Display apparatus

Abstract

The purpose of the present invention is to provide a more suitable display apparatus. The present invention contributes to Sustainable Development Goal "9: Industry, Innovation and Infrastructure". A display apparatus comprises: a display panel 11 capable of emitting video light to a projection member; and a light source device 12 for emitting light to the display panel 11. A transparent member 130 in which decorative print layers 131, 132 are laminated is arranged in an emission direction of the video light emitted from the display panel 11. The video light is reflected by the projection member, and a video generated by the display panel 11 is visually recognized as a virtual image.

Description

display device

[0001] The present invention relates to a display device.

[0002] BACKGROUND ART Virtual image display devices or head-up displays (HUDs) are known that project image light onto a projection member to form a virtual image and display, for example, traffic information such as vehicle route information and congestion information, and vehicle information such as remaining fuel and coolant temperature.

[0003] Japanese Patent Application Publication No. 3-169752

[0004] The display device is placed, for example, on the dashboard of a vehicle. In such a placement, the display device can be directly viewed through the image light exit port of the display device, which causes a problem of impairing the design and aesthetic appeal of the dashboard.

[0005] An object of the present invention is to provide a more suitable display device.

[0006] According to the present invention, a display device is provided which includes a display panel capable of emitting image light to a projection member and a light source device which emits light to the display panel, and in which a transparent member on which a decorative printing layer is laminated is arranged in the direction of emission of the image light emitted from the display panel, the image light is reflected by the projection member, and the image generated by the display panel is viewed as a virtual image.

[0007] According to the present invention, a more suitable display device can be realized. Other problems, configurations, and effects will become apparent from the following description of the preferred embodiment of the invention.

[0008] FIG. 1 is a diagram showing a display device. FIG. 2 is a diagram showing an example of a light reflecting portion of a reflecting optical element. FIG. 3 is a diagram showing an example of a reflecting optical element. FIG. 4 is a diagram showing a decorative printed portion used in a display device. FIG. 5 is a diagram showing an example of the configuration of the decorative printed portion. FIG. 6 is a diagram explaining an example of the decorative printed portion. FIG. 7 is a diagram explaining an example of the decorative printed portion. FIG. 8 is a diagram showing an example of the shape of a decorative printed sheet. FIG. 9 is a diagram explaining an example of the shape of a decorative printed sheet. FIG. 10 is a diagram explaining an example of the decorative printed portion. FIG. 11 is a diagram explaining an example of the decorative printed portion. FIG. 12 is a diagram explaining an example of the decorative printed portion. FIG. 13 is a diagram explaining an example of the decorative printed portion. FIG. 14 is a diagram explaining an example of the decorative printed portion. FIG. 15 is a diagram showing a vehicle equipped with a display device. FIG. 16 is a diagram showing a display device and a vehicle controller. FIG. 17 is a diagram showing a vehicle controller. FIG. 18 is a block diagram showing a display device. FIG. 19 is a block diagram showing a display device.

[0009] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In all drawings used to describe the embodiments, identical components are generally designated by the same reference numerals, and repeated description thereof will be omitted. The present invention can be implemented in various other forms. Unless otherwise specified, each component may be singular or plural. The position, size, shape, range, etc. of each component shown in the drawings may not represent the actual position, size, shape, range, etc., in order to facilitate understanding of the invention. Therefore, the present invention is not necessarily limited to the position, size, shape, range, etc., disclosed in the drawings. When there are multiple components having the same or similar functions, they may be described using the same reference numerals with different subscripts. Furthermore, when it is not necessary to distinguish between these multiple components, the subscripts may be omitted.

[0010] For the purpose of explanation, when describing processing by a program, the program, functions, processing units, etc. may be described as the main components, but the main hardware components are the processor, or a controller, device, computer, system, etc. that is configured with the processor, etc. The computer executes processing according to the program read into memory using resources such as memory and communication interfaces as appropriate through the processor. This realizes predetermined functions, processing units, etc. The processor is configured, for example, with semiconductor devices such as a CPU / MPU or GPU. Processing is not limited to software program processing, and can also be implemented using dedicated circuits. Dedicated circuits such as FPGAs, ASICs, and CPLDs can be used.

[0011] FIG. 1A is a diagram showing the configuration of a display device. The display device has an image forming unit 10, which includes a display panel 11 having an image display element and a light source device 12 that emits image light to the display panel 11. The display device uses light emitted from the light source device 12 (i.e., light source light) to project the image light of an image formed on the display panel 11 onto a projection member. The display device may also be referred to as a projection display device. The display panel 11 forms an image to be projected onto the projection member based on image data, and emits the image light (i.e., projection light). The display panel 11 may also be a liquid crystal panel LCD (Liquid Crystal Display) or the like. In this embodiment, the projection member or projection unit that projects the image light is the transmissive-reflective member 7 in FIG. 3 , but is not limited to the transmissive-reflective member 7.

[0012] On the other hand, the display panel 11 is not limited to a liquid crystal panel and may be a screen plate with a diffusion function. As a means for projecting an image onto a screen plate with a diffusion function, a means for projecting an image of a DMD (Digital Micromirror Device) or a liquid crystal panel in combination with a projection lens, or a means using a micro electro mechanical system may be used.

[0013] The light source device 12 includes a light source 20, a reflecting mirror 21, and a reflecting optical element 23a. The light source device 12 may also include a polarization conversion element 22 and a diffuser plate 25. The light source 20 is typically configured to include an LED (Light Emitting Diode) and may be referred to as a backlight unit. The light source 20 is configured with one or more LED light sources, and the plurality of LED light sources may be arranged in a single row or in two or more rows, as long as they are arranged according to the design.

[0014] The reflecting mirror 21 is a component used to reflect light from the light source 20 and adjust it to approximately parallel light or parallel light. The reflecting surface of the reflecting mirror 21 is a parabolic surface, and may have a shape that is asymmetric with respect to the optical axis of the light emitted from the light source 20. The reflecting mirror 21 may also be disposed eccentrically with respect to the light source 20. The reflecting mirror 21 may also be referred to as a reflecting portion or a reflector. In this embodiment, the reflecting mirror 21 will be used for explanation, but a collimating lens may also be used.

[0015] The polarization conversion element 22 is composed of a polarizing beam splitter (PBS) and a retardation film (½λ), and separates incident light into S-polarized light and P-polarized light, and polarizes either the separated S-polarized light or P-polarized light using the retardation film (½λ), thereby outputting the randomly polarized light incident on the polarization conversion element 22 as linearly polarized light. In this embodiment, the polarization conversion element 22 aligns the polarization of the light emitted from the light source 20, thereby achieving high efficiency in image projection.

[0016] The reflective optical element 23a may also be referred to as a light guide or a light guide. The reflective optical element 23a is configured to adjust the angle of incidence of light rays on the display panel 11, and may be, for example, a prism sheet. In this embodiment, the reflective optical element 23a has a light reflecting portion 24 having a prism shape (a jagged shape). Light rays incident on the light reflecting portion 24 are adjusted to a predetermined light distribution and reflected toward the display panel 11. The distribution of light incident on the display panel 11 can be adjusted by the shape, inclination, and surface roughness of the reflective surface of the light reflecting portion 24. Furthermore, the reflective optical element 23a may be, for example, a resin member having a prism shape, and the prism-shaped portion that forms the reflective surface is coated with a reflective film or the like. Therefore, in the structure of FIG. 1A , the optical axis of the light source 20 and the optical axis of the light incident on the display panel 11 are parallel or approximately parallel.

[0017] FIG. 1B shows an example of the light reflecting portion 24 of the reflective optical element 23a. The light reflecting portion 24 may be configured with multiple inclinations on one surface to achieve more precise adjustment of reflected light. The reflective surface may also be configured with multiple or multifaceted surfaces, or may be configured with a curved surface. The light reflecting portion 24 has a sawtooth pattern with multiple reflective surfaces and connecting surfaces alternately arranged. Light incident on the reflective optical element 23a is reflected upward by each reflective surface and then passes through a diffuser 25 to be adjusted to a predetermined light distribution characteristic before entering the display panel 11. The elevation angles α1a, α2a, α3a, α4a, etc. of the reflective surfaces are arbitrarily set to obtain a predetermined light distribution characteristic. Meanwhile, the relative angles β1a, β2a, β3a, β4a, etc. between the reflective surfaces and the connecting surfaces are set to a constant angle regardless of location, preferably an angle of 90 degrees or greater (βna≧90°). When the reflecting optical element 23a is produced by injection molding, the relative angle βna is set to 90 degrees or more, which makes it easier to process the reflecting surface and the connecting surface with a mold.

[0018] As shown in FIG. 1B , by appropriately setting the lengths and ratios of the connecting surfaces Lc1a, Lc2a, Lc3a, etc. and the reflecting surfaces Lr1a, Lr2a, Lr3a, etc. of the light reflecting unit 24, it is possible to realize a light source device in which the illumination range of light reflected by the reflecting optical element 23a can be adjusted to the size (surface size) required for a device such as the display panel 11. Furthermore, by appropriately adjusting the ratio Lr / Lc, it is possible to partially strengthen or weaken the reflected light. For example, the ratio Lr / Lc is adjusted according to the intensity distribution of light incident on the light reflecting unit 24. More specifically, by reducing the ratio Lr / Lc in areas of the light reflecting unit 24 where the intensity of the incident light is high, i.e., by setting the reflecting surface elevation angle αna at a fine pitch, it is possible to precisely control the light reflection direction and uniformly adjust the brightness distribution of light incident on the display panel 11.

[0019] 1A, the diffuser 25 is disposed between the display panel 11 and the reflective optical element 23a. The diffuser 25 uniformly diffuses the incident light from the reflective optical element 23a. The diffuser 25 has the effect of improving the luminance uniformity within the virtual image plane.

[0020] 1A is configured to bend light rays toward the display panel 11 using a light-guiding section having a prism shape, but the reflective optical element 23b shown in FIG. 2 may be configured to be made of a transparent material such as resin or glass, and to include a light entrance section 231, a light reflection section 232, and a light exit section 233, and to control light distribution based on the shapes of these three surfaces. In this case, the light from the light source 20 may be reflected by total reflection in the light reflection section 232, or may be reflected by an Al reflective film or the like coated on the reflective surface. In this structure, the optical axis of the light source 20 and the optical axis of the light incident on the display panel 11 are approximately perpendicular to each other.

[0021] The reflective optical element 23b has the function of internally reflecting and refracting light taken in from the light source 20 as parallel light via the collimator lens and polarization conversion element 22 through the light entrance portion 231, guiding the light in a desired direction and extracting it as planar light having a desired area. The reflective optical element 23b includes a light entrance portion 231 facing the exit surface of the polarization conversion element 22, a light reflection portion 232 forming an inclined surface, and a light exit portion 233 that emits light to the display panel 11. In the light entrance portion 231, the main light ray is deflected by a predetermined angle in a direction that increases the angle of incidence with respect to the light reflection portion 232. That is, the light entrance portion 231 is formed in a curved convex shape that is inclined toward the light source 20. The light reflecting portion 232 has a number of alternating reflective surfaces and connecting surfaces formed in a sawtooth pattern, and light incident on the reflective optical element 23b is reflected on each reflective surface and directed upward, and then passes through the light emitting portion 233, where it is adjusted to a predetermined light distribution characteristic and enters the display panel 11.

[0022] As shown in FIG. 1B , the elevation angles α1b, α2b, α3b, α4b... are set so that each reflecting surface is at an angle equal to or greater than the critical angle with respect to the incident light, while the relative angles β1b, β2b, β3b, β4b... between the reflecting surface and the connecting surface are set to a constant angle regardless of location, preferably an angle equal to or greater than 90 degrees (βnb≧90°). When manufacturing the reflecting optical element 23b of FIG. 2 by injection molding, setting the relative angle βn to 90 degrees or greater facilitates mold processing of the reflecting surface and the connecting surface. Because each reflecting surface is configured to always be at an angle equal to or greater than the critical angle with respect to the incident light, total reflection is possible without forming a reflective film such as a metal on the light reflecting portion 232. This allows for a low-cost light source device to be realized that includes a reflecting optical element 23b that functions to guide the light in the desired direction and extract it as a planar light having a desired area. On the other hand, in a structure in which an Al reflective film is formed on the reflecting optical element 23b, the angle of incidence on the reflecting surface can be set arbitrarily, increasing the degree of freedom in designing the reflecting optical element 23b.

[0023] 2, the reflective optical element 23b varies the ratio Lrb / Lcb between the length Lrb of the inclined surfaces of the light-reflecting portion 232 projected onto a plane perpendicular to the light-emitting direction of the multiple reflecting surfaces and the length Lcb of the inclined surfaces projected onto a plane perpendicular to the light-emitting direction of the connecting surfaces connecting the reflecting surfaces, as shown in FIG. 1B. Therefore, by appropriately setting the lengths and ratios of the connecting surfaces Lcb1, Lcb2, Lcb3, etc. and the reflecting surfaces Lrb1, Lrb2, Lrb3, etc., the length of the light-emitting portion 233 in the optical axis direction can be freely changed. This makes it possible to realize a light source unit in which the size (surface size) of the light-emitting portion 233 relative to the light-incident portion 231 can be adjusted to the size (surface size) required for a device such as the display panel 11. Furthermore, by appropriately adjusting the ratio Lr / Lc, it is possible to partially strengthen or weaken the reflected light. For example, the ratio Lr / Lc can be adjusted depending on the intensity distribution of light incident on the light-reflecting portion 232. More specifically, in areas of the light reflecting section 232 where the intensity of the incident light is high, the ratio Lr / Lc is reduced, that is, the reflecting surface elevation angle αnb is set at fine intervals, thereby enabling precise control of the light reflection direction and uniform adjustment of the brightness distribution of the light incident on the display panel 11.

[0024] FIG. 3 is a diagram showing a decorative printed unit used in a display device. The display device 1 shown in FIG. 3 is equivalent to the display device shown in FIG. 1A. The display device shown in FIG. 3 has a decorative printed unit 13 provided in an opening 14 of a housing in which the display device is housed. The decorative printed unit 13 includes a decorative printed layer and a transparent member 130. That is, a decorative printed layer or a transparent member 130 having a printed layer laminated thereon is disposed in the direction of emission of image light emitted from the display panel 11. In this embodiment, the image light emitted from the display panel 11 is incident at a predetermined angle with respect to the light incident surface of the decorative printed unit 13. The arrangement of the decorative printed unit 13 differs from the display device shown in FIG. 1A in that the opening 14 may include a transparent plate such as a glass plate or an acrylic plate to support the decorative printed unit 13. In this embodiment, the top of the opening of the housing is the side from which the image light emitted from the display device 1 is emitted. The display device 1 in this embodiment may also be referred to as an image display device or a virtual image display device.

