Optical system, projection display device, and transport vehicle

Abstract

The present application relates to an optical system, a projection display device, and a transport vehicle. The optical system is applied to a projection display device having an image source module. The optical system comprises a beam splitting module and a beam expanding module, and the beam splitting module comprises a first beam splitting unit and a second beam splitting unit which are arranged in parallel; after being expanded by the beam expanding module, an image source light beam is reflected to the first beam splitting unit; the first beam splitting unit transmits part of the image source light beam so as to form a first virtual image, and reflects part of the image source light beam to form a first reflected light beam, and the first reflected light beam can be conducted to the second beam splitting unit; and the second beam splitting unit reflects the first reflected light beam so as to form a second virtual image, and the imaging distances of the first virtual image and the second virtual image are different. The optical system in embodiments can form at least two virtual images having different imaging distances at the same time, so that the at least two virtual images can be presented using a relatively simple structure, and the presented image has a relatively rich level of detail.

Description

Optical system, projection display device and transport vehicle

[0001] Cross-reference to Related Applications

[0002] This application claims priority to Chinese applications with application numbers 2024104091605, 2024206955496, filed on April 7, 2024, the contents of which are hereby incorporated by reference in their entirety for all purposes. TECHNICAL FIELD

[0003] The present application relates to the technical field of projection display systems, and in particular to an optical system, a projection display device and a transport vehicle. BACKGROUND

[0004] With the progress of science and technology, more and more vehicles are integrated with head-up display systems. The head-up display system can project the vehicle speed, engine speed, navigation and other information to the front windshield, so that the driver can obtain key information of the vehicle without looking away from the driving front, thereby improving driving safety.

[0005] However, the current head-up display system includes an image source and a reflecting member. The image source is used to emit an image light beam, and the reflecting member is used to reflect the image light beam to the windshield to form an image virtual image for the driver to view. Since the traditional reflecting member has a single effect on the light beam, it forms an image virtual image with a fixed imaging distance after reflection. The content of the virtual image is relatively flat, and the display effect is relatively single. SUMMARY

[0006] The present application provides an optical system, a projection display device and a transport vehicle.

[0007] In a first aspect, the present application provides an optical system. The optical system is applied to a projection display device having an image source module. The image source module is used to emit an image source light beam. The optical system includes a light splitting module and a beam expanding module. The light splitting module includes a first light splitting unit and a second light splitting unit arranged side by side. The beam expanding module is adapted to be arranged on the optical path of the image source light beam. After the beam expanding effect of the beam expanding module, the image source light beam is reflected by the beam expanding module to the first light splitting unit. The first light splitting unit is used to transmit part of the image source light beam to form a first projection light beam, and conduct the first projection light beam to a target imaging carrier to form a first virtual image. The first light splitting unit is also used to reflect part of the image source light beam to form a first reflected light beam, and conduct the first reflected light beam to the second light splitting unit. The second light splitting unit is used to reflect at least part of the first reflected light beam to form a second projection light beam, and conduct the second projection light beam to the target imaging carrier to form a second virtual image. The imaging distances of the first virtual image and the second virtual image are different.

[0008] In a second aspect, the present application provides a projection display device, the projection display device comprising an image source module and the optical system as above, the image source module being configured to emit an image source light beam; and the optical system being located on an optical path of the image source light beam.

[0009] In a third aspect, the present application provides a transportation vehicle, the transportation vehicle comprising a vehicle body, a windshield and the projection display device as above. The windshield is mounted on the vehicle body, and the projection display device is configured to project on the windshield to form the first virtual image and the second virtual image.

[0010] The present application provides an optical system, the optical system being applied to a projection display device having an image source module, the image source module being capable of emitting an image source light beam. The optical system comprises a light splitting module and a beam expanding module. The beam expanding module is located on an optical path of the image source light beam, and the beam expanding module has a beam expanding effect and a reflecting effect on the image source light beam. Specifically, the image source light beam is reflected to the light splitting module by the beam expanding module after the beam expanding effect of the beam expanding module. The light splitting module comprises a first light splitting unit and a second light splitting unit arranged side by side. The first light splitting unit is configured to transmit part of the image source light beam to form a first projection light beam, and to conduct the first projection light beam to a target imaging carrier to form a first virtual image. The first light splitting unit is also configured to reflect part of the image source light beam to form a first reflected light beam, and to conduct the first reflected light beam to the second light splitting unit. The second light splitting unit is configured to reflect at least part of the first reflected light beam to form a second projection light beam, and to conduct the second projection light beam to the target imaging carrier to form a second virtual image. The imaging distances of the first virtual image and the second virtual image are different.

[0011] In the optical system provided by the present application, the light splitting module comprises at least the first light splitting unit and the second light splitting unit arranged side by side, so as to form two projection light beams and conduct the two projection light beams to the windshield to form two virtual images. The relative position and distance of the first light splitting unit relative to the windshield are different from the relative position and distance of the second light splitting unit relative to the windshield, so that the imaging distances of the two virtual images are different. Therefore, the image layer is relatively rich, the display effect of information is relatively good, and the structure for realizing the same is relatively simple.

[0012] Further, in the embodiment, the images with rich levels can be used to carry different information, which is beneficial to make the information displayed by the display device more diverse. As an example, the contents of the two virtual images can be set to be the same, such as an indication arrow or a lane line. In the process of real scene fusion, the two virtual images of near and far can cooperate and correspond to a longer road section in the environment, which is helpful for the driver to understand the road conditions and improve the navigation effect. In the embodiment, the contents of the two virtual images can also be set to be different. For example, the imaging content of one virtual image can be the speed, fuel quantity and the like of the transport vehicle, and the imaging content of the other virtual image can be road indication signs, such as a lane line, an indication arrow, a warning sign and the like, so as to provide more road information and transport vehicle information to the driver at the same time, so as to improve the understanding degree of the driver on the transport vehicle and the road conditions. BRIEF DESCRIPTION OF DRAWINGS

[0013] In order to more clearly illustrate the technical solutions of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0014] Fig. 1 is a structural schematic diagram of a transport vehicle provided by the embodiment of the present application.

