Head-up display device, shell assembly thereof and working frequency adjusting method

Abstract

The invention provides a head-up display device, a shell assembly thereof and a working frequency adjusting method, the shell assembly can comprise a dielectric substrate and a conductive skeleton, the conductive skeleton is embedded in the dielectric substrate, the conductive skeleton comprises a grounding interface and a radiation extension part, the grounding interface is exposed on the inner surface of the dielectric substrate, and the radiation extension part is exposed on the inner surface of the dielectric substrate. The grounding module is used for fixing an internal circuit board of the head-up display device and establishing a grounding path; the radiation extension part is electrically connected with the grounding interface and extends along the periphery of the dielectric substrate; wherein the radiation extension portion is configured to work as an antenna radiator to transmit and receive radio frequency signals when excited via a feed position near the ground interface.

Description

Technical Field

[0001] This disclosure relates to the field of electromagnetic shielding technology, and in particular to a head-up display device and its housing assembly, as well as a method for adjusting the operating frequency. Background Technology

[0002] Head-up displays (HUDs) are electronic devices that project key information into the user's field of vision and are widely used in automotive, aviation, and wearable devices. As these devices become more integrated and have more internal functional modules, they place extremely high demands on space utilization.

[0003] In the structural design of traditional head-up display (HUD) devices, the outer casing is the core basic structure, but it only undertakes the basic functions of mechanical protection and structural support. It is generally made of an insulating material substrate, which can only enclose and fix the core components such as internal circuit boards and optical modules. To achieve radio frequency (RF) signal transmission and reception, the device needs to be equipped with an independent antenna module. This independent antenna module requires separate installation space, which not only significantly reduces the layout space of other functional modules, but also makes it easy for RF signal transmission to be interfered with due to unreasonable installation position. At the same time, traditional outer casings lack an integrated grounding structure, and the grounding path of the circuit board has poor stability. It is easy for electromagnetic interference to be caused by loose grounding, which affects the overall working stability of the device. Summary of the Invention

[0004] This disclosure provides a head-up display device and its housing assembly, as well as a method for adjusting the operating frequency; it can solve the problems of the existing head-up display device housing having a single function, low space utilization due to independent antenna setting, poor grounding stability, non-adjustable antenna frequency band, and poor compatibility between electromagnetic shielding and antenna radiation.

[0005] The technical solution disclosed herein is implemented as follows: In a first aspect, this disclosure provides a housing assembly for a head-up display device, comprising: Dielectric matrix; A conductive framework, embedded in the dielectric matrix, and the conductive framework comprising: The grounding interface, exposed on the inner surface of the dielectric substrate, is used to secure the internal circuit board of the head-up display device and establish a grounding path; A radiating extension is electrically connected to the grounding interface and extends along the periphery of the dielectric substrate; wherein the radiating extension is configured to function as an antenna radiator to transmit and receive radio frequency signals when excited via a feed position near the grounding interface.

[0006] Secondly, this disclosure provides a head-up display device, including: The circuit board has an RF signal terminal and a ground terminal; The housing assembly as described in the first aspect; The circuit board is locked to the grounding interface by conductive fasteners, so that the radio frequency signal terminal is electrically coupled to the radiating extension.

[0007] Thirdly, this disclosure provides a method for adjusting the operating frequency of a head-up display device. The method includes providing the aforementioned housing assembly with multiple preset connection ports, determining a target communication frequency band, selecting a pair of ports from the multiple preset connection ports as a power supply point and a grounding point respectively to match the impedance characteristics of the target communication frequency band, assembling a circuit board to the housing assembly, and establishing an electrical connection through the selected ports.

[0008] This disclosure provides a head-up display device and its housing assembly, as well as a method for adjusting the operating frequency. The housing assembly breaks away from the traditional housing's single function of mechanical protection, simultaneously providing mechanical support, circuit board fixation, grounding path establishment, and antenna radiation. It integrates the previously separate housing, grounding connector, and antenna module into a single unit, significantly improving the internal space utilization of the head-up display device and eliminating the need for additional installation space for separate antennas and grounding components. The grounding interface in the conductive frame is exposed on the inner surface of the dielectric substrate and can be securely connected to the internal circuit board using conductive fasteners. Furthermore, the grounding interface and the radiating extension are electrically connected as an integrated structure, reducing connection nodes in a separate grounding structure, lowering contact resistance, enhancing the stability of the grounding path, and effectively avoiding electromagnetic interference problems caused by loose grounding. The radiating extension extends along the periphery of the dielectric substrate and can function as an antenna radiator when excited at the feed position near the grounding interface, eliminating the need for a separate antenna. This avoids the space occupied by a separate antenna and optimizes the antenna installation position through the overall structure of the housing, reducing interference during radio frequency signal transmission and ensuring the stability of the device's radio frequency communication. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of a head-up display device provided in this disclosure.

