Display device for vehicle

Abstract

The invention relates to a display device for a vehicle. A display device for a vehicle according to an embodiment of the present disclosure may include: an image generation device for outputting a first polarized projection image; a concave mirror including a phase retardation layer for polarization conversion between the first polarized light and the second polarized light; and a transparent cover including a polarizing layer for transmitting the first polarized light and reflecting the second polarized light. The concave mirror may convert a first polarized projection image output from the image generation device into a second polarized projection image and may primarily reflect the second polarized projection image to the transparent cover. The transparent cover may reflect the second polarized projection image to the concave mirror. The concave mirror may convert the second polarized projection image into the first polarized projection image and may secondarily reflect the first polarized projection image to the transparent cover. The transparent cover may transmit the first polarized projection image. Therefore, the size can be reduced while an image is projected on a large screen.

Description

TECHNICAL FIELD

[0001] The disclosure relates to a display device for a vehicle, and more particularly, to a display device for a vehicle that can reduce a size while implementing a large-screen projection image. BACKGROUND

[0002] A vehicle is an apparatus that moves in a direction desired by a user who rides the vehicle. A representative example is an automobile.

[0003] In addition, in order to facilitate the use of the vehicle by the user, a display device for a vehicle is installed inside the vehicle.

[0004] For example, a display is placed on a cluster or the like to display various types of information. In addition, in order to display vehicle driving information or the like separately from the cluster, various displays such as an audio video navigation (AVN) display and a head-up display configured to output a projection image on a windshield are installed in the vehicle.

[0005] In addition, information displayed through the head-up display is increasing. For example, in order to implement an augmented reality-based head-up display, information such as a road, a vehicle, and a surrounding object needs to be displayed, so that a screen of the head-up display needs to be increased, and ultimately a size of the head-up display needs to be increased.

[0006] An increase in the size of the head-up display causes installation constraints inside the vehicle. SUMMARY

[0007] TECHNICAL PROBLEM

[0008] The disclosure is proposed to solve the above-described problems, and aims to provide a display device for a vehicle that can be small in size to facilitate installation inside the vehicle while securing an optical path sufficient to implement a large-screen projection image.

[0009] TECHNICAL SOLUTION

[0010] To achieve the above object, according to one aspect of the present disclosure, there is provided a display device for a vehicle, the display device for a vehicle including: an image generating device outputting a first polarized projection image; a concave mirror including a phase retardation layer for polarization conversion between a first polarized light and a second polarized light; and a transparent cover including a polarizing layer for transmitting the first polarized light therethrough and reflecting the second polarized light, wherein the concave mirror converts the first polarized projection image output from the image generating device into the second polarized projection image and reflects the second polarized projection image to the transparent cover once, wherein the transparent cover reflects the second polarized projection image to the concave mirror, wherein the concave mirror converts the second polarized projection image into the first polarized projection image and reflects the first polarized projection image to the transparent cover twice, and wherein the transparent cover transmits the first polarized projection image therethrough.

[0011] The display device can further include a motor adjusting a position of the first polarized projection image transmitted through the transparent cover.

[0012] The once mirror reflection area of the concave mirror can be positioned closer to a front of the vehicle than a twice mirror reflection area of the concave mirror.

[0013] The once mirror reflection area can be narrower than the twice mirror reflection area.

[0014] The cover reflection area of the transparent cover can be positioned closer to the front of the vehicle than a cover transmission area of the transparent cover.

[0015] The cover reflection area can be narrower than the cover transmission area.

[0016] The first polarized light can be P-polarized light and the second polarized light can be S-polarized light.

[0017] The image generating device can include one of a liquid crystal display (LCD), an organic light emitting diode (OLED), a digital mirror device, and a micro light emitting diode (LED).

[0018] The phase retardation layer can include a quarter wave plate.

[0019] A first optical path of the once-reflected second polarized projection image from the concave mirror to the transparent cover can be shorter than a second optical path of the second polarized projection image reflected by the transparent cover from the transparent cover to the concave mirror.

[0020] The second optical path can be shorter than a third optical path of the twice-reflected first polarized projection image from the concave mirror to the transparent cover.

[0021] The second polarized projection image transmitted through the transparent cover can be irradiated to a windshield of the vehicle.

[0022] The display device for a vehicle can include a head-up display (HUD).

[0023] Advantages

[0024] Effects of the display device for a vehicle according to the disclosure will be described as follows.

