Optical module for head-up display and optical system for head-up display, vehicle

Abstract

A head-up display optical module and a head-up display optical system for a vehicle, which belong to the technical field of head-up displays, include an image generating element (102) and a shading assembly arranged in sequence, the image generating element (102) configured to generate an image signal, the image signal passing through the shading assembly to enter a receiving end (108), the shading assembly further configured to transmit a portion of external light according to at least one of polarization direction and wavelength, when the image signal passes through the shading assembly, the shading assembly has no or little effect on the image signal. External light passes through the light blocking assembly and the image generating element (102) in order. After the external light passes through the image generating element (102), no image is generated, but the heat from the external light is concentrated on the image generating element (102), causing the temperature of the image generating element (102) to rise. The light blocking assembly is used to block most of the external light and allow a small amount of external light to pass through, thereby reducing the heat from the external light on the image generating element (102), lowering the temperature of the image generating element (102), and ensuring the quality of the image.

Description

[Technical field]

[0001] The present application relates to the technical field of head-up displays, and in particular to an optical module for a head-up display, an optical system for a head-up display, and a vehicle.

[0002] CROSS REFERENCE TO RELATED APPLICATIONS This application claims priority based on a Chinese application filed with the State Intellectual Property Office of the People's Republic of China on March 4, 2021, bearing application number 202110239212.5 and entitled "Optical module for head-up display and optical system for head-up display, vehicle," the entire contents of which are incorporated herein by reference. [Background technology]

[0003] With the development of technology, head-up display technology (HUD) is widely used in the automotive field, and in recent years, augmented reality head-up display (AR HUD) has also been applied to some luxury cars. AR HUD has a wider field of view, a longer virtual image distance, and can blend the displayed image with real objects, which makes it more appealing to users.

[0004] However, because the area of ​​the AR HUD optical element is relatively large, the energy of the external sunlight entering the optical system is more, and the virtual image distance is relatively long, so the position of the image generating unit is closer to the focus of the optical imaging system than that of a general HUD. Therefore, when the sunlight is overflowing, the solar energy is more concentrated on the image generating unit, and accordingly, the temperature of the illuminated area of ​​the image generating unit is very high at this time. If not addressed, the temperature may reach 300°C in extreme cases, which is too much above the general operating temperature of the image generating unit (generally 105°C), affecting the quality of imaging, and even causing the image generating unit to be damaged due to overheating, affecting the operating performance of the image generating unit. Summary of the Invention

[0005] The present application provides an optical module for a head-up display, an optical system for a head-up display, and a vehicle, which can effectively reduce the temperature of an image generating unit and improve the imaging quality and operation performance.

[0006] Some embodiments of the present application provide an optical module for a head-up display, the optical module comprising: an image generating element and a shading assembly disposed in sequence, the image generating element configured to form an image signal, the image signal passing through the shading assembly to enter a receiving end, the shading assembly further configured to transmit a portion of external light according to at least one of a polarization direction and a wavelength.

[0007] Optionally, the light blocking assembly comprises a polarized dust-proof film.

[0008] The polarizing dustproof film includes a transparent base and a polarizing film provided on the transparent base, and the polarization direction of the polarizing film is the same as the light output direction of the image generating element.

[0009] Optionally, the polarizing film is an absorptive polarizing film or a reflective polarizing film.

[0010] Optionally, the light blocking assembly further comprises a filter element, the filter element being located between the polarizing dust-proof film and the image-producing element and configured to transmit a portion of external light according to the wavelength.

[0011] Optionally, the filter element is configured to block at least infrared light and transmit visible light.

[0012] Optionally, the filter element is further configured to block ultraviolet light.

[0013] Optionally, said image-forming element and said filter element are arranged in adhesive contact.

[0014] Optionally, the filter element and the image generating element are spaced apart and independent of each other in the optical path.

[0015] Optionally, at least one reflective surface is further provided between the polarizing dust-proof film and the filter element, and the at least one reflective surface is configured to reflect a light beam incident on the polarizing dust-proof film to the filter element, or to reflect a light beam incident on the filter element to the polarizing dust-proof film.

