Vehicle-mounted HUD projection system

Abstract

The utility model discloses a vehicle-mounted HUD projection system which comprises a host unit and at least one optical fiber scanning projection unit, a control unit and light source units in one-to-one correspondence with the optical fiber scanning projection units are arranged in the host unit, and light beams emitted by the light source units are coupled into a first optical fiber. The first optical fiber is optically connected with a second optical fiber of the optical fiber scanning projection unit, the control unit is electrically connected with the optical fiber scanner and the light source unit, the optical fiber scanning projection unit is installed on the front side of the center console and emits image light towards the windshield, and a semi-reflecting film is arranged at the position, used for receiving the image light, of the windshield. The semi-reflective film reflects the image light to the eyes of a driver, and the semi-reflective film transmits light outside the vehicle at the same time. Elements used for emitting image light are not provided with light source parts or heat dissipation parts, and the advantage that the optical fiber scanner is small in size is combined, so that the installation space occupied by the optical fiber scanning projection unit is extremely small.

Description

Technical Field

[0001] This application relates to the field of display technology, and more particularly to an in-vehicle HUD projection system. Background Technology

[0002] A vehicle HUD (Head-Up Display) is a commonly used electronic display device in the transportation industry. It is used to display information such as speed, engine speed, fuel consumption, tire pressure, navigation, and external smart devices in real time on the windshield in the driver's field of vision. This can avoid the visual operation changes caused by the driver alternating between looking at external targets and internal instruments, thereby preventing eye fatigue and improving driving safety.

[0003] Typically, vehicle head-up displays (HUDs) use projection equipment to emit image light, which is then reflected by the windshield to the driver's eyes. However, current projection equipment generally uses CRT (Cathode Ray Tube) projection systems, LCD (Liquid Crystal Display) projection systems, LCOS (Liquid Crystal Silicon) projection systems, or DLP (Digital Light Processor) projection systems. These devices generally have a significant size and also feature large heat dissipation structures. This necessitates reserving considerable installation space on the center console for the projection equipment. Furthermore, since the heat dissipation components of traditional projection equipment are integrated with the projection display components, effective heat dissipation becomes a challenge. Utility Model Content

[0004] This application provides a vehicle-mounted HUD projection system to at least overcome the technical problem that existing vehicle-mounted projection devices are large in size and difficult to install.

[0005] To achieve the aforementioned objectives, this application provides an in-vehicle HUD projection system, comprising a host unit and at least one fiber optic scanning projection unit. The host unit includes a control unit and a light source unit corresponding to each fiber optic scanning projection unit. The light beam emitted from the light source unit is coupled into a first optical fiber, which is optically connected to a second optical fiber of the fiber optic scanning projection unit. The control unit is electrically connected to both the fiber optic scanner and the light source unit, and is used to control the light source unit to emit modulated light and control the fiber optic scanner to perform two-dimensional scanning along a predetermined trajectory. The fiber optic scanning projection unit is mounted on the front side of the center console and emits image light toward the windshield. A semi-reflective film is provided at the position on the windshield where the image light is received. The semi-reflective film reflects the image light to the driver's eyes and simultaneously transmits light from outside the vehicle.

[0006] Fiber optic scanning projection units do not have light sources or heat dissipation structures, making them extremely small in size. They offer a wide range of installation options, minimally impacting the layout of existing center console components. Furthermore, two or more fiber optic scanning projection units can be installed according to actual needs. When two or more fiber optic scanning projection units are installed, each unit can project a complete image, or each unit can project a portion of a complete image. The images projected by two or more fiber optic scanning projection units are then stitched together on the semi-reflective film of the windshield to form a complete image.

[0007] The fiber optic scanning projection unit includes a first housing, one end of which is a light-emitting end. An imaging lens is mounted on the light-emitting end of the first housing, and a fiber optic scanner that emits image light to the outside through the imaging lens is disposed inside the first housing. This structure makes the fiber optic scanning projection unit an independent component encapsulated within the first housing. Optical fibers and signal transmission lines for connecting the light source unit and the control unit can be led out from the first housing. Optical connectors, such as optical plug-in structures, can also be installed in the first housing to facilitate convenient connection and disconnection of the fiber optic scanning projection unit from the connecting optical fibers and signal transmission lines, thereby enabling connection and disconnection with the light source unit and the control unit. This allows for convenient assembly and disassembly of the fiber optic scanning projection unit, enabling individual maintenance and replacement of the fiber optic scanning projection unit.