[0025] According to at least one of the various aspects of the disclosure, the display device for a vehicle can be small in size to facilitate installation within a vehicle while ensuring a light path sufficient to implement a large-screen projection image. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 FIG. 1 is a diagram illustrating an example of an exterior and an interior of a vehicle.

[0027] Figure 2 and Figure 3 FIG. 2 is a diagram illustrating various examples of an internal configuration of a display device for a vehicle related to the disclosure.

[0028] Figure 4 FIG. 3 is a diagram illustrating an example of an internal configuration of a display device for a vehicle according to one aspect of the disclosure.

[0029] Figure 5 is a magnified sectional view of a concave mirror of a display device for a vehicle in Figure 4

[0030] Figure 6 illustrates a light path and a polarization conversion of a projection image in a display device for a vehicle in Figure 4

[0031] Figure 7 is a diagram for illustrating a reflection region and a transmission region in a display device for a vehicle in Figure 4

[0032] Figure 8 is a diagram for illustrating a light path of a projection image of a display device for a vehicle in Figure 4

[0033] Figure 9 is a diagram for comparing a size of a display device for a vehicle in Figure 3 Figure 4 DETAILED DESCRIPTION

[0034] ​​​​​​A description will now be given in detail with reference to the accompanying drawings based on exemplary embodiments disclosed herein. For the sake of brevity of description with reference to the drawings, the same or equivalent components can be provided with the same reference numbers, and a description thereof will not be repeated. In general, suffixes such as "module" and "unit" can be used to refer to elements or components. Such suffixes are used herein merely to facilitate description of the specification, and the suffix itself is not intended to give any special meaning or function. In the present disclosure, for the sake of brevity, matters known to those of ordinary skill in the relevant art are generally not described. The accompanying drawings serve to facilitate easy understanding of various technical features, and it should be understood that the embodiments presented herein are not limited by the accompanying drawings. Accordingly, the present disclosure should be interpreted as extending to any changes, equivalents, and substitutions other than those specifically set forth in the accompanying drawings.

[0035] It should be understood that, although the terms first, second, etc. can be used herein to describe various elements, these elements should not be limited by these terms. These terms are generally only used to distinguish one element from another.

[0036] It should be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements can also be present. In contrast, when an element is referred to as being "directly connected" to another element, there are no intervening elements present.

[0037] The singular representation can include the plural representation, unless it represents a meaning clearly different from the context.

[0038] The terms such as "include" or "have" are used herein, and it should be understood that they are intended to indicate the presence of several components, functions or steps disclosed in the specification and it should also be understood that a greater or fewer number of components, functions or steps can be similarly used.

[0039] Hereinafter, a description will be given with reference to Figure 1 Examples of the exterior and interior of the vehicle are described. Figure 1 is a diagram showing examples of the exterior and interior of the vehicle.

[0040] As Figure 1 shown, the vehicle 200 is operated by a plurality of wheels 103FR, 103FL, 103RL,..., which are rotated by a power source and a steering wheel 150 to control the moving direction of the vehicle 200.

[0041] In addition, the vehicle 200 can further include a camera 195 for obtaining an image of the front of the vehicle.

[0042] In addition, the vehicle 200 can include a plurality of displays 180a, 180b, 180h that display images, information, etc. provided therein.

[0043] For example, among the plurality of displays 180a, 180b, 180h, the first display 180a can be an instrument panel display, the second display 180b can be an audio video navigation (AVN) display, and the third display 180h can be a HUD display that is a head-up display (HUD) that projects an image onto a specific separate area Ara on the windshield WS. The specific separate area Ara can correspond to an eye box of a user (or driver).

[0044] Further, the display device for a vehicle according to the present disclosure is a device for the HUD display 180h.

[0045] Further, as illustrated, a black mask area or a frit area Fz can be formed in a lower area of the windshield WS.

[0046] In one example, the vehicle 200 described herein can be a concept that includes all vehicles equipped with an engine as a power source, a hybrid vehicle equipped with an engine and an electric motor as power sources, an electric vehicle equipped with an electric motor as a power source, and the like.

[0047] Hereinafter, referring to Figure 2 and Figure 3 , internal components of the display device for a vehicle according to the present disclosure will be described. Figure 2 and Figure 3 are diagrams illustrating various examples of internal components of the display device for a vehicle according to the present disclosure.

[0048] Figure 2 Examples of the display device for a vehicle according to the present disclosure are illustrated.

[0049] Referring to Figure 2 , the display device 100x for a vehicle according to the present disclosure includes a liquid crystal display panel (or a picture generation unit (PGU)) 300x configured to output a projection image, a folding mirror 315x configured to reflect the projection image from the liquid crystal display panel 300x, and a concave mirror 325x configured to reflect the projection image from the folding mirror 315x to the windshield WS.

[0050] The projection image reflected from the specific area Arx of the windshield WS is output to the line-of-sight area Ara of the driver.

[0051] The concave mirror 325x in the display device for a vehicle 100x is disposed between the liquid crystal display panel 300x and the driver's line-of-sight area Ara. That is, the concave mirror 325x can be positioned between two virtual parallel lines passing through the liquid crystal display panel 300x and the driver's line-of-sight area Ara, respectively, and has a gap corresponding to a separation distance between the liquid crystal display panel 300x and the driver's line-of-sight area Ara.

[0052] Further, the concave mirror 325x in the display device for a vehicle 100x determines the arrangement of the projection image and the position of the light source.

[0053] For example, by increasing the magnification of the concave mirror 325x in the display device for a vehicle 100x and decreasing the focal length, the size SZx of the display device for a vehicle 100x can be reduced.

[0054] However, when the size is thus reduced, it is difficult to implement a large-screen projection image, and thus it is difficult to implement an AR HUD.

[0055] Figure 3 Another example of a display device for a vehicle according to the present disclosure is illustrated.

[0056] Reference Figure 3 The display device for a vehicle 100y according to the present disclosure includes a liquid crystal display panel 300y outputting a projection image, a folding mirror 315y reflecting the projection image from the liquid crystal display panel 300y, a concave mirror 325y reflecting the projection image from the folding mirror 315y, and a transparent cover 335y outputting the projection image from the concave mirror 325y to the windshield WS.

[0057] The projection image reflected from the predetermined area Ary of the windshield WS is output to the driver's line-of-sight area Ara.

[0058] Unlike Figure 2 The concave mirror 325y in the display device for a vehicle 100y is disposed in front of the liquid crystal display panel 300y and the driver's line-of-sight area Ara.

[0059] That is, the liquid crystal display panel 300y in the display device for a vehicle 100y is disposed between the concave mirror 325y and the driver's line-of-sight area Ara. That is, the liquid crystal display panel 300y can be positioned within a space defined by two virtual parallel lines passing through the concave mirror 325y and the driver's line-of-sight area Ara, respectively, the space corresponding to a separation distance between the concave mirror 325y and the driver's line-of-sight area Ara.

[0060] In one example, the concave mirror 325y in the display device for a vehicle 100y determines the arrangement of the projection image and the position of the light source.

[0061] For example, when the magnification of the concave mirror 325y in the display device for a vehicle 100y is increased and its focal length is reduced, the size SZy of the display device for a vehicle 100y can be reduced.

[0062] However, when the size is thus reduced, it is difficult to implement a large-screen projected image, and thus it is difficult to implement an AR HUD.

[0063] Accordingly, the present disclosure proposes a method for reducing the size of a display device for a vehicle while implementing a large-screen projected image.

[0064] In particular, unlike the display device for a vehicle 100 shown in FIG. 1, a display device for a vehicle 100 is proposed that uses two reflections at a concave mirror. This will be described with reference to FIG. 2. Figures 2 to 3 Figure 4

[0065] Figure 4 FIG. 1 is a diagram illustrating an example of an internal configuration of a display device for a vehicle according to an aspect of the present disclosure.

[0066] Referring to FIG. 2, a display device for a vehicle 100 according to an aspect of the present disclosure can include an image generation device 300 that outputs a projected image, a concave mirror 325 that reflects the projected image, and a transparent cover 335 that transmits or reflects the projected image reflected from the concave mirror 325. The display device for a vehicle 100 can further include a motor 327 for adjusting the position of the projected image projected onto the windshield by adjusting the inclination of the concave mirror 325 to match the eye height of a user (or a driver). Figure 4 The image generation device 300 can output a projected image polarized in a certain direction. Hereinafter, the projected image output by the image generation device 300 will be referred to as a first polarized projected image. The first polarization is linear polarization, and can be, for example, P polarization. The image generation device 300 can include at least one of a liquid crystal display (LCD), an organic light emitting diode (OLED), a digital mirror device, and a micro light emitting diode (LED).

[0067] The concave mirror 325 can be disposed to lie flat so as to be inclined toward the longitudinal direction (X direction) of the vehicle. The concave mirror 325 can include a phase delay layer for converting the first polarized projected image into a second polarized projected image and converting the second polarized projected image into the first polarized projected image. The second polarization is linear polarization, and can be, for example, S polarization. The installation angle α of the concave mirror 325 with respect to the longitudinal direction (X direction) of the vehicle can be equal to or greater than 90 degrees (e.g., 90 degrees + θ).

[0068] ​​​

[0069] The phase retardation layer can be equipped as a quarter wave plate (QWP). The role of the phase retardation layer will be further described with reference to Figure 5 The role of the phase retardation layer is described. Figure 5 is a magnified cross-sectional view of a concave mirror of a display device for a vehicle in Figure 4

[0070] As shown in (5-1) in Figure 5 , first linearly polarized light (e.g., P-polarized light) irradiated to the phase retardation layer 325L can be converted into first circularly polarized light (e.g., right-handed circularly polarized light) while passing through the phase retardation layer 325L, the first circularly polarized light can be converted into second circularly polarized light (e.g., left-handed circularly polarized light) while being reflected by the reflecting layer (or reflecting surface) 325R of the concave mirror 325, and the reflected second circularly polarized light can be converted into second linearly polarized light (e.g., S-polarized light) while passing through the phase retardation layer 325L again.

[0071] On the other hand, as shown in (5-2) in Figure 5 , second linearly polarized light (e.g., S-polarized light) irradiated to the phase retardation layer 325L can be converted into second circularly polarized light (e.g., left-handed circularly polarized light) while passing through the phase retardation layer 325L, the second circularly polarized light can be converted into first circularly polarized light (e.g., right-handed circularly polarized light) while being reflected by the reflecting layer of the concave mirror 325, and the reflected first circularly polarized light can be converted into first linearly polarized light (e.g., P-polarized light) while passing through the phase retardation layer again.

[0072] Referring back to Figure 4 , the transparent cover 335 can function as a dust cover for preventing foreign substances from flowing in. The transparent cover 335 can be constructed as a flat surface or a curved surface depending on the windshield and vehicle characteristics. A polarizing layer for transmitting the first polarized light while reflecting the second polarized light can be formed on the transparent cover 335. That is, the polarizing layer can be a mirror-type polarizing layer for reflecting the second polarized light rather than absorbing the second polarized light.

[0073] The light path of the projection image via the concave mirror 325 and the transparent cover 335 and the polarization conversion of the projection image will be further described with reference to Figure 6 Figure 6 The light path of the projection image and the polarization conversion in the display device for a vehicle in Figure 4

[0074] As shown in (5-1) in Figure 6 ​​​As illustrated, the first polarization projection image (e.g., P-polarization image) output from the image generation device 300 can be converted by the concave mirror 325 into a second polarization projection image (e.g., S-polarization image) and reflected to the transparent cover 335. The conversion of the first polarization projection image into the second polarization projection image by the concave mirror 325 is as described above with reference to Figure 5 The light path of the second polarization projection image from the concave mirror 325 to the transparent cover 335 that is reflected by the concave mirror 325 once will be referred to as a first light path R1.

[0075] The second polarization projection image reflected to the transparent cover 335 can be reflected back to the concave mirror 325 by the polarization layer of the transparent cover 335. As described above, the polarization layer of the transparent cover 335 can reflect the second polarization light. The light path of the second polarization projection image from the transparent cover 335 to the concave mirror 325 that is reflected by the transparent cover 335 will be referred to as a second light path R2.

[0076] The second polarization projection image reflected by the polarization layer can be converted by the concave mirror 325 into the first polarization projection image (e.g., P-polarization image) and can be reflected back to the transparent cover 335. The conversion of the second polarization projection image into the first polarization projection image by the concave mirror 325 is as described above with reference to Figure 5 The light path of the first polarization projection image from the concave mirror 325 to the transparent cover 335 that is reflected by the concave mirror 325 twice will be referred to as a third light path R3.

[0077] The first polarization projection image reflected back to the transparent cover 335 can pass through the polarization layer of the transparent cover 335. As described above, the polarization layer of the transparent cover 335 can transmit the first polarization light therethrough.

[0078] When comparing the first light path R1, the second light path R2, and the third light path R3 to each other, the second light path R2 can be longer than the first light path R1, and the third light path R3 can be longer than the second light path R2.