[0016] Optionally, the reflective surface is curved.

[0017] Some other embodiments of the present application provide an optical system for a head-up display, the optical system comprising: a backlight module; and an optical module for a head-up display according to some embodiments of the present application, wherein an image generating element of the optical module for a head-up display is located on the light output side of the backlight module.

[0018] Some other embodiments of the present application provide a vehicle, comprising: a vehicle body; and an optical system for a head-up display according to some other embodiments of the present application, the optical system for the head-up display is installed in the vehicle body, and a light-shielding assembly and a receiving end of the optical system for the head-up display are respectively located on both sides of a windshield of the vehicle body.

[0019] The embodiment of the present application provides an optical module for a head-up display, an optical system for a head-up display, and a vehicle. The optical module for a head-up display includes an image generating element and a light blocking assembly, which are sequentially installed. The image generating element is configured to generate an image, and a light beam emitted from a light source passes through the image generating element to be formed as an image light, an image signal is generated, and the image light having image signal information is received by a subsequent receiving end through the light blocking assembly to be formed as an image. When the image light passes through the light blocking assembly, it is not affected by the light blocking assembly or is only slightly affected by the light blocking assembly, so that the original parameters of the image light are kept unchanged. For example, the brightness of the image light does not change after the image light passes through the light blocking assembly. In this process, external light enters the optical module for a head-up display from one side of the receiving end, passes through the light blocking assembly and the image generating element in order, and no image is generated after the external light passes through the image generating element, but the heat of the external light is concentrated on the image generating element, causing the temperature of the image generating element to increase, which affects the operating performance of the image generating element. Therefore, the light blocking assembly is used to block most of the external light and transmit only a small amount of external light, thereby reducing the heat of the external light on the image generating element, lowering the temperature of the image generating element, and ensuring the operation performance of the image generating element. The light blocking assembly has no or only a small effect on the image light and can pass the image light. Meanwhile, the light blocking element selects transmittable light from the external light according to the polarization direction or wavelength of the light, or both the polarization direction and wavelength of the light, and blocks most of the external light and transmits only a small amount of external light using the light blocking assembly. In this way, the image light is received by the receiving end and used to generate an image, and the external light is selected by the light blocking assembly, reducing the external light incident on the image generating element, and effectively reducing the heat of light concentrated on the image generating element, thereby achieving the purpose of lowering the surface temperature of the image generating element and ensuring the quality of the image.

[0020] Optionally, the optical system for the head-up display includes a backlight module and the above-mentioned optical module for the head-up display, and the backlight module illuminates the image generating element to form an image light.

[0021] Optionally, a head-up display optical system can be installed to project information such as the vehicle's current speed and navigation information onto an electro-optical display device on the windshield to form an image in front of the windshield. The driver can view navigation information and vehicle speed information by looking directly at the windshield without turning or lowering his / her head, which can improve driving safety. The head-up display optical system can also solve and improve the problem of sunlight overflow, allowing the driver to view a relatively good quality image on the windshield, improving the comfort of the driver's experience. [Brief description of the drawings]

[0022] In order to more clearly describe the technical solutions of the embodiments of the present application, the drawings necessary for the embodiments of the present application are briefly described below. The drawings described are only for illustrating some embodiments of the present application, and are not intended to limit the scope. Those skilled in the art can obtain other related drawings based on these drawings without using inventive abilities. [Figure 1] 1 is a schematic configuration diagram of an optical module for a head-up display according to an embodiment of the present invention. [Diagram 2] 1 is a schematic graph showing the distribution of sunlight. [Diagram 3] 1 is a schematic diagram showing sunlight passing through a polarized dust-proof film. [Figure 4] 1 is a schematic graph showing the distribution of blocked sunlight. [Diagram 5] 2 is a schematic diagram of sunlight passing through a filter element. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] Hereinafter, the technical solutions in the embodiments of the present application will be described clearly and completely with reference to the drawings used in the embodiments of the present application.

[0024] In the description of this application, the directions or positional relationships expressed by terms such as "inside" and "outside" are based on the drawings or are the normal arrangement directions or positional relationships of the products related to this application, and are merely for the purpose of simply and concisely describing this application, and do not necessarily express or imply that the relevant devices or elements have a specific direction, or are configured or operated in a specific direction, and therefore do not limit this application. In addition, terms such as "first" and "second" are merely for the purpose of distinction and description, and do not express or imply relative importance.

[0025] In addition, unless otherwise clearly defined or limited, the terms "installed" and "connected" should be understood in a broad sense. For example, they may be fixedly connected, detachably connected, or integrally connected. They may also be directly connected, indirectly connected via an intermediate object, or the insides of two elements may communicate with each other. Those skilled in the art can understand the specific meanings of the above terms in this application according to the specific circumstances.

[0026] A head-up display, abbreviated as HUD and also called a parallel vision display system, is a multi-function instrument panel that is driver-centered and allows blind operation. It is driver-centered in order to make it easier for the driver to observe the in-vehicle screen and operate the knobs while driving. It allows blind operation in order to prevent the driver from taking their eyes off the road as much as possible. The reason for being able to display navigation information on the multi-function instrument panel is to reduce the driver's distraction from looking at the navigation as much as possible. In other words, it allows the driver to fully concentrate on the road conditions ahead without looking away as much as possible while driving.

[0027] HUDs allow information such as current speed, navigation information, etc. to be projected onto an electro-optical display on the windshield, forming an image in front of the windshield, allowing the driver to see navigation and speed information without having to turn or lower their head.

[0028] In recent years, augmented reality head-up displays (AR HUDs) have begun to be applied to some luxury cars. However, because the area of ​​the AR HUD optical element is relatively large, the energy of the external sunlight entering the optical system is more, and the virtual image distance is relatively long, so the position of the image generating unit is closer to the focus of the optical imaging system than that of a general HUD. Therefore, when the sunlight is flooding, the solar energy is more concentrated on the image generating unit, and at this time, the temperature of the illuminated area of ​​the image generating unit is very high. In order to ensure the imaging quality of the image, it is necessary to reduce the temperature of the illuminated area of ​​the image generating unit.

[0029] CN109219767A proposes a solution to use a cold mirror (flat mirror) instead of a common flat mirror in an imaging system. The proportion of infrared energy in sunlight is relatively high, and the cold mirror only reflects visible light and transmits infrared and ultraviolet light, which can effectively reduce the energy reaching the surface of the image generating unit, and therefore reduce the temperature of the surface.

[0030] However, the multi-layer film of the cold mirror is complicated, and the cost of customization is very high. To meet different needs, cold mirrors are usually manufactured in a relatively large area and cut according to actual needs, so they are generally provided in the form of flat mirrors. However, as users' requirements increase, the traditional combination of free-form surface + flat mirror cannot meet users' requirements for image quality. To meet the needs, generally, both of the two stages of reflectors need to be curved, which greatly limits the application of cold mirror technology.

[0031] The embodiment of the present application provides an optical module for a head-up display that can solve the problem of an image generating unit such as a thin film transistor or a liquid crystal display being unable to operate due to overheating caused by overflowing sunlight during use of a head-up display, particularly an augmented reality head-up display. The optical module for a head-up display according to the embodiment of the present application can prevent a part of sunlight from entering the optical module for a head-up display, and can effectively prevent infrared light and ultraviolet light from reaching the surface of the image generating element 102, thereby reducing the temperature of the surface of the image generating element 102, and can adopt a design in which both of the two stages of reflectors are curved to meet the requirements for imaging quality.

[0032] Specifically, as shown in Fig. 1, some embodiments of the present application provide an optical module for a head-up display, the optical module includes an image generating element 102 and a light blocking assembly that are sequentially arranged. The image generating element 102 is configured to form an image signal, and the image signal is incident on a receiving end through the light blocking assembly. The light blocking assembly is further configured to transmit a part of the external light according to at least one of a polarization direction and a wavelength.

[0033] In the head-up display technology, the image generating element 102 is generally a thin film transistor liquid crystal display (TFT LCD), a light source is located on the light input side of the image generating element 102, the light source and the image generating element 102 are installed correspondingly, the light beam emitted from the light source passes through the image generating element 102 to be formed as image light, an image signal is generated, the image light or the image signal passes through a light blocking assembly and enters the receiving end, and the receiving end forms an image after receiving the image signal.

[0034] When the image signal passes through the shading assembly, the shading assembly has no or very little effect on the image signal, so that the image received by the receiving end is not affected by the shading assembly, and the brightness and quality of the image can be guaranteed.

[0035] When the light blocking assembly uses light blocking by polarization, a light blocking assembly whose polarization direction is the same as the output direction of the image light can be adopted, so that the light blocking assembly does not act on the image light and can transmit the image light.When the light blocking assembly uses light blocking by wavelength, the image light can be transmitted by selecting a light blocking element that can transmit light of the wavelength of the image light.

[0036] The light-blocking assembly can select external light based on the polarization direction or wavelength of the light, or both the polarization direction and wavelength of the light, allowing some of the external light to pass through and blocking other parts.

[0037] Generally, external light enters from one side of the receiving end, passes through the light-shielding assembly, and enters the image-generating element 102. As the external light passes through the image-generating element 102, it does not act on the image-generating element 102 and the image-generating element 102 does not generate an image signal. However, the heat from the external light is concentrated in the image-generating element 102, causing the temperature of the image-generating element 102 to increase, which affects the operating performance of the image-generating element 102.

[0038] When the optical module for head-up display is applied to head-up display technology, it is generally used in a means of transportation such as a car, and when the car is running, it is relatively affected by ambient light, where the external light is sunlight, and when the car is running, it is inevitable that sunlight will be incident on the optical module for head-up display from one side of the receiving end.

[0039] Therefore, it is necessary to use a light blocking assembly to block this portion of external light from entering the image generating element 102 by filtering or reflecting, etc., and to select the external light by the light blocking assembly. In this way, after the external light is selected by the light blocking assembly, most of it is blocked by the light blocking assembly, and only a small amount of external light that is not blocked reaches the image generating element 102, so that the heat of light concentrated on the image generating element 102 is reduced, and the impact of the external light on the image generating element 102 can be reduced or eliminated, solving the problem of sunlight overflow in the prior art, suppressing the rise in temperature of the image generating element 102, and ensuring the stable operation of the image generating element 102.

[0040] As can be seen from the above, two types of light are incident on the optical module for a head-up display: light from a light source that can cause the image generating element 102 to generate an image signal, and external light that is not involved in the generation of an image signal by the image generating element 102. The light from the light source and the external light are incident from two directions, respectively, that is, the light paths that the light from the light source and the external light take through the optical module for a head-up display are opposite to each other.

[0041] An optical module for a head-up display according to some embodiments of the present application includes an image generating element 102 and a shading assembly, which are sequentially arranged. The image generating element 102 is configured to generate an image, and a light beam emitted from a light source passes through the image generating element 102 to be formed as an image light, an image signal is generated, and the image light carrying image signal information is received by a subsequent receiving end through the shading assembly to be formed as an image. When the image light passes through the shading assembly, it is not affected or is only slightly affected by the shading assembly, so that the original parameters of the image light are kept unchanged. For example, the brightness of the image light does not change after the image light passes through the shading assembly. In this process, external light enters the optical module for head-up display from one side of the receiving end, and passes through the light blocking assembly and the image generating element 102 in order. After the external light passes through the image generating element 102, no image is generated, but the heat of the external light is concentrated on the image generating element 102, causing the temperature of the image generating element 102 to increase, which affects the operation performance of the image generating element 102. Therefore, the light blocking assembly is used to block most of the external light and transmit only a small amount of the external light, thereby reducing the heat of the external light at the image generating element 102, lowering the temperature of the image generating element 102, and ensuring the operation performance of the image generating element 102. The light blocking assembly has no or only a small effect on the image light and can transmit the image light. Meanwhile, the light blocking element selects transmittable light from the external light according to the polarization direction or wavelength of the light, or both the polarization direction and wavelength of the light, and uses the light blocking assembly to block most of the external light and transmit only a small amount of the external light. In this way, the image light is received by the receiving end and used to generate an image, and the external light is selected by the shading assembly, the external light incident on the image-generating element 102 is reduced, and the light heat concentrated on the image-generating element 102 is effectively reduced, so as to achieve the purpose of reducing the surface temperature of the image-generating element 102 and ensure the quality of the image.