[0008] The light source unit includes a second housing containing multiple semiconductor lasers. The light beams emitted from the semiconductor lasers are coupled into a first optical fiber via a coupling lens. The emitting end of the first optical fiber connects to the input end of the second optical fiber of the fiber optic scanner corresponding to the light source unit. This structure makes the light source unit an independent component encapsulated within the second housing. Optical fibers and signal transmission lines for connecting the scanning projection unit and the control unit can be led out from the second housing. Optical connectors can also be installed in the second housing to facilitate convenient connection and disconnection of the fiber optic scanning projection unit from the connecting optical fibers and signal transmission lines, thereby enabling connection and disconnection with the scanning projection unit and the control unit. This allows for convenient assembly and disassembly of the light source unit, enabling individual maintenance and replacement of the light source unit.

[0009] The coupling lens can be a focusing lens or a collimating lens, or other optical devices capable of coupling the beam emitted from a semiconductor laser into an optical fiber to improve coupling efficiency. In a preferred embodiment, the coupling lens in this example is a focusing lens.

[0010] The fiber optic scanner includes a scanning actuator and a second optical fiber. The light-emitting end of the second optical fiber is fixedly mounted on the free end of the scanning actuator in a cantilevered manner. The scanning actuator is fixedly installed in the first housing. The free end of the scanner actuator performs two-dimensional scanning vibration under the drive of the driving signal.

[0011] The input end of the second optical fiber is connected to the output end of the first optical fiber. Of course, the second optical fiber of each fiber scanning projection unit is connected to the first optical fiber leading from the corresponding light source unit. In a specific embodiment, the second and first optical fibers can be an integrally formed structure, meaning the optical fiber receiving the light output from the light source and the optical fiber installed on the fiber scanner are the same fiber. However, this makes fiber deployment very difficult. Therefore, to reduce the difficulty of installation, the first and second optical fibers are two independent optical fibers connected by an optical connection structure. The second optical fiber is a component installed within the fiber scanning projection unit. One end of the first optical fiber is optically connected to the light source unit, and the other end is optically connected to the second optical fiber of the corresponding fiber scanning projection unit. To facilitate installation, the first optical fiber can be an independent component with optical connection structures at both ends; it can also be a component with one end fixedly installed within the light source unit and the other end having an optical connection structure; or it can be a component with one end fixedly installed within the fiber scanning projection unit and the other end having an optical connection structure. In this case, the first and second optical fibers can be the same optical fiber. Further optionally, the optical connection structure can be a ceramic ferrule or a connection structure formed by fiber optic fusion splicing.

[0012] Optionally, the scanning actuator is a piezoelectric ceramic actuator. Driven by a driving signal, the free end of the piezoelectric ceramic actuator vibrates at high frequency along a first direction to achieve line scanning, while its free end vibrates at low frequency along a second direction to achieve frame scanning. More preferably, a vibration sensor is provided inside the first housing for collecting forced vibration signals of the first housing. The vibration sensor collects forced vibration signals in both the first and second directions. The vibration sensor is electrically connected to a control unit. Based on the forced vibration signals in the first and second directions, the control unit generates a correction control signal to drive the fiber optic scanner, controlling the two-dimensional scanning of the fiber optic scanner to cancel out the interference of the forced vibration signal. This gives the fiber optic scanning projection unit good vibration resistance.

[0013] The control unit includes a processor, an image storage unit, a light source control module, a scan drive module, a readable storage medium, an image storage unit, and a first-in-first-out (FIFO) memory.

[0014] The vehicle terminal is electrically connected to the control unit. The image information to be displayed inside the vehicle terminal can be projected onto the semi-reflective film through the fiber optic scanning projection unit to provide information to the driver.

[0015] One or more technical solutions in the embodiments of this application have at least the following technical effects or advantages:

[0016] The main unit can be installed in any location according to actual working conditions. Since the main unit is not used for the final projection imaging, its installation location is flexible and will not affect the vehicle's interior design. Furthermore, the main heat-generating components in the projection system are the light source unit and the control unit, so the heat dissipation structure is also located in the main unit. The component used to emit image light is the fiber optic scanning projection unit, which connects to the light source unit via fiber optic cable. Therefore, it has neither a light source component nor a heat dissipation component. Combined with the small size of the fiber optic scanner itself, the fiber optic scanning projection unit occupies minimal installation space, allowing for flexible installation and minimal impact on the vehicle's interior space and the installation space of other vehicle components. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the connection structure between the host unit and the fiber optic scanning projection unit in this application;

[0018] Figure 2 A schematic diagram of the structure of the fiber optic scanning projection unit projecting image light onto the windshield;

[0019] Figure 3 This is a schematic diagram of the light source unit.

