three selected from indium, element M and zinc. Element M is one or more selected from gallium, aluminum, silicon, boron, yttrium, tin, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten and magnesium. In particular, element M is preferably one or more selected from aluminum, gallium, yttrium and tin.

[0257] In particular, as the metal oxide used for the semiconductor layer, an oxide containing indium, gallium and zinc (also referred to as IGZO) is preferably used. Alternatively, an oxide containing indium, tin and zinc (also referred to as ITZO (registered trademark)) is preferably used. Alternatively, an oxide containing indium, gallium, tin and zinc is preferably used. Alternatively, an oxide containing indium, aluminum and zinc (also referred to as IAZO) is preferably used. Alternatively, an oxide containing indium, aluminum, gallium and zinc (also referred to as IAGZO) is preferably used.

[0258] When the metal oxide used for the semiconductor layer is an In-M-Zn oxide, the atomic ratio of In in the In-M-Zn oxide is preferably greater than the atomic ratio of M. Examples of the atomic ratio of the metal elements in such an In-M-Zn oxide include a composition of In:M:Zn=1:1:1 or in the vicinity thereof, a composition of In:M:Zn=1:1:1.2 or in the vicinity thereof, a composition of In:M:Zn=1:3:2 or in the vicinity thereof, a composition of In:M:Zn=1:3:4 or in the vicinity thereof, a composition of In:M:Zn=2:1:3 or in the vicinity thereof, a composition of In:M:Zn=3:1:2 or in the vicinity thereof, and a composition of In:M:Zn=1:3:4 or in the vicinity thereof. Zn=4:2:3 or a composition in the vicinity thereof, In:M:Zn=4:2:4.1 or a composition in the vicinity thereof, In:M:Zn=5:1:3 or a composition in the vicinity thereof, In:M:Zn=5:1:6 or a composition in the vicinity thereof, In:M:Zn=5:1:7 or a composition in the vicinity thereof, In:M:Zn=5:1:8 or a composition in the vicinity thereof, In:M:Zn=6:1:6 or a composition in the vicinity thereof, In:M:Zn=5:2:5 or a composition in the vicinity thereof. Note that the nearby compositions include a range of ±30% of the desired atomic ratio.

[0259] For example, when the composition with an atomic ratio of In:Ga:Zn=4:2:3 or thereabouts is described, the following cases are included: when In is 4, Ga is 1 or more and 3 or less, and Zn is 2 or more and 4 or less. In addition, when the composition with an atomic ratio of In:Ga:Zn=5:1:6 or thereabouts is described, the following cases are included: when In is 5, Ga is greater than 0.1 and 2 or less, and Zn is 5 or more and 7 or less. In addition, when the composition with an atomic ratio of In:Ga:Zn=1:1:1 or thereabouts is described, the following cases are included: when In is 1, Ga is greater than 0.1 and 2 or less, and Zn is greater than 0.1 and 2 or less.

[0260] The semiconductor layer may also include two or more metal oxide layers with different compositions. For example, a stacked structure of a first metal oxide layer having a composition of In:M:Zn=1:3:4 [atomic ratio] or a composition close thereto and a second metal oxide layer having a composition of In:M:Zn=1:1:1 [atomic ratio] or a composition close thereto disposed on the first metal oxide layer may be appropriately used. In addition, gallium or aluminum is particularly preferably used as the element M.

[0261] In addition, for example, a stacked-layer structure of any one selected from indium oxide, indium gallium oxide, and IGZO and any one selected from IAZO, IAGZO, and ITZO (registered trademark) may be used.

[0262] Examples of crystalline oxide semiconductors include CAAC (c-axis-aligned crystalline)-OS and nc (nanocrystalline)-OS.

[0263] Compared with transistors using amorphous silicon, the field effect mobility of OS transistors is very high. In addition, the leakage current between the source and the drain (also called the off-state current) of the OS transistor in the off state is extremely low, and the charge stored in the capacitor connected in series with the transistor can be maintained for a long period of time. In addition, by using OS transistors, the power consumption of the display panel can be reduced.