[0025] In this embodiment, the image light emitted from the display device 1 passes through the decorative printed section 13 and is reflected by the transmissive reflecting member 7, which is a projection member, toward the viewer 9. The viewer 9 views the image generated by the display device 1 as a virtual image 8 in front of the viewer 9 through the transmissive reflecting member 7. Meanwhile, unwanted light traveling directly from the display device 1 toward the viewer 9 without passing through the transmissive reflecting member 7 is blocked by the decorative printed section 13. This prevents the viewer 9 from viewing the display device 1 located behind the decorative printed section 13 or on the image light incident side of the decorative printed section 13. In other words, by providing the decorative printed section 13, which transmits the image light and blocks unwanted light, in the opening 14 of the housing, the display device 1 can be mounted on the housing without compromising the design and aesthetic appeal of the housing. The detailed configuration of the decorative printed section 13 will be described later.

[0026] Generally, a decorative print refers to a design material in which, for example, a wood-grain or marble-like pattern (or design) is printed on a substrate such as a resin sheet, as shown in Fig. 4(A). In addition to the above, other patterns include patterns that imitate carbon materials, and patterns that imitate the appearance of leather or cloth, etc. By attaching a decorative print to a substrate such as resin or metal, the design of home appliances and vehicle interior parts can be improved.

[0027] 4(B) is a diagram showing an example of the configuration of the decorative printing unit 13. The decorative printing unit 13 includes a decorative printing layer 131 formed by printing a design (pattern) by a printing method such as gravure printing or screen printing on a transparent member 130 such as a PE (polyethylene) film, a PP (polypropylene) film, or a PC (polycarbonate) film, a clear layer 138 that protects the decorative printing layer 131, and an adhesive layer 139 made of adhesive or pressure-sensitive adhesive disposed below the transparent member 130. The top of the transparent member 130 is the side from which light is emitted, and the bottom of the transparent member is the side from which light is incident.

[0028] The thickness of the decorative printed portion 13 is generally about 0.2 to 0.5 mm. Furthermore, the light transmittance of the decorative printed portion 13, which is typically used as a decorative film for applications such as vehicle interior materials and the surface design of home appliances, is low, at about 1 to 5%. Therefore, as shown in FIG. 4B , if the brightness of the image light incident from below the decorative printed portion 13 is 400 to 500 nits, which is equivalent to that of a typical liquid crystal display or organic EL display, the brightness of the image light emitted from above the decorative printed portion 13 is significantly reduced to at most 25 nits.

[0029] On the other hand, in the embodiment of Figure 3, the light transmittance of the decorative printed portion 13 is very low, at about 1 to 5%, so the brightness of the virtual image 8 generated after passing through the decorative printed portion 13 is significantly reduced. In addition, the transmissive reflective member 7 that reflects the image light is, for example, a glass plate, and its reflectance is low, at about 4 to 30%, so the virtual image tends to be dark. In other words, in a display device that displays an image as a virtual image 8 as in the embodiment of Figure 3, the transmission characteristics of the decorative printed portion 13 are a very important factor in maintaining the brightness required for the virtual image 8 (for example, about 500 nits).

[0030] FIG. 5 is a cross-sectional view showing the internal structure of a decorative printed unit 13 used in a display device according to the present invention. As shown in FIG. 5 , the decorative printed unit 13 according to this embodiment sandwiches a transparent member 130 from both the top and bottom (Y axis), or alternatively, a decorative printed layer 131 is disposed on the top of the transparent member 130 and a decorative printed layer 132 is disposed on the bottom of the transparent member 130. The transparent member 130 may be made of a transparent film or sheet such as PE (polyethylene), PP (polypropylene), or PC (polycarbonate), or may be made of glass or solid resin. The top of the transparent member 130 in FIG. 5 refers to the side from which image light from the display panel 11 exits the transparent member 130, and the bottom of the transparent member 130 refers to the side from which image light from the display panel 11 enters the transparent member 130. The x direction is the left-right direction as seen by the observer 9, the y direction is the vertical direction, or the up-down direction of the transparent member 130, and the z direction is the front-to-back direction as seen by the observer 9, or a direction perpendicular to the up-down direction (y direction) of the transparent member 130.

[0031] In the decorative printing layer 131, portions 1311 where ink for printing a pattern is present and portions 1312 where ink is not present are arranged at equal intervals in the z direction, and the portions 1311 where ink is present and the portions 1312 where ink is not present are the same ratio, i.e., 50% of each other. Similarly, in the decorative printing layer 132, portions 1321 where ink for printing a pattern is present and portions 1322 where ink is not present are arranged at equal intervals, and the portions 1321 where ink is present and the portions 1322 where ink is not present are the same ratio, i.e., 50% of each other. In other words, the transparent member 130 has decorative printing layers 131 and 132 printed with printing ink on both the incident and exit sides of the image light, and the decorative printing layers 131 and 132 have portions where printing ink is present and portions where printing ink is not present alternately at a predetermined pitch. Note that the portions where printing ink is not present may be provided with spaces or may be filled with transparent ink or transparent resin.

[0032] 5, the image portions printed on the decorative printing layers 131 and 132, i.e., the portions 1311 and 1321 where printing ink is present, are offset from each other in the vertical direction, and when the viewer 9 views the decorative printing portion 13 from directly above in the vertical direction, the viewer 9 can recognize the image as a continuous pattern. In other words, when the viewer 9 views the decorative printing portion 13 from directly above, the viewer 9 can recognize the image as a single, continuous pattern. Alternatively, the positions of the decorative printing layer 132 arranged on the light-incident surface of the transparent member 130, in a direction parallel to the plane of the transparent member 130, corresponding to the portions where printing ink is present and the portions where printing ink is not present, are different from the positions of the decorative printing layer 131 arranged on the light-exiting surface of the transparent member 130, in a direction parallel to the plane of the transparent member 130, corresponding to the portions where printing ink is present and the portions where printing ink is not present.

[0033] On the other hand, the portions of the decorative printing layers 131 and 132 that are not the image portions printed thereon, i.e., the portions 1312 and 1322 where no printing ink is present, are also offset in the vertical direction. Here, the image light emitted from the display panel 11 is incident on the decorative printing portion 13 at a predetermined inclination with respect to the horizontal plane, as shown in Fig. 5 . Alternatively, the position of the transparent member 130 corresponding to the portion of the decorative printing layer 131 on the image light emission side of the transparent member 130 where printing ink is present, and the position of the transparent member 130 corresponding to the portion of the decorative printing layer 131 on the image light incidence side of the transparent member 130 where printing ink is present, are offset at an angle tilted by a predetermined angle from the normal direction to the plane of the transparent member 130. Alternatively, a portion 1311 where printing ink is present in the decorative printed layer 131 arranged on the image light exit surface side of the transparent member 130 and a portion 1321 where printing ink is present in the decorative printed layer 132 arranged on the image light incident surface side of the transparent member 130 are arranged at a predetermined angle from the normal direction to the plane of the transparent member 130. Therefore, from the viewpoint of the observer 9, the image light is not blocked by the decorative printed layers 131, 132, and the virtual image 8 can also be viewed. In other words, the decorative printed portion 13 does not reduce the brightness of the virtual image 8 viewed by the observer 9.

