Display device and head-up display

Abstract

To provide a display device and a head-up display capable of suppressing deterioration in display quality.SOLUTION: The display device 1 includes a backlight 30, a first liquid crystal display panel 10 on which direct light from the backlight is incident, and a second liquid crystal display panel 20 which is overlapped with the first liquid crystal display panel with a gap S provided between them and on which transmitted light of the first liquid crystal display panel is incident. The first liquid crystal display panel includes a display area AA1. The second liquid crystal display panel includes a display area AA2 and a non-display area NA2. The display area of the first liquid crystal display panel and the non-display area of the second liquid crystal display panel overlap each other when viewed from at least one direction in which the first liquid crystal display panel and the second liquid crystal display panel overlap each other. At least a liquid crystal layer, a polarizing plate, and a color filter are provided in the display region of the first liquid crystal display panel. At least the liquid crystal layer and the polarizing plate are provided in the non-display region of the second liquid crystal display panel, and the color filter is not provided.SELECTED DRAWING: Figure 17

Description

[Technical Field]

[0001] The present invention relates to a display device and a head-up display. [Background technology]

[0002] BACKGROUND ART A head-up display (HUD) is known that projects an image onto a light-transmitting member such as glass, and allows an observer to visually recognize the image reflected by the light-transmitting member as a virtual image (for example, Patent Document 1).

[0003] In a HUD, the spatial position of the virtual image viewed by the observer is determined by the relative positions of the display panel, the reflecting member, and the observer's viewpoint. Specifically, the greater the distance between the display panel and the reflecting member, the greater the distance from the observer's viewpoint to the virtual image, and the closer the distance between the display panel and the reflecting member, the closer the distance from the observer's viewpoint to the virtual image. In Patent Document 1, multiple display panels are stacked at a distance from each other, and different content is displayed on each display panel, thereby varying the distance from the observer's viewpoint to the virtual image of each content. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-168230 Summary of the Invention [Problem to be solved by the invention]

[0005] In the above-described conventional technology, the display areas of the display panels are arranged so as not to overlap in the viewer's line of sight, and the areas other than the display areas are transparent. In such a configuration, for example, it is conceivable to arrange identical display panels one on top of the other, and not control the alignment of the liquid crystal layer in the areas other than the display areas of each display panel. In this case, for example, in the display area of ​​the second display panel that overlaps the area other than the display area of ​​the first display panel, the chromaticity of the image displayed in the display area of ​​the second display panel overlapping the area other than the display area of ​​the first display panel changes due to light passing through the pixels and color filters provided in the area other than the display area of ​​the first display panel, resulting in a decrease in brightness, and thus a decrease in display quality.

[0006] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a display device and a head-up display that can suppress degradation of display quality. [Means for solving the problem]

[0007] A display device according to one embodiment of the present disclosure comprises a backlight, a first liquid crystal display panel onto which direct light from the backlight is incident, and a second liquid crystal display panel overlapping the first liquid crystal display panel with a gap therebetween and onto which transmitted light from the first liquid crystal display panel is incident, wherein the first liquid crystal display panel includes a display area for displaying images, and the second liquid crystal display panel includes a display area for displaying images and a non-display area for not displaying images, and when viewed from at least one direction in which the first liquid crystal display panel and the second liquid crystal display panel overlap, the display area of ​​the first liquid crystal display panel is provided with at least a liquid crystal layer, a polarizer, and a color filter, and the non-display area of ​​the second liquid crystal display panel is provided with at least a liquid crystal layer and a polarizer, but no color filter.

[0008] A head-up display according to one embodiment of the present disclosure is a head-up display that allows an observer to view an image reflected by a translucent member as a virtual image by superimposing the image on a real image that has passed through a translucent member that transmits and reflects incident light, and includes the display device described above and an enlarging optical system that enlarges the image displayed on the display device and projects it onto the translucent member, wherein the polarizing plate provided on the first liquid crystal display panel and the polarizing plate provided on the second liquid crystal display panel are each arranged so that their transmission axes are perpendicular to each other with respect to the incident light, and the liquid crystal layer provided on the first liquid crystal display panel and the liquid crystal layer provided on the second liquid crystal display panel are each initially oriented so as to maximize their transmittance. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram of a head-up display showing an application example of a display device according to an embodiment. [Figure 2A] FIG. 2A is a schematic diagram showing the basic configuration of a HUD. [Figure 2B] FIG. 2B is a schematic diagram illustrating an equivalent configuration of the HUD shown in FIG. 2A. [Figure 3] FIG. 3 is a diagram showing the relationship between the distance a between the panel and the lens and the virtual distance VID between the viewpoint and the virtual image. [Figure 4] FIG. 4 is a schematic diagram showing an equivalent configuration of a HUD. [Figure 5A] FIG. 5A is a schematic circuit diagram showing the main configuration of the first liquid crystal display panel. [Figure 5B] FIG. 5B is a schematic circuit diagram showing the main configuration of the second liquid crystal display panel. [Figure 6A] FIG. 6A is a schematic cross-sectional view of the display area of ​​the first liquid crystal display panel. [Figure 6B] FIG. 6B is a schematic cross-sectional view of the display area of ​​the second liquid crystal display panel. [Figure 7A] FIG. 7A is a schematic cross-sectional view of the non-display area of ​​the first liquid crystal display panel. [Figure 7B] FIG. 7B is a schematic cross-sectional view of the non-display area of ​​the second liquid crystal display panel. [Figure 8] FIG. 8 is a diagram showing a first example of a display mode of the first image. [Figure 9] FIG. 9 is a diagram showing a first example of a display mode of the second image. [Figure 10] FIG. 10 is a cross-sectional view of the display device according to the embodiment taken along the line AA in FIGS. 8 and 9. In FIG. [Figure 11] FIG. 11 is a diagram showing a first example of a virtual image visually recognized by an observer. [Figure 12] FIG. 12 is a diagram showing a second example of the display mode of the first image. [Figure 13] FIG. 13 is a diagram showing a second example of the display mode of the second image. [Figure 14] FIG. 14 is a diagram showing a second example of a virtual image visually recognized by an observer. [Figure 15] FIG. 15 is a diagram showing a third example of the display mode of the first image. [Figure 16] FIG. 16 is a diagram showing a third example of the display mode of the second image. [Figure 17] FIG. 17 is a cross-sectional view of the display device according to the embodiment taken along the arrow BB shown in FIGS. [Figure 18] FIG. 18 is a diagram showing a third example of a virtual image visually recognized by an observer. [Figure 19] FIG. 19 is a schematic diagram of a HUD showing an application example of a display device according to a first modified example of the embodiment. [Figure 20] FIG. 20 is a schematic diagram of a HUD showing an application example of a display device according to a second modification of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Modes (embodiments) for carrying out the present disclosure will be described in detail with reference to the drawings. Note that the present disclosure is not limited to the contents described in the following embodiments. Furthermore, the components described below include those that can be easily imagined by a person skilled in the art and those that are substantially identical. Furthermore, the components described below can be combined as appropriate. Furthermore, the disclosure is merely an example, and appropriate modifications that a person skilled in the art can easily conceive while maintaining the gist of the disclosure are naturally included within the scope of the present disclosure. Furthermore, for clarity of explanation, the drawings may schematically depict the width, thickness, shape, etc. of each part compared to the actual embodiment. However, these are merely examples and are not intended to limit the interpretation of the present disclosure. Furthermore, in this specification and each figure, elements similar to those described above with reference to the previous figures may be designated by the same reference numerals, and detailed descriptions may be omitted as appropriate.