[0264] In addition, when the luminance of the light-emitting device included in the pixel circuit is increased, it is necessary to increase the amount of current flowing through the light-emitting device. To this end, it is necessary to increase the source-drain voltage of the driving transistor included in the pixel circuit. Because the source-drain withstand voltage of the OS transistor is higher than that of the Si transistor, a high voltage can be applied between the source and drain of the OS transistor. Therefore, by using the OS transistor as the driving transistor included in the pixel circuit, the amount of current flowing through the light-emitting device can be increased to improve the luminance of the light-emitting device.

[0265] In addition, when the transistor operates in the saturation region, the change in source-drain current of the OS transistor for the change in gate-source voltage is smaller than that of the Si transistor. Therefore, by using the OS transistor as the driving transistor included in the pixel circuit, the current flowing through the source-drain can be determined in detail according to the change in gate-source voltage, so the amount of current flowing through the light-emitting device can be controlled. As a result, the number of grayscales of the pixel circuit can be increased.

[0266] In addition, regarding the saturation characteristics of the current flowing when the transistor operates in the saturation region, compared with the Si transistor, the OS transistor can make a stable current (saturation current) flow even if the source-drain voltage is gradually increased. Therefore, by using the OS transistor as a driving transistor, even if, for example, the current-voltage characteristics of the EL device are uneven, a stable current can flow through the light-emitting device. That is, when the OS transistor operates in the saturation region, even if the source-drain voltage is increased, the source-drain current is almost unchanged, so the light-emitting brightness of the light-emitting device can be stabilized.

[0267] As described above, by using an OS transistor as a driving transistor included in a pixel circuit, “reduction in power consumption”, “increase in light emission brightness”, “multi-gradation”, “suppression of unevenness in light emitting devices”, etc. can be achieved.

[0268] [Display panel 200E] Fig.19 The display panel 200E shown has a structure in which a transistor 320A and a transistor 320B are stacked, each of which includes an oxide semiconductor in a semiconductor forming a channel.

[0269] The structures of the transistor 320A, the transistor 320B and their peripheries may refer to the above-mentioned display panel 200D.

[0270] Note that although a structure in which two transistors including oxide semiconductors are stacked is used here, the present invention is not limited to this structure and, for example, a structure in which three or more transistors are stacked may be used.

[0271] [Display panel 200F] exist Fig. 20 In the display panel 200F shown, a transistor 310 having a channel formed in a substrate 301 and a transistor 320 having a semiconductor layer containing a metal oxide forming the channel are stacked.

[0272] An insulating layer 261 is provided in a manner covering the transistor 310, and a conductive layer 251 is provided on the insulating layer 261. In addition, an insulating layer 262 is provided in a manner covering the conductive layer 251, and a conductive layer 252 is provided on the insulating layer 262. Both the conductive layer 251 and the conductive layer 252 are used as wiring. In addition, an insulating layer 263 and an insulating layer 332 are provided in a manner covering the conductive layer 252, and a transistor 320 is provided on the insulating layer 332. In addition, an insulating layer 265 is provided in a manner covering the transistor 320, and a capacitor 240 is provided on the insulating layer 265. The capacitor 240 is electrically connected to the transistor 320 through a plug 274.

[0273] The transistor 320 can be used as a transistor constituting a pixel circuit. In addition, the transistor 310 can be used as a transistor constituting a pixel circuit or a transistor constituting a driving circuit (gate line driving circuit, source line driving circuit) for driving the pixel circuit. In addition, the transistor 310 and the transistor 320 can be used as transistors constituting various circuits such as an operation circuit or a storage circuit.

[0274] With this structure, not only a pixel circuit but also a driving circuit can be formed directly under the light-emitting device, so the display panel can be miniaturized compared to the case where the driving circuit is provided around the display area.

[0275] [Display Panel 200G] exist Fig.21 In the display panel 200G shown, a transistor 310 having a channel formed in a substrate 301 , and transistors 320A and 320B having semiconductor layers containing metal oxides forming the channels are stacked.

[0276] Transistor 320A can be used as a transistor constituting a pixel circuit. Transistor 310 can be used as a transistor constituting a pixel circuit or a transistor constituting a driving circuit (gate line driving circuit, source line driving circuit) for driving the pixel circuit. Transistor 320B can be used as a transistor constituting a pixel circuit, or as a transistor constituting the above-mentioned driving circuit. In addition, transistor 310, transistor 320A and transistor 320B can be used as transistors constituting various circuits such as an operation circuit or a storage circuit.