[0034] 3, the image light emitted from the image forming unit 10 of the display device 1 is emitted toward the transmissive reflector 7 and therefore travels in front of the viewer 9. On the other hand, unwanted light that travels directly from the display device 1 toward the viewer 9 without passing through the transmissive reflector 7 travels directly upward in the vertical direction (y-axis direction) or behind the viewer 9. Therefore, the printing ink 1311 present in the decorative printing layer 131 and the printing ink 1321 present in the decorative printing layer 132 are arranged so that, as shown in FIG. 5, the image light, i.e., light traveling in front of the viewer 9, passes through both portions 1312 and 1322 where no printing ink is present, and the unwanted light, i.e., light traveling directly upward in the vertical direction or behind the viewer 9, is incident on at least one of the portion 1311 where printing ink is present or the portion 1321 where printing ink is present.

[0035] 5, the ink-containing portions 1311, 1321 and the ink-free portions 1312, 1322 are arranged in the same proportion, but they do not necessarily have to be arranged in the same proportion. That is, it is sufficient that the ink-containing portions 1311, 1321 and the ink-free portions 1312, 1322 are arranged so that the image light entering the decorative printed portion 13 is not blocked by the decorative printed layers 131, 132.

[0036] In FIG. 5 , the ratio of the portions where printing ink is present to the portions where printing ink is not present is the same. On the other hand, as shown in FIG. 6 , the pattern portion of the decorative printing layer 131, i.e., the portion 1311 where printing ink is present, and the portion of the decorative printing layer 131 that is not the pattern portion, i.e., the portion 1312 where printing ink is not present, are alternately arranged in the left-right direction relative to the z direction or the direction of incidence and emission of the image light. However, the area of ​​the portion 1311 where printing ink is present may be large, and the area of ​​the portion 1312 where printing ink is not present may be small. The decorative printing layer 132 may also have the same configuration as the decorative printing layer 131, i.e., the area of ​​the portion 1321 where printing ink is present may be large, and the area of ​​the portion 1322 where printing ink is not present may be small. Also, in FIG. 6 , the decorative printing layer 131 is arranged on the top of the transparent member 130, and the top of the transparent member 130 is the side from which the image light from the display panel 11 is emitted from the transparent member 130. The decorative print layer 132 is disposed on the lower part of the transparent member 130 , and the lower part of the transparent member 130 is the side where the image light from the display panel 11 enters the transparent member 130 .

[0037] As shown in Figure 6, when comparing the lengths in the left-right direction relative to the incident and exit directions of the image light or in the direction perpendicular to the up-down direction of the transparent member 130 (or the z-axis), the ratio between the portion 1311 where printing ink is present and the portion 1312 where printing ink is not present is, for example, approximately 8:2. Therefore, when an observer 9 views the decorative printed unit 13 from directly above in the vertical direction, the area of ​​the pattern portion occupies the majority of the area, and the observer 9 can visually recognize the pattern of the decorative printed unit 13 as a continuous one. Meanwhile, in Figure 6, the decorative printed layer 132 at the bottom of the transparent member 130 is composed of a portion 1321 printed with black or dark ink and a portion 1322 where nothing is printed, and the ratio between the two, i.e., the portion 1321 printed with black or dark ink and the portion 1322 where nothing is printed, is also the same as that of the decorative printed layer 131, for example, approximately 8:2.

[0038] Here, the printing ink 1311 of the decorative printing layer 131 and the printing ink 1321 of the decorative printing layer 132 shown in FIG. 5 have different ink colors depending on the color of the pattern. Therefore, the light transmittance varies depending on the wavelength, and certain wavelengths are transmitted through the portions 1311 and 1321 where the printing ink is present. If a portion of the image light and unwanted light incident on the decorative printing portion 13 is transmitted through the portions 1311 and 1321 where the printing ink is present, the image light transmitted through the portions 1311 and 1321 where the printing ink is present will cause the virtual image 8 to be displayed in a color different from the intended color. Furthermore, the unwanted light transmitted through the portions 1311 and 1321 where the printing ink is present will cause the display device 1 to be visible to the observer 9. To address this problem, as shown in FIG. 6, the printing ink 1321 of the decorative printing layer 132 can be made black or dark, thereby suppressing the influence of the color of the pattern, i.e., the color of the printing ink. In the example of Figure 6, the printing ink 1321 of the decorative printing layer 132 is black or dark in color, but a new black or dark ink layer may be provided between the printing ink 1311 of the decorative printing layer 131 and the transparent member 130.

[0039] 6 , in the decorative printed layer 131, a portion 1312 where no printing ink is present, i.e., a portion with a light transmittance of approximately 100%, and a portion 1322 where nothing is printed, i.e., a portion with a light transmittance of approximately 100%, in the decorative printed layer 132 below the decorative printed portion 13 are arranged according to the angle of incidence of the image light onto the decorative printed portion 13, and the image light passes through the portions 1312 and 1322 of the decorative printed layers 131 and 132 where no printing ink is present, respectively. By arranging the ink-free portions of the upper and lower decorative printed layers 131 and 132 of the transparent member 130 at a predetermined angle on the transparent member 130, from the viewpoint of the observer 9, the image light from the display panel 11 can be prevented from losing light in the decorative printed layers 132 and 131, and a decrease in brightness of the virtual image viewed by the observer 9 can be prevented.

[0040] In addition, unwanted light traveling directly from the display device 1 to the observer 9 is blocked by the portion 1311 where the printing ink of the decorative printing layer 131 is present or the portion 1321 where the printing ink of the decorative printing layer 132 is present, so that the display device 1 cannot be directly viewed by the observer 9.

[0041] In this embodiment, by using black or dark ink for the printing ink 1321 of the decorative printed portion 13, unwanted light traveling directly from the display device 1 to the observer 9 is blocked regardless of the color of the pattern, in other words, the light transmission characteristics of the printing ink 1311 of the decorative printed layer 131, and the display device 1 is not visible to the observer 9. Therefore, by providing the decorative printed portion 13 that transmits image light and blocks unwanted light in the opening of the housing, it is possible to mount the display device 1 on the housing without impairing the design and aesthetic appeal of the housing.

[0042] 7 and 8, the specific shapes of the portions 1311 and 1321 where ink is present and the portions 1312 and 1322 where ink is not present for printing the patterns of the decorative printing layers 131 and 132 will be described. FIGS. 7(1) and 8(1) are views of the decorative printing layers 131 and 132 viewed from the normal direction (y direction) of the plane of the decorative printing portion 13, with the black portions representing the portions 1311 and 1321 where ink is present and the white portions representing the portions 1312 and 1322 where ink is not present. The portions 1312 and 1322 where ink is not present are portions that primarily transmit light, and therefore may also be referred to as openings. The example of FIG. 7 is an example in which the portions 1312 and 1322 (openings) where ink is not present are rectangular, such as rectangular. The example of FIG. 8 is an example in which the portions 1312 and 1322 (openings) where ink is not present are round, such as oval. 7 and 8 show examples in which openings of the same shape are periodically arranged. In this way, by periodically arranging openings of the same shape, it is possible to inexpensively manufacture the decorative print layers 131, 132. Note that, if necessary for other reasons, the shapes of these openings in the decorative print layers 131, 132 do not necessarily have to be completely identical, and the arrangement does not necessarily have to be completely periodic.