[0020] Figure 4 This is a schematic diagram of the fiber optic scanning projection unit. Detailed Implementation

[0021] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0022] like Figure 1 , Figure 2 As shown, this application provides an in-vehicle HUD projection system, which includes a host unit 100 and at least one fiber optic scanning projection unit 200.

[0023] The host unit 100 is equipped with a control unit and a light source unit 101 corresponding to the fiber optic scanning projection unit 200.

[0024] The light beam emitted from the light source unit 101 is coupled into the first optical fiber 1011, and the first optical fiber 1011 is optically connected to the second optical fiber 2032 of the optical fiber scanning projection unit 200.

[0025] The control unit is electrically connected to the fiber optic scanner 203 and the light source unit 101, respectively, and is used to control the light source unit 101 to emit modulated light and to control the fiber optic scanner 203 to perform two-dimensional scanning along a predetermined trajectory.

[0026] The fiber optic scanning projection unit 200 is installed on the front side of the center console and emits image light toward the windshield. A semi-reflective film is provided at the position of the windshield for receiving the image light. The semi-reflective film reflects the image light to the driver's eyes and transmits light from outside the vehicle at the same time.

[0027] The fiber optic scanning projection unit 200 does not have a light source or heat dissipation structure, therefore it is extremely small in size, has a wide range of installation options, minimally affects the layout design of existing center console components, and can be configured with two or more fiber optic scanning projection units 200 according to actual needs. When two or more fiber optic scanning projection units 200 are installed, each fiber optic scanning projection unit 200 can project a complete image, or each fiber optic scanning projection unit 200 can project a portion of a complete image. The images projected by two or more fiber optic scanning projection units 200 are stitched together on the semi-reflective film of the windshield to form a complete image.

[0028] The main unit 100 can be installed in any location within the vehicle body, such as the engine compartment, center console housing, trunk, or passenger compartment, without restriction. Within the passenger compartment, it can be installed in the space under the seat or in the armrest box. The main unit 100 can be installed in any location according to actual working conditions. Since the main unit 100 is not used for final projection imaging, its installation location is flexible and will not affect the vehicle's interior design. Furthermore, the main heat-generating components in the projection system are the light source unit 101 and the control unit; therefore, the heat dissipation structure is also located in the main unit 100. The component used to emit image light is the fiber optic scanning projection unit 200, which is connected to the light source unit 101 via fiber optic cable. Therefore, it has neither a light source component nor a heat dissipation component. Combined with the small size of the fiber optic scanner 203, the fiber optic scanning projection unit 200 occupies minimal installation space, making its installation location flexible and having minimal impact on the vehicle's interior space and the installation space of other vehicle components. This provides the technical basis for deploying multiple projection imaging components within the vehicle body, allowing for the installation of multiple projection imaging components according to different application scenarios.

[0029] This application embodiment establishes a one-to-one correspondence between the light source unit and the fiber optic scanning projection unit in the host unit, and the control unit is electrically connected to each fiber optic scanning projection unit and each light source unit respectively. It controls the light source unit to emit light and controls the fiber optic scanning projection unit to perform two-dimensional scanning, thereby achieving scanning imaging display. This application embodiment realizes the application of fiber optic scanning projection to the vehicle field, thus meeting various needs in vehicle projection scenarios. Furthermore, the deployment of the light source unit and fiber optic scanning projection unit in this application embodiment facilitates component maintenance and replacement in vehicle projection scenarios.