[0011] 1 is a schematic diagram of a head-up display showing an application example of a display device according to an embodiment. The head-up display (HUD, hereinafter also simply referred to as "HUD") 100 includes a display device 1 and a magnifying optical system 2 that magnifies an image displayed on the display device 1 and projects the magnified image onto a light-transmitting member FG.

[0012] The light-transmitting member FG is a light-transmitting member such as glass or resin. Examples of the light-transmitting member FG include a vehicle windshield and a combiner. The light-transmitting member FG is not limited to a vehicle windshield or a combiner as long as it transmits and reflects incident light.

[0013] A lens is an example of the magnifying optical system 2. However, the present invention is not limited to this, and one magnifying optical system 2 may be configured with a plurality of optical members such as a plane mirror or a concave mirror.

[0014] The display device 1 includes, as its main components, a first liquid crystal display panel 10 for displaying a first image, a second liquid crystal display panel 20 for displaying a second image, and a backlight 30.

[0015] The backlight 30 emits planar light (light L) toward the first liquid crystal display panel 10. As indicated by the solid arrows in FIG. 1, the light L emitted from the backlight 30 passes through the first liquid crystal display panel 10, the second liquid crystal display panel 20, and the magnifying optical system 2 in that order, and is reflected by the light-transmitting member FG before reaching the viewpoint of the observer OB.

[0016] The first liquid crystal display panel 10 and the second liquid crystal display panel 20 overlap in the optical axis direction of the magnifying optical system. In other words, the first liquid crystal display panel 10 and the second liquid crystal display panel 20 overlap in the line of sight direction of the display device 1 reflected by the light-transmitting member FG as viewed from the viewpoint of the observer OB. As a result, the position at which the image of the first liquid crystal display panel 10 reflected by the light-transmitting member FG is viewed by the observer OB and the position at which the image of the second liquid crystal display panel 20 reflected by the light-transmitting member FG is viewed by the observer OB coincide in the direction indicated by the dashed arrow in FIG. 1 .

[0017] In the following description, the image displayed on the first liquid crystal display panel 10 will also be referred to as the "first image," and the image displayed on the second liquid crystal display panel 20 will also be referred to as the "second image." Furthermore, the image of the first image reflected by the light-transmitting member FG and viewed by the observer OB will also be referred to as the "virtual image VIR," and the image of the second image reflected by the light-transmitting member FG and viewed by the observer OB will also be referred to as the "virtual image VIF."

[0018] In the following description, the virtual distance from the viewpoint of the observer OB to the virtual image VIR of the first image and the virtual image VIF of the second image reflected by the light-transmitting member FG is also simply referred to as the “virtual distance.” Furthermore, the virtual positions of the virtual image VIR of the first image and the virtual image VIF of the second image reflected by the light-transmitting member FG are also simply referred to as the “virtual position.”

[0019] In this disclosure, the "optical axis of the magnifying optical system" does not refer to the individual optical axis of each optical element when the magnifying optical system 2 is composed of multiple optical elements, but rather refers to the optical axis that passes through a single magnifying optical system 2 composed of multiple optical elements and enters the second liquid crystal display panel 20.

[0020] 1, the first liquid crystal display panel 10 and the second liquid crystal display panel 20 are arranged substantially parallel to a plane (XY plane) perpendicular to the optical axis of the magnifying optical system 2. As a result, a virtual image VIR of the first image and a virtual image VIF of the second image viewed by the observer OB are viewed by the observer OB on a virtual plane (VX-VY plane) substantially parallel to the direction indicated by the dashed arrow in FIG.

[0021] 1, the distance from the viewpoint of the observer OB to the first image displayed on the first liquid crystal display panel 10 is greater than the distance from the viewpoint of the observer OB to the second image displayed on the second liquid crystal display panel 20. As a result, the virtual image VIR of the first image displayed on the first liquid crystal display panel 10 is perceived by the observer OB at a position farther away in the direction indicated by the dashed arrow in FIG. 1 than the virtual image VIF of the second image displayed on the second liquid crystal display panel 20. In other words, the virtual image VIR of the first image displayed on the first liquid crystal display panel 10 is perceived as being further behind the virtual image VIF of the second image displayed on the second liquid crystal display panel 20.

[0022] The relative positional relationship between the virtual images VIR and VIF visually recognized by the observer OB in the HUD 100 will be described below.

