Head-mounted display device

Abstract

A head-mounted display device comprises a support, a circuit board and a metal frame. The circuit board is connected to the support, and a radio frequency circuit is arranged on the circuit board. The metal frame is connected to the support, all or at least part of the metal frame is a radiator, a gap is kept between the radiator and the support, and the radiator is electrically connected with the radio frequency circuit. In the application, the metal frame is multiplexed as the radiator, so that the function of the antenna can be realized, extra space in the equipment does not need to be occupied for arranging the antenna, the space can be saved, the miniaturization design of the equipment is facilitated, the structure of the antenna can be simplified, the antenna arrangement is facilitated, and the realization of light weight of the equipment is facilitated. Besides, when a plurality of radiators are arranged, all positions on the metal frame can be used as the radiators, and the positions of the radiators have relatively large selectivity, so that a relatively large distance can be obtained between two adjacent radiators, and the isolation degree is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electronic products, in particular to a head-mounted display device. BACKGROUND

[0002] With the development of head-mounted display technology, there are more and more antenna modules in the head-mounted display device, which requires more layout space. However, the space in the head-mounted display device is limited, and the increase of the antenna modules will result in smaller and smaller antenna clearance, affecting the radiation performance of the antenna, and the distance between the antennas is getting smaller and smaller, and the isolation problem between the antennas is becoming more and more prominent.

[0003] In the traditional head-mounted display device, the antenna mostly transmits data by using a flexible printed circuit (FPC), the FPC has messy wiring and needs to occupy more space. At the same time, the antenna using the FPC is greatly affected by the surrounding metal devices and high-speed signal wiring, and the interference problem is serious, which is difficult to meet the demand of larger data flow service. SUMMARY

[0004] Therefore, the present application provides a head-mounted display device, which proposes an antenna design scheme based on the current head-mounted display device form, aiming to solve the problems of large space occupied by the antenna and poor isolation between the antennas in the existing head-mounted display device.

[0005] In a first aspect, the embodiments of the present application provide a head-mounted display device, which comprises a support, a circuit board and a metal frame. The circuit board is connected to the support, and a radio frequency circuit is arranged on the circuit board. The metal frame is connected to the support, at least part of the metal frame is a radiator, a gap is maintained between the radiator and the support, and the radiator is electrically connected to the radio frequency circuit.

[0006] In the present application, the radiator is part of the metal frame, that is, by multiplexing all or part of the metal frame as a radiator, the function of the antenna can be realized, so that no additional space inside the device is needed for arranging the antenna, which can greatly save space, is conducive to the miniaturization design of the device, and can also simplify the structure of the antenna, facilitate the arrangement of the antenna, and is also conducive to the realization of the lightweight of the device. In addition, when multiple radiators are provided, since the radiator is part of the metal frame, each position on the metal frame can be used as a radiator, that is, the position of the radiator has great selectivity, so that the optimal antenna design can be performed as much as possible under the limited structural space.

[0007] In a possible implementation, the metal frame continuously surrounds the outside of the support, or at least part of the metal frame continuously surrounds the outside of the support. In this way, the metal frame is a continuous structure in the circumferential direction of the support, that is, the metal frame has no gaps or the like, so that the metal frame has high structural strength. Part of the metal frame and the support can be spaced apart to form a radiator, and the radiator can be electrically connected to the radio frequency circuit at a specified position. The metal frame can be connected to the support at positions on both sides of the gap, so that part of the metal frame can form a slot antenna.

[0008] In a possible implementation, the metal frame has a plurality of gaps, and the radiator includes parts of the metal frame adjacent to the gaps. In this way, one end of the radiator close to the gap is an open end, which is relatively open, that is, the open end is not grounded. In this embodiment, the ground can be the support. The other end of the radiator away from the open end is a closed end, which can be grounded. In this embodiment, the closed end is connected to the support. The radiator and the radio frequency circuit can form a wire antenna.

[0009] In a possible implementation, the width of the gap is between 1.5 mm and 5 mm, so that the metal frame has good radiation performance and high structural strength.

[0010] In a possible implementation, the metal frame includes a decoupling branch, the decoupling branch is arranged between at least two adjacent radiators, and the two ends of the decoupling branch are spaced apart from the adjacent radiators through the gaps. The decoupling branch is electrically connected to the support. In this way, the decoupling branch can reduce the coupling between the two adjacent radiators, so that the isolation between the two adjacent radiators can be improved when the distance between the two adjacent radiators is small.

[0011] In a possible implementation, at least two radiators are located on the same side of the metal frame, and the decoupling branch is arranged between the two adjacent radiators on the same side of the metal frame. In this way, the decoupling branch can concentrate the energy coupled between the two adjacent radiators to the decoupling branch, so that the energy coupling interference between the two adjacent radiators can be reduced, and the isolation between the two adjacent radiators can be improved.

[0012] In a possible implementation, a distance between two adjacent radiators located on the same side of the metal frame is between 28mm and 40mm, and a length of the decoupling branch is between 24mm and 34mm. According to the current embodiment, the distance between the two adjacent radiators located on the same side of the metal frame and the length of the decoupling branch are within the corresponding size ranges, so that the coupling energy of the two adjacent radiators can be coupled to the decoupling branch as much as possible, thereby avoiding being coupled to the radiators, and thus the isolation between the two adjacent radiators can be effectively improved, and the antenna can have a better isolation.

[0013] In a possible implementation, the metal frame includes a top portion, a bottom portion, and two side portions, and the top portion, the bottom portion, and the two side portions form a ring shape. The radiators include a first radiator and a second radiator, the first radiator is located on the side portion, and the second radiator is located on the bottom portion. The first radiator can excite a first electric field, and the second radiator can excite a second electric field, and a direction of the first electric field and a direction of the second electric field are perpendicular.

[0014] In some embodiments, the first radiator and the second radiator can also constitute any one or a combination of WLAN antennas, BT antennas, BLE antennas, GNSS antennas, SLE antennas, cellular TDD antennas, cellular FDD antennas, etc. In some embodiments, the number of the first radiator and the second radiator can be one or more. For example, two first radiators can be provided, one first radiator can be arranged on one side of the metal frame, and the other first radiator can be arranged on the other side of the metal frame. Any one of the two first radiators can constitute an antenna with WLAN function and / or BT function, so that the device has the function of wireless connection and / or Bluetooth connection. The second radiator can be located at the bottom of the metal frame. For example, the second radiator can constitute a BLE antenna, and the device can establish interconnection with the external handle through the BLE antenna. Generally, when the user operates the handle, the user usually operates below the neck. Relative to the positions of the metal frame, the handle is closer to the position at the bottom of the metal frame. Therefore, in order to realize the interconnection between the antenna constituted by the second radiator and the antenna in the handle and better transmission of data, the signal transmission energy value between the second radiator and the handle should be as large as possible. In the embodiment, by arranging the second radiator at the bottom of the metal frame, the proportion of the lower hemisphere energy of the BLE antenna pattern is larger, so as to improve the signal strength transmitted to the handle end and ensure the stability of the interconnection between the handle and the second radiator. Since the antenna constituted by the second radiator (such as the aforementioned BLE antenna) needs to maintain wireless communication with the external handle at all times, and cannot be time-division with the antenna constituted by the first radiator (such as the aforementioned WLAN antenna), not only high isolation is required between the two antennas constituted by the first radiators, but also high isolