Optical element, transparent display screen, vehicle-mounted display system and head-up display system

Abstract

The utility model discloses an optical element, a transparent display screen, a vehicle-mounted display system and a head-up display system, and the optical element is used for receiving projection image light, and comprises a first light transmitting region corresponding to a first incident angle range of the projection image light; the second light-transmitting area corresponds to a second incident angle range of the projected image light; wherein the incident angle value corresponding to the first incident angle range is greater than the incident angle value corresponding to the second incident angle range, and the light transmissivity of the projected image of the first light-transmitting area is greater than the light transmissivity of the projected image of the second light-transmitting area. The projection image light transmissivity of the areas corresponding to different incident angles is different, so that the overall transmissivity of the projection image light on the incident surface can be improved, the Fresnel loss of the projection image light on the incident surface is further reduced, the light is prevented from being reflected into the projector, the performance of the projector is improved, the service life of the projector is prolonged, and the production cost is reduced. Therefore, the normal working requirement of the vehicle-mounted display system is met.

Description

Technical Field

[0001] The present application relates to the field of display, and in particular to optical elements, transparent display screens, vehicle-mounted display systems, and head-up display systems. Background Art

[0002] As cars become more intelligent, in-vehicle display systems are increasingly being used in cars, including window projection display systems and head-up display systems (HUD).

[0003] In the prior art, in a car window projection display system, the viewer and the projector are located on both sides of the projection screen (car window glass), and the image is viewed through the projection image light transmitted from the car window glass by the projector. In a head-up display system, the viewer and the projector are located on the same side of the projection screen (front windshield), and the projection image light of the projector is first incident on a piece of car window glass, and the reflective layer in the car window glass then reflects the projection image light to the front windshield, so as to be displayed through the front windshield.

[0004] However, when the projected image light is incident on the car window glass or windshield, there is Fresnel reflection on the incident surface of the glass, and the Fresnel reflection changes with the incident angle. When the incident angle is large, the Fresnel reflection is very obvious, which not only reduces the transmittance of the projected image light on the incident surface, but also part of the light reflected by Fresnel may enter the projector, causing the internal temperature of the projector to soar, affecting the performance and service life of the projector, and thus failing to meet the normal working requirements of the vehicle display system. Utility Model Content

[0005] The main technical problem solved by the present application is to provide optical elements, transparent display screens, vehicle-mounted display systems and head-up display systems, which can solve the problem that existing vehicle window glass or windshield cannot meet the normal working requirements of the vehicle-mounted display system.

[0006] In order to solve the above-mentioned technical problems, the first technical solution adopted in the present application is to provide an optical element for receiving projection image light, including: a first light-transmitting area, corresponding to a first incident angle range of the projection image light; a second light-transmitting area, corresponding to a second incident angle range of the projection image light; wherein the incident angle value corresponding to the first incident angle range is greater than the incident angle value corresponding to the second incident angle range, and the projection image light transmittance of the first light-transmitting area is greater than the projection image light transmittance of the second light-transmitting area.

[0007] Among them, the first incident angle range includes multiple first sub-incident angle ranges, each first sub-incident angle range corresponds to a first sub-light-transmitting area in the first light-transmitting area; wherein different first sub-light-transmitting areas corresponding to different first sub-incident angle ranges have different projection image light transmittances; the second incident angle range includes multiple second sub-incident angle ranges, each second sub-incident angle range corresponds to a second sub-light-transmitting area in the second light-transmitting area; wherein different second sub-light-transmitting areas corresponding to different second sub-incident angle ranges have different projection image light transmittances.

[0008] Among them, the first incident angle range is 60° to 80°, and multiple first sub-incident angle ranges are between 60° and 80°; the second incident angle range is 15° to 60°, and multiple second sub-incident angle ranges are between 15° and 60°.

[0009] Among them, each first sub-light-transmitting area is provided with one of a first combined film layer, a first dielectric layer and a first porous material layer; the first combined film layer, the first dielectric layer and the first porous material layer are respectively used to transmit the projection image light corresponding to the first sub-incident angle range; each second sub-light-transmitting area is provided with one of a second combined film layer, a second dielectric layer and a second porous material layer; the second combined film layer, the second dielectric layer and the second porous material layer are respectively used to transmit the projection image light corresponding to the second sub-incident angle range.

[0010] Among them, the total number of film layers in the first combination of film layers is different from the total number of film layers in the second combination of film layers; and / or the thickness of at least one anti-reflection film in the first combination of film layers is different from the thickness of at least one anti-reflection film in the second combination of film layers; and / or the refractive index of at least one anti-reflection film in the first combination of film layers is different from the refractive index of the multiple anti-reflection films in the second combination of film layers.

[0011] The first light-transmitting area and the second light-transmitting area are spliced ​​to form a light-receiving surface of the optical element, and a splicing line between the first light-transmitting area and the second light-transmitting area is a straight line or an arc.

[0012] In order to solve the above technical problems, the second technical solution adopted in the present application is to provide a transparent display screen, including a screen body, and the screen body is composed of the above optical elements.

[0013] In order to solve the above technical problems, the third technical solution adopted in this application is to provide a vehicle-mounted display system, including a projector and a screen, and the screen is the above-mentioned transparent display screen.

[0014] The screen is a car window glass or a windshield.

[0015] In order to solve the above-mentioned technical problems, the fourth technical solution adopted in the present application is to provide a head-up display system, including an image display unit, the image display unit includes a projector and a reflective element, the reflective element includes a light-receiving surface facing the projection direction of the projector and a reflective surface opposite to the light-receiving surface, the reflective surface is formed with a reflective layer, and the light-receiving surface is formed with an optical element as mentioned above, the projection image light projected by the projector is irradiated to the reflective element, is transmitted from the light-receiving surface of the reflective element to the reflective surface, and is reflected to the display medium via the reflective surface.

[0016] The beneficial effect of the present application is as follows: Different from the prior art, the present application provides an optical element, a transparent display screen, a vehicle-mounted display system and a head-up display system. By setting a first light-transmitting area and a second light-transmitting area corresponding to different incident angle ranges on the optical element, and making the projected image light transmittances of the areas corresponding to different incident angles different, the overall transmittance of the projected image light on the incident surface can be improved, thereby reducing the Fresnel loss of the projected image light on the incident surface, avoiding light reflection into the interior of the projector, thereby improving the performance and service life of the projector, and then meeting the normal working requirements of the vehicle-mounted display system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 It is a structural schematic diagram of an implementation scheme of a vehicle window projection display system of the present application;

[0019] Figure 2 yes Figure 1 A cross-sectional schematic diagram of the center window projection display system;

[0020] Figure 3 This is the relationship between Fresnel reflectivity and incident angle;

[0021] Figure 4 yes Figure 1 The incident angles corresponding to the multiple marking points of the optical element;

[0022] Figure 5 for Figure 1 Fresnel reflectivity corresponding to multiple marking points of the optical element;

[0023] Figure 6 It is a structural schematic diagram of an embodiment of an optical element of the present application;

[0024] Figure 7 yes Figure 6Schematic cross-sectional view of the optical element;

[0025] Figure 8 This is a schematic structural diagram of another embodiment of the optical element of the present application;

[0026] Fig. 9 It is a structural schematic diagram of an implementation scheme of a head-up display system of the present application;

[0027] Fig.10 yes Fig. 9 A schematic structural diagram of an embodiment of a reflective element. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0029] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms of "a", "said", and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless otherwise clearly indicated above, and "multiple" generally includes at least two, but does not exclude the inclusion of at least one.

[0030] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0031] It should be understood that the terms "include", "comprises" or any other variations used herein are intended to cover non-exclusive inclusion, so that a process, method, article or device that includes a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of more restrictions, the elements defined by the sentence "includes..." do not exclude the presence of other identical elements in the process, method, article or device that includes the elements.

[0032] The present application first provides a vehicle window projection display system.

[0033] Specifically, see Figure 1 and Figure 2 , Figure 1is a structural schematic diagram of an embodiment of the vehicle window projection display system of the present application, Figure 2 yes Figure 1 Cross-sectional diagram of the mid-window projection display system.

[0034] In this embodiment, the vehicle window projection display system 100 includes a projector 20 and a screen, and the screen is a transparent display screen. The transparent display screen includes a screen body, and the screen body is composed of an optical element 10. The screen is used to receive the projection image light for display. Specifically, the light incident surface of the optical element 10 is used to transmit the projection image light emitted by the projector 20, and the light emitting surface of the optical element 10 is used to emit the projection image light for display.

[0035] In this embodiment, the screen is a car window glass or a windshield.

[0036] In this embodiment, there is a fixed distribution relationship between the projector 20 and the optical element 10. In some embodiments, the horizontal distance between the projector 20 and the optical element 10 is a, the vertical distance between the projector 20 and the lower end of the optical element 10 is b, and the vertical distance between the projector 20 and the upper end of the optical element 10 is c.

[0037] In this embodiment, under a fixed distribution relationship, the projection image light emitted by the projector 20 has different incident angles when reaching different positions of the optical element 10 , and has different Fresnel reflections at different positions.

[0038] In some implementations, see Figure 1 The optical element 10 includes 15 marking points, namely S1 to S 15 , multiple marking points are used to locate different areas of the optical element 10. In some specific embodiments, multiple marking points are arranged in an array to form a marking point matrix, wherein the distance between two adjacent marking points in the same row is equal, and the distance between two adjacent marking points in the same column is equal.

[0039] The incident angles of the projection image light emitted by the projector 20 at the 15 marking points are different, and the Fresnel reflection changes with the incident angle. When the incident angle is large, the Fresnel reflection is very obvious.

[0040] For details, please refer to Figure 3 , Figure 4 and Figure 5 , Figure 3 This is the relationship between Fresnel reflectivity and incident angle. Figure 4 yes Figure 1 The incident angles corresponding to the multiple marking points of the optical element, Figure 5 for Figure 1 Fresnel reflectivity corresponding to multiple marked points of the optical element in FIG.

[0041] Depend on Figure 3It can be seen that when the incident angle is greater than 60°, the Fresnel reflection corresponding to the P polarized light (Rp), the Fresnel reflection corresponding to the S polarized light (Rs) and the Fresnel reflection corresponding to the full light (R) all increase significantly. 11 and the marker point S 15 At the point S, the incident angle γ of the projected image light is the largest, which is 75°; at the marked point S3, the incident angle δ of the projected image light is the smallest, which is 25°; the incident angles at the remaining marked points are between 25° and 75°, and most of them are greater than 60°, and only the incident angles at the marked points S2 and S4 are close to 50°. 11 and the marker point S 15 At point S3, Rp, Rs and R are all relatively large, while at point S4, Rp, Rs and R are all relatively small.

[0042] In this embodiment, in order to suppress Fresnel reflection, multiple light-transmitting areas are set for different incident angle ranges, and the projected image light transmittances of the areas corresponding to different incident angles are made different, so as to improve the overall transmittance of the projected image light on the incident surface, thereby reducing the Fresnel loss of the projected image light on the incident surface.

[0043] Specifically, see Figure 6 , Figure 6 It is a schematic structural diagram of an embodiment of an optical element of the present application.

[0044] In this embodiment, the optical element 10 includes a first light-transmitting area 11 and a second light-transmitting area 12. The first light-transmitting area 11 corresponds to a first incident angle range of the projected image light, and the second light-transmitting area 12 corresponds to a second incident angle range of the projected image light. The incident angle value corresponding to the first incident angle range is greater than the incident angle value corresponding to the second incident angle range, and the projected image light transmittance of the first light-transmitting area 11 is greater than the projected image light transmittance of the second light-transmitting area 12.

[0045] In some embodiments, the optical element 10 includes a transparent substrate 13 having a first surface and a second surface opposite to each other, and the first light-transmitting area 11 and the second light-transmitting area 12 are disposed on the first surface of the transparent substrate 13. In some specific embodiments, the transparent substrate 13 is a vehicle window glass.

[0046] In this embodiment, the first incident angle range includes a plurality of first sub-incident angle ranges, each of which corresponds to a first sub-light-transmitting area in the first light-transmitting area 11. The projected image light transmittances of different first sub-light-transmitting areas corresponding to different first sub-light-transmitting areas are different. The second incident angle range includes a plurality of second sub-incident angle ranges, each of which corresponds to a second sub-light-transmitting area in the second light-transmitting area 12. The projected image light transmittances of different second sub-light-transmitting areas corresponding to different second sub-incident angle ranges are different.

[0047] In some embodiments, the first incident angle range is 60° to 80°, and the first sub-incident angle ranges are between 60° and 80°. The second incident angle range is 15° to 60°, and the second sub-incident angle ranges are between 15° and 60°.

[0048] In some specific embodiments, the first light-transmitting area 11 includes marking points S6 to S 10 The located upper area and the marking point S 11 ~S 15 The entire area located, the second light-transmitting area 12 includes the marking points S6 to S 10 The lower part of the area located and the entire area located by the marking points S1 to S5, combined with Figure 4 and Figure 6 It can be seen that the incident angle range corresponding to each area of ​​the first light-transmitting area 11 is 60° to 75°, and the incident angle range corresponding to each area of ​​the second light-transmitting area 12 is 25° to 60°.

[0049] In some specific embodiments, Figure 6 As shown, the first light-transmitting area 11 includes three first sub-light-transmitting areas 11a, 11b, and 11c. The first sub-light-transmitting area 11a corresponds to the marking points S6 and S7 at the left end. 11 The first sub-light-transmitting area 11a corresponds to a first sub-incident angle range of about 70° to 75°; the first sub-light-transmitting area 11b corresponds to the middle marking points S7 to S9 and S 12 ~S 14 , the first sub-light-transmitting area 11b corresponds to a first sub-incident angle range of about 60° to 70°; the first sub-light-transmitting area 11c corresponds to the marking point S at the right end 10 With S 15 , the first sub-light-transmitting area 11c corresponds to a first sub-incident angle range of about 70° to 75°. The second light-transmitting area 12 includes three second sub-light-transmitting areas 12a, 12b, and 12c. The second sub-light-transmitting area 12a corresponds to the marking points S1 and S6 at the left end, and the second sub-incident angle range corresponding to the second sub-light-transmitting area 12a is about 50° to 60°; the second sub-light-transmitting area 12b corresponds to the marking points S2 to S4 and S7 to S9 in the middle, and the second sub-incident angle range corresponding to the second sub-light-transmitting area 12b is about 25° to 50°; the second sub-light-transmitting area 12c corresponds to the marking points S5 and S6 at the right end. 10 The second sub-incident angle range corresponding to the second sub-light-transmitting area 12c is approximately 50° to 60°.

[0050] It can be understood that the first incident angle range is 60° to 80°, which can cover the incident angle values ​​corresponding to each first sub-light-transmitting area in the first light-transmitting area 11 of the projected image light. Similarly, the second incident angle range is 15° to 60°, which can cover the incident angle values ​​corresponding to each second sub-light-transmitting area in the second light-transmitting area 12 of the projected image light.

[0051] In other implementations, the first incident angle range may also be 70° to 80°, and the second incident angle range may be 15° to 70°.

[0052] In some other embodiments, the first incident angle range may be 50° to 80°, and the second incident angle range may be 15° to 50°. Correspondingly, the splicing line between the first light-transmitting area 11 and the second light-transmitting area 12 is located at the lower part of the optical element 10, so that the area of ​​the first light-transmitting area 11 is larger than the area of ​​the second light-transmitting area 12.

[0053] In this embodiment, the first light-transmitting area 11 and the second light-transmitting area 12 are spliced ​​to form the light-receiving surface of the optical element 10, and the splicing line between the first light-transmitting area 11 and the second light-transmitting area 12 is a straight line or an arc. Figure 6 As shown in FIG. 1 , the splicing line of the first light-transmitting area 11 and the second light-transmitting area 12 is a straight line. In other embodiments, the splicing line of the first light-transmitting area 11 and the second light-transmitting area 12 is an arc line, such as Figure 8 As shown, Figure 8 It is a schematic structural diagram of another embodiment of the optical element of the present application.

[0054] The above implementation only provides some partitioning methods (all of which are horizontal partitioning), and more partitioning methods can be set according to actual conditions. For example, in other implementations, it can be divided into two vertical areas, or into two diagonal areas, or into two areas formed arbitrarily.

[0055] In some specific embodiments, the first sub-light-transmitting regions in the first light-transmitting region 11 can be spliced ​​in the horizontal, vertical, oblique or arbitrary directions, and the first sub-light-transmitting regions can have any shape. Similarly, the second sub-light-transmitting regions in the second light-transmitting region 12 can be spliced ​​in the horizontal, vertical, oblique or arbitrary directions, and the second sub-light-transmitting regions can have any shape, which is not limited in the present application.

[0056] In this embodiment, each first light transmission sub-area is provided with one of a first combined film layer, a first dielectric layer and a first porous material layer, which are respectively used to transmit projection image light corresponding to the first sub-incident angle range.

[0057] In this embodiment, each second light-transmitting sub-area is provided with one of a second combined film layer, a second dielectric layer and a second porous material layer, which are respectively used to transmit projection image light corresponding to the second sub-incident angle range.

[0058] In some embodiments, the first combined film layer and the second combined film layer both include a stacked multilayer antireflection film, and the refractive index of two adjacent layers of antireflection film is different. The refractive index and thickness of the multilayer antireflection film in the first combined film layer meet the condition of transmitting the projection image light in the corresponding first sub-incident angle range. The refractive index and thickness of the multilayer antireflection film in the second combined film layer meet the condition of transmitting the projection image light in the corresponding second sub-incident angle range.

[0059] In some specific implementations, the antireflection film can be magnesium fluoride (MgF), titanium dioxide (TiO2), silicon dioxide (SiO2), aluminum oxide (Al2O3), etc.

[0060] In some implementations, the first dielectric layer and the second dielectric layer are dielectric films, and the thickness of the dielectric films is adjusted so that the refractive index satisfies the condition of transmitting the projection image light in the corresponding first sub-incident angle range or second sub-incident angle range.

[0061] In some embodiments, the dielectric film can be an anti-reflective dielectric film layer that allows light to be transmitted through the optical surface to a greater extent by reducing the reflectivity of the surface to near zero.

[0062] In some embodiments, the first porous material layer and the second porous material layer are low-density and low-refractive-index porous materials, and the thickness of the porous material layer is adjusted so that the refractive index satisfies the condition of transmitting the projection image light in the corresponding first sub-incident angle range or the second sub-incident angle range.

[0063] In some specific embodiments, the porous material can be an organic polymer such as a thermoplastic material and a cross-linked polymer, an organic-inorganic polymer, an inorganic polymer such as a low melting point inorganic glass, etc., for example, a nanoporous silica film, an organic polysilica resin, etc., which is not limited in the present application.

[0064] In some embodiments, the first light-transmitting sub-regions in the first light-transmitting region 11 may all be provided with a first combined film layer, or may all be provided with a first dielectric layer, or may all be provided with a first porous material layer. In other embodiments, some of the first light-transmitting sub-regions may be provided with a first combined film layer, and the remaining first light-transmitting sub-regions may be provided with a first dielectric layer or a first porous material layer. In still other embodiments, some of the first light-transmitting sub-regions may be provided with a first combined film layer, some of the first light-transmitting sub-regions may be provided with a first dielectric layer, and the remaining first light-transmitting sub-regions may be provided with a first porous material layer, which is not limited in the present application.

[0065] In some embodiments, the second light-transmitting sub-regions in the second light-transmitting region 12 may all be provided with a second combined film layer, or may all be provided with a second dielectric layer, or may all be provided with a second porous material layer. In other embodiments, some of the second light-transmitting sub-regions may be provided with a second combined film layer, and the remaining second light-transmitting sub-regions may be provided with a second dielectric layer or a second porous material layer. In still other embodiments, some of the second light-transmitting sub-regions may be provided with a second combined film layer, some of the second light-transmitting sub-regions may be provided with a second dielectric layer, and the remaining second light-transmitting sub-regions may be provided with a second porous material layer, which is not limited in the present application.

[0066] Please refer to Figure 7 , Figure 7 yes Figure 6 In this embodiment, the first light-transmitting area 11 is provided with a first combined film layer 30 , and the second light-transmitting area 12 is provided with a second combined film layer 40 .

[0067] In this embodiment, the first combined film layer 30 and the second combined film layer 40 both include stacked multilayer antireflection films, and the refractive indexes of two adjacent antireflection films are different. The refractive index and thickness of the multilayer antireflection films in the first combined film layer 30 meet the condition of transmitting the projection image light in the first incident angle range, and the refractive index and thickness of the multilayer antireflection films in the second combined film layer 40 meet the condition of transmitting the projection image light in the second incident angle range.

[0068] In some embodiments, two adjacent antireflection films are made of different optical coating materials. In some specific embodiments, the optical coating material may be magnesium fluoride (MgF), titanium dioxide (TiO2), silicon dioxide (SiO2), aluminum oxide (Al2O3), etc.

[0069] In some embodiments, the total number of film layers in the first combined film layer 30 is different from the total number of film layers in the second combined film layer 40. In other embodiments, the thickness of at least one anti-reflection film in the first combined film layer 30 is different from the thickness of at least one anti-reflection film in the second combined film layer 40. In still other embodiments, the refractive index of at least one anti-reflection film in the first combined film layer 30 is different from the refractive index of the multiple anti-reflection films in the second combined film layer 40.

[0070] In some specific implementations, the total number of film layers, the thickness of each anti-reflection film, and the refractive index of the first combined film layer 30 may be different from those of the second combined film layer 40 , or may be partially the same.

[0071] In a specific implementation scenario, such as Figure 7As shown, the first combined film layer 30 is arranged on the first light-transmitting area 11 of the transparent substrate 13. The first combined film layer 30 is sequentially stacked with four anti-reflection films along the thickness direction of the transparent substrate 13, namely, the first anti-reflection film 31, the second anti-reflection film 32, the third anti-reflection film 33 and the fourth anti-reflection film 34. The first anti-reflection film 31 and the third anti-reflection film 33 are both TiO2, the second anti-reflection film 32 and the fourth anti-reflection film 34 are both MgF, the first anti-reflection film 31 has a thickness of 12nm, the second anti-reflection film 32 has a thickness of 32nm, the third anti-reflection film 33 has a thickness of 114nm, and the fourth anti-reflection film 34 has a thickness of 115nm. The first combined film layer 30 can meet the condition of transmitting 60° to 80° of the projected image light. The second combined film layer 40 is disposed on the second light-transmitting area 12 of the transparent substrate 13. The second combined film layer 40 is sequentially stacked with four anti-reflection films along the thickness direction of the transparent substrate 13, namely, the fifth anti-reflection film 41, the sixth anti-reflection film 42, the seventh anti-reflection film 43 and the eighth anti-reflection film 44. The fifth anti-reflection film 41 and the seventh anti-reflection film 43 are both TiO2, the sixth anti-reflection film 42 and the eighth anti-reflection film 44 are both MgF, the fifth anti-reflection film 41 has a thickness of 23nm, the sixth anti-reflection film 42 has a thickness of 23nm, the seventh anti-reflection film 43 has a thickness of 84nm, and the eighth anti-reflection film 44 has a thickness of 131nm. The second combined film layer 40 can meet the condition of transmitting 15° to 60° of projection image light.

[0072] In another specific implementation scenario, the first combined film layer 30 is disposed on the first light-transmitting area 11 of the transparent substrate 13, and the first combined film layer 30 is sequentially stacked with two layers of anti-reflection films along the thickness direction of the transparent substrate 13, wherein the first anti-reflection film is MgF, the second anti-reflection film is TiO2, the thickness of the first anti-reflection film is 233nm, and the thickness of the second anti-reflection film is 62nm. The first combined film layer 30 can meet the conditions of transmitting 60° to 80° projection image light. The second combined film layer 40 is disposed on the first light-transmitting area 11 of the transparent substrate 13, and the second combined film layer 40 is sequentially stacked with three layers of anti-reflection films along the thickness direction of the transparent substrate 13, wherein the first anti-reflection film and the third anti-reflection film are both TiO2, the second anti-reflection film is MgF, the thickness of the first anti-reflection film is 9nm, the thickness of the second anti-reflection film is 86nm, and the thickness of the third anti-reflection film is 8nm. The second combined film layer 40 can meet the condition of transmitting the projection image light of 15° to 60°.

[0073] In actual production, the inventor of the present application found that when an integral transmission film is provided on the transparent display screen, the projected image light at the mark point S 11 and the marker point S 15 The transmittance at the point S (incident angle of 75°) is lower than 84%. After the first combined film layer 30 and the second combined film layer 40 are arranged in different zones for different incident angles, the projected image light is projected at the marked point S11 and the marker point S 15 The transmittance at the first light-transmitting area 11 (incident angle of 75°) is 87%, the transmittance of the projection image light in the remaining areas of the first light-transmitting area 11 is between 87% and 94%, and the transmittance of the projection image light in the second light-transmitting area 12 is between 91% and 99%.

[0074] It can be understood that by partitioning and setting multiple combined film layers for different incident angles, not only the difficulty of setting and the preparation cost of each combined film layer can be reduced, but also the reliability and anti-reflection effect of each combined film layer can be improved.

[0075] Further, in some embodiments, in response to the first light-transmitting area 11 including a plurality of first sub-light-transmitting areas, and the second light-transmitting area 12 including a plurality of second sub-light-transmitting areas, the first combined film layer 30 includes a plurality of corresponding first sub-combined film layers, and different first sub-combined film layers are disposed in different first sub-light-transmitting areas. The second combined film layer 40 includes a plurality of corresponding second sub-combined film layers, and different second sub-combined film layers are disposed in different second sub-light-transmitting areas.

[0076] It can be understood that by respectively setting corresponding first sub-combination film layers according to the multiple first sub-light-transmitting areas of the first light-transmitting area 11, and respectively setting corresponding second sub-combination film layers according to the multiple second sub-light-transmitting areas of the second light-transmitting area 12, the film layer structure of different partitions can be further refined to better improve the transmittance of the projected image light within the corresponding incident angle, thereby further reducing the Fresnel loss to avoid light reflection into the interior of the projector 20, thereby improving the performance and service life of the projector 20, and then meeting the normal working requirements of the window projection display system 100.

[0077] Different from the prior art, this embodiment can improve the overall transmittance of the projected image light on the incident surface by setting the first light-transmitting area 11 and the second light-transmitting area 12 corresponding to different incident angle ranges on the optical element 10, and making the projected image light transmittances of the areas corresponding to different incident angles different, thereby reducing the Fresnel loss of the projected image light on the incident surface, avoiding the reflection of light into the projector 20, thereby improving the performance and service life of the projector 20, and then meeting the normal working requirements of the vehicle display system 100. Furthermore, by setting multiple combined film layers, multiple dielectric layers or porous material layers for different incident angles in a partitioned manner, not only can the setting difficulty and preparation cost of each anti-reflection film system be reduced, but also the reliability and anti-reflection effect of each anti-reflection film system can be improved.

[0078] Correspondingly, the present application provides an optical element and a head-up display system.

[0079] Specifically, see Fig. 9 and Fig.10 , Fig. 9is a structural diagram of an embodiment of a head-up display system of the present application, Fig.10 yes Fig. 9 A schematic structural diagram of an embodiment of a reflective element.

[0080] In this embodiment, the head-up display system 200 includes an image display unit, which includes a projector 20 and a reflective element 60. The reflective element 60 includes a light-receiving surface facing the projection direction of the projector 20 and a reflective surface opposite to the light-receiving surface, the reflective surface is formed with a reflective layer 62, and the light-receiving surface is formed with the above-mentioned optical element, the projection image light projected by the projector 20 is irradiated to the reflective element 60, is transmitted from the light-receiving surface of the reflective element 60 to the reflective surface, and is reflected to the display medium 50 via the reflective surface.

[0081] The display medium 50 is a head-up display glass.

[0082] There is a fixed distribution relationship between the projector 20 and the reflective element 60. Under the fixed distribution relationship, the projection image light emitted by the projector 20 has different incident angles when reaching different positions of the reflective element 60, and has different Fresnel reflections at different positions.

[0083] In some embodiments, the reflective element 60 includes 15 marking points, namely S1 to S2. 15 , multiple marking points are used to locate different areas of the reflective element 60. The incident angles of the projection image light emitted by the projector 20 at the 15 marking points are different, and the Fresnel reflection changes with the change of the incident angle. When the incident angle is large, the Fresnel reflection is very obvious. For details, please refer to Figure 3 , Figure 4 and Figure 5 .

[0084] In this embodiment, the reflective element 60 includes a first light-transmitting area 11 and a second light-transmitting area 12. The first light-transmitting area 11 corresponds to a first incident angle range of the projected image light, and the second light-transmitting area 12 corresponds to a second incident angle range of the projected image light. The incident angle value corresponding to the first incident angle range is greater than the incident angle value corresponding to the second incident angle range, and the projected image light transmittance of the first light-transmitting area 11 is greater than the projected image light transmittance of the second light-transmitting area 12.

[0085] In some embodiments, the reflective element 60 includes a transparent substrate 61 having a light receiving surface and a light emitting surface opposite to each other. The light receiving surface is provided with a first light transmitting area 11 and a second light transmitting area 12 , and the light emitting surface is provided with a reflective layer 62 .

[0086] In some specific embodiments, the first light-transmitting area 11 is provided with a first combined film layer 30 for transmitting the projection image light in the first incident angle range. The second light-transmitting area 12 is provided with a second combined film layer 40, and the second combined film layer 40 is used to transmit the projection image light in the second incident angle range. The first combined film layer 30 and the second combined film layer 40 have different film layer structures.

[0087] It can be understood that by setting the first light-transmitting area 11 and the second light-transmitting area 12 corresponding to different incident angle ranges on the reflective element 60, and setting the first combined film layer 30 and the second combined film layer 40 with different film layer structures on the first light-transmitting area 11 and the second light-transmitting area 12, respectively, the projection image light of different incident angle ranges can be transmitted through the first combined film layer 30 and the second combined film layer 40, respectively, thereby improving the transmittance of the projection image light at different positions of the incident surface. Further, by setting multiple combined film layers for different incident angles in different zones, not only can the setting difficulty and preparation cost of each combined film layer be reduced, but also the reliability and anti-reflection effect of each combined film layer can be improved. Further, by improving the overall transmittance of the projection image light on the incident surface, the Fresnel loss of the projection image light on the incident surface can be reduced, and the light reflection into the projector 20 can be avoided, thereby improving the performance and service life of the projector 20, and then meeting the normal working requirements of the head-up display system 200.

[0088] Different from the prior art, the present application arranges a first light-transmitting area and a second light-transmitting area corresponding to different incident angle ranges on an optical element or a reflective element, and makes the projected image light transmittances of the areas corresponding to different incident angles different, thereby improving the overall transmittance of the projected image light on the incident surface, thereby reducing the Fresnel loss of the projected image light on the incident surface, avoiding light reflection into the interior of the projector, thereby improving the performance and service life of the projector, and then meeting the normal working requirements of the vehicle display system.

[0089] The above description is only an implementation method of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. An optical element for receiving projection image light, characterized in that: include: A first light-transmitting area corresponds to a first incident angle range of the projection image light; A second light-transmitting area corresponding to a second incident angle range of the projection image light; The incident angle value corresponding to the first incident angle range is greater than the incident angle value corresponding to the second incident angle range, and the projected image light transmittance of the first light-transmitting area is greater than the projected image light transmittance of the second light-transmitting area.

2. The optical element according to claim 1, characterized in that The first incident angle range includes a plurality of first sub-incident angle ranges, each of which corresponds to a first sub-light-transmitting area in the first light-transmitting area; wherein different first sub-light-transmitting areas corresponding to different first sub-incident angle ranges have different projected image light transmittances; The second incident angle range includes multiple second sub-incident angle ranges, each of which corresponds to a second sub-light-transmitting area in the second light-transmitting area; wherein different second sub-light-transmitting areas corresponding to different second sub-incident angle ranges have different projection image light transmittances.

3. The optical element according to claim 2, characterized in that The first incident angle range is 60° to 80°, and a plurality of the first sub-incident angle ranges are between 60° and 80°; The second incident angle range is 15° to 60°, and a plurality of the second sub-incident angle ranges are between 15° and 60°.

4. The optical element according to claim 2 or 3, characterized in that: Each of the first light-transmitting sub-areas is provided with one of a first combined film layer, a first dielectric layer and a first porous material layer; the first combined film layer, the first dielectric layer and the first porous material layer are respectively used to transmit the projection image light corresponding to the first sub-incident angle range; Each of the second light-transmitting sub-areas is provided with one of a second combined film layer, a second dielectric layer and a second porous material layer; the second combined film layer, the second dielectric layer and the second porous material layer are respectively used to transmit the projection image light corresponding to the second sub-incident angle range.

5. The optical element according to claim 4, characterized in that The total number of film layers in the first combined film layer is different from the total number of film layers in the second combined film layer; and / or, The thickness of at least one antireflection film in the first combination of film layers is different from the thickness of at least one antireflection film in the second combination of film layers; and / or, The refractive index of at least one layer of the anti-reflection film in the first combined film layer is different from the refractive index of multiple layers of the anti-reflection film in the second combined film layer.

6. The optical element according to claim 1, characterized in that The first light-transmitting area and the second light-transmitting area are spliced ​​to form a light-receiving surface of the optical element, and a splicing line between the first light-transmitting area and the second light-transmitting area is a straight line or an arc.

7. A transparent display screen, characterized in that: It comprises a screen body, wherein the screen body is composed of the optical element according to any one of claims 1 to 6.

8. A vehicle-mounted display system, comprising a projector and a screen, characterized in that: The screen is the transparent display screen described in right 7.

9. The vehicle-mounted display system according to claim 8, characterized in that: The screen is a vehicle window glass or a windshield.

10. A head-up display system, comprising an image display unit, wherein the image display unit comprises a projector and a reflective element, wherein: The reflective element includes a light receiving surface facing the projection direction of the projector and a reflective surface opposite to the light receiving surface, the reflective surface is formed with a reflective layer, and the light receiving surface is formed with an optical element as described in any one of claims 1 to 6, the projection image light projected by the projector is irradiated to the reflective element, transmitted from the light receiving surface of the reflective element to the reflective surface, and reflected to the display medium via the reflective surface.

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