[0023] Figure 2A is a schematic diagram showing the basic configuration of a HUD, and Figure 2B is a schematic diagram showing an equivalent configuration of the HUD shown in Figure 2A.

[0024] The eye box EB shown in Fig. 2A indicates the range in which the virtual image VI can be viewed by the observer OB. As shown in Fig. 2B, when the lens O and liquid crystal display panel D of the HUD shown in Fig. 2A are aligned in the line of sight of the observer OB, the distance a (mm) from the center line of the liquid crystal display panel D to the center line of the lens O, the virtual distance b (mm) from the virtual image VI to the center line of the lens O, and the focal length f (mm) of the lens O have the relationship shown in the following formula (1). The distance a from the liquid crystal display panel D to the center line of the lens O is set to be less than the focal length f of the lens O (f>a).

[0025]

number

[0026] The virtual distance VID (mm) from the viewpoint of observer OB to virtual image VI is expressed by the following equation (2) using the distance e from the center line of lens O to the viewpoint of observer OB. Figure 3 is a diagram showing the relationship between the distance a between the panel and lens and the virtual distance VID between the viewpoint and virtual image.

[0027]

number

[0028] 3, the longer the distance a from the liquid crystal display panel D to the center line of the lens O, the farther the virtual distance VID from the viewpoint of the observer OB to the virtual image VI. Also, the closer the distance a from the liquid crystal display panel D to the center line of the lens O is to the focal length f, the greater the amount of change in the virtual distance VID from the viewpoint of the observer OB to the virtual image VI with respect to a change in the distance a.

[0029] Fig. 4 is a schematic diagram showing an equivalent configuration of a HUD. As described above, in the schematic configuration of the HUD 100 shown in Fig. 1, the first liquid crystal display panel 10 is disposed farther from the magnifying optical system 2 than the second liquid crystal display panel 20 in the direction (Z direction) perpendicular to the optical axis of the magnifying optical system 2, in other words, the XY plane perpendicular to the optical axis of the magnifying optical system 2. Specifically, in the equivalent configuration of the HUD 100 shown in Fig. 4, the distance a1 from the first liquid crystal display panel 10 to the center line of the lens O (magnifying optical system 2) is greater than the distance a2 from the second liquid crystal display panel 20 to the center line of the lens O (magnifying optical system 2) (a1>a2).

[0030] A virtual distance VID1 from the viewpoint of the observer OB to the virtual image VIR of the first image displayed on the first liquid crystal display panel 10 corresponds to a distance a1 from the first liquid crystal display panel 10 to the center line of the lens O (magnifying optical system 2). A virtual distance VID2 from the viewpoint of the observer OB to the virtual image VIF of the second image displayed on the second liquid crystal display panel 20 corresponds to a distance a2 from the second liquid crystal display panel 20 to the center line of the lens O (magnifying optical system 2). Therefore, in the equivalent configuration of the HUD 100 shown in FIG. 4, the virtual distance VID1 from the viewpoint of the observer OB to the virtual image VIR of the first image displayed on the first liquid crystal display panel 10 is greater than the virtual distance VID2 from the viewpoint of the observer OB to the virtual image VIF of the second image displayed on the second liquid crystal display panel 20 (VID1>VID2).

[0031] As a result, the virtual image VIR of the first image displayed on the first liquid crystal display panel 10 is viewed at a virtual position farther from the observer OB than the virtual image VIF of the second image displayed on the second liquid crystal display panel 20.

[0032] Fig. 5A is a schematic circuit diagram showing the main components of the first liquid crystal display panel. Fig. 5B is a schematic circuit diagram showing the main components of the second liquid crystal display panel. The first liquid crystal display panel 10 and the second liquid crystal display panel 20 are transmissive liquid crystal display panels, and have, for example, a plurality of pixels Pix driven by an active matrix system.

[0033] The first liquid crystal display panel 10 includes a display area AA1, a non-display area NA1, a signal output circuit 16, and a scanning circuit 17. The display area AA1 is an area in the first liquid crystal display panel 10 where a first image is displayed. The non-display area NA1 is an area in the first liquid crystal display panel 10 where no image is displayed.

[0034] The second liquid crystal display panel 20 includes a display area AA2, a non-display area NA2, a signal output circuit 26, and a scanning circuit 27. The display area AA2 is an area in the second liquid crystal display panel 20 where a second image is displayed. The non-display area NA2 is an area in the second liquid crystal display panel 20 where no image is displayed.

[0035] A plurality of pixels Pix are arranged in a matrix in the display area AA1 of the first liquid crystal display panel 10 and the display area AA2 of the second liquid crystal display panel 20. Each pixel Pix includes a pixel transistor Tr and two electrodes. Fig. 6A is a schematic cross-sectional view of the display area of ​​the first liquid crystal display panel. Fig. 6B is a schematic cross-sectional view of the display area of ​​the second liquid crystal display panel.

[0036] The display area AA1 of the first liquid crystal display panel 10 is an area that overlaps with the second liquid crystal display panel 20, and is an area in which the liquid crystal layer 3 and the polarizing plate 16 are provided.

[0037] The display area AA2 of the second liquid crystal display panel 20 is an area that overlaps with the first liquid crystal display panel 10, and is an area in which the liquid crystal layer 3 and the polarizer 26 are provided.

[0038] The display area AA1 of the first liquid crystal display panel 10 and the display area AA2 of the second liquid crystal display panel 20 are areas capable of displaying a color image made up of a plurality of colors.

[0039] The first liquid crystal display panel 10 has a first substrate 11, a second substrate 12, and a liquid crystal layer 3 sealed between the first substrate 11 and the second substrate 12. The first substrate 11 and the second substrate 12 are light-transmitting glass substrates.

[0040] In the display area AA1 of the first liquid crystal display panel 10, a pixel electrode PX is laminated on the liquid crystal layer 3 side of the first substrate 11, an insulating layer 13 is laminated on the liquid crystal layer 3 side of the pixel electrode PX, and a polarizer 16 is attached to the outside of the first substrate 11.