[0015] Fig. 2 is a structural schematic diagram of a projection display device shown in Fig. 1.

[0016] Fig. 3 is a structural schematic diagram of an optical module of the projection display device shown in Fig. 2.

[0017] Fig. 4 is a structural schematic diagram of a light splitting module of the projection display device shown in Fig. 2.

[0018] Fig. 5 is a structural schematic diagram of the light splitting module of the projection display device shown in Fig. 2, which has a plurality of second light splitting units.

[0019] Fig. 6 is a structural schematic diagram of the optical module of the projection display device shown in Fig. 2, which is provided with a beam folding module.

[0020] 1000, transport vehicle, 900, body, 910, cockpit, 800, windshield, 810, projection imaging surface, 100, projection display device, 20, image source module, 10, optical system, 110, light splitting module, 1110, first light splitting unit, 1111, first light-transmissive main body, 1112, first light-receiving surface, 1113, first optical film layer, 1114, first projection light beam, 1115, first virtual image, 1116, first reflected light beam, 1117, first incident surface, 1120, second light splitting unit, 1121, first light-transmissive main body, 1122, first light-receiving surface, 1123, second optical film layer, 1124, second projection light beam, 1125, second virtual image, 1126, second incident surface, 120, beam expanding module, 130, beam folding module. DETAILED DESCRIPTION

[0021] In order to make persons skilled in the art better understand the scheme of the present application, the technical scheme in the embodiments of the present application will be clearly and completely described below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by persons skilled in the art without creative work shall fall within the scope of protection of the present application.

[0022] Please refer to FIG. 1, the present application provides an optical system 10, a projection display device 100 provided with the optical system 10, and a transport vehicle 1000 configured with the projection display device 100. The transport vehicle 1000 in the present embodiment can be a land vehicle such as a car, a truck or a racing car. The transport vehicle 1000 can include a body 900 and a windshield 800, wherein the body 900 is the main structure of the transport vehicle 1000, and the internal space of the body 900 can be divided into space regions such as a cockpit 910, a passenger cabin and a cargo cabin according to functions, wherein the cockpit 910 is used for accommodating a driver and is located at the front end of the internal space of the body 900 in the advancing direction of the transport vehicle 1000. The body 900 is provided with an observation window in communication with the cockpit 910 at the front side in the advancing direction thereof, and the windshield 800 is embedded in the observation window, so that the driver can observe the road conditions through the observation window.

[0023] Referring to FIG. 1 and FIG. 2, the transport vehicle 1000 in the embodiment can further comprise a projection display device 100, the projection display device 100 is installed in the cockpit 910, the projection display device 100 can cooperate with the windshield 800 to form at least two virtual images, specifically, the windshield 800 serves as a target imaging carrier, and the windshield 800 defines a projection imaging surface 810 on the side facing the cockpit 910, the projection display device 100 can emit at least two light beams, the at least two light beams are conducted to the projection imaging surface 810 on the windshield 800, the windshield 800 reflects the at least two light beams to the human eye, and the human eye can observe at least two virtual images. In the embodiment, the imaging contents of the at least two virtual images can be the same or different. As an example, the imaging contents of the two virtual images are the same, for example, can be road indication signs (such as guide arrows, lane lines, etc.). As another example, the imaging contents of the at least two virtual images can also be different, for example, the imaging content of one virtual image can be the speed of the transport vehicle 1000, the amount of oil, etc., and the imaging content of the other virtual image can be road indication signs, such as lane lines, guide arrows, warning signs, etc.

[0024] Referring to FIG. 2, in the embodiment, the projection display device 100 comprises an image source module 20 and an optical system 10. The image source module 20 is used to emit an image source light beam, and the optical system 10 is located on the light path of the image source light beam. The optical system 10 can perform light splitting processing on the image source light beam to form at least two projection light beams, and the projection light beams can conduct the at least two projection light beams to the windshield 800 and form at least two virtual images. The embodiment does not limit the type of the image source module 20. As an example, the image source module 20 can be an image generator, and the image generator can emit the image source light beam. As another example, the image source module 20 can comprise an image display source and an illuminating lamp (such as a laser lamp or an LED lamp), and the illuminating lamp emits illuminating light to irradiate the image display source to form the image source light beam.

[0025] Please refer to FIG. 2 and FIG. 3, in the embodiment, the optical system 10 comprises a light splitting module 110, the light splitting module 110 is used for light splitting processing of the image source light beam and forming at least two projection light beams. The optical system 10 can also comprise a beam expanding module 120, the beam expanding module 120 is arranged on the light path of the image source light beam. The beam expanding module 120 receives the image source light beam before the light splitting module 110, the beam expanding module 120 is used for expanding the image source light beam to increase the beam area of the image source light beam, and the image source light beam is conducted to the light splitting module 110. Under the arrangement of the embodiment, the beam area of the projection light beam can be avoided to be too small to cause the size of the virtual image formed by the projection light beam after the light splitting processing to be too small, and the power density and irradiance of the image source light beam can be reduced, so as to avoid the beam expanding module 120 and the light splitting module 110 being irradiated by the too strong image source light beam, thereby prolonging the service life of the beam expanding module 120 and the light splitting module 110. The embodiment does not limit the type of the beam expanding module 120, as an example, the beam expanding module 120 can be a concave mirror, which can provide the function of expanding the image source light beam by adjusting the distance between the concave mirror and the light splitting module 110, and the concave mirror can also reflect the image source light beam to the light splitting module 110. As another embodiment, the beam expanding module 120 can be a convex mirror, which can expand the image source light beam and reflect the image source light beam to the light splitting module 110.