[0010] Figure 2 This is a schematic diagram of the structure of a housing assembly provided in this disclosure.

[0011] Figure 3 A flowchart illustrating the implementation process of a shell component structure provided in this disclosure.

[0012] Figure 4 This is a schematic diagram of the structure of a radiating extension provided in this disclosure.

[0013] Figure 5 This is a schematic diagram of a radiating extension serving as an antenna, as provided in this disclosure.

[0014] Figure 6This is a schematic diagram of a radiating extension with multiple preset connection ports as an antenna, as provided in this disclosure.

[0015] Figure 7 This is a schematic diagram showing the positional arrangement of multiple annular radiating extensions provided in this disclosure.

[0016] Figure 8 This is a schematic diagram of the structure of a housing assembly having multiple annular radiating extensions provided in this disclosure.

[0017] Figure 9 This is a schematic diagram of the outer shell assembly of a specific electromagnetic shielding component provided in this disclosure.

[0018] Figure 10 This is a schematic diagram of a grounding interface provided in this disclosure.

[0019] Figure 11 This is a schematic diagram of a grounding interface connected to a substrate, as provided in this disclosure.

[0020] Figure 12 This is a schematic diagram of another head-up display device provided in this disclosure.

[0021] Figure 13 A flowchart of a method for adjusting the operating frequency of a head-mounted display device provided in this disclosure. Detailed Implementation

[0022] The technical solutions in this disclosure will now be clearly and completely described with reference to the accompanying drawings.

[0023] In traditional head-up display (HUD) device designs, the outer casing typically serves only basic functions of mechanical protection and structural support. It is generally composed of an insulating substrate, merely enclosing and securing core components such as internal circuit boards and optical modules. However, to transmit and receive radio frequency (RF) signals, the device requires an additional, independent antenna module. These modules usually occupy dedicated installation space, which not only reduces the layout space for other functional modules but also makes RF signal transmission susceptible to interference if improperly positioned.

[0024] Meanwhile, the internal circuit board grounding of traditional head-up display (HUD) devices typically relies on a separate grounding connector. These connectors are separate from the outer casing, and during prolonged use or exposure to vibration and impact, grounding can easily become loose, affecting the circuit board's operational stability and potentially causing electromagnetic interference. Furthermore, the antennas of traditional HUD devices are mostly designed for fixed frequency bands. If the device needs to adapt to different communication requirements in different scenarios, the entire antenna module must be replaced, increasing the device's operating costs and reducing its versatility and flexibility.

[0025] In addition, in some scenarios where electromagnetic shielding is required, the electromagnetic shielding components and antenna radiators of traditional head-up display devices lack a reasonable structural design, which can easily lead to electromagnetic coupling interference. This can weaken the electromagnetic shielding effect and affect the antenna's radiation performance, resulting in a decrease in the device's communication quality and anti-interference capability.

[0026] Based on this, the present disclosure first provides a housing assembly for a head-up display device, such as Figure 1 The head-up display device shown in this embodiment includes a housing assembly 110, a circuit board 120, an optical projection module 130, a power module 140, and a sensor module 150. The housing assembly 110 serves as the basic support structure for the entire device, housing and fixing internal core components such as the circuit board 120 and the optical projection module 130. The circuit board 120 is the control and communication core of the device, integrating a central processing unit (CPU), radio frequency chip, memory, and other functional chips, enabling radio frequency signal transmission and reception, and device operation control. The optical projection module 130 projects the device's display information into the user's field of view, and includes a light source 131 and an optical path assembly 132. The power module 140 provides a stable power supply for the entire device. The sensor module 150 includes attitude sensors, distance sensors, etc., for collecting the device's operating status information and external environmental information.

[0027] In this system architecture, the housing assembly 110 not only needs to provide mechanical protection and component fixation, but also needs to provide a stable grounding path for the circuit board 120, and at the same time, it also needs to act as an antenna to transmit and receive radio frequency signals. Therefore, the structural design of the housing assembly 110 is the key to the realization of multi-functional integration of the entire device.