[0041] In the display area AA1 of the first liquid crystal display panel 10, a common electrode COML is laminated on the liquid crystal layer 3 side of the second substrate 12, and an insulating layer 14 is laminated on the common electrode COML on the liquid crystal layer 3 side. In the display area AA1 of the first liquid crystal display panel 10, a color filter 15 is laminated on the liquid crystal layer 3 side of the insulating layer 14.

[0042] The second liquid crystal display panel 20 has a first substrate 21, a second substrate 22, and a liquid crystal layer 3 sealed between the first substrate 21 and the second substrate 22. The first substrate 21 and the second substrate 22 are light-transmitting glass substrates.

[0043] In the display area AA2 of the second liquid crystal display panel 20, pixel electrodes PX are laminated on the liquid crystal layer 3 side of the first substrate 21, and an insulating layer 23 is laminated on the liquid crystal layer 3 side of the pixel electrodes PX.

[0044] In addition, in the display area AA2 of the second liquid crystal display panel 20, a common electrode COML is laminated on the liquid crystal layer 3 side of the second substrate 22, an insulating layer 24 is laminated on the liquid crystal layer 3 side of the common electrode COML, and a polarizing plate 26 is attached to the outer side of the second substrate 22. In addition, in the display area AA2 of the second liquid crystal display panel 20, a color filter 25 is laminated on the liquid crystal layer 3 side of the insulating layer 24.

[0045] The pixel electrode PX is a plate-shaped or film-shaped electrode provided for each pixel Pix, and the common electrode COML is a plate-shaped or film-shaped electrode shared by multiple pixels Pix.

[0046] In the liquid crystal layer 3, the potential of the pixel electrode PX is individually controlled for each pixel Pix, so that the orientation state of the liquid crystal molecules 32 in the bulk 31 changes according to the potential difference between the pixel electrode PX and the common electrode COML, thereby controlling the scattering state for each pixel Pix.

[0047] 6A and 6B show an example in which the pixel electrode PX provided on the first substrate 21 and the common electrode COML provided on the second substrate 22 are arranged opposite each other with the liquid crystal layer 3 sandwiched therebetween, but the first liquid crystal display panel 10 and the second liquid crystal display panel 20 may each be configured such that the pixel electrode PX and the common electrode COML are provided on one substrate, and the orientation changes due to the electric field generated by the pixel electrode PX and the common electrode COML, thereby controlling the scattering state of the liquid crystal layer 3.

[0048] Next, a mechanism for controlling the potentials of the pixel electrodes PX and the common electrode COML in the display area AA1 of the first liquid crystal display panel 10 and the display area AA2 of the second liquid crystal display panel 20 will be described.

[0049] The pixel transistor Tr is a switching element using a semiconductor, such as a thin film transistor (TFT). One of the source or drain of the pixel transistor Tr is connected to the pixel electrode PX. The other of the source or drain of the pixel transistor Tr is connected to a signal line DTL. The gate of the pixel transistor Tr is connected to a scanning line SCL. The scanning line SCL applies a driving potential to drive the pixel transistor Tr under the control of the scanning circuits 17 and 27. The driving potential is controlled by the scanning circuits 17 and 27.

[0050] In the example shown in FIG. 5, multiple signal lines SCL are arranged along one of the arrangement directions of the pixels Pix (row direction). The signal line DTL extends along the other of the arrangement directions of the pixels Pix (column direction). The signal line DTL is shared by the pixel transistors Tr of multiple pixels Pix arranged in the column direction. Multiple scanning lines SCL are arranged along the column direction. The scanning line SCL extends along the row direction. The scanning line SCL is shared by the pixel transistors Tr of multiple pixels Pix arranged in the row direction.

[0051] A common potential VCOM is applied to the common electrode COML. The scanning circuits 17 and 27 supply a driving potential to the scanning line SCL to drive the pixel transistor Tr, and when the pixel transistor Tr is controlled to be on, the signal output circuits 16 and 26 supply a pixel signal to the signal line DTL. As a result, a voltage corresponding to the pixel signal is applied between the pixel electrode PX and the common electrode COML, and the pixel capacitance Cs is charged.

[0052] After the pixel transistor Tr is turned off, the charge potential of the pixel capacitance Cs between the pixel electrode PX and the common electrode COML is maintained. The degree of scattering of the liquid crystal layer 3 (liquid crystal molecules 32) is controlled according to the charge potential of the pixel capacitance Cs between the pixel electrode PX and the common electrode COML for each pixel Pix.

[0053] Next, the non-display areas NA1 and NA2 according to the present disclosure will be described. Figure 7A is a schematic cross-sectional view of the non-display area of ​​the first liquid crystal display panel. Figure 7B is a schematic cross-sectional view of the non-display area of ​​the second liquid crystal display panel.

[0054] The non-display area NA1 of the first liquid crystal display panel 10 is an area overlapping the second liquid crystal display panel 20, similar to the display area AA1 of the first liquid crystal display panel 10, and is an area provided with a liquid crystal layer 3 and a polarizer 16. The non-display area NA2 of the second liquid crystal display panel 20 is an area overlapping the first liquid crystal display panel 10, similar to the display area AA2 of the second liquid crystal display panel 20, and is an area provided with a liquid crystal layer 3 and a polarizer 26. On the other hand, no pixels Pix are provided in the non-display area NA1 of the first liquid crystal display panel 10 or the non-display area NA2 of the second liquid crystal display panel 20.

[0055] 7A, the non-display area NA1 of the first liquid crystal display panel 10 does not have any pixel electrodes PX stacked on the liquid crystal layer 3 side of the first substrate 11 in the display area AA1 of the first liquid crystal display panel 10. Furthermore, the non-display area NA1 of the first liquid crystal display panel 10 does not have any common electrodes COML stacked on the liquid crystal layer 3 side of the second substrate 12 in the display area AA1 of the first liquid crystal display panel 10, or any color filters 15 stacked on the liquid crystal layer 3 side of the insulating layer 14.