[0079] Referring back to Figure 4 , the transmitted first polarization projection image is reflected in the predetermined region Arz of the windshield WS and output to the driver's line-of-sight region Ara.

[0080] As described above, because the concave mirror 325 is disposed to lie largely along the horizontal longitudinal direction (X direction) of the vehicle, even when the concave mirror 325 having a relatively large size is disposed in the display device for vehicle 100, the size in the up-down direction of the display device for vehicle 100 is not greatly affected. In addition, the display device for vehicle 100 is configured so that the projection image output from the image generation device 300 is reflected twice by the concave mirror 325 and output to the windshield WS, thereby ensuring a light path of sufficient length for the projection image. The size of the display device for vehicle 100 can be reduced to the extent that a light path of sufficient length can be ensured.

[0081] Further description will be made with reference to Figure 7 the region in which the projection image is reflected once in the concave mirror 325 (hereinafter, referred to as a first mirror reflection region) and the region in which the projection image is reflected twice in the concave mirror 325 (hereinafter, referred to as a second mirror reflection region), and the region in which the projection image is reflected in the transparent cover 335 in the display device for vehicle 100 according to Figure 4 the region in which the projection image is transmitted (hereinafter, referred to as a cover transmission region). Figure 7 are diagrams for illustrating the reflection region and the transmission region in the display device for vehicle in Figure 4

[0082] As shown in Figure 7 , the projection image output from the image generation device 300 can be reflected by the first mirror reflection region 325-1 of the concave mirror 325 to the transparent cover 335. The first mirror reflection region 325-1 can be a region that is biased toward the front of the vehicle within the entire region of the concave mirror 325. The projection image reflected by the first mirror reflection region can be guided to the transparent cover 335.

[0083] The projection image guided to the transparent cover 335 can be reflected by the cover reflection region 335-1 of the transparent cover 335 to the concave mirror 325. The cover reflection region 335-1 can be a region that is biased toward the front of the vehicle within the entire region of the transparent cover 335. The projection image reflected by the cover reflection region 335-1 can be guided to the concave mirror 325.

[0084] ​The projected image guided to the concave mirror 325 can be reflected onto the transparent cover 335 via the secondary mirror reflection area 325-2 of the concave mirror 325. The secondary mirror reflection area 325-2 can be a region offset towards the rear of the vehicle within the entire area of ​​the concave mirror 325. The secondary mirror reflection area 325-2 can partially overlap with the primary mirror reflection area 325-1. The secondary mirror reflection area 325-2 can be wider than the primary mirror reflection area 325-1. Depending on the design, the secondary mirror reflection area 325-2 can completely encompass the primary mirror reflection area 325-1.

[0085] The projected image guided to the transparent cover 335 can pass through the cover-transmitting region 335-2 of the transparent cover 335. The cover-transmitting region 335-2 can be an area offset towards the rear of the vehicle within the entire area of ​​the transparent cover 335. The cover-transmitting region 335-2 can partially overlap with the cover-reflecting region 335-1. The cover-transmitting region 335-2 can be wider than the cover-reflecting region 335-1. Depending on the design, the cover-transmitting region 335-2 can completely encompass the cover-reflecting region 335-1.

[0086] As described above, the transmitted projected image is reflected in a predetermined area Arz of the windshield WS and output to the driver's line of sight area Ara.

[0087] In the following text, reference will be made to Figure 8 describe Figure 4 The optical path for projected images in a vehicle display device. Figure 8 It is used for example Figure 4 A diagram of the optical path of the projected image used in a display device for a vehicle.

[0088] The projected image output from the image generating device 300 can be reflected once from the concave mirror 325 onto the transparent cover 335.

[0089] The projected image, after one reflection, can be reflected by the transparent cover 335 to the concave mirror 325.

[0090] The projected image guided to the concave mirror 325 can be reflected a second time to the transparent cover 335 by the concave mirror 325.

[0091] The projected image, after secondary reflection, can pass through the transparent cover 335.

[0092] The projected image transmitted through the windshield can be reflected in a predetermined area Arz of the windshield WS and output to the driver's line of sight area Ara.

[0093] Therefore, the projected image can be observed by the driver as a virtual image on the opposite side of the windshield WS (i.e., outside the windshield WS).

[0094] In the following text, refer toFigure 9 , according to Figure 3 a display device 100y for a vehicle according to Figure 4 the sizes of the display devices for a vehicle according to Figure 9 are compared with each other. Figure 3 is a diagram for comparing the sizes of the display devices for a vehicle in Figure 4

[0095] Figure 9 (9-1) in illustrates a partial cross-sectional view of a vehicle 200 in which a display device 100y for a vehicle according to Figure 3 is installed. Figure 9 (9-2) in illustrates a partial cross-sectional view of a vehicle 200 in which a display device 100 for a vehicle according to Figure 4 is installed.

[0096] As shown in Figure 9 , the display devices for a vehicle 100 and 100y for installation in a vehicle can be adjacent to a brake structure 210, a steering wheel structure 220, a HUD frame 230, and the like.

[0097] It can be seen that the display device for a vehicle 100 according to Figure 4 has a smaller size than the display device for a vehicle 100y according to Figure 3 , so that the volume occupied by the display device can be greatly reduced. That is, as shown in Figure 9 (9-2), the volume can be reduced by the area S indicated by the hatching. This is because, as described above, the display device for a vehicle 100 is configured so that not only is the concave mirror 325 disposed to lie flat so as to be inclined toward the longitudinal direction (X direction) of the vehicle, but also the projected image is reflected twice by the concave mirror 325 and does not require the flat mirror 315y. For these reasons, it is apparent that the display device for a vehicle 100 according to Figure 4 is also smaller in size than the display device for a vehicle 100x according to Figure 2 .

[0098] In one example, in order to prevent damage caused by sunlight, a heat-blocking film can be applied to the front end of the image generation device, the concave mirror, or the dust cover. In addition, the posture of each optical component can be changed depending on the windshield WS of the vehicle and the installation space of the display device for a vehicle, and the virtual image distance and the field of view (FOV) can also be changed as needed.

[0099] ​The above detailed description should not be interpreted as including all aspects of the disclosure which are implied but not expressly stated or potentially implied by the above detailed description. The scope of the disclosure should be determined by a fair reading of the appended claims in light of the full disclosure and understood to include all changes which come within the meaning and range of equivalency of the claims.

Claims

1. A display device for a vehicle, the display device comprising: An image generating apparatus configured to output a first polarization projection image; A concave mirror, the concave mirror including a phase retardation layer for polarization conversion between a first polarized light and a second polarized light; as well as A transparent cover, comprising a polarizing layer for allowing the first polarized light to pass through and reflecting the second polarized light. The concave mirror is configured to convert the first polarized projection image output from the image generating device into a second polarized projection image, and to reflect the second polarized projection image onto the transparent cover in one pass. The transparent cover is configured to reflect the second polarized projection image onto the concave mirror. The concave mirror is configured to convert the second polarization projection image into the first polarization projection image, and to reflect the first polarization projection image a second time back onto the transparent cover. The transparent cover is configured to allow the first polarized projection image to be transmitted through it.

2. The display device according to claim 1, further comprising a motor configured to adjust the position of the first polarized projection image passing through the transparent cover.

3. The display device according to claim 1, wherein, The primary mirror reflection area of ​​the concave mirror is located closer to the front of the vehicle than the secondary mirror reflection area of ​​the concave mirror.

4. The display device according to claim 3, wherein, The primary mirror reflection region is narrower than the secondary mirror reflection region.

5. The display device according to claim 1, wherein, The reflective area of ​​the transparent cover is positioned closer to the front of the vehicle than the transmissive area of ​​the transparent cover.

6. The display device according to claim 5, wherein, The reflective area of ​​the cover is narrower than the transmissive area of ​​the cover.

7. The display device according to claim 1, wherein, The first polarized light is P-polarized light and the second polarized light is S-polarized light.

8. The display device according to claim 1, wherein, The image generation device includes one of a liquid crystal display (LCD), an organic light-emitting diode (OLED), a digital mirror device, and a micro light-emitting diode (LED).

9. The display device according to claim 1, wherein, The phase delay layer includes a quarter-wave plate.

10. The display device according to claim 1, wherein, The first optical path from the concave mirror to the transparent cover of the second polarized projection image after one reflection is shorter than the second optical path from the transparent cover to the concave mirror of the second polarized projection image reflected by the transparent cover.

11. The display device according to claim 10, wherein, The second optical path is shorter than the third optical path from the concave mirror to the transparent cover of the first polarized projection image after secondary reflection.

12. The display device according to claim 1, wherein, The second polarized projection image, passing through the transparent cover, is projected onto the windshield of the vehicle.

13. The display device according to claim 1, wherein, The display device used in the vehicle includes a head-up display (HUD).

Images