[0028] In some exemplary embodiments of this disclosure, such as Figure 2 As shown, the housing assembly 110 for the head-up display device includes a dielectric substrate 111 and a conductive skeleton 112, with the conductive skeleton 112 embedded inside the dielectric substrate 111, forming an integrated composite structure.

[0029] The dielectric substrate 111 is an insulating component whose main function is to provide support and fixation for the conductive frame 112, while preventing the conductive frame 112 from making electrical connections with other unnecessary components inside the equipment. The dielectric substrate 111 can be made of materials with good insulation properties and mechanical strength, such as epoxy resin, polycarbonate, and ABS engineering plastics. In practical applications, different materials can be selected according to the usage scenario of the equipment. For example, in the high-temperature environment of an automotive vehicle, high-temperature resistant epoxy resin can be selected.

[0030] The conductive frame 112 is a metal component. The material can be copper, aluminum alloy, stainless steel, or other metals with good conductivity and mechanical strength. Copper has good conductivity, which can reduce the loss during radio frequency signal transmission. Aluminum alloy has both light weight and good conductivity, making it suitable for scenarios with strict requirements on the weight of the equipment.

[0031] The conductive frame 112 includes a grounding interface 1121 and a radiating extension 1122. The grounding interface 1121 is exposed on the inner surface of the dielectric substrate 111, that is, the side surface facing the inside of the device. It is used to fix the internal circuit board 120 of the head-up display device and establish a grounding path. The radiating extension 1122 is electrically connected to the grounding interface 1121 and extends along the periphery of the dielectric substrate 111. When the feed position near the grounding interface 1121 is excited, the radiating extension 1122 can work as an antenna radiator to realize the reception and transmission of radio frequency signals.

[0032] In practical applications, the dielectric substrate 111 can be formed using injection molding. The conductive skeleton 112 is pre-placed in the injection mold, and then molten insulating material is injected into the mold. After the material cools and solidifies, an integrated structure is formed in which the conductive skeleton 112 is embedded in the dielectric substrate 111. This molding method can ensure the connection stability between the conductive skeleton 112 and the dielectric substrate 111, and prevent them from loosening and separating during equipment use.

[0033] Reference Figure 3 The structural implementation process of the housing assembly 110 may include: Step S301: Select suitable dielectric and metal materials to prepare preforms of dielectric substrate and conductive skeleton respectively.

[0034] Step S302: Place the conductive skeleton preform in the preset position of the injection mold, ensuring that the grounding interface faces the inside of the mold.

[0035] Step S303: Inject the molten dielectric material into the mold to cover the outer area of ​​the conductive skeleton preform.

[0036] Step S304: After the dielectric material cools and solidifies, demold to obtain the initial finished product of the shell component.

[0037] Step S305: Perform post-processing such as grinding and cleaning on the initial finished product to ensure that there is no dielectric material residue in the exposed area of ​​the grounding interface and no defects such as burrs on the surface of the radiating extension, and finally obtain the finished shell component.

[0038] like Figure 4As shown, in an embodiment of this disclosure, the radiating extension 1122 forms an annular geometry along the periphery of the dielectric substrate 111. The annular geometry is not a completely closed structure, but includes at least one physical breakpoint 11221 that divides the annular geometry into non-closed paths.

[0039] The ring geometry design increases the radiation area of ​​the radiating extension 1122, improving the efficiency of radio frequency signal transmission and reception. The physical breakpoint 11221 allows the radiating extension 1122 to form a current standing wave resonance in a predetermined frequency band. In a traditional closed loop antenna structure, current forms a circulating current within the loop, making it difficult to generate a stable standing wave resonance in a specific frequency band. The physical breakpoint 11221 breaks the closure of the loop structure, allowing the current to form a standing wave on a non-closed path, thereby enabling the transmission and reception of radio frequency signals in the predetermined frequency band.

[0040] For example, when the predetermined frequency band is the 2.4GHz Wireless Fidelity (Wi-Fi) communication band, the setting of the physical breakpoint 11221 can make the length of the non-closed path of the radiation extension 1122 match the electrical length corresponding to the center wavelength of the 2.4GHz band. At this time, the radiation extension 1122 can generate a stable current standing wave resonance in the 2.4GHz band, realizing efficient Wi-Fi signal transmission and reception. If the predetermined frequency band is the 5GHz Wi-Fi communication band, the length of the non-closed path can be changed by adjusting the number or position of the physical breakpoint 11221 to match the electrical length corresponding to the center wavelength of the 5GHz band.