[0056] 7B, the non-display area NA2 of the second liquid crystal display panel 20 does not have any pixel electrodes PX laminated on the liquid crystal layer 3 side of the first substrate 21 in the display area AA2 of the second liquid crystal display panel 20. The non-display area NA2 of the second liquid crystal display panel 20 also does not have any common electrodes COML laminated on the liquid crystal layer 3 side of the second substrate 22 in the display area AA2 of the second liquid crystal display panel 20, or any color filters 25 laminated on the liquid crystal layer 3 side of the insulating layer 24.

[0057] 5, pixel transistors Tr are not provided in the non-display area NA1 of the first liquid crystal display panel 10 and the non-display area NA2 of the second liquid crystal display panel 20. Furthermore, scanning lines SCL for applying a drive potential to the pixel transistors Tr and signal lines DTL for supplying pixel signals to the pixel transistors Tr are not provided in the non-display area NA1 of the first liquid crystal display panel 10 and the non-display area NA2 of the second liquid crystal display panel 20.

[0058] In the present disclosure, as described above, the first liquid crystal display panel 10 and the second liquid crystal display panel 20 are arranged to overlap in the optical axis direction (Z direction) of the magnifying optical system. Specifically, the second liquid crystal display panel 20 is arranged with a gap S provided between it and the first liquid crystal display panel 10. Direct light from the backlight 30 is incident on the first liquid crystal display panel 10. Transmitted light from the first liquid crystal display panel 10 is incident on the second liquid crystal display panel 20.

[0059] As described above, in the display device 1 according to the embodiment, the display area AA1 of the first liquid crystal display panel 10 is provided with an insulating layer 13 and a color filter 15. The color filter 15 is provided between the polarizer 16 and the second liquid crystal display panel 20.

[0060] As described above, in the display device 1 according to the embodiment, the insulating layer 24 and the color filter 25 are provided in the display area AA2 of the second liquid crystal display panel 20. The color filter 25 is provided between the polarizing plate 26 and the first liquid crystal display panel 10.

[0061] When incident light passes through the first liquid crystal display panel 10, the amount of light is adjusted according to the gradation value of the pixel Pix provided at a position corresponding to the display image of the first liquid crystal display panel 10, and the light is emitted as transmitted light. When incident light passes through the second liquid crystal display panel 20, the amount of light is adjusted according to the gradation value of the pixel Pix provided at a position corresponding to the display image of the second liquid crystal display panel 20, and the light is emitted as transmitted light.

[0062] The polarizing plate 16 is an optical member that transmits light polarized in a first direction and blocks light polarized in a direction different from the first direction. Specifically, the polarizing plate 16 is a linear polarizing plate having a transmission axis in the Y direction, for example.

[0063] The polarizing plate 26 is an optical member that transmits light polarized in a second direction different from the first direction and blocks light polarized in a direction different from the second direction. Specifically, the polarizing plate 26 is a linear polarizing plate having a transmission axis in the X direction, for example.

[0064] In the present disclosure, no polarizing plate is provided between the first liquid crystal display panel 10 and the second liquid crystal display panel 20, and the polarizing plate 16 and the polarizing plate 26 are arranged with their transmission axes perpendicular to each other with respect to the incident light (crossed Nicols). The liquid crystal layers 3 of the first liquid crystal display panel 10 and the second liquid crystal display panel 20 are initially aligned to maximize the transmittance. This maximizes the transmittance of the non-display area NA1 of the first liquid crystal display panel 10 and the non-display area NA2 of the second liquid crystal display panel 20.

[0065] The color filter 15 and the color filter 25 each include a red color resist CR that transmits red light, a green color resist CG that transmits green light, and a blue color resist CB that transmits blue light. The color resists of each color are provided corresponding to the plurality of pixels Pix of the first liquid crystal display panel 10 and the second liquid crystal display panel 20. A light-shielding film BM is provided between the color resists of each color.

[0066] In the above-described configuration, the color image (first image) displayed in the display area AA1 of the first liquid crystal display panel 10 passes through the second liquid crystal display panel 20 and is visually recognized by the observer OB as a virtual image VIF.

[0067] In the above-described configuration, the color image (second image) displayed in the display area AA2 of the second liquid crystal display panel 20 is visually recognized by the observer OB as a virtual image VIR due to light transmitted through the first liquid crystal display panel .

[0068] Here, when the display region AA1 of the first liquid crystal display panel 10 and the display region AA2 of the second liquid crystal display panel 20 overlap in the Z direction, the chromaticity of the virtual image VIR of the first image viewed by the observer OB is changed by the color filter 25 provided in the display region AA2 of the second liquid crystal display panel 20. Furthermore, the chromaticity of the transmitted light that passes through the display region AA1 of the first liquid crystal display panel 10 and enters the display region AA2 of the second liquid crystal display panel 20 is changed by the color filter 15 provided in the display region AA1 of the first liquid crystal display panel 10. Therefore, the chromaticity of the virtual image VIF of the second image viewed by the observer OB is changed by the color filter 15 provided in the display region AA1 of the first liquid crystal display panel 10. Furthermore, due to the reduction in transmittance and aperture ratio caused by the dual provision of the color filters 15 and 25, the luminance of the virtual image VIR of the first image and the virtual image VIF of the second image viewed by the observer OB is reduced.