[0026] Please refer to FIG. 2 and FIG. 3, the light splitting module 110 in the embodiment at least comprises a first light splitting unit 1110 and a second light splitting unit 1120, the light path of the image source light beam is changed after the beam expanding function of the beam expanding module 120 and is conducted to the first light splitting unit 1110 and the second light splitting unit 1120 in turn and forms two projection light beams. Specifically, the image source light beam is conducted to the first light splitting unit 1110, the first light splitting unit 1110 can transmit part of the image source light beam and form a first projection light beam 1114, the first projection light beam 1114 is conducted to the projection imaging surface 810 of the windshield 800 and forms a first virtual image 1115. The first light splitting unit 1110 can also reflect part of the image source light beam, the part of the image source light beam forms a first reflected light beam 1116 after being reflected by the first light splitting unit 1110, and the first reflected light beam 1116 can be conducted to the second light splitting unit 1120.

[0027] The second light splitting unit 1120 has a reflecting effect on the first reflected light beam 1116, and the first reflected light beam 1116 is reflected by the second light splitting unit 1120 after being transmitted to the second light splitting unit 1120. After the reflection of the first reflected light beam 1116 by the second light splitting unit 1120, the second projection light beam 1124 is formed, and the second projection light beam 1124 is transmitted to the projection imaging surface 810 and forms the second virtual image 1125. It should be understood that the first projection light beam 1114 and the second projection light beam 1124 are part of the light beams in the image source light beam, and the optical path of the second projection light beam 1124 is different from that of the first projection light beam 1114, the imaging distance of the second virtual image 1125 is different from that of the first virtual image 1115, and the imaging distance of the second virtual image 1125 is farther than that of the first virtual image 1115. In other embodiments, more light splitting units can be provided to form more projection light beams with different optical paths and more virtual images with different imaging distances.

[0028] In summary, in the optical system 10 provided in the present application, the light splitting module 110 at least includes the first light splitting unit 1110 and the second light splitting unit 1120 arranged side by side, so as to form two projection light beams and transmit them to the windshield 800 to form two virtual images. The relative position and distance of the first light splitting unit 1110 relative to the windshield 800 are different from those of the second light splitting unit 1120 relative to the windshield 800, so the imaging distances of the two virtual images are different, the image hierarchy is rich, the information display effect is relatively good, and the structure for realizing the same is relatively simple.

[0029] Further, in the present embodiment, the two virtual images with rich hierarchy can be used to carry various different information, which is beneficial to make the information displayed by the display device more diverse. As an example, the contents of the two virtual images can be set to be the same, for example, an indicating arrow or a lane line. In the process of real scene fusion, the two virtual images with different distances can cooperate and correspond to a longer road section in the environment, which is helpful for the driver to understand the road conditions and improve the navigation effect. The contents of the two virtual images in the present embodiment can also be set to be different, for example, the imaging content of one virtual image can be the speed, fuel quantity, etc. of the transport vehicle 1000, and the imaging content of the other virtual image can be road indicating signs such as lane lines, indicating arrows, warning signs, etc., so as to provide more road information and information of the transport vehicle 1000 to the driver at the same time, so as to improve the understanding of the driver on the transport vehicle 1000 and the road conditions.

[0030] Please refer to FIG. 3 and FIG. 4, the embodiment does not limit the type of the first light splitting unit 1110, and the first light splitting unit 1110 can be a diffractive optical element, a polygon mirror, or an optical device such as a polygon prism. In the embodiment, the first light splitting unit 1110 includes a first light receiving surface 1112, and the image source light beam can be conducted to the first light receiving surface 1112 after the turning action of the beam expansion module 120. The first light splitting unit 1110 can also include a first light transmission main body 1111, and the first light receiving surface 1112 is located inside the first light transmission main body 1111. The application does not limit the position of the first light receiving surface 1112 on the first light transmission main body 1111, and can be specifically set according to the type of the first light transmission main body 1111. For example, the first light transmission main body 1111 in the embodiment includes two identical right-angle prisms, and the inclined surfaces of the two right-angle prisms are attached to each other and define the first light receiving surface 1112, so that the first light receiving surface 1112 is located inside the first light transmission main body 1111 in the embodiment. In other embodiments, the first light transmission main body 1111 can be a transparent glass plate, and the first light receiving surface 1112 can be located on the surface of the transparent glass plate. In the embodiment, the first light receiving surface 1112 is provided with a first optical film layer 1113, and the first optical film layer 1113 can be clamped by the two right-angle prisms mentioned above, or can be plated or attached to one inclined surface of one right-angle prism. In the embodiment, the first optical film layer 1113 is used to transmit part of the image source light beam to form a first projection light beam 1114, and is also used to reflect part of the image source light beam to change the optical path of the image source light beam. The reflected image source light beam forms a first reflected light beam 1116, and the first reflected light beam 1116 is conducted towards the second light splitting unit 1120.

[0031] In the embodiment, the reflectivity of the first optical film layer 1113 to the image source light beam ranges from greater than or equal to 25% to less than or equal to 75%. For example, the reflectivity of the first optical film layer 1113 to the image source light beam can be 25%, 30%, 40%, 50%, 60%, 70%, 75%, etc. In some embodiments, the reflectivity range of the first optical film layer 1113 to the image source light beam is related to the incident angle a of the image source light beam on the first optical film layer 1113, and the two are approximately inversely proportional, which will be specifically described below.

[0032] Please refer to FIG. 4, the incidence angle a of the image source light beam on the first optical film layer 1113 can be adjusted according to the actual application requirements, for example, the light splitting module 110 can be taken as a reference to change the position of the image source module 20 or the beam expander module 120, so that the optical path of the image source light beam is changed, and then the incidence angle a of the image source light beam on the first optical film layer 1113 is changed. The range of the incidence angle a of the image source light beam on the first optical film layer 1113 is greater than or equal to 30° and less than or equal to 60°. For example, the incidence angle a of the image source light beam on the first optical film layer 1113 can be 30°, 35°, 40°, 45°, 50°, 55°, 60°, etc. As an example, when the incidence angle a is 30°, the reflectivity of the first optical film layer 1113 to the image source light beam is relatively high (about 75%). As another example, when the incidence angle a is 60°, the reflectivity of the first optical film layer 1113 to the image source light beam is relatively low (about 25%). As another embodiment, when the incidence angle a is 45°, the reflectivity of the first optical film layer 1113 to the image source light beam is about 50%.

[0033] In the embodiment, the first light-transmitting body 1111 has a first incidence surface 1117, which is one of the right-angle surfaces of the right-angle triangular prism. The included angle between the first incidence surface 1117 and the first optical film layer 1113 ranges from greater than or equal to 30° to less than or equal to 60°. For example, the included angle between the first incidence surface 1117 and the first optical film layer 1113 can be 30°, 35°, 40°, 45°, 50°, 55°, 60°, etc. In the embodiment, the image source light beam can be vertically incident on the first incidence surface 1117, which can reduce the reflection of the image source light beam by the first incidence surface 1117 and reduce the light loss of the image source light beam in the transmission process. In the embodiment, when the included angle between the first incidence surface 1117 and the first optical film layer 1113 is 30°, the incidence angle a is 30°; when the included angle between the first incidence surface 1117 and the first optical film layer 1113 is 45°, the incidence angle a is 45°; and when the included angle between the first incidence surface 1117 and the first optical film layer 1113 is 60°, the incidence angle a is 60°.

[0034] Please refer to FIG. 3 and FIG. 4, the embodiment does not limit the type of the second light splitting unit 1120, and the second light splitting unit 1120 can be a diffractive optical element, a polygon mirror, or a polygon prism, or the like. In the embodiment, the second light splitting unit 1120 includes a second light receiving surface 1122, and the first reflected light beam 1116 can be conducted to the second light receiving surface 1122. The second light splitting unit 1120 can also include a second light transmitting body 1121, and the second light receiving surface 1122 is located inside the second light transmitting body 1121. The application does not limit the position of the second light receiving surface 1122 on the second light transmitting body 1121, and can be specifically set according to the type of the second light transmitting body 1121. For example, the second light transmitting body 1121 in the embodiment includes two identical right-angle triangular prisms, the inclined surfaces of the two right-angle triangular prisms are attached to each other and define the second light receiving surface 1122, so that the second light receiving surface 1122 is located inside the second light transmitting body 1121 in the embodiment. In other embodiments, the second light transmitting body 1121 can be a transparent glass plate, and the second light receiving surface 1122 can be located on the surface of the transparent glass plate. In the embodiment, a second optical film layer 1123 is arranged on the second light receiving surface 1122, and the second optical film layer 1123 can be clamped by the two right-angle triangular prisms mentioned above, or can be plated or attached to one inclined surface of one of the right-angle triangular prisms. In the embodiment, the second optical film layer 1123 is used to reflect at least part of the image source light beam to form a second projection light beam 1124.

[0035] Please refer to FIG. 3 and FIG. 4, in the embodiment, the second light transmitting body 1121 and the first light transmitting body 1111 are arranged in parallel (such as bonding, splicing) along the conducting direction of the first reflected light beam 1116, and after the second light transmitting body 1121 and the first light transmitting body 1111 are connected, they are generally in the form of an integrated structure such as a flat lens or a curved lens, so that the structure of the light splitting module 110 is more compact, the light splitting module 110 is easy to install, and the light splitting module 110 occupies less space. As known from the foregoing, in the embodiment, the first light splitting unit 1110 formed by splicing the two right-angle triangular prisms and the second light splitting unit 1120 formed by splicing the two right-angle triangular prisms are connected and attached, so that the first reflected light beam 1116 can be conducted in the prisms, avoiding the first reflected light beam 1116 being conducted in the air, and reducing the loss of light during the conduction of the first reflected light beam 1116.

[0036] In the present embodiment, the reflectivity of the second optical film layer 1123 to the first reflected light beam 1116 ranges from greater than or equal to 25% to less than or equal to 75%. For example, the reflectivity of the second optical film layer 1123 to the image source light beam can be 25%, 30%, 40%, 50%, 60%, 70%, 75%, etc. The reflectivity of the second optical film layer 1123 to the first reflected light beam 1116 is related to the incident angle a of the first reflected light beam on the first optical film layer 1113, and the two are approximately inversely proportional, which will be described in detail below.

[0037] Referring to FIG. 4, in the present embodiment, the incident angle b of the first reflected light beam 1116 on the second optical film layer 1123 ranges from greater than or equal to 30° to less than or equal to 60°. As an example, when the incident angle b is 30°, the reflectivity of the second optical film layer 1123 to the first reflected light beam 1116 is relatively high (approximately 75%). As another example, when the incident angle b is 60°, the reflectivity of the second optical film layer 1123 to the first reflected light beam 1116 is relatively low (approximately 25%). As another example, when the incident angle b is 45°, the reflectivity of the second optical film layer 1123 to the first reflected light beam 1116 is approximately 50%.