[0041] like Figure 5 As shown, the position of the physical breakpoint 11221 is not randomly set, but is set such that the length of the conductive path from the feed position 1123 to the physical breakpoint 11221 corresponds to a quarter of the center wavelength of the predetermined frequency band.

[0042] In the field of antenna design, a quarter-wavelength conductive path is a common design scheme for achieving standing wave resonance. When the length of the conductive path is a multiple of one-quarter, one-half, or three-quarters of the center wavelength of the predetermined frequency band, a stable current standing wave can be formed on the conductive path, thereby realizing the radiation of radio frequency signals in that frequency band.

[0043] For example, if the center frequency of the predetermined frequency band is f0 and the corresponding center wavelength is λ0 (λ0=c / f0, where c is the propagation speed of electromagnetic waves in free space, approximately 3×10^8m / s), when the conductive path length from the feed position 1123 to the physical breakpoint 11221 is λ0 / 4, the radiation extension 1122 can form a fundamental resonance in the f0 frequency band; when the conductive path length is λ0 / 2, a second harmonic resonance can be formed; and when the conductive path length is 3λ0 / 4, a third harmonic resonance can be formed.

[0044] In practical applications, if the predetermined frequency band is the 900MHz Global System for Mobile Communications (GSM) communication band, its center wavelength λ0 is approximately 0.333m. In this case, the conductive path length from the feed position 1123 to the physical breakpoint 11221 can be set to 0.083m (i.e., λ0 / 4), so that the radiation extension 1122 can form a stable fundamental resonance in the 900MHz band, realizing the transmission and reception of radio frequency signals in this band. If it is necessary to cover both the 900MHz and 1800MHz GSM communication bands simultaneously, two physical breakpoints 11221 can be set on the annular geometry, so that the conductive path lengths from the feed position 1123 to the two physical breakpoints 11221 are 0.083m (corresponding to λ0 / 4 of the 900MHz band) and 0.166m (corresponding to λ0 / 4 of the 1800MHz band), respectively, thereby achieving dual-band signal coverage.

[0045] In some exemplary embodiments of this disclosure, such as Figure 6 As shown, the conductive frame 112 also includes a plurality of preset connection ports 1124 distributed at different positions of the radiation extension 1122, and these preset connection ports 1124 are all electrically connected to the radiation extension 1122.

[0046] The multiple preset connection ports 1124 are designed to be selectively used as main feed points, auxiliary feed points, or grounding points, thereby altering the effective electrical length or impedance characteristics of the antenna radiator and thus adjusting the antenna's operating frequency. In antenna design, the effective electrical length and impedance characteristics are key parameters determining its operating frequency. By changing the positions of the feed points and grounding points, the length of the current path in the radiating extension 1122, i.e., the effective electrical length, can be altered. Simultaneously, the antenna's input impedance can be adjusted to match the communication requirements of different frequency bands.

[0047] For example, when the antenna's operating frequency needs to be adjusted from 2.4 GHz to 5 GHz, a preset connection port 1124 on the radiating extension 1122 near the physical breakpoint 11221 can be selected as the main feed point, and another preset connection port 1124 near the ground interface 1121 can be selected as the ground point. In this case, the current flow path on the radiating extension 1122 will be shortened, the effective electrical length will be reduced, and the corresponding operating frequency will increase to 5 GHz. If the operating frequency needs to be reduced from 5 GHz to 2.4 GHz, a preset connection port 1124 away from the physical breakpoint 11221 can be selected as the main feed point, and a preset connection port 1124 away from the ground interface 1121 can be selected as the ground point. This extends the current flow path, increases the effective electrical length, and thus reduces the operating frequency.

[0048] In some examples, refer to Figure 7 and Figure 8 The conductive framework 112 may include multiple nested ring structures disposed on the aforementioned housing assembly 110. The specific number can be customized based on requirements, and will not be elaborated here.

[0049] Among the multiple preset connection ports 1124, the ports not selected for feeding or grounding are defined as tuning ports. Tuning ports can be used to connect passive components or switching components to shift the operating frequency band of the antenna by changing the load impedance.

[0050] Passive components can be selected from capacitors, inductors, resistors, etc., while switching components can be selected from RF switches, etc. Different passive components and switching states will bring about different load impedance changes, thus affecting the resonant frequency of the antenna. For example, when a capacitor with a capacitance of 1pF is connected to the tuning port, the antenna load impedance will be capacitive, and its resonant frequency will shift towards higher frequencies; when an inductor with a capacitance of 1nH is connected, the load impedance will be inductive, and the resonant frequency will shift towards lower frequencies; by switching between capacitors with different capacitance values ​​or inductors with different inductance values ​​using RF switches, rapid switching between multiple frequency bands can also be achieved.