[0069] For this reason, in the present disclosure, the display region AA1 of the first liquid crystal display panel 10 and the display region AA2 of the second liquid crystal display panel 20 do not overlap at least in one direction in which the first liquid crystal display panel 10 and the second liquid crystal display panel 20 overlap, specifically, when viewed from the optical axis direction (Z direction) of the magnifying optical system. In other words, the display region AA1 of the first liquid crystal display panel 10 and the non-display region NA2 of the second liquid crystal display panel 20 overlap, and the display region AA2 of the second liquid crystal display panel 20 overlaps with the non-display region NA1 of the first liquid crystal display panel 10, at least in one direction in which the first liquid crystal display panel 10 and the second liquid crystal display panel 20 overlap, specifically, when viewed from the optical axis direction (Z direction) of the magnifying optical system. This makes it possible to suppress degradation in the display quality of the virtual image VIR of the first image and the virtual image VIF of the second image that are reflected by the light-transmitting member FG and viewed by the observer OB. Below, specific configuration examples of the first liquid crystal display panel 10 and the second liquid crystal display panel 20 in the display device 1 according to the present disclosure will be described.

[0070] Fig. 8 is a diagram showing a first example of a display mode of a first image. Fig. 9 is a diagram showing a first example of a display mode of a second image. Fig. 10 is a cross-sectional view of the display device according to the embodiment, taken along the arrow AA shown in Figs. 8 and 9. Fig. 11 is a diagram showing a first example of a virtual image visually recognized by an observer.

[0071] 8 indicates a non-display area NA1 of the first liquid crystal display panel 10. The first image is displayed in a display area AA1 of the first liquid crystal display panel 10.

[0072] 9 indicates a non-display area NA2 of the second liquid crystal display panel 20. The second image is displayed in a display area AA2 of the second liquid crystal display panel 20.

[0073] 8, 9, and 11, as shown in Fig. 10, an example is shown in which, when viewed at least from the direction in which the first liquid crystal display panel 10 and the second liquid crystal display panel 20 overlap, the display area AA1 of the first liquid crystal display panel 10 overlaps with the non-display area NA2 of the second liquid crystal display panel 20, and the display area AA2 of the second liquid crystal display panel 20 overlaps with the non-display area NA1 of the first liquid crystal display panel 10. More specifically, the display area AA1 of the first liquid crystal display panel 10 overlaps with the non-display area NA2 of the second liquid crystal display panel 20 in the optical axis direction (Z direction) of the magnifying optical system, and the display area AA2 of the second liquid crystal display panel 20 overlaps with the non-display area NA1 of the first liquid crystal display panel 10 in the optical axis direction (Z direction) of the magnifying optical system. As a result, as shown in Figure 11, the virtual image VIR of the first image displayed in the display area AA1 of the first liquid crystal display panel 10 and the virtual image VIF of the second image displayed in the display area AA2 of the second liquid crystal display panel 20 are viewed so as not to overlap in the line of sight of the observer OB.

[0074] In the present disclosure, as described above, no polarizing plate is provided between the first liquid crystal display panel 10 and the second liquid crystal display panel 20, and the polarizing plate 16 and the polarizing plate 26 are arranged in a state in which their transmission axes are perpendicular to each other with respect to the incident light (crossed Nicols). The liquid crystal layer 3 of the first liquid crystal display panel 10 is initially aligned so that the transmittance of the non-display area NA1 of the first liquid crystal display panel 10 is maximized. This makes it possible to suppress degradation in the display quality of the second image viewed by the observer OB.

[0075] Specifically, it is possible to suppress chromaticity changes and luminance reductions in the virtual image VIF of the second image viewed by the observer OB by not providing the color filter 15 at least in the non-display area NA1 of the first liquid crystal display panel 10. Furthermore, it is possible to further suppress luminance reductions in the virtual image VIF of the second image viewed by the observer OB by not providing the pixel electrodes PX, the common electrode COML, the pixel transistors Tr, the scanning lines SCL, the signal lines DTL, etc. in the non-display area NA1 of the first liquid crystal display panel 10.

[0076] Furthermore, in the present disclosure, as described above, the liquid crystal layer 3 of the second liquid crystal display panel 20 is initially aligned so as to maximize the transmittance of the non-display area NA2 of the second liquid crystal display panel 20. This makes it possible to suppress degradation in the display quality of the first image viewed by the observer OB.

[0077] Specifically, it is possible to suppress chromaticity changes and luminance reduction in the virtual image VIR of the first image viewed by the observer OB by not providing the color filter 25 at least in the non-display area NA2 of the second liquid crystal display panel 20. Furthermore, it is possible to further suppress luminance reduction in the virtual image VIR of the first image viewed by the observer OB by not providing the pixel electrodes PX, the common electrode COML, the pixel transistors Tr, the scanning lines SCL, the signal lines DTL, etc. in the non-display area NA2 of the second liquid crystal display panel 20.

[0078] Fig. 12 is a diagram showing a second example of a display mode of the first image, Fig. 13 is a diagram showing a second example of a display mode of the second image, and Fig. 14 is a diagram showing a second example of a virtual image visually recognized by an observer.

[0079] 12, 13, and 14, the display area and non-display area of ​​the first liquid crystal display panel 10 and the second liquid crystal display panel 20 are arranged symmetrically to each other, which allows the display device 1 to be configured using the same two liquid crystal display panels.

[0080] 12, 13, and 14, the display area and the non-display area are arranged symmetrically in the vertical direction, but the present invention is not limited to this. Specifically, for example, the display area and the non-display area may be arranged symmetrically in the horizontal direction, or the display area and the non-display area may be arranged symmetrically in the diagonal direction.

[0081] Fig. 15 is a diagram showing a third example of a display mode of the first image. Fig. 16 is a diagram showing a third example of a display mode of the second image. Fig. 17 is a cross-sectional view of the display device according to the embodiment, taken along the arrow BB shown in Figs. 15 and 16. Fig. 18 is a diagram showing a third example of a virtual image visually recognized by an observer.

[0082] In the third example shown in FIGS. 15, 16, and 18, the first liquid crystal display panel 10 is not provided with a non-display area.