[0043] FIG. 7(2) is an enlarged view of one of the ink-free portions or openings 1312 shown in FIG. 7(1). The length of the opening 1312 in the x direction is indicated as x1, and the length in the z direction perpendicular to the x direction is indicated as z1. FIG. 8(2) is an enlarged view of one of the ink-free portions or openings 1312 shown in FIG. 8(1). The length of the opening 1312 in the x direction is indicated as x2, and the length in the z direction perpendicular to the x direction is indicated as z2. The x direction is the left-right direction as seen from the viewer 9, and the z direction is the front-back direction as seen from the viewer 9. As shown in FIGS. 7(2) and 8(2), the shape of the portion 1312 of the decorative printing layer 131 where printing ink is not present is rectangular or round. Furthermore, in the portion 1312 where printing ink is not present, the length parallel to the incident surface through which the image light enters the decorative printing layer 131 is longer than the length perpendicular to the incident surface of the image light.

[0044] The examples of Figures 7 and 8 may be applied to any of the decorative printed units 13 described in Figures 5 and 6. Here, when a light beam emitting image light passes through the openings of the decorative printed layers 131 and 132 of the decorative printed unit 13 at an angle γ with respect to the perpendicular to the plane of the decorative printed unit 13, the effective opening shape of the light beam emitting image light is the shape of the opening of the decorative printed unit 13 projected onto a plane perpendicular to the traveling direction of the light beam forming the virtual image. Therefore, in order to ensure a more symmetrical shape of the effective opening shape of the light beam forming the virtual image, it is desirable to make the length in the z direction longer than the length in the x direction in the opening shapes on the plane of the decorative printed layers 131 and 132 in the examples of Figures 7 and 8. Otherwise, the effective opening would be shorter in the direction corresponding to the z direction of the decorative printed layers 131 and 132 in the plane perpendicular to the traveling direction of the light beam forming the virtual image. Therefore, when the example of FIG. 7(2) is used for the decorative printed portion 13 described in FIGS. 5 and 6, if the light beam forming the virtual image is incident at an angle γ relative to the perpendicular to the plane of the decorative printed layers 131 and 132, it is desirable to satisfy z1 > x1. Furthermore, when the example of FIG. 8(2) is used for the decorative printed layers 131 and 132 described in FIGS. 5 and 6, if the light beam forming the image is incident at an angle γ relative to the perpendicular to the plane of the decorative printed layers 131 and 132, it is desirable to satisfy z2 > x2. By using such a shape, the actual opening shape of the light beam forming the image can be made more symmetrical, thereby maintaining the uniformity of the image quality. Note that, if necessary for other reasons, the relationship between the x-direction length and the z-direction length of the opening shapes in the decorative printed layers 131 and 132 does not necessarily have to satisfy the relationship in the above formula.

[0045] The opening shapes shown in the examples of Figures 7 and 8 may be generated, for example, by various mask processes during or after printing. These opening shapes may be formed using microholes, such as those shown in Figure 9. These opening shapes may also be generated by laser processing, for example. The opening shapes of the decorative printing layers 131, 132 shown in Figures 7 and 8 described above enable virtual image display with better image quality. Furthermore, the opening shapes of the decorative printing layers 131, 132 shown in Figures 7 and 9 allow the decorative printing layers 131, 132 of this embodiment to be manufactured more inexpensively. The display device 1 provided with the decorative printing unit 13 described above can provide a more suitable display technology.

[0046] FIG. 9 is a diagram showing a decorative printed portion having micropores or openings. The decorative printed portion 13 includes a transparent member 130 made of a transparent film or sheet such as a PE (polyethylene) film, a PP (polypropylene) film, or a PC (polycarbonate) film, or a glass material or solid resin. A decorative printed layer 131 having a pattern printed thereon is disposed on the transparent member 130. A clear layer 138 is disposed on the decorative printed layer 131 to protect the decorative printed layer 131. A decorative printed layer 133 having a pattern printed thereon is disposed below the transparent member 130, and an adhesive layer 139 is disposed below the decorative printed layer 133 for adhesion. As described in FIG. 6, by making the decorative printed layer 133 black or a dark color, the influence of the color or pattern of the decorative printed layer 131 can be reduced.

[0047] The decorative printing layers 131, 133 of the decorative printing unit 13 in FIG. 9 are configured to have micropores or openings at predetermined intervals in a direction perpendicular to the up-down direction of the transparent member 130 or in the left-right direction (or z-axis) relative to the emission direction of the image light. Specifically, the decorative printing layers 131, 133 have micropores or openings with a predetermined depth or depth direction arranged at predetermined intervals in a direction parallel to the image light incident on the incident surface side of the decorative printing layers 131, 133. In the y-axis or image light incident / exit direction, the micropores or openings 140 penetrate the decorative printing unit 13 and are approximately parallel or parallel to the optical axis of the image light. In other words, the micropores or openings 140 are arranged at a predetermined angle on the incident surface of the decorative printing layers 131, 133. Note that the micropores 140 may penetrate only the decorative printing layer 131, the transparent member 130, and the decorative printing layer 133, with no holes in the clear layer 138 or adhesive layer 139. Furthermore, the transmittance can be adjusted by the pitch or density of the micropores or openings 140. The pitch or density of the micropores or openings 140 is the number of holes arranged at a predetermined interval. However, instead of arranging them at a predetermined interval, the micropores or openings 140 may be arranged according to the amount of image light passing through. The size of the micropores or openings 140 may also be designed according to the amount of image light passing through. By arranging the micropores or openings 140, the image light is transmitted and light that goes directly toward the viewer is blocked.

[0048] FIG. 10 shows a decorative print unit to be combined with a film. The decorative print unit 13 includes a transparent member 130 made of a transparent film or sheet, such as a PE (polyethylene) film, a PP (polypropylene) film, or a PC (polycarbonate) film, or a glass or solid resin. A decorative print layer 131, on which a pattern (pattern) is printed, is disposed. A clear layer 138 is disposed on the decorative print layer 131 to protect the decorative print layer 131. A control film 141 for adjusting the viewing angle is disposed below the transparent member 130, and an adhesive layer 139 is disposed below the control film 141 for adjusting the viewing angle. Alternatively, the control film 141 for adjusting the viewing angle is disposed between the transparent member 130 and the adhesive layer 139. The control film 141 for adjusting the viewing angle transmits light incident at a predetermined angle and absorbs light incident at angles different from the predetermined angle. The control film 141 for adjusting the viewing angle also includes a black silicone 1411 and a transparent silicone 1412. The black silicone 1411 and the transparent silicone 1412 are alternately arranged at a predetermined pitch in a direction parallel to the image light incident surface or image light exit surface of the transparent member 130, or in the left-right direction relative to the image light incident / exit direction or along the z-axis.

[0049] As shown in FIG. 10 , the black silicone 1411 has a plane that is approximately parallel or parallel to the image light incident on the control film 141. The black silicone 1411 is also arranged at an angle so as to be approximately parallel or parallel to the optical axis of the image light, and the image light passes through the control film 141. That is, the black silicone 1411 is arranged at an angle with respect to the light incident surface of the control film 141. Meanwhile, unwanted light traveling directly from the display device 1 toward the observer 9 is blocked by the black silicone 1411, making the display device 1 invisible to the observer 9. The control film 141 can adjust its transmission characteristics for both the image light and the unwanted light by adjusting the inclination, height, and pitch of the black silicone 1411. Therefore, by providing a decorative printed portion 13 including a control film 141 that transmits image light and blocks unwanted light at an opening in the housing, the display device 1 can be mounted on the housing without compromising the design and aesthetic appeal of the housing.