[0051] In the application scenarios of in-vehicle head-up display devices, the device may need to be compatible with the 2.4GHz Wi-Fi band, the 5.8GHz in-vehicle Bluetooth band, and the 433MHz in-vehicle remote control band. In this case, a multi-position RF switch can be connected to the tuning port. Different positions of the switch are connected to passive components corresponding to different frequency bands. When the device needs to switch to a certain frequency band, it is only necessary to control the RF switch to switch to the corresponding position to quickly adjust the antenna's operating frequency band without replacing the antenna module, which greatly improves the device's versatility.

[0052] In some exemplary embodiments of this disclosure, such as Figure 9As shown, the housing assembly 110 also includes an electromagnetic shielding member 113, which is embedded in the back region of the dielectric substrate 111, that is, the region facing the outside of the device or away from the circuit board 120. The electromagnetic shielding member 113 is physically separated from the radiation extension 1122 and forms a coupling gap 114.

[0053] The electromagnetic shielding component 113 can be made of a metal with good electromagnetic shielding performance, such as copper or permalloy. Its main function is to shield electromagnetic interference signals from the external environment, preventing external interference signals from entering the equipment and affecting the operation of core components such as the circuit board 120. It can also shield electromagnetic radiation signals inside the equipment, avoiding electromagnetic pollution to the external environment. The coupling gap 114 is set to avoid excessive electromagnetic coupling between the electromagnetic shielding component 113 and the radiating extension 1122. If the two are in direct contact or the gap is too small, the electromagnetic shielding component 113 will absorb the radio frequency signals of the radiating extension 1122, affecting the radiation performance of the antenna; if the gap is too large, it will not achieve a good electromagnetic shielding effect.

[0054] In practical applications, the width of the coupling gap 114 can be set between 0.5mm and 2mm. For example, when the electromagnetic shielding component 113 is made of permalloy and the radiation extension 1122 is made of copper, the width of the coupling gap 114 can be set to 1mm. This can ensure the shielding effect of the electromagnetic shielding component 113 and avoid excessive absorption of the radio frequency signal of the radiation extension 1122.

[0055] In the application scenarios of aviation head-up display equipment, the electromagnetic interference of the external environment is quite complex. By setting electromagnetic shielding component 113 and coupling gap 114, the electromagnetic interference intensity inside the equipment can be reduced to below 10dB, while the radiation efficiency of the antenna can still be maintained above 85%, ensuring the communication quality and working stability of the equipment.

[0056] like Figure 10 and Figure 11 As shown, the grounding interface 1121 is constructed as a copper cylindrical bushing structure (outer diameter 8mm, inner diameter 4mm, length 2mm). The metal bushing has internal threads or through holes for receiving fasteners. The radial extension 1122 is constructed as a metal frame structure. The metal bushing and the metal frame are integrally connected before being embedded in the dielectric substrate 111.

[0057] The internal threads or through holes of the metal bushing can accommodate conductive fasteners such as bolts and screws, facilitating the fixed connection between the circuit board 120 and the grounding interface 1121. The material of the metal bushing can be the same as that of the radiating extension 1122 to ensure conductivity and connection stability between the two. Compared to a separate connection, the integrated connection design of the metal bushing and the metal frame reduces the contact resistance of the connection node, improves the conductivity efficiency of the grounding path, and enhances the mechanical strength of the overall structure, preventing loosening of the connection during equipment vibration or impact.

[0058] In actual processing, the metal bushing and metal frame can be integrally formed through processes such as stamping and welding. For example, a stamping process can be used to stamp a whole metal sheet into an integral conductive skeleton preform that includes a metal bushing and a metal frame, and then the preform is embedded into the dielectric substrate 111 through injection molding. This processing method can ensure the overall accuracy and connection stability of the conductive skeleton 112. In the application scenario of portable wearable head-up display devices, the device needs to be moved frequently. The integrally connected conductive skeleton 112 can keep the contact resistance of the grounding path below 10mΩ, which is much lower than the contact resistance of the separate connection (usually above 50mΩ), effectively improving the working stability of the circuit board 120.