[0030] like Figure 3As shown, the fiber optic scanning projection unit 200 includes a first housing 201, one end of which is a light-emitting end. An imaging lens 202 is disposed at the light-emitting end of the first housing 201. An fiber optic scanner 203, which emits image light to the outside through the imaging lens 202, is disposed inside the first housing 201. This structure makes the fiber optic scanning projection unit 200 an independent component encapsulated within the first housing 201. Optical fibers and signal transmission lines for connecting the light source unit 101 and the control unit can be led out from the first housing 201. Optical connectors, such as optical plug-in structures, can also be disposed in the first housing 201 to facilitate convenient connection and disconnection of the fiber optic scanning projection unit 200 from the connecting optical fibers and signal transmission lines, thereby enabling connection and disconnection with the light source unit 101 and the control unit. This facilitates the convenient assembly and disassembly of the fiber optic scanning projection unit 200, allowing for individual maintenance and replacement of the fiber optic scanning projection unit 200.

[0031] like Figure 4 As shown, the light source unit 101 includes a second housing 1012, within which multiple semiconductor lasers 1013 are disposed. The light beams emitted from the semiconductor lasers 1013 are coupled to a first optical fiber 1011 via a coupling lens 1014. The light-emitting end of the first optical fiber 1011 is connected to the light-inlet end of the second optical fiber 2032 of the fiber optic scanner 203 corresponding to the light source unit 101. This structure makes the light source unit 101 an independent component encapsulated within the second housing 1012. Optical fibers and signal transmission lines for connecting the scanning projection unit 200 and the control unit can be led out from the second housing 1012. Optical connectors can also be provided in the second housing 1012 to facilitate convenient connection and disconnection between the fiber optic scanning projection unit 200 and the connecting optical fibers and signal transmission lines, thereby enabling connection and disconnection with the scanning projection unit 200 and the control unit. This allows for convenient assembly and disassembly of the light source unit 101, enabling individual maintenance and replacement of the light source unit 101.

[0032] The coupling lens 1014 can be a focusing lens or a collimating lens 1015, or other optical devices capable of coupling the beam emitted from the semiconductor laser 1013 into the optical fiber to improve coupling efficiency. As a preferred embodiment, the coupling lens 1014 in this embodiment is a focusing lens.

[0033] In this embodiment, three semiconductor lasers 1013 are disposed within the second housing 1012. However, it is understood that the number of semiconductor lasers 1013 can also be any number, such as two, four, six, or seven. Furthermore, the housing of the fiber optic scanner 203 is provided with a collimating lens 1015 and a filter 1016 corresponding to each semiconductor laser 1013. The collimating lens 1015 and the filter 1016 are located in the optical path of the corresponding semiconductor laser 1013. The collimating lens 1015 is used to collimate the beam emitted by that semiconductor laser 1013, and the filter 1016 is used to reflect the collimated beam emitted by the corresponding semiconductor laser 1013 to the focusing lens and transmit the beams emitted by other semiconductor lasers 1013, thereby combining the beams emitted by each semiconductor laser 1013 into a single laser beam. The combined laser beam is then focused by the focusing lens and coupled into the optical fiber. The above structure allows different light source units 101 to have different emitted colors and brightness. The number, color, and number of semiconductor lasers 1013 inside the corresponding scanning projection unit 200 can be determined according to the needs of the light source unit 101.

[0034] The semiconductor laser 1013 is red, green, or blue (R, G, or B). In a preferred embodiment, the light source unit 101 is a colored light source unit 101, with the three semiconductor lasers 1013 being red, green, and blue (R, G, and B, respectively). Three filters 1016 are arranged parallel to each other, each filter 1016 reflecting the beam emitted from its corresponding semiconductor laser 1013 by 90° before it exits to the focusing lens and transmits beams emitted from other semiconductor lasers 1013. Alternatively, two or more semiconductor lasers 1013 of the same color can be disposed within the housing to increase the energy density of the light source. For example, if six semiconductor lasers 1013 are disposed within the housing, two of each semiconductor laser 1013 are red, green, or blue (R, G, or B).

[0035] like Figure 3 As shown, the fiber optic scanner 203 includes a scanning actuator 2031 and a second optical fiber 2032. The light-emitting end of the second optical fiber 2032 is fixedly mounted on the free end of the scanning actuator 2031 in a cantilevered manner. The scanning actuator 2031 is fixedly installed inside the first housing 201. The free end of the scanner actuator performs two-dimensional scanning vibration under the drive of the driving signal.

[0036] The light-inlet end of the second optical fiber 2032 is connected to the light-outlet end of the first optical fiber 1011. Of course, the second optical fiber 2032 of each optical fiber scanning projection unit 200 is connected to the first optical fiber 1011 leading from the light source unit 101 corresponding to that optical fiber scanning projection unit 200. In a specific embodiment, the second optical fiber 2032 and the first optical fiber 1011 can be an integrally formed structure, that is, the optical fiber receiving the light output from the light source and the optical fiber installed on the optical fiber scanner 203 are the same optical fiber. However, this makes the fiber layout very difficult. Therefore, to reduce the difficulty of installation and layout, the first optical fiber 1011 and the second optical fiber 2032 are two independent optical fibers, connected by an optical connection structure. The second optical fiber 2032 is a component installed within the optical fiber scanning projection unit 200. The first optical fiber 1011 is optically connected at one end to the light source unit 101 and at the other end to the second optical fiber 2032 of the corresponding optical fiber scanning projection unit 200. For ease of installation, the first optical fiber 1011 can be an independent component with optical connection structures at both ends; it can also be a component with one end fixedly installed inside the light source unit 101 and the other end having an optical connection structure; or it can be a component with one end fixedly installed inside the optical fiber scanning projection unit 200 and the other end having an optical connection structure. In this case, the first optical fiber 1011 and the second optical fiber 2032 can be the same optical fiber. Further optionally, the optical connection structure can be a ceramic ferrule or a connection structure formed by optical fiber fusion splicing.

[0037] Specifically, because the optical energy density at the fiber optic connector is relatively high, dust accumulation at the connector can easily lead to ablation. The optical connection structure of this embodiment can also include a lens (e.g., a collimating device) between the first optical fiber 1011 and the second optical fiber 2032. Under the same sealing conditions, this reduces the optical energy density at the fiber optic connector, minimizing the impact of dust on the optical connection structure and reducing the occurrence of ablation.

[0038] Optionally, the scanning actuator 2031 is a piezoelectric ceramic actuator. Driven by a driving signal, the free end of the piezoelectric ceramic actuator vibrates at high frequency along a first direction to achieve line scanning, while its free end vibrates at low frequency along a second direction to achieve frame scanning. More preferably, a vibration sensor is provided inside the first housing for collecting forced vibration signals of the first housing. The vibration sensor collects forced vibration signals in the first direction and the second direction, respectively. The vibration sensor is electrically connected to a control unit. The control unit generates a correction control signal based on the forced vibration signals in the first and second directions to drive the fiber optic scanner 203, controlling the two-dimensional scanning of the fiber optic scanner 203 to cancel the interference of the forced vibration signals. This gives the fiber optic scanning projection unit 200 good shock resistance.

[0039] The control unit includes a processor, an image storage unit, a light source control module, a scan drive module, a readable storage medium, an image storage unit, and a first-in-first-out (FIFO) memory.

[0040] The readable storage medium stores a marking signal for marking the scanning direction of the fiber cantilever of the second fiber 2032 in three-dimensional space. The storage medium also stores a program that, when executed by a processor, performs the following steps:

[0041] An electrical control signal (i.e. a drive signal) is sent to the scanning drive module to drive the fiber scanner 203, and to control the fiber cantilever in the fiber scanner 203 to perform scanning motion along a predetermined two-dimensional scanning trajectory (e.g., helical scanning, raster scanning, Lissajous scanning).

[0042] Starting from the moment the image output start signal is received, the image data of the currently displayed image is read from the image storage unit according to the pixel scanning order corresponding to the marker signal;

[0043] The image data of the currently displayed image is written into the first-in-first-out (FIFO) memory according to the pixel scanning order;

[0044] An electrical control signal is sent to the light source control module to control the light source unit 101. The light source unit 101 is controlled to output the light corresponding to each pixel in the currently displayed image in sequence according to the image data in the FIFO, so that the light output by the light source is completely in line with the optical fiber scanning trajectory to form an image on the projection surface.

[0045] Specifically, the light source control module outputs a light source modulation signal according to the received control signal to modulate each semiconductor laser 1013 in the light source unit 101. The light generated by each semiconductor laser 1013 in the light source unit 101 is combined by the coupling lens 1014 to generate the light corresponding to each pixel in the image one by one.

[0046] The vehicle terminal is electrically connected to the control unit. The image information to be displayed inside the vehicle terminal can be projected onto the semi-reflective film through the fiber optic scanning projection unit 200 to provide information to the driver.

[0047] It should be noted that the above embodiments are illustrative of this application and not limiting of it, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The words “comprising” or “including” do not exclude the presence of elements or steps not listed in the claims. The words “a” or “an” preceding an element do not exclude the presence of a plurality of such elements. The use of the words first, second, and third, etc., does not indicate any order and these words can be interpreted as names.

[0048] All features disclosed in this specification, except for mutually exclusive features, can be combined in any way.

[0049] Any feature disclosed in this specification (including any appended claims, abstract, and drawings) may be replaced by other equivalent or similar features, unless specifically stated otherwise. That is, unless specifically stated otherwise, each feature is merely one example of a series of equivalent or similar features.

[0050] This application is not limited to the specific embodiments described above. This application extends to any new features or combinations disclosed in this specification, as well as any new steps or combinations of any new methods or processes disclosed.

Claims

1. A vehicle-mounted HUD projection system, characterized in that, The system includes a main unit and at least one fiber optic scanning projection unit. The main unit contains a control unit and a light source unit corresponding to each fiber optic scanning projection unit. The light beam emitted from the light source unit is coupled into a first optical fiber, which is optically connected to a second optical fiber of the fiber optic scanning projection unit. The control unit is electrically connected to both the fiber optic scanner and the light source unit, and is used to control the light source unit to emit modulated light and control the fiber optic scanner to perform two-dimensional scanning along a predetermined trajectory. The fiber optic scanning projection unit is mounted on the front side of the center console and emits image light toward the windshield. A semi-reflective film is provided at the position on the windshield where the image light is received. The semi-reflective film reflects the image light to the driver's eyes and simultaneously transmits light from outside the vehicle.

2. The vehicle-mounted HUD projection system as described in claim 1, characterized in that, When the number of installed fiber optic scanning projection units is two or more, Each fiber optic scanning projection unit emits a complete image. Alternatively, each fiber optic scanning projection unit may emit a portion of a complete image, and the images emitted by two or more fiber optic scanning projection units may be stitched together on the semi-reflective film of the windshield to form a complete image.

3. The vehicle-mounted HUD projection system as described in claim 1, characterized in that, The vehicle terminal is electrically connected to the control unit, and the image information to be displayed inside the vehicle terminal is projected onto the semi-reflective film through the fiber optic scanning projection unit.

4. The vehicle-mounted HUD projection system as described in claim 1, characterized in that, The fiber optic scanning projection unit includes a first housing, one end of which is a light-emitting end. An imaging lens is provided at the light-emitting end of the first housing, and a fiber optic scanner that emits image light to the outside through the imaging lens is provided inside the first housing.

5. The vehicle-mounted HUD projection system as described in claim 4, characterized in that, The light source unit includes a second housing, in which multiple semiconductor lasers are disposed. The light beams emitted by the semiconductor lasers are coupled into a first optical fiber through a coupling lens. The light-emitting end of the first optical fiber is connected to the light-inlet end of the second optical fiber of the optical fiber scanner corresponding to the light source unit.

6. The vehicle-mounted HUD projection system as described in claim 5, characterized in that, A coupling lens is a focusing or collimating lens that couples the beam emitted from a semiconductor laser into an optical fiber.

7. The vehicle-mounted HUD projection system as described in claim 4, characterized in that, The fiber optic scanner includes a scanning actuator and a second optical fiber. The light-emitting end of the second optical fiber is fixedly mounted on the free end of the scanning actuator in a cantilevered manner. The scanning actuator is fixedly installed in the first housing. The free end of the scanner actuator performs two-dimensional scanning vibration under the drive of the driving signal.

8. The vehicle-mounted HUD projection system as described in claim 7, characterized in that, The second optical fiber and the first optical fiber are integrally formed. Alternatively, the first and second optical fibers can be two independent optical fibers connected by an optical connection structure to guide light.

9. A vehicle-mounted HUD projection system as described in claim 7, characterized in that, The scanning actuator is a piezoelectric ceramic actuator. Under the drive signal, the free end of the piezoelectric ceramic actuator vibrates at a high frequency along the first direction to achieve line scanning, and at the same time, the free end vibrates at a low frequency along the second direction to achieve frame scanning.

10. A vehicle-mounted HUD projection system as described in claim 9, characterized in that, A vibration sensor is provided inside the first housing for collecting forced vibration signals of the first housing. The vibration sensor collects forced vibration signals in the first direction and forced vibration signals in the second direction, respectively. The vibration sensor is electrically connected to the control unit.

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