[0042] When the light blocking element selects external light according to the polarization direction, the light blocking assembly includes a polarized dustproof film 106. As shown in Fig. 3, the polarized dustproof film 106 includes a transparent base 1061 and a polarizing film 1062 provided on the transparent base 1061, and the polarization direction of the polarizing film 1062 is the same as the output direction of the light beam of the image signal formed by the image generating element 102.

[0043] The polarization direction of the polarizing film 1062 and the output direction of the image light formed by the image generating element 102 are the same, which means that the polarization directions of the two are the same, and therefore the image light can pass through the polarizing film 1062 and reach the receiving end.

[0044] External light is scattered and has various polarization directions. Of the external light, that whose polarization direction is the same as the polarization direction of the polarizing film 1062 can pass through the polarizing film 1062, while that whose polarization direction is different from the polarization direction of the polarizing film 1062 cannot pass through the polarizing film 1062 and is blocked by the polarizing film.

[0045] Therefore, when selecting the parameters of the polarizing film 1062, it is necessary to select a polarizing film 1062 that can transmit the image light while blocking most of the external light, and that has the same polarization direction as the image light and can block as much of the external light as possible, so as to achieve the purpose of lowering the temperature of the image generating element 102.

[0046] By selection, the polarized dustproof film 106 can block about half of the external light from entering the optical module for the head-up display, and has no or very little effect on the brightness of the image light formed by the image generating element 102.

[0047] The polarizing dustproof film 106 includes a transparent base 1061 and a polarizing film 1062, and the transparent base 1061 can be made of PC polycarbonate. The polarizing film 1062 is attached to the transparent base 1061, and the polarization direction of the polarizing film 1062 matches the output direction of the image light formed by the image generating element 102.

[0048] The polarizing film 1062 may be an absorptive polarizing film 1062 that absorbs incident light only from a prescribed polarization direction, or it may be a reflective polarizing film 1062 that reflects incident light from a prescribed polarization direction.

[0049] 3, most of the image light emitted from the image generating element 102 can pass through the polarizing film 1062, so there is no effect on the brightness. Only a portion (about 50%) of the external light (sunshine) that is in the same direction as the light emitted from the image generating element 102 can enter the image generating element 102 through the polarizing dustproof film 106, and the remaining portion is blocked by the polarizing dustproof film 106 through absorption or reflection and cannot enter the image generating element 102. Therefore, the solar energy entering the image generating element 102 is effectively reduced, and the purpose of lowering the surface temperature of the image generating element 102 can be achieved.

[0050] Optionally, the light blocking assembly further comprises a filter element 103, which is positioned between the polarizing dust-proof film 106 and the image generating element 102 and is configured to transmit a portion of the external light depending on the wavelength and to block a portion of the light beam of the external light incident through the polarizing dust-proof film 106.

[0051] External light is incident on the filter element 103 from the receiving end through the polarized dustproof film 106. As shown in Fig. 2, the external light is generally sunlight, which has a relatively wide spectrum band and includes infrared light and ultraviolet light in addition to visible light. These rays, especially infrared light, contain a large amount of energy of sunlight. If the rays concentrated on the image-generating element 102 are not dealt with, the temperature of the image-generating element 102 will become very high, which will affect the performance of the image-generating element 102.