[0277] At least a part of this embodiment mode can be implemented in combination with other embodiment modes described in this specification as appropriate. [Explanation of symbols]

[0278] 10: eye, 30: display device, 31: display panel, 32: linear polarizer, 33: phase difference plate, 40: optical device, 41: half mirror, 42: lens, 43: phase difference plate, 44: reflective polarizer, 45: lens, 46: neutral density filter, 70: pixel, 71: sub-pixel, 74: pixel array, 75: circuit, 76: circuit, 77: layer, 78: layer, 79: layer, 90: housing, 91: belt, 92: display unit, 100a: display panel, 100b: display panel, 100: display panel, 101: substrate, 110a: light emitting element, 110B: light emitting element, 110b: light emitting element, 110c: light emitting element, 110G: light emitting element, 11 0R: light emitting element, 110W: light emitting element, 110: light emitting element, 111B: pixel electrode, 111C: connecting electrode, 111G: pixel electrode, 111R: pixel electrode, 111: pixel electrode, 112B: organic layer, 112G: organic layer, 112R: organic layer, 112W: organic layer, 112: organic layer, 113: common electrode, 114: common layer, 115B: conductive layer, 115G: conductive layer, 115R: conductive layer, 116B: coloring layer, 116G: coloring layer, 116R: coloring layer, 121: protective layer, 122: insulating layer, 123: insulating layer, 124a: pixel, 124b: pixel, 125: insulating layer, 126: resin layer, 128 : layer, 140: connection part, 150: pixel, 170: substrate, 171: adhesive layer, 200A: display panel, 200B: display panel, 200C: display panel, 200D: display panel, 200E: display panel, 200F: display panel, 200G: display panel, 240: capacitor, 241: conductive layer, 243: insulating layer, 245: conductive layer, 251: conductive layer, 252: conductive layer, 254: insulating layer, 255a: insulating layer, 255b: insulating layer, 255c: insulating layer, 256: plug, 261: insulating layer, 262: insulating layer, 263: insulating layer, 264: insulating layer, 265: insulating layer, 271: plug, 274a: conductive layer, 2 74b: conductive layer, 274: plug, 280: display module, 281: display unit, 282: circuit unit, 283a: pixel circuit, 283: pixel circuit unit, 284a: pixel, 284: pixel unit, 285: terminal unit, 286: wiring unit, 290: FPC, 291: substrate, 292: substrate, 301A: substrate, 301B: substrate, 301: substrate, 310A: transistor, 310B: transistor, 310: transistor, 311: conductive layer, 312: low resistance region, 313: insulating layer, 314: insulating layer, 315: element separation layer, 320A: transistor, 320B: transistor, 320: transistor, 321: semiconductor layer, 323: insulating layer,324: conductive layer, 325: conductive layer, 326: insulating layer, 327: conductive layer, 328: insulating layer, 329: insulating layer, 331: substrate, 332: insulating layer, 335: insulating layer, 336: insulating layer, 341: conductive layer, 342: conductive layer, 343: plug, 344: insulating layer, 345: insulating layer, 346: insulating layer, 347: bump, 348: adhesive layer.

Claims

1. An electronic device, comprising: Display panel; as well as Optical equipment, Wherein, the optical device comprises: A first function of focusing light emitted by the display panel to emit light to the user's eyes; and a second function of partially reducing the brightness of light emitted by the display panel, Furthermore, an image can be seen by continuously increasing a brightness reduction rate of light emitted from the display panel from a central area of ​​the field of view to an edge of the field of view.

2. The electronic device according to claim 1, wherein the optical device comprises a half-reflecting mirror, And the half mirror has a region where transmittance decreases continuously from the inside to the outside.

3. The electronic device according to claim 1, wherein the optical device comprises a neutral density filter, Furthermore, the neutral density filter has a region where transmittance decreases continuously from the inside to the outside.

4. The electronic device according to any one of claims 1 to 3, The central area is a range of 20° to 40° including the center of the field of view.

5. The electronic device according to any one of claims 1 to 3, When the transmittance of the optical device corresponding to the central area is 1, the transmittance of the optical device corresponding to the edge of the field of view is greater than or equal to 0.3 and less than or equal to 0.

7.

6. The electronic device according to any one of claims 1 to 3, The display panel includes an organic EL element.

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