[0038] Please refer to FIG. 4, in the embodiment, the second light-transmitting body 1121 has a second incident surface 1126, the first reflected light beam 1116 enters the second light-transmitting body 1121 via the second incident surface 1126. As known from the foregoing, the second incident surface 1126 is a right-angle surface of one of the right-angle triangular prisms included in the second light-transmitting body 1121, and the right-angle surface is attached to the first light-transmitting body 1111. It can be understood that the different shapes of the two right-angle triangular prisms included in the second light-transmitting body 1121 will result in different angles between the second incident surface 1126 and the second optical film layer 1123, and further affect the incident angle β of the first reflected light beam 1116 on the second optical film layer 1123. In the embodiment, the angle between the second incident surface 1126 and the second optical film layer 1123 ranges from greater than or equal to 30° to less than or equal to 60°, and the angle between the second incident surface 1126 and the second optical film layer 1123 can be 30°, 35°, 40°, 45°, 50°, 55°, 60°, etc. In the embodiment, the angle between the first incident surface 1117 and the first optical film layer 1113 can be set to 45°, and the image source light beam is perpendicularly incident on the first incident surface 1117, the first optical film layer 1113 reflects part of the image source light beam to form the first reflected light beam 1116, the first reflected light beam 1116 is perpendicularly emitted from the vertical prism surface adjacent to the first incident surface 1117, and is perpendicularly incident on the second incident surface 1117. In the process of conducting the image source light beam from the first light-splitting unit 1110 to the second light-splitting unit 1120, the light loss of the image source light beam in the conducting process is low. In the embodiment, when the angle between the second incident surface 1126 and the second optical film layer 1123 is 30°, the incident angle β is 30°; when the angle between the second incident surface 1126 and the second optical film layer 1123 is 45°, the incident angle β is 45°; and when the angle between the second incident surface 1126 and the second optical film layer 1123 is 60°, the incident angle β is 60°.

[0039] The embodiment does not limit the types of the first optical film layer 1113 and the second optical film layer 1123, and the first optical film layer 1113 and the second optical film layer 1123 can be selected according to the actual projection requirements and the structures of the components in the optical system 10, and cooperate with each other to achieve the purpose of forming multiple virtual images. The present application provides multiple embodiments, which will be introduced one by one below.

[0040] Referring to FIG. 3 and FIG. 4, in the first embodiment, the light splitting module 110 comprises a first light splitting unit 1110 and a second light splitting unit 1120. The first optical film layer 1113 is a semi-transparent and semi-reflective film, and the second optical film layer 1123 is a full-reflective film. After the image source light beam is transmitted to the first optical film layer 1113, the first optical film layer 1113 transmits part of the image source light beam to form a first projection light beam 1114, and reflects part of the image source light beam to change the optical path of the image source light beam. The reflected image source light beam forms a first reflected light beam 1116 and is transmitted to the second optical film layer 1123. The second optical film layer 1123 can reflect as much as possible the first reflected light beam 1116 and form a second projection light beam 1124. In the first embodiment, the light splitting module 110 can form two projection light beams, and the two virtual images formed by the two projection light beams have the same content. The second optical film layer 1123 is a full-reflective film, which can ensure that the light intensity of the second projection light beam 1124 is close to the light intensity of the first projection light beam 1114, so as to make the brightness of the first virtual image 1115 and the second virtual image 1125 close to each other, which is convenient for the driver to observe. In the first embodiment, the first light splitting unit 1110 can be provided in plurality. After the image source light beam is transmitted to the first optical film layer 1113 of the first light splitting unit 1110, the first optical film layer 1113 transmits part of the image source light beam and reflects part of the image source light beam to form a first reflected light beam 1116. The plurality of first light splitting units 1110 are arranged in sequence along the optical path of the first reflected light beam 1116. The second light splitting unit 1120 is connected with the last first light splitting unit 1110 on the optical path of the first reflected light beam 1116.

[0041] Referring to FIG. 5, in the second embodiment, the light splitting module 110 includes a first light splitting unit 1110 and a plurality of second light splitting units 1120, which are arranged in sequence along the light path of the first reflected light beam 1116 and are connected to one side of the first light splitting unit 1110. In the second embodiment, the first optical film layer 1113 is a semi-transparent and semi-reflective film, and the second optical film layer 1123 of each second light splitting unit 1120 is also a semi-transparent and semi-reflective film. After the image source light beam is transmitted to the first optical film layer 1113, the first optical film layer 1113 transmits part of the image source light beam to form the first projection light beam 1114, and reflects part of the image source light beam to change the light path of the image source light beam. The reflected image source light beam forms the first reflected light beam 1116. The first reflected light beam 1116 can be sequentially transmitted to each second optical film layer 1123. Specifically, the first reflected light beam 1116 is first transmitted to the second optical film layer 1123 of the second light splitting unit 1120 connected directly to the first light splitting unit 1110. The second optical film layer 1123 reflects part of the first reflected light beam 1116 to the windshield 800 to form the second virtual image 1125 and transmits part of the first reflected light beam 1116 to the second optical film layer 1123 of the next second light splitting unit 1120. In this way, the first reflected light beam 1116 is sequentially transmitted to each second light splitting unit 1120 to form a plurality of second virtual images 1125, wherein the imaging distances of the plurality of second virtual images 1125 are different, and the plurality of second virtual images 1125 are arranged in sequence from near to far.

[0042] In the second embodiment, a plurality of second light splitting units 1120 are provided, and each second light splitting unit 1120 is provided with a semi-transparent and semi-reflective film. The plurality of second light splitting units 1120 can form a plurality of second virtual images 1125 with different imaging distances and the same content. Each second virtual image 1125 is different from the first virtual image 1115 in terms of the content and the imaging distance. The plurality of second virtual images 1125 and the first virtual image 1115 can correspond to a longer road section in the environment, further improving the navigation effect. In the second embodiment, the second light splitting unit 1120 farthest from the first light splitting unit 1110 can be provided with a full reflection film, so that the second virtual image 1125 formed by the second light splitting unit 1120 has sufficient brightness, so that the driver can recognize the content of each second virtual image 1125.

[0043] Referring to FIG. 4, in the third embodiment, the light splitting module 110 includes a first light splitting unit 1110 and a second light splitting unit 1120. The first optical film layer 1113 is a polarized film, and the second optical film layer 1123 is a total reflection film. After the image source light beam is transmitted to the first optical film layer 1113, the polarized film transmits the light of the first polarization state in the image source light beam and forms a first projection light beam 1114, which is transmitted to the windshield 800 and forms a first virtual image 1115. The polarized film reflects the light of the second polarization state in the image source light beam to form a first reflected light beam 1116, wherein the first polarization state and the second polarization state are different. The first reflected light beam 1116 can be transmitted to the second optical film layer 1123, and the second optical film layer 1123 can reflect as many first reflected light beams 1116 as possible and form a second projection light beam 1124. In the third embodiment, by arranging the polarized film, the flexibility of the composition of the multiple virtual images in the optical system 10 can be improved, the contents of the two virtual images formed by the two projection light beams can be set to be the same to correspond to a longer section in the environment, or can be set to be different to provide more information to the driver to help the driver understand the vehicle condition and the road condition. And the second optical film layer 1123 is a total reflection film, which can ensure the light intensity of the second projection light beam 1124, and facilitate the driver to observe.

[0044] Referring to FIG. 5, in the fourth embodiment, the light splitting module 110 includes the first light splitting unit 1110 and a plurality of second light splitting units 1120, the plurality of second light splitting units 1120 are arranged and connected on one side of the first light splitting unit 1110 along the light path of the first reflected light beam 1116. In the second embodiment, the first optical film layer 1113 is a polarized film, and the second optical film layer 1123 of each second light splitting unit 1120 is a semi-transmissive and semi-reflective film. After the image source light beam transmits to the first optical film layer 1113, the first optical film layer 1113 transmits the light rays of the first polarization state in the image source light beam to form the first projection light beam 1114, and reflects the light rays of the second polarization state in the image source light beam to change the light path of the light rays of the second polarization state, and the reflected light rays of the second polarization state form the first reflected light beam 1116, wherein the first polarization state and the second polarization state are different. The first reflected light beam 1116 can be sequentially transmitted to each second optical film layer 1123. Specifically, the first reflected light beam 1116 is first transmitted to the second optical film layer 1123 of the second light splitting unit 1120 directly connected to the first light splitting unit 1110, the second optical film layer 1123 reflects part of the first reflected light beam 1116 to the windshield 800 to form the second virtual image 1125 and transmits part of the first reflected light beam 1116 to the second optical film layer 1123 of the next second light splitting unit 1120, and so on, so that the first reflected light beam 1116 is sequentially transmitted to each second light splitting unit 1120 to form a plurality of second virtual images 1125 with the same content, wherein the imaging distances of the plurality of second virtual images 1125 are different, and the plurality of second virtual images 1125 are arranged and disposed in sequence from near to far.

[0045] In the fourth embodiment, a plurality of second light splitting units 1120 are provided, and each second light splitting unit 1120 is provided with a semi-transmissive and semi-reflective film, the plurality of second light splitting units 1120 can form a plurality of second virtual images 1125 with different imaging distances and the same content, and the imaging distance of the first virtual image 1115 is different from that of the plurality of second virtual images 1125. In this embodiment, the polarized film can improve the flexibility of the composition of the plurality of virtual images in the optical system 10, the content of the first virtual image 1115 and the plurality of second virtual images 1125 can be the same to correspond to a longer road section in the environment, further improving the navigation effect; the content of the first virtual image 1115 and the plurality of second virtual images 1125 can be different, for example, the content of the first virtual image 1115 includes information (fuel level, power level, speed, etc.) of the transport vehicle 1000, and the content of the second virtual image 1125 includes instruction signs (lane lines, indication arrows, etc.), to improve the understanding of the transport vehicle 1000 and the road conditions by the driver. In the fourth embodiment, the second light splitting unit 1120 farthest from the first light splitting unit 1110 can be provided with a full reflection film, so that the second virtual image 1125 formed by the second light splitting unit 1120 has sufficient brightness, so that the driver can recognize the content of each second virtual image 1125.

[0046] Referring to FIG. 4, in the fifth embodiment, the light splitting module 110 includes a first light splitting unit 1110 and a second light splitting unit 1120. The first optical film layer 1113 is a polarized film, and the second optical film layer 1123 is also a polarized film. Specifically, after the image source light beam is transmitted to the first optical film layer 1113, the first optical film layer 1113 transmits light rays of a first polarization state in the image source light beam to form a first projection light beam 1114, and reflects light rays of a second polarization state in the image source light beam to change the optical path of the light rays of the second polarization state. The reflected light rays of the second polarization state form a first reflected light beam 1116, wherein the first polarization state and the second polarization state are different. The first reflected light beam 1116 can be transmitted to the second optical film layer 1123, and the second optical film layer 1123 can reflect the light rays of the second polarization state to form a second projection light beam 1124, and also transmit the light rays of the first polarization state.

[0047] In the fifth embodiment, the polarized films of the first light splitting unit 1110 and the second light splitting unit 1120 have different optical effects on the light rays of the first polarization state and the second polarization state, which can reduce the interfering light rays in the first projection light beam 1114 and the second projection light beam 1124, so that the content of the first virtual image 1115 and the content of the second virtual image 1125 are clearer. The virtual image formed by the interfering light rays does not coincide with the first virtual image 1115 (and the second virtual image 1125), and the virtual image formed by the interfering light rays does not interfere with the driving personnel in identifying the content of the first virtual image 1115. This embodiment can improve the flexibility of the composition of multiple virtual images in the optical system 10 by setting the polarized film. The content of the first virtual image 1115 and the content of the second virtual image 1125 can be the same to correspond to a longer road section in the environment, further improving the navigation effect. The content of the first virtual image 1115 and the content of the second virtual image 1125 can be different, for example, the content of the first virtual image 1115 includes information of the transport vehicle 1000 (fuel, electricity, speed, etc.), and the second virtual image 1125 includes instruction signs (lane lines, indication arrows, etc.), so as to improve the understanding of the driving personnel on the transport vehicle 1000 and the road conditions.

[0048] In the case of no conflict, the features such as the number of the second light splitting unit 1120, the type of the first optical film layer 1113, and the type of the second optical film layer 1123 in each of the embodiments one, two, three, four, and five can be combined with each other in other embodiments.

[0049] Referring to FIG. 6, in the embodiment, the optical system 10 further comprises a beam folding module 130. The beam folding module 130 is arranged on the light path of the image source light beam. After the image source light beam is conducted to the beam folding module 130, the beam folding module 130 can reflect the image source light beam to change the light path of the image source light beam. After the image source light beam is folded by the beam folding module, the image source light beam can be conducted towards the beam expanding module 120. In the embodiment, the beam folding module 130 is arranged to make the light path of the image source light beam have more forms, so as to shorten the distance between the image source module 20 and the beam expanding module 120, and make the optical system 10 occupy smaller space.

[0050] The embodiment does not limit the type of the beam folding module 130. As an example, the beam folding module 130 can comprise at least one plane mirror, which can reflect the image source light beam and conduct the image source light beam to the beam expanding module 120. As another example, the beam folding module 130 can comprise at least one curved mirror (such as a free-form mirror, a concave mirror, etc.), which can reflect the image source light beam and correct the phase difference of the image source light beam, so as to make the virtual image formed by the image source light beam on the windshield 800 clearer and reduce the deformation degree of the virtual image.

[0051] In the embodiment, the beam splitting module 110 is arranged on the side of the windshield 800 where the projection imaging surface 810 is arranged (i.e. the side facing the cockpit 910) with the windshield 800 as a reference. The first incident surface 1117 of the first beam splitting unit 1110 of the beam splitting module 110 is arranged on the side of the first light-transmitting main body 1111 away from the windshield. The beam expanding module 120 is arranged on the side of the beam splitting module 110 away from the windshield 800, and the beam expanding module 120 is arranged opposite to the first incident surface 1117. The beam folding module 130 and the image source module 20 are arranged on the same side of the beam expanding module 120, and the beam folding module 130 is arranged between the image source module 20 and the windshield 800.

[0052] In the arrangement of the present embodiment, the light path of the image source light beam is substantially determined, specifically, the light path of the image source light beam between the image source module 20 and the beam folding module 130 and the light path of the image source light beam between the beam folding module 130 and the beam expanding module 120 are mutually included at an angle. The light path of the image source light beam between the image source module 20 and the beam folding module 130 and the light path of the image source light beam between the beam expanding module 120 and the light splitting module 110 are substantially parallel. The light path of the image source light beam between the beam expanding module 120 and the light splitting module 110 and the light path of the first reflected light beam 1116 are substantially perpendicular (in the present embodiment, the first light-transmitting body 1111 includes two isosceles right-angle prisms, the second light-transmitting body 1121 includes two isosceles right-angle prisms, and the image source light beam between the beam expanding module 120 and the light splitting module 110 is substantially perpendicular to the first incident surface 1117). Furthermore, the light path of the image source light beam between the beam expanding module 120 and the light splitting module 110, the light path of the first projection light beam 1114, and the light path of the second projection light beam 1124 are substantially parallel, and the light path of the first projection light beam 1114 and the light path of the second projection light beam 1124 are substantially perpendicular to the light path of the first reflected light beam 1116. The present embodiment sets the positions of the various modules of the optical system 10 so that the layout of the light path of the image source light beam is relatively compact, so that the entire optical system 10 and the projection display device 100 have a smaller volume.

[0053] The present embodiment provides an optical system 10, the light splitting module 110 in the optical system 10 at least includes a first light splitting unit 1110 and a second light splitting unit 1120, the first light splitting unit 1110 and the second light splitting unit 1120 can cooperate and form two virtual images, and the imaging distances of the two virtual images are different. The contents of the two virtual images formed by the first light splitting unit 1110 and the second light splitting unit 1120 can be freely set, and the contents of the two virtual images can be set to be the same. In the process of real scene fusion, virtual images with the same content can be formed at relatively close and relatively far positions at the same time, and the step of simulating different distances by the background software algorithm of the transport vehicle 1000 can be omitted, so as to avoid the influence of software algorithm delay on the real scene fusion effect, ensure the effect of real scene fusion, and enable the indication arrows or lane lines in the virtual image to correspond to longer road sections in the environment, thereby improving the navigation effect. The contents of the two virtual images can also be set to be different, so as to simultaneously provide more road information and information of the transport vehicle 1000 to the driver, thereby improving the understanding of the driver on the transport vehicle 1000 and the road conditions.

[0054] In this specification, certain terms are used to refer to particular units. As one of ordinary skill in the art will understand, different manufacturers can refer to a certain component by different names and / or different numbering schemes. Reference to a certain term in this specification is not intended to limit the component to which the term refers to particular units, but is intended to cover all components with equivalent functionality. As used in the specification and in the claims, the phrase "comprises" and variations thereof, such as "comprising" and "comprises," means "including but not limited to," and is intended to cover a non-exclusive inclusion. "Consisting essentially of" means including the elements listed after the term, and any other elements that do not materially affect the basic and novel characteristics of the composition or method. "Consisting of" means including the elements listed after the term, and no other elements.

[0055] In the description of the present application, the terms "upper", "lower", "front", "rear", "left", "right", "inner", "outer", and the like, indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, and are only used to simplify the description of the present application, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0056] In the present application, unless otherwise explicitly specified or limited, the terms "mounting", "connecting", "connecting", "fixing" and the like should be understood broadly. For example, it can be fixedly connected, or it can be detachably connected, or it can be integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements, or it can be only surface contact. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0057] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms is not necessarily for the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine the different embodiments or examples described in the present specification and the features of the different embodiments or examples without contradiction.

[0058] In addition, the terms "first", "second", etc. are used only for the purpose of description, and should not be understood as indicating or implying relative importance or implying the number of the technical features indicated. Therefore, the features defined as "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0059] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application, and are not limited thereto; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art will understand that the technical solutions described in the foregoing examples can still be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. An optical system, characterized in that: The optical system is applied to a projection display device having an image source module; the image source module is used to emit an image source light beam; The optical system includes a beam splitting module and a beam expanding module. The beam splitting module includes a first beam splitting unit and a second beam splitting unit arranged in parallel. The beam expanding module is suitable for being arranged on the optical path of the image source light beam. After the image source light beam passes through the beam expanding effect of the beam expanding module, it is reflected by the beam expanding module to the first beam splitting unit. The first beam splitting unit is used to transmit a portion of the image source light beam to form a first projection light beam, and transmit the first projection light beam to the target imaging carrier to form a first virtual image; the first beam splitting unit is also used to reflect a portion of the image source light beam to form a first reflected light beam, and transmit the first reflected light beam to the second beam splitting unit; The second beam splitting unit is used to reflect at least part of the first reflected light beam to form a second projection light beam, and transmit the second projection light beam to the target imaging carrier to form a second virtual image. The imaging distances of the first virtual image and the second virtual image are different.

2. The optical system according to claim 1, wherein The first light splitting unit includes a first light receiving surface, the first light receiving surface is provided with a first optical film layer, and the first optical film layer is used to reflect part of the image source light beam and transmit part of the image source light beam; The second light splitting unit includes a second light receiving surface. The first light receiving surface is provided with a second optical film layer. The second optical film layer is used to reflect at least a portion of the first reflected light beam.

3. The optical system according to claim 2, wherein: The first optical film layer is a semi-transparent and semi-reflective film; or / and, The first optical film layer is a polarizing film, which is used to transmit light in a first polarization state to form the first projection beam, and to reflect light in a second polarization state to form the first reflected beam. The first polarization state and the second polarization state are different.

4. The optical system according to claim 3, wherein The second optical film layer is a semi-transparent and semi-reflective film, and the semi-transparent and semi-reflective film is also used to transmit part of the first reflected light beam; There are multiple second spectroscopic units, and the multiple second spectroscopic units are arranged in sequence along the optical path of the first reflected light beam on one side of the first spectroscopic unit to receive the first reflected light beam in sequence; each second spectroscopic unit is used to reflect light to form a corresponding second virtual image, and to transmit light to the next second spectroscopic unit on the optical path of the first reflected light beam; the imaging distances of the multiple second virtual images formed by the multiple second spectroscopic units are different.

5. The optical system according to claim 3, wherein: The second optical film layer is a total reflection film.

6. The optical system according to claim 2, wherein: The first optical film layer is a polarizing film, and is used to transmit light of a first polarization state to form the first projection light beam, and to reflect light of a second polarization state to form the first reflected light beam, wherein the first polarization state and the second polarization state are different; The second optical film layer is a polarizing film, and the second optical film layer is used to reflect the light of the second polarization state to form the second projection light beam.

7. The optical system according to any one of claims 2 to 6, characterized in that The range of the incident angle of the image source light beam on the first optical film layer is: greater than or equal to 30° and less than or equal to 60°; or / and, The range of the incident angle of the first reflected light beam on the second optical film layer is: greater than or equal to 30° and less than or equal to 60°.

8. The optical system according to any one of claims 2 to 6, wherein: The first light splitting unit includes a first light-transmitting body, and the first light-receiving surface is defined inside the first light-transmitting body; The second light splitting unit includes a second light-transmitting body, the second light-receiving surface is defined inside the second light-transmitting body, and the second light-transmitting body and the first light-transmitting body are connected in parallel along the transmission direction of the first reflected light beam.

9. The optical system according to any one of claims 1 to 6, wherein: The optical system also includes a beam folding module, which is arranged on the optical path of the image source light beam. After the image source light beam passes through the folding action of the beam folding module, the optical path of the image source light beam is folded so that the image source light beam is transmitted to the beam expansion module.

10. The optical system according to claim 9, wherein: The beam folding module includes at least one of the following optical elements: a plane reflector and a curved reflector.

11. The optical system according to any one of claims 1 to 6, wherein: The beam expansion module includes at least one of the following optical elements: a concave reflector and a convex reflector.

12. A projection display device, characterized in that: include: An image source module, the image source module is used to emit an image source light beam; as well as The optical system according to any one of claims 1 to 11, wherein the optical system is located on the optical path of the image source light beam.

13. A transport vehicle, characterized in that: include: body; a windshield, the windshield being mounted on the body; as well as The projection display device according to claim 12, wherein the projection display device is used to project onto the windshield to form the first virtual image and the second virtual image.

Images