[0052] Since infrared light comprises most of the energy of sunlight, the filter element 103 is configured to block at least infrared light, or to block a portion of the infrared light, thereby blocking most of the energy in external light reaching the image generating element 102.

[0053] The filter element 103 is configured to block at least infrared light and transmit visible light. The filter element may be further configured to block ultraviolet light. The filter element 103 is plated with an optical film that allows the filter element 103 to block both ultraviolet light and infrared light, or to block only infrared light or only a portion of infrared light.

[0054] As an example, the filter element 103 blocks ultraviolet light with a wavelength of less than 400 nm and blocks infrared light with a wavelength of more than 680 nm. The energy of the blocked infrared light and ultraviolet light accounts for about 68% of the solar energy entering the optical module for a head-up display.

[0055] The filter element 103 can reflect infrared light (IR) and ultraviolet light (UV) in sunlight and transmit visible light. As shown in FIG. 4 and FIG. 5, the filter element 103 is a filter sheet, and the filter sheet is attached to the image generating element 102. The filter element 103 has a very high transmittance in the visible light range, so it has little effect on the image light emitted from the image generating element 102, that is, it has little effect on the brightness of the image light. In addition, when the filter element 103 reflects infrared light and ultraviolet light, and the sunlight passing through the polarized dustproof film 106 overflows to the surface of the filter element 103, the infrared light and ultraviolet light are reflected and the visible light can be transmitted, and the infrared light has a relatively large energy and cannot reach the surface of the image generating element 102 because it is reflected. Therefore, the temperature of the surface of the image generating element 102 using the filter element 103 is further reduced, and the stability of the operation of the image generating element 102 is improved.

[0056] Optionally, the filter element 103 includes a substrate and a plating film disposed on the substrate, where the substrate of the filter element 103 can be glass D263T, and the plating material of the filter element 103 can be TiO2, SiO2, etc., to improve the blocking effect.

[0057] The filter element 103 and the image generating element 102 may be arranged so as to be adhered to each other, or the filter element 103 and the image generating element 102 may be arranged in the optical path so as to be spaced apart and independent from each other.

[0058] As can be seen from the above, the polarized dustproof film 106 reduces the total amount of external light incident on the filter element 103 by blocking a portion of the external light according to the polarization direction, and the filter element 103 can block at least infrared light according to the wavelength, thereby reducing heat caused by infrared light in the image generating element 102. By combining the polarized dustproof film 106 with the filter element 103 that blocks infrared light and ultraviolet light, the solar energy reaching the surface of the image generating element 102 can be reduced by about 84% by using the optical module for a head-up display according to the embodiment of the present application, compared to a head-up display system that does not have any countermeasures. Here, 84%≒1-50%*32%, where 50% is the transmittance of the polarized dustproof film 106, the polarized dustproof film 106 can reduce the intrusion of external light by 50%, and 32% is the ratio of visible light energy (400nm to 640nm) to the total amount of solar energy, therefore, most of the light energy reaching the surface of the image-generating element 102 is reduced, and the temperature of the surface of the image-generating element 102 is effectively reduced, so that the image-generating element 102 can be effectively protected and the problem of sunlight overflow in head-up display technology can be improved.

[0059] Optionally, at least one reflective surface is further provided between the polarizing dust-proof film 106 and the filter element 103, and the at least one reflective surface is configured to reflect a light beam incident on the polarizing dust-proof film 106 to the filter element 103, or to reflect a light beam incident on the filter element 103 to the polarizing dust-proof film.

[0060] The image light formed by the image generating element 102 passes through the filter element 103 and enters at least one reflecting surface, and is reflected by the at least one reflecting surface to the polarized dust-proof film 106. The external light incident from the receiving end passes through the polarized dust-proof film 106 and enters at least one reflecting surface, and after being reflected by the at least one reflecting surface, enters the filter element 103 and the image generating element 102 in order.

[0061] The reflective surface realizes reflection of the light beam between the filter element 103 and the polarizing dust-proof film 106, and is used for imaging. Exemplarily, two reflecting mirrors, a first reflecting mirror 104 and a second reflecting mirror 105, are used in the embodiment of the present application, and the first reflecting mirror 104 and the second reflecting mirror 105 realize reflection of the light beam between the filter element 103 and the polarizing dust-proof film 106.

[0062] When the reflective surfaces are curved and first reflecting mirror 104 and second reflecting mirror 105 are used, first reflecting mirror 104 has two reflective surfaces, each of which can reflect light from two directions, that is, image light and external light, and both of the two reflective surfaces of first reflecting mirror 104 may be curved, or only one of them may be curved, and the same is true for second reflecting mirror 105.

[0063] In contrast to the problem of the difficulty in processing the curved cold mirror in the prior art, the optical module for head-up displays according to the embodiment of the present application improves and solves the problem of sunlight overflowing by using the polarized dustproof film 106 and the filter element 103. The polarized dustproof film 106 can block about half of the external light from entering the optical module for head-up displays without affecting the image light. The filter element 103 can reflect the infrared light and ultraviolet light that reach the surface of the image generating element 102 when sunlight overflows without affecting the image light. The advantage is that both of the two reflecting mirrors used for imaging of the optical module for head-up displays can be curved, and in this way, the quality of the image formation can be optimized to a relatively good state during imaging, and the optical module for head-up displays can obtain a relatively good image quality. This advantage is particularly prominent in AR HUDs because AR HUDs require a longer virtual image distance and a larger viewing angle.

[0064] Some other embodiments of the present application further provide an optical system for a head-up display, which includes a backlight module 101 and an optical module for a head-up display according to some embodiments of the present application, and an image generating element 102 of the optical module for a head-up display is located on the light output side of the backlight module 101, that is, the light output from the backlight module 101 is formed as image light through the image generating element 102, and an image signal is generated.

[0065] The optical system for head-up displays has a similar structure to the optical module for head-up displays according to the above embodiment, and can achieve the same beneficial effects. The structure and beneficial effects of the optical module for head-up displays have been described in detail in the above embodiment, so a description thereof will be omitted here.

[0066] The above-mentioned optical system for head-up display is applied to a vehicle, and some other embodiments of the present application further provide a vehicle, which includes a vehicle body and the optical system for head-up display according to some other embodiments of the present application, the optical system for head-up display is installed in the vehicle body, and a light-shielding assembly and a receiving end of the optical system for head-up display are respectively located on both sides of the windshield 107 of the vehicle body.

[0067] The optical system for head-up display is installed on the vehicle body, and the light shielding assembly and the receiving end are respectively located on both sides of the windshield 107 of the vehicle body. The imaging principle is that the image generating element 102 reads the display information such as the current speed of the vehicle and navigation information, the backlight module 101 generates uniform light to illuminate the image generating element 102 to form image light, and the image light is then projected onto the windshield 107 through the filter element 103, the first reflecting mirror 104, the second reflecting mirror 105 and the polarizing dustproof film 106, and is reflected by the windshield 107 to enter the driver's visual range (iris 108), where the iris 108 is the receiving end. The above elements form an imaging system, and the image light passes through the imaging system to form a virtual image magnified at a certain distance, and the driver's eyes can see the virtual image if they are within the range of the iris 108.

[0068] The windshield 107 can function as a receiving end, and the windshield 107 is used for imaging. For image light, the windshield 107 reflects a part of the image light and transmits another part. For external light from the outside, the windshield 107 reflects a part of the external light and transmits a part of the external light. Sunlight at a certain angle passes through the windshield 107 and enters the optical system for the head-up display, and is reflected by the optical element and concentrated on the image generating element 102, that is, the phenomenon of sunlight overflow occurs. The shading assembly solves or improves the problem of sunlight overflow, improving the quality of imaging.

[0069] In the vehicle according to the embodiment of the present application, by installing an optical system for head-up display, information such as the vehicle's current speed and navigation information can be projected onto an electro-optical display device on the windshield 107 by the optical system for head-up display, and an image can be formed in front of the windshield 107. The driver can view navigation information and vehicle speed information by looking directly at the windshield 107 without turning or lowering his / her head, thereby improving driving safety. In addition, the optical system for head-up display solves and improves the problem of sunlight overflow, so that the driver can view a relatively good quality image on the windshield 107, improving the comfort of the driver's experience.

[0070] The above is merely an embodiment of the present application, and does not limit the scope of protection of the present application. Those skilled in the art may have various modifications and variations in the present application. As long as it does not deviate from the spirit and principle of the present application, any modifications, equivalent replacements, improvements, etc., will fall within the scope of protection of the present application.

[0071] Industrial Applicability

[0072] The present application provides an optical module for a head-up display, an optical system for a head-up display, and a vehicle. The optical module for a head-up display includes an image generating element and a light blocking assembly, which are sequentially arranged. The image generating element is configured to form an image signal, and the image signal is incident on a receiving end through the light blocking assembly. The light blocking assembly is further configured to transmit a part of the external light according to at least one of a polarization direction and a wavelength. When the image signal passes through the light blocking assembly, the light blocking assembly has no or very little effect on the image signal. When the external light passes through the light blocking assembly and the image generating element in order, no image is generated when the external light passes through the image generating element, but the heat of the external light is concentrated on the image generating element, and the temperature of the image generating element increases. The light blocking assembly is used to block most of the external light and transmit only a small amount of external light, thereby reducing the heat of the external light at the image generating element, lowering the temperature of the image generating element, and ensuring the quality of the image.

[0073] The optical module for a head-up display, the optical system for a head-up display, and the vehicle according to the present application are feasible and can be applied to various industrial applications. For example, the optical module for a head-up display, the optical system for a head-up display, and the vehicle according to the present application can be applied to the technical field of head-up displays. [Explanation of symbols]

[0074] 101 Backlight module 102 Image generating element 103 Filter element 104 1st reflector 105 Second reflector 106 Polarized dust-proof film 1061 Transparent base 1062 Polarizing film 107 Windshield 108 Iris

Claims

1. a sequentially disposed image generating element and a light blocking assembly, the image generating element configured to generate an image signal, the image signal passing through the light blocking assembly to enter a receiving end, the light blocking assembly further configured to transmit a portion of external light according to at least one of a polarization direction and a wavelength; the light-blocking assembly includes a polarized dust-proof film; The polarizing dust-proof film includes a transparent base and a polarizing film provided on the transparent base, the polarization direction of the polarizing film being the same as the light output direction of the image generating element, The light blocking assembly further includes a filter element, the filter element being located between the polarizing dust-proof film and the image generating element and configured to transmit a portion of the external light according to the wavelength; the filter element and the image generating element are disposed in an optical path so as to be spaced apart and independent from each other; A first reflecting mirror and a second reflecting mirror are further provided between the polarizing dust-proof film and the filter element, and the first reflecting mirror and the second reflecting mirror are configured to reflect a light beam incident on the polarizing dust-proof film to the filter element, and to reflect a light beam incident on the filter element to the polarizing dust-proof film, and the first reflecting mirror and the second reflecting mirror each have two reflecting surfaces, which respectively reflect light from two directions, i.e., image light and external light, and both of the reflecting surfaces are curved surfaces.

1. An optical module for a head-up display.

2. The polarizing film is an absorptive polarizing film or a reflective polarizing film.

2. The optical module for a head-up display according to claim 1.

3. The filter element is configured to block at least infrared light and transmit visible light.

2. The optical module for a head-up display according to claim 1.

4. The filter element is further configured to block ultraviolet light.

4. The optical module for a head-up display according to claim 3.

5. A head-up display optical module according to any one of claims 1 to 4, wherein an image generating element of the head-up display optical module is located on the light output side of the backlight module. An optical system for a head-up display.

6. A vehicle body and the optical system for a head-up display according to claim 5, wherein the optical system for a head-up display is installed on the vehicle body. A vehicle characterized by:

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