[0050] FIG. 11 is a diagram showing a decorative print unit to be combined with a polarizing plate. The decorative print unit 13 includes a decorative print layer 131 with a pattern printed thereon, disposed on a transparent member 130 made of a transparent film or sheet such as a PE (polyethylene) film, a PP (polypropylene) film, or a PC (polycarbonate) film, or a glass material or solid resin. A clear layer 138 is disposed on top of the decorative print layer 131 to protect the decorative print layer 131. The decorative print layer 131 is the same as the decorative print layer 131 in FIG. 5. A polarizing plate 142 is disposed below the transparent member 130 via an adhesive layer 139, and another adhesive layer 139 is disposed below the polarizing plate 142. Image light enters the polarizing plate 142, passes through the transparent member 130 and the decorative print layer 131, and exits from the clear layer 138.

[0051] The polarizing plate 142 in FIG. 11 is an absorptive polarizing plate, and the absorption axis angle of the polarizing plate 142 is adjusted so that it is perpendicular to the polarization axis of the image light. The polarizing plate 142 is arranged so that the transmission axis of the polarizing plate 142 is parallel to the polarization axis of the image light. By arranging the polarizing plate 142, half of the external light incident from the outside can be cut, thereby reducing the intensity of stray light generated by internal reflection within the housing. If stray light generated by internal reflection is directed toward the viewer 9, the display device 1 will be visible to the viewer 9, compromising the design and aesthetic appeal of the housing. Therefore, by arranging the decorative printed portion 13 equipped with the polarizing plate 142 at the opening of the housing and cutting half of the external light incident from the outside, the intensity of stray light generated by internal reflection can be reduced, allowing the display device 1 to be mounted in the housing without compromising the design and aesthetic appeal of the housing. Similarly, by providing a polarizing plate 142 for the decorative printed portion 13 described in Figures 5 to 10, it is possible to cut half of the external light entering from the outside and reduce the intensity of stray light generated by internal reflection.

[0052] FIG. 12 is a diagram showing a decorative printed portion combined with a retardation film (1 / 4λ film) and a polarizing plate. The decorative printed portion 13 is a transparent film or transparent sheet such as a PE (polyethylene) film, a PP (polypropylene) film, or a PC (polycarbonate) film, or a transparent member 130 made of glass or solid resin. A decorative printed layer 131 with a pattern (pattern) printed thereon is disposed on the transparent member 130, and a clear layer 138 protecting the decorative printed layer 131 is disposed on the decorative printed layer 131. The decorative printed layer 131 is the same as the decorative printed layer 131 in FIG. 5. A polarizing plate 142 is disposed below the transparent member 130 via an adhesive layer 139, and a retardation film (1 / 4λ) 143 is disposed below the polarizing plate 142 via an adhesive layer 139, and an adhesive layer 139 is disposed below the retardation film 143. That is, an adhesive layer 139, a polarizing plate 142, an adhesive layer 139, a retardation film 143, and an adhesive layer 139 are arranged in this order below the transparent member 130. The polarizing plate 142 is an absorptive polarizing plate, and the absorption axis angle of the polarizing plate 142 is adjusted to be perpendicular to the polarization axis of the image light. By disposing the polarizing plate 142, half of the external light (P-polarized light) incident from the outside can be cut, thereby reducing the intensity of stray light generated by internal reflection. Meanwhile, S-polarized light transmitted through the polarizing plate 142 is converted into circularly polarized light by transmitting through the retardation film 143, and then internally reflected back into the retardation film 143 and converted into P-polarized light. The stray light converted into P-polarized light due to internal reflection is then absorbed by the polarizing plate 142. Therefore, the intensity of stray light generated by internal reflection of external light incident from the outside can be significantly reduced by the polarizing plate 142 and the retardation film 143, making it difficult for the viewer 9 to directly view the display device 1. This allows the display device 1 to be mounted on the housing without impairing the design or aesthetic appeal of the housing. Image light enters the retardation film 143, passes through the polarizing plate 142, the transparent member 130, and the decorative print layer 131, and is emitted from the clear layer 138.

[0053] 13 is a diagram showing a display device 1 provided with a decorative printed portion 13 mounted on a vehicle. Image light from the display device 1, in other words, projection light, is emitted toward a projection area of ​​the windshield 3, which is a projection member, via the decorative printed portion 13. An observer 9 can visually recognize the image light as a virtual image 8.

[0054] FIG. 14 is a diagram illustrating the relationship between a display device 1 equipped with a decorative print unit and a vehicle controller. The display device 1 acquires vehicle information 4 from cameras and various sensors installed in various parts of the vehicle 2. The various sensors, for example, detect various events occurring in the vehicle 2, periodically detect the values ​​of various parameters related to the driving situation, and acquire road and other information from a navigation device. The vehicle information 4 includes, for example, the vehicle 2's speed information, gear information, steering angle information, lamp illumination information, external light information, distance information, infrared information, engine ON / OFF information, camera image information, acceleration gyro information, GPS (Global Positioning System) information, navigation information, vehicle-to-vehicle communication information, and road-to-vehicle communication information. The camera image information includes in-vehicle camera image information and outside-vehicle camera image information. The GPS information includes latitude and longitude as well as current time information. The vehicle information 4 also includes information input by the driver. With respect to the vehicle 2 and the driver, the horizontal direction x is the left-right direction, the lateral direction of the vehicle, or the width direction of the vehicle, the vertical direction z is the up-down direction or longitudinal direction of the vehicle, and the horizontal direction y, which is perpendicular to the lateral direction of the vehicle, is the front-rear direction of the vehicle or the direction of travel of the vehicle. The display device 1 may also be called a virtual image display device.

[0055] Based on such vehicle information 4, the display device 1 projects / emits image light onto a display area 5 of the windshield 3. As a result, the display device 1 superimposes a virtual image corresponding to the displayed image onto the scenery, allowing the driver (from the driver's viewpoint) of the vehicle 2 to view it. The projection unit that projects the image light may be a projection member such as a combiner.

[0056] The display device 1 is connected to a controller 100 of the vehicle 2 via an information transmission path, and the display device 1 and the controller 100 can communicate with each other. The controller 100 of the vehicle 2 is, for example, an ECU (Electronic Control Unit). The display device 1 and the controller 100 of the vehicle 2 communicate with each other via the information transmission path, for example, a CAN (Controller Area Network). Note that the display device 1 and the controller 100 of the vehicle 2 may also communicate with each other via an in-vehicle Ethernet or the like via the information transmission path.

[0057] For example, when all information including video information is transmitted over a single information transmission path, the connection between the controller 100 (a source of video information, etc.) on the vehicle 2 side and the display device 1 (in other words, the connection form of the information transmission path) may be FPD-Link III, GMSL (Gigabit Multimedia Serial Link), or the like.

[0058] The controller 100 controls the vehicle 2 based on the input and output of data, and an in-vehicle system is configured by being connected to the display device 1. The in-vehicle system is a system in which the controller 100 can control the vehicle 2 using vehicle information 4.

[0059] The display device 1 can acquire vehicle information data based on a communication protocol compatible with a CAN (Controller Area Network) interface, a LIN (Local Interconnect Network) interface, etc. The controller 100 of the vehicle 2 can also acquire data in a similar manner.

[0060] As shown in Fig. 15, the vehicle information 4 is acquired using devices such as cameras and various sensors connected to the controller 100 or the control device. Note that the various devices in Fig. 15 can be deleted, or other types of devices can be added or replaced with other types of devices as appropriate. As an example, the controller 100 of the vehicle 2 may have a control function for the display device 1.