[0083] 15, 16, and 18, the display area AA1 of the first liquid crystal display panel 10 and the non-display area NA2 of the second liquid crystal display panel 20 are configured to overlap at least when viewed from the direction in which the first liquid crystal display panel 10 and the second liquid crystal display panel 20 overlap, as shown in Fig. 17. More specifically, the display area AA1 of the first liquid crystal display panel 10 and the non-display area NA2 of the second liquid crystal display panel 20 overlap in the optical axis direction (Z direction) of the magnifying optical system. This allows the virtual image VIR of the first image displayed in the display area AA1 of the first liquid crystal display panel 10 and the virtual image VIF of the second image displayed in the display area AA2 of the second liquid crystal display panel 20 to be viewed so as not to overlap in the line of sight of the observer OB.

[0084] In the present disclosure, as described above, the initial alignment is set to maximize the transmittance of the non-display area NA2 of the second liquid crystal display panel 20. This makes it possible to suppress degradation in the display quality of the first image and the second image viewed by the observer OB.

[0085] Specifically, it is possible to suppress chromaticity changes and luminance reduction in the virtual image VIR of the first image viewed by the observer OB by not providing the color filter 25 at least in the non-display area NA2 of the second liquid crystal display panel 20. Furthermore, it is possible to further suppress luminance reduction in the virtual image VIR of the first image viewed by the observer OB by not providing the pixel electrodes PX, the common electrode COML, the pixel transistors Tr, the scanning lines SCL, the signal lines DTL, etc. in the non-display area NA2 of the second liquid crystal display panel 20.

[0086] (First Modification) 19 is a schematic diagram of a HUD showing an application example of a display device according to a first modified example of an embodiment. Note that a configuration different from that of the first embodiment will be described here, and overlapping descriptions may be omitted.

[0087] In the configuration according to the first modified example of the embodiment, the first liquid crystal display panel 10 is disposed in a tilted state with respect to the second liquid crystal display panel 20. The second liquid crystal display panel 20 is disposed approximately parallel to an XY plane perpendicular to the optical axis of the magnifying optical system 2. The tilt angle of the first liquid crystal display panel 10 with respect to the second liquid crystal display panel 20 (the XY plane perpendicular to the optical axis of the magnifying optical system 2) is set to, for example, about 40 degrees. As a result, a virtual image VIR of the first image displayed on the first liquid crystal display panel 10 is viewed by the observer OB in a tilted state with respect to a virtual image VIF of the second image displayed on the second liquid crystal display panel 20.

[0088] More specifically, in the configuration according to the first modified example of the embodiment shown in FIG. 19, the virtual image VIR of the first image is viewed from the viewpoint of the observer OB, from bottom to top, tilting from the front to the back.

[0089] To achieve this display mode, the first liquid crystal display panel 10a is arranged at an angle relative to the XY plane, which is approximately parallel to the second liquid crystal display panel 20, so that the gap S between it and the second liquid crystal display panel 20 is large at the upper end in the Y direction and small at the lower end in the Y direction (see Figure 11D).

[0090] In this way, in the configuration related to the first variant of the embodiment, in an area where the virtual image VIR of the first image and the virtual image VIF of the second image are viewed by the observer OB while overlapping in the direction of the observer OB's line of sight, the virtual image VIR of the first image can be viewed at an angle relative to the virtual image VIF of the second image.

[0091] Furthermore, by tilting the first liquid crystal display panel 10 relative to the XY plane that is approximately parallel to the second liquid crystal display panel 20 so that the gap S between the first liquid crystal display panel 10 and the second liquid crystal display panel 20 is large at the upper end in the Y direction and small at the lower end in the Y direction, a virtual image VIR of the first image that is tilted from bottom to top and from the front to the back can be viewed from the viewpoint of the observer OB.

[0092] (Second Modification) 20 is a schematic diagram of a HUD showing an application example of a display device according to a second modified example of the embodiment. Note that, here, a configuration different from that of the first embodiment will be described, and overlapping descriptions may be omitted.

[0093] In the configuration according to the second modification of the embodiment, the second liquid crystal display panel 20 is disposed in a state inclined with respect to the XY plane perpendicular to the optical axis of the magnifying optical system 2.

[0094] In the second modified example shown in FIG. 20, the tilt direction of the second liquid crystal display panel 20 with respect to the XY plane is, for example, rotated 180 degrees in the XY plane with respect to the tilt direction of the first liquid crystal display panel 10 with respect to the XY plane.

[0095] The tilt angle of the second liquid crystal display panel 20 with respect to the XY plane may be smaller than the tilt angle of the first liquid crystal display panel 10 with respect to the XY plane. Specifically, for example, if the tilt angle of the first liquid crystal display panel 10 with respect to the XY plane is approximately 40 degrees, the tilt angle of the second liquid crystal display panel 20 with respect to the XY plane is approximately 20 degrees. As a result, sunlight incident from the optical axis direction of the magnifying optical system 2 is reflected by the surface of the second liquid crystal display panel 20 (the surface of the polarizing plate 26) in a direction deviated from the optical axis of the magnifying optical system 2. This makes it possible to prevent sunlight reflected by the surface of the second liquid crystal display panel 20 (the surface of the polarizing plate 26) from entering the eyes of the observer OB.

[0096] The tilt direction of the second liquid crystal display panel 20 is not limited to the embodiment shown in Fig. 20. Specifically, for example, the tilt direction of the second liquid crystal display panel 20 with respect to the XY plane may be the same as the tilt direction of the first liquid crystal display panel 10 with respect to the XY plane. The tilt direction of the second liquid crystal display panel 20 does not limit the present disclosure.