[0059] The head-up display device housing assembly disclosed herein, through an integrated composite structure of dielectric substrate 111 and embedded conductive frame 112, overcomes the functional limitations of traditional housings, achieving functional integration of mechanical support, circuit board fixation, grounding path construction, and radio frequency signal transmission and reception. The conductive frame 112 includes a grounding interface 1121, a metal bushing structure, which can be securely connected to the internal circuit board 120 via conductive fasteners 180 to establish a reliable grounding path. Furthermore, the grounding interface 1121 is integrally connected to the radiating extension 1122, which is in the form of a metal frame, significantly reducing the connection nodes of a split structure and improving the electrical stability of the grounding path. The radiating extension 1122 forms a ring-shaped geometric structure along the periphery of the dielectric substrate 111. Its preset physical breakpoint 11221 can divide the ring structure into a non-closed path, and the breakpoint position corresponds to a conductive path length that is a quarter of the center wavelength of a predetermined frequency band. This enables the radiating extension 1122 to form a stable current standing wave resonance under feeding excitation, thereby acting as an antenna radiator to achieve the transmission and reception of radio frequency signals in a specific frequency band.

[0060] The housing assembly also features flexible frequency band adjustment capabilities and excellent electromagnetic compatibility performance. Multiple preset connection ports 1124 distributed on its conductive frame 112 can be switched as needed to become the main feed point, auxiliary feed point, or ground point, thereby changing the effective electrical length and impedance characteristics of the antenna radiator. Unselected ports can be used as tuning ports to connect passive components 160 or switching components 170, achieving precise shift of the antenna's operating frequency band. Meanwhile, a coupling gap 114 is reserved between the electromagnetic shielding component 113 embedded on the back of the dielectric substrate 111 and the radiating extension 1122, which can effectively shield external electromagnetic interference and block internal electromagnetic radiation, while also avoiding excessive loss of antenna performance of the radiating extension 1122 due to the shielding component. In addition, the integrated molding process ensures the connection stability between the dielectric substrate 111 and the conductive frame 112, providing core structural support for the integration of the device and multi-scenario adaptation.

[0061] Furthermore, this disclosure also provides a head-up display device, such as... Figure 12 As shown, the head-up display device 100 includes a circuit board 120 and the aforementioned housing assembly 110. The circuit board 120 has a radio frequency signal terminal 121 and a ground terminal 122. The circuit board 120 is locked to the ground interface 1121 by conductive fasteners 180, so that the radio frequency signal terminal 121 is electrically coupled to the radiation extension portion 1122. The head-up display device may also include an optical projection module 130, a power module 140, and a sensor module 150. The specific structures of the optical projection module 130, the power module 140, and the sensor module 150 can be referred to the diagram below. Figure 1 The explanation will not be repeated here.

[0062] The conductive fastener 180 can be selected from conductive bolts, conductive screws, etc., and its material can be conductive metals such as copper and stainless steel. While fixing the circuit board 120 to the grounding interface 1121, the conductive fastener 180 also enables the electrical connection between the grounding terminal 122 of the circuit board 120 and the grounding interface 1121, as well as the electrical coupling between the radio frequency signal terminal 121 and the radiation extension 1122. When the radio frequency chip of the circuit board 120 generates a radio frequency signal, the radio frequency signal is transmitted to the radiation extension 1122 through the radio frequency signal terminal 121. The radiation extension 1122 acts as an antenna radiator to transmit the radio frequency signal. When the radiation extension 1122 receives an external radio frequency signal, it transmits the signal to the radio frequency signal terminal 121, where it is processed by the radio frequency chip.

[0063] The assembly process of the head-up display device 100 may specifically include preparing the housing assembly 110 and the circuit board 120; checking the conductivity of the grounding interface 1121 and the radiating extension 1122 of the housing assembly 110; checking the soldering quality of the radio frequency signal terminal 121 and the grounding terminal 122 of the circuit board 120; placing the circuit board 120 on the inner surface of the dielectric substrate 111 of the housing assembly 110, aligning the grounding terminal 122 of the circuit board 120 with the grounding interface 1121, and aligning the radio frequency signal terminal 121 with the feed position 1123 of the radiating extension 1122; passing the conductive fastener 180 through the mounting hole of the circuit board 120 and screwing it into the internal thread or through hole of the grounding interface 1121, and tightening the conductive fastener 180 to achieve a fixed connection between the circuit board 120 and the housing assembly 110; and testing the grounding continuity between the circuit board 120 and the grounding interface 1121, as well as the coupling performance between the radio frequency signal terminal 121 and the radiating extension 1122, to ensure that the communication and grounding functions of the device are normal.

[0064] In some example implementations, the radio frequency signal terminal 121 of the circuit board 120 is connected to a ground interface 1121 of the conductive frame 112 as a feed point, and the ground terminal 122 of the circuit board 120 is connected to another adjacent ground interface 1121, so that the radiation extension 1122 operates in the mode of an inverted-FAntenna (IFA).

[0065] The inverted-F antenna is a commonly used miniaturized antenna structure with advantages such as compact structure, stable gain, and easy impedance matching, making it suitable for space-constrained electronic devices. In this operating mode, one part of the radiating extension 1122 acts as a radiating arm, and the other part acts as a grounding arm. After the radio frequency signal is input from the feed point, the current will form a specific distribution between the radiating arm and the grounding arm, thereby realizing the radiation of the radio frequency signal. For example, in vehicle head-up display devices, the radiating extension 1122 using the inverted-F antenna mode can cover the mobile communication frequency band from 700MHz to 2700MHz, and its internal space occupation is only one-third that of a traditional antenna, improving the space utilization of the device.

[0066] The radiating extension 1122 forms two asymmetrical radiating arms through physical breakpoint 11221, which are used to cover the communication needs of the high-frequency band and the low-frequency band, respectively.

[0067] In antenna design, the length of the radiating arm is positively correlated with the wavelength of the operating frequency band; the longer the radiating arm, the lower the corresponding operating frequency band; conversely, the shorter the radiating arm, the higher the corresponding operating frequency band. Therefore, by configuring the radiating extension 1122 with two asymmetrical radiating arms, the antenna can simultaneously cover the communication needs of both high and low frequency bands. For example, setting the length of one radiating arm to 0.2m corresponds to the 750MHz low-frequency band communication, and setting the length of the other radiating arm to 0.1m corresponds to the 1500MHz high-frequency band communication. In this way, the radiating extension 1122 can simultaneously achieve RF signal transmission and reception in both the 750MHz and 1500MHz dual-bands. In aviation head-up display devices, this dual-band coverage design allows the device to simultaneously adapt to both aviation-specific low-frequency communication bands and civilian high-frequency communication bands, improving the device's scenario adaptability.

[0068] In some example implementations, such as Figure 13 As shown, the method for adjusting the operating frequency of a head-up display according to an embodiment of this disclosure includes the following steps: Step S1301: Provide a housing assembly with multiple preset connection ports.

[0069] In this step, it is necessary to check the conductivity and connection stability of multiple preset connection ports 1124 of the housing assembly 110 in advance to ensure that each port can normally perform power feeding, grounding or tuning functions. At the same time, check the position of the physical breakpoint 11221 and the length of the conductive path of the radiating extension 1122 to ensure that its fundamental resonant frequency meets the design requirements.

[0070] Step S1302: Determine the target communication frequency band.

[0071] The determination of the target communication frequency band needs to be combined with the usage scenario of the head-up display device. For example, in the vehicle scenario, the target communication frequency band may be the 2.4 GHz Wi-Fi band and the 900 MHz GSM band; in the aviation scenario, the target communication frequency band may be the 150 MHz aviation-specific frequency band and the 2.4 GHz satellite communication frequency band; in the portable wearable scenario, the target communication frequency band may be the 5 GHz Wi-Fi band and the 2.4 GHz band corresponding to Bluetooth 5.0.

[0072] Step S1303: Select a specific pair of ports from multiple preset connection ports as the power supply point and grounding point respectively, in order to match the impedance characteristics of the target communication frequency band.

[0073] In this step, the corresponding effective electrical length and input impedance need to be calculated based on the center frequency and impedance requirements of the target communication band, and then a suitable preset connection port 1124 needs to be selected. For example, when the target communication band is 2.4GHz and the input impedance requirement is 50Ω, a preset connection port 1124 on the radiating extension 1122 that is one-third of the conductive path length from the physical breakpoint 11221 can be selected as the feed point, and a preset connection port 1124 that is closer to the grounding interface 1121 can be selected as the grounding point. At this time, the input impedance of the antenna can be matched to 50Ω, and the effective electrical length can also be adapted to the center wavelength of the 2.4GHz band.

[0074] Step S1304: Assemble the circuit board into the housing assembly and establish electrical connections through the selected ports.

[0075] In this step, following the assembly process of the head-up display device described above, the RF signal terminal 121 of the circuit board 120 is connected to the selected feed point, and the ground terminal 122 is connected to the selected ground point. At the same time, the corresponding passive component 160 or switching component 170 is connected to the tuning port as needed. After completing the electrical connection, the antenna's operating frequency and communication quality also need to be tested to ensure that it meets the requirements of the target communication frequency band.

[0076] In practical applications, taking the need for an in-vehicle head-up display device to switch from the 2.4GHz Wi-Fi band to the 5GHz Wi-Fi band as an example, first determine that the target communication band is 5GHz. Then, select the preset connection port 1124 on the radiating extension 1122 that is closer to the physical breakpoint 11221 as the feed point, and select another preset connection port 1124 that is closer to the ground interface 1121 as the ground point. At this time, the effective electrical length of the antenna is shortened and the operating frequency is increased to 5GHz. If it is also necessary to adapt to the 5.8GHz in-vehicle Bluetooth band, a capacitor with a capacitance of 0.5pF can be connected to the tuning port to further shift the antenna's operating frequency band to 5.8GHz, thus completing the rapid adjustment of the frequency band.

[0077] It should be noted that the technical solutions described in this disclosure can be combined arbitrarily as long as they do not conflict.

[0078] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A housing assembly for a head-up display device, characterized in that, include: Dielectric matrix; A conductive framework, embedded in the dielectric matrix, and the conductive framework comprising: The grounding interface, exposed on the inner surface of the dielectric substrate, is used to secure the internal circuit board of the head-up display device and establish a grounding path; A radiating extension is electrically connected to the grounding interface and extends along the periphery of the dielectric substrate; wherein the radiating extension is configured to function as an antenna radiator to transmit and receive radio frequency signals when excited via a feed position near the grounding interface.

2. The housing assembly of the head-up display device according to claim 1, characterized in that, The radiating extension forms a ring-shaped geometric structure along the periphery of the dielectric substrate; The ring geometry includes at least one physical breakpoint that divides the ring geometry into non-closed paths, so that the radiating extension can form a current standing wave resonance in a predetermined frequency band.

3. The housing assembly of the head-up display device according to claim 2, characterized in that, The physical break point is positioned such that the length of the conductive path from the feed location to the physical break point corresponds to a quarter of the center wavelength of the predetermined frequency band.

4. The housing assembly of the head-up display device according to claim 1, characterized in that, The conductive framework further includes: Multiple preset connection ports are distributed at different locations on the radial extension; The plurality of preset connection ports are configured to be selectively used as main feed points, auxiliary feed points or ground points to change the effective electrical length or impedance characteristics of the antenna radiator, thereby adjusting the operating frequency of the antenna.

5. The housing assembly of the head-up display device according to claim 4, characterized in that, The ports among the plurality of preset connection ports that are not selected as power supply or ground are defined as tuning ports; The tuning port is used to connect passive or switching components to shift the operating frequency band of the antenna by changing the load impedance.

6. The housing assembly of the head-up display device according to claim 1, characterized in that, The housing assembly also includes: An electromagnetic shielding component is embedded in the back region of the dielectric substrate; The electromagnetic shielding component and the radiation extension are physically separated and form a coupling gap.

7. The housing assembly of the head-up display device according to claim 1, characterized in that, The grounding interface is configured as a metal bushing having internal threads or through holes for receiving fasteners. The radiating extension is configured as a metal frame, and the metal bushing is integrally connected to the metal frame before being embedded in the dielectric substrate.

8. A head-up display device, characterized in that, include: The circuit board has an RF signal terminal and a ground terminal; The housing assembly as described in any one of claims 1 to 7; The circuit board is locked to the grounding interface by conductive fasteners, so that the radio frequency signal terminal is electrically coupled to the radiating extension.

9. The head-up display device according to claim 8, characterized in that, The RF signal terminal of the circuit board is connected to a ground interface of the conductive frame as a power supply point, and the ground terminal of the circuit board is connected to another adjacent ground interface, so that the radiating extension operates in inverted F antenna (IFA) mode.

10. The head-up display device according to claim 8, characterized in that, The radiating extension forms two asymmetrical radiating arms through the physical breakpoint, which are used to cover the communication needs of the high-frequency band and the low-frequency band, respectively.

11. A method for adjusting the operating frequency of a head-up display device, characterized in that, include: Provide the housing assembly as described in claim 5; Determine the target communication frequency band; Select a pair of ports from the plurality of preset connection ports as the power supply point and the grounding point, respectively, to match the impedance characteristics of the target communication frequency band; The circuit board is assembled to the housing assembly, and an electrical connection is established through the selected port.

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