[0061] The vehicle speed sensor 901 detects the speed of the vehicle 2 and is used to generate speed information, which is the detection result. The shift position sensor 902 detects the current gear and is used to generate gear information, which is the detection result. The steering wheel angle sensor 903 detects the current steering wheel angle and is used to generate steering wheel angle information, which is the detection result. The headlight sensor 904 detects whether the headlights are on or off and is used to generate lamp illumination information, which is the detection result.

[0062] The illuminance sensor 905 and chromaticity sensor 906 detect external light from the vehicle 2 and are used to generate external light information that serves as the detection result. The distance measurement sensor 907 detects the distance between the vehicle 2 and an external object or the distance between two external objects and is used to generate distance information that serves as the detection result. The infrared sensor 908 detects the presence or absence of an object in the vicinity of the vehicle 2 and the distance thereto and is used to generate infrared information that serves as the detection result. The engine start sensor 909 detects whether the engine is on or off and is used to generate on / off information that serves as the detection result.

[0063] The acceleration sensor 912 and the gyro sensor 913 detect the acceleration and angular velocity of the vehicle 2 and are used to generate acceleration gyro information that indicates the attitude and behavior of the vehicle 2 .

[0064] The temperature sensor 914 detects the temperature inside and outside the vehicle and is used to generate temperature information representing the detection results.

[0065] For example, if the display device 1 is housed in the dashboard of the vehicle 2, the temperature sensor 914 may be used to detect the temperature inside the dashboard. If a temperature that may affect the operation of the display device 1 is detected, the display device 1 may stop operating. Here, the temperature sensor 914 may be disposed inside the dashboard, as an example. However, the temperature sensor 914 may also be disposed in another location where the temperature may be similar to that inside the dashboard.

[0066] Furthermore, when the display device 1 is not housed in the dashboard, such as on the dashboard, the temperature sensor 914 may be used to detect the temperature in the vicinity of where the display device 1 is installed. If a temperature that may affect the operation of the display device 1 due to direct sunlight or the like is detected, the display device 1 may stop operating. Here, the temperature sensor 914 may be disposed on the dashboard, as an example. The temperature sensor 914 may also be disposed outside the vehicle, assuming that the temperature in the vicinity of the display device 1 and the temperature outside the vehicle are similar.

[0067] The road-to-vehicle communication wireless transceiver 915 generates road-to-vehicle communication information through road-to-vehicle communication between the vehicle 2 and roads, signs, traffic lights, etc. The vehicle-to-vehicle communication wireless transceiver 916 generates vehicle-to-vehicle communication information through vehicle-to-vehicle communication between the vehicle 2 and other surrounding vehicles. The mobile terminal-to-vehicle communication wired and wireless communication unit 917 is a device that acquires information through wired communication or wireless communication from devices (e.g., Wi-Fi devices) connected to an LTE (Long Term Evolution) network. The controller 100 or the control device can acquire information transmitted and received over the LTE network via the mobile terminal-to-vehicle communication wired and wireless communication unit 917.

[0068] The in-vehicle camera 919 and the exterior camera 920 capture images of the interior and exterior of the vehicle and are used to generate in-vehicle camera image information and exterior camera image information. Specifically, the in-vehicle camera 919 is, for example, a camera for a DMS (Driver Monitoring System) that captures the driver's posture, eye position, movement, etc. In this case, by analyzing the captured images, the driver's fatigue state, line of sight position, etc. can be ascertained.

[0069] On the other hand, the exterior camera 920 captures images of the surroundings, such as the area in front of and behind the vehicle 2. In this case, by analyzing the captured images, it becomes possible to determine the presence or absence of obstacles such as other vehicles or people in the vicinity, buildings, topography, road conditions such as rain, snow, ice, and unevenness, road signs, etc. The exterior camera 920 also includes, for example, a drive recorder that records images of the situation while driving.

[0070] The GPS receiver 921 generates GPS information by receiving GPS signals from GPS satellites. For example, the current time, latitude, and longitude can be acquired by the GPS receiver 921. The VICS (Vehicle Information and Communication System, registered trademark) receiver 922 generates VICS information by receiving VICS signals. The GPS receiver 921 and the VICS receiver 922 may be provided as part of a navigation system.

[0071] The voice of the driver is input to the voice input device 918, which is used to generate voice information. By uttering a voice, the driver can input operation details via the voice input device 918. The vehicle operation switch 911 is used to generate information on the driver's operation of the steering switch and the like.

[0072] An in-vehicle camera 919 captures images of the interior of the vehicle. An exterior camera 920 captures images of the exterior of the vehicle. A GPS receiver 921 receives data from the GPS and transmits it to the controller 100. A VICS receiving and transmitting function is also provided.

[0073] 16 and 17 are functional block diagrams showing an example of the configuration of the main control section of a display device provided with a decorative printing section. The sections in Fig. 16 and 17 mainly control the display of projected images on the display device 1.

[0074] 16 , the display device 1 includes, for example, a microcontroller (MCU) 1010 mounted on a wiring board or the like, a non-volatile memory 1011, a volatile memory 1012, an image processing unit 1013, a communication processing unit 1014, a display driver 1021, and a light source driving unit 1022. In the example of FIG. 16 , the communication processing unit 1014 receives and transmits main vehicle information 4, but may also function as a control unit of the display device 1. The image processing unit 1013 receives image information or image data generated by the image generation unit 910 of the controller 100 of the vehicle 2. The image processing unit 1013 does not generate images, but processes images received from the vehicle 2. The processing of the image processing unit 1013 includes image distortion correction, conversion (e.g., decoding), and the like.

[0075] 17 , similarly to the case of FIG. 16 , the device includes a microcontroller (MCU) 1010, a non-volatile memory 1011, a volatile memory 1012, a communication processing unit 1014, an image processing unit 1015, a display driver 1021, and a light source driving unit 1022, all mounted on a wiring board. However, in the example of FIG. 17 , the image processing unit 1015 has the function of the image generation unit 910, and generates image information using acquired information (e.g., vehicle information 4) instead of receiving image information. The image processing unit 1015 can also perform processes such as distortion correction and conversion on the generated image information.

[0076] As is widely known, the MCU 1010 includes a processor such as a CPU (Central Processing Unit), memory, and various peripheral functions. Therefore, each block except for the MCU 1010 may be mounted within the MCU 1010 as appropriate. Furthermore, the display device 1 is not limited to being implemented using the MCU 1010, but may be implemented using an ECU or other semiconductor devices. The control structures shown in FIGS. 16 and 17 may be, for example, a control unit mounted within the housing of the display device 1, or a control unit mounted outside the housing.

[0077] 16 , the MCU 1010 receives video information via, for example, FPD-Link III or GMSL via the communication processing unit 1014. The MCU 1010 may perform processing such as distortion correction and conversion on the received video information as a function of the video processing unit 1013. The video processing unit 1013 is mainly realized by the CPU of the MCU 1010 reading and executing a program stored in the non-volatile memory 1011 or the volatile memory 1012.

[0078] 16 , the MCU 1010 receives the vehicle information 4 via the communication processing unit 1014, for example, via the CAN or in-vehicle Ethernet. The MCU 1010 can generate video data and the like based on the vehicle information 4 and the like, as a function of the video processing unit 1015. The video processing unit 1015 is mainly realized by the CPU of the MCU 1010 reading and executing a program stored in the non-volatile memory 1011 or the volatile memory 1012.