[0097] Although preferred embodiments of the present disclosure have been described above, the present disclosure is not limited to such embodiments. The contents disclosed in the embodiments are merely examples, and various modifications are possible within the scope of the present disclosure. For example, appropriate modifications made within the scope of the present disclosure naturally fall within the technical scope of the present invention. [Explanation of symbols]

[0098] 1 Display device 2. Magnifying optical system 3 Liquid crystal layer 10 First liquid crystal display panel 13 Insulating layer 15 Color Filters 16 Polarizing Plate 20 Second LCD panel 24 insulating layer 25 Color Filters 26 Polarizing Plate 30 Backlight 100 HUD (Head-Up Display) EB, EB1, EB2 Eye Box FG Translucent material L light O Lens OB Observer VI Virtual Image VIF Virtual image (second image) VIR Virtual image (first image)

Claims

1. Backlight and a first liquid crystal display panel onto which direct light from the backlight is incident; a second liquid crystal display panel that overlaps the first liquid crystal display panel with a gap therebetween and into which transmitted light from the first liquid crystal display panel is incident; Equipped with the first liquid crystal display panel includes a display area for displaying an image; the second liquid crystal display panel includes a display area for displaying an image and a non-display area for not displaying an image; a display area of ​​the first liquid crystal display panel and a non-display area of ​​the second liquid crystal display panel overlap each other when viewed from at least one direction in which the first liquid crystal display panel and the second liquid crystal display panel overlap each other; a display area of ​​the first liquid crystal display panel is provided with at least a liquid crystal layer, a polarizing plate, and a color filter; the non-display area of ​​the second liquid crystal display panel is provided with at least a liquid crystal layer and a polarizing plate, and is not provided with a color filter; Display device.

2. a pixel transistor for applying a voltage to a liquid crystal layer is provided in a display area of ​​the first liquid crystal display panel; No pixel transistors are provided in the non-display area of ​​the second liquid crystal display panel. The display device according to claim 1 .

3. a pixel electrode connected to a pixel transistor is provided in a display area of ​​the first liquid crystal display panel; No pixel electrodes are provided in the non-display area of ​​the second liquid crystal display panel. The display device according to claim 2 .

4. a common electrode is provided in a display area of ​​the first liquid crystal display panel, the common electrode being opposed to the pixel electrodes with a liquid crystal layer interposed therebetween; No common electrode is provided in the non-display area of ​​the second liquid crystal display panel. The display device according to claim 3 .

5. a display area of ​​the first liquid crystal display panel is provided with scanning lines that apply a driving potential to pixel transistors, and signal lines that supply pixel signals to the pixel transistors when the driving potential is applied to the pixel transistors and the pixel transistors are turned on; No scanning lines or signal lines are provided in the non-display area of ​​the second liquid crystal display panel. The display device according to claim 4 .

6. the first liquid crystal display panel includes a non-display area in which an image cannot be displayed; a non-display area of ​​the first liquid crystal display panel and a display area of ​​the second liquid crystal display panel overlap each other when viewed from at least one direction in which the first liquid crystal display panel and the second liquid crystal display panel overlap each other; a display area of ​​the second liquid crystal display panel is provided with at least a liquid crystal layer, a polarizing plate, and a color filter; The non-display area of ​​the first liquid crystal display panel is provided with at least a liquid crystal layer and a polarizing plate, but is not provided with a color filter. The display device according to claim 1 .

7. a pixel transistor for applying a voltage to a liquid crystal layer is provided in a display area of ​​the second liquid crystal display panel; No pixel transistors are provided in the non-display area of ​​the first liquid crystal display panel. The display device according to claim 6.

8. a pixel electrode connected to a pixel transistor is provided in a display area of ​​the second liquid crystal display panel; No pixel electrodes are provided in the non-display area of ​​the first liquid crystal display panel. The display device according to claim 7 .

9. a common electrode is provided in a display area of ​​the second liquid crystal display panel, the common electrode being opposed to the pixel electrodes with a liquid crystal layer interposed therebetween; No common electrode is provided in the non-display area of ​​the first liquid crystal display panel. The display device according to claim 8 .

10. a display area of ​​the second liquid crystal display panel is provided with scanning lines that apply a driving potential to pixel transistors, and signal lines that supply pixel signals to the pixel transistors when the driving potential is applied to the pixel transistors and the pixel transistors are turned on; No scanning lines or signal lines are provided in the non-display area of ​​the first liquid crystal display panel. The display device according to claim 9 .

11. the polarizing plate provided on the first liquid crystal display panel and the polarizing plate provided on the second liquid crystal display panel are arranged such that their transmission axes are perpendicular to each other with respect to incident light; a liquid crystal layer provided in the first liquid crystal display panel and a liquid crystal layer provided in the second liquid crystal display panel are initially aligned so as to maximize transmittance; The display device according to any one of claims 1 to 10.

12. No other polarizing plate is provided between the first liquid crystal display panel and the second liquid crystal display panel. The display device according to claim 11.

13. A head-up display in which an image reflected by a translucent member that transmits and reflects incident light is superimposed on a real image that has passed through the translucent member, allowing an observer to visually recognize the image as a virtual image, A display device according to any one of claims 1 to 10; an enlarging optical system that enlarges an image displayed on the display device and projects the enlarged image onto the light-transmitting member; Equipped with the polarizing plate provided on the first liquid crystal display panel and the polarizing plate provided on the second liquid crystal display panel are arranged such that their transmission axes are perpendicular to each other with respect to incident light; a liquid crystal layer provided in the first liquid crystal display panel and a liquid crystal layer provided in the second liquid crystal display panel are initially aligned so as to maximize transmittance; Head-up display.

14. No other polarizing plate is provided between the first liquid crystal display panel and the second liquid crystal display panel.

14. The head-up display of claim 13.

15. a virtual distance from a viewpoint of the observer to a virtual image of the first image displayed on the first liquid crystal display panel is greater than a virtual distance from a viewpoint of the observer to a virtual image of the second image displayed on the second liquid crystal display panel; 15. The head-up display of claim 14.

16. the first liquid crystal display panel and the second liquid crystal display panel overlap in the viewer's line of sight; 16. The head-up display of claim 15.

17. the first liquid crystal display panel is disposed at an angle with respect to a plane perpendicular to the viewer's line of sight; 17. The head-up display of claim 16.

18. the second liquid crystal display panel is disposed at an angle with respect to a plane perpendicular to the viewer's line of sight; 17. The head-up display of claim 16.

19. The first liquid crystal display panel is disposed at an angle with respect to the second liquid crystal display panel.

17. The head-up display of claim 16.

Images