[0079] That is, the image processing unit (1013, 1015) processes image data that determines the display content of the display image to be projected onto the projection member based on the acquired information. The display driver 1021 drives each display element (pixel) included in the display panel 11 based on the image data. As a result, the image forming unit 10 creates and displays an image to be projected onto the display area 5 based on the image data.

[0080] 13, distortion correction corrects image distortion caused by the curvature of windshield 3 when an image from display device 1 is projected onto display area 5. Display driver 1021 then drives each display element (pixel) included in display panel 11 based on the corrected image data. As a result, image forming unit 10 creates and displays an image to be projected onto display area 5 based on the corrected image data.

[0081] Furthermore, the light source driving unit 1022 can adjust the light source, and adjusts the brightness of the light source 20 in the image forming unit or the PGU 110. Based on the vehicle information 4 received via the communication processing unit 1014, the light source 20 is controlled using the light source driving unit 1022, which is a driver used to drive the light source.

[0082] Furthermore, the display device 1 may protect the display panel 11 based on external light information from the illuminance sensor 905. That is, in order to prevent the display panel 11 from being burned by sunlight shining on it, the display device 1 may perform an operation to protect the panel from sunlight according to the value of the illuminance sensor 905. More specifically, when the intensity of external light or sunlight acquired by the illuminance sensor 905 is strong and there is a risk of the display panel 11 being burned, the display device 1 may reduce the brightness of the light source 20 in the image forming unit 10 and suppress the amount of light from the light source 20 that is incident on the display panel 11, thereby suppressing a rise in temperature of the display panel 11.

[0083] The non-volatile memory 1011 mainly stores in advance programs executed by the CPU in the MCU 1010, setting parameters used in the processing of each unit in the MCU 1010, specified audio data, video data, and the like.

[0084] The volatile memory 1012 mainly stores acquired information and various data used in the processing of each unit in the MCU 1010. The communication processing unit 1014 is a device equipped with a communication interface, and communicates with the outside of the display device 1 based on a communication protocol such as CAN or LIN.

[0085] 16 and 17 may be implemented as a dedicated circuit such as a field programmable gate array (FPGA) as appropriate. In this embodiment, the configuration includes a nonvolatile memory 1011 and a volatile memory 1012, but the above processing may be performed by a single memory.

[0086] Although the embodiments have been described above, the present invention is not limited to the above-described embodiments and includes various modifications and equivalent configurations within the spirit of the appended claims. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to those including all of the described configurations. Furthermore, for example, other configurations may be added, deleted, or replaced with part of the configuration of the embodiments.

[0087] By placing a decorative printed part on a display device, the display device cannot be seen by the viewer, and the design of the product is not compromised. By providing micro-holes or openings in the decorative printed part, light that is directed directly toward the viewer is blocked. When combined with a polarizing plate and a retardation film, the decorative printed part can suppress the intensity of stray light generated by internal reflection, significantly reducing stray light generated by the incidence of external light.

[0088] The technology according to this embodiment uses a decorative printed portion that transmits image light and blocks unwanted light traveling directly from the display device to the viewer, making the display device less visible to the viewer without compromising the design and aesthetic appeal of the housing. Furthermore, the intensity of stray light generated by internal reflection can be suppressed, significantly reducing stray light caused by external light incidence. The technology according to this embodiment can provide the viewer with a practical, high-quality display device. This contributes to the "9 Sustainable Development Goals (SDGs)" advocated by the United Nations, "Build resilient infrastructure, promote inclusive and sustainable industrialization, and foster innovation."

[0089] REFERENCE SIGNS LIST 1 display device 11 display panel 12 light source device 13 decorative printing unit

Claims

1. A display device comprising: a display panel capable of emitting image light to a projection member; and a light source device that emits light to the display panel, wherein a transparent member having a decorative printed layer laminated thereon is arranged in the emission direction of the image light emitted from the display panel, and the image light is reflected by the projection member, causing an image generated by the display panel to be viewed as a virtual image.

2. A display device as described in claim 1, wherein the decorative printed layer transmits the image light emitted from the display panel toward the front of the observer and blocks unwanted light emitted from the display panel directly above in the vertical direction or toward the rear of the observer, or the decorative printed layer transmits the image light emitted from the display panel toward the projection member and blocks unwanted light emitted from the display panel toward the observer.

3. A display device according to claim 1, wherein the decorative print layer is formed so that areas where printing ink is present and areas where printing ink is not present are alternately present at a predetermined pitch.

4. A display device as described in claim 1, wherein the transparent member has a decorative print layer printed with printing ink on both the incident side of the transparent member where the image light enters and the exit side of the image light.

5. A display device as described in claim 3, wherein the positions in a direction parallel to the plane of the transparent member corresponding to the portions of a printing layer arranged on the light-incident surface of the transparent member where printing ink is present and the portions of the printing layer arranged on the light-exiting surface of the transparent member are different from the positions in a direction parallel to the plane of the transparent member corresponding to the portions of a decorative printing layer arranged on the light-exiting surface of the transparent member where printing ink is present and the portions of the decorative printing layer arranged on the light-exiting surface of the transparent member where printing ink is present and the portions of the decorative printing layer arranged on the light-exiting surface of the transparent member.

6. A display device as described in claim 3, wherein a portion of the decorative printing layer arranged on the emission surface side of the transparent member where the image light is emitted and a portion of the decorative printing layer arranged on the incidence surface side of the transparent member where the printing ink is present are arranged so as to be offset at an angle inclined at a predetermined angle from the normal direction of the plane of the transparent member.

7. A display device according to claim 3, wherein the decorative print layer has a portion where printing ink is present and a portion where printing ink is not present, the portions being different in size.

8. A display device according to claim 3, wherein the decorative print layer has a rectangular or round shape in a portion where the printing ink is not present.

9. A display device as described in claim 8, wherein the length of the portion where the printing ink is not present in a direction parallel to the incident surface through which the image light is incident on the decorative printing layer is longer than the length in a direction perpendicular to the incident surface of the image light.

10. A display device according to claim 1, wherein the decorative print layer has micropores or openings arranged at predetermined intervals and having a depth in a direction parallel to the image light.

11. A display device as described in claim 1, wherein a control film is arranged on the incident surface side of the transparent member where the image light is incident, and the decorative printing layer is arranged on the exit surface side of the transparent member where the image light is emitted.

12. A display device according to claim 11, wherein the control film comprises black silicone and transparent silicone, and the black silicone and the transparent silicone alternate at a predetermined pitch in a direction parallel to the plane of the transparent member.

13. A display device according to claim 12, wherein the black silicone has a flat surface that is approximately parallel to the image light.

14. A display device as described in claim 1, wherein a polarizing plate is provided on the incident surface side of the transparent member where the image light is incident, and a decorative printing layer is arranged on the exit surface side of the transparent member where the image light is emitted, in which areas where printing ink is present and areas where printing ink is not present are alternately present at a predetermined pitch.

15. A display device according to claim 14, wherein the polarizing plate is an absorptive polarizing plate, and is arranged so that the transmission axis of the polarizing plate is parallel to the polarization axis of the image light.

16. The display device according to claim 14, wherein a retardation film is provided on the polarizing plate on a side on which the image light is incident.

17. A display device according to claim 1, wherein a clear layer for protecting the decorative print layer is provided on the side of the decorative print layer from which the image light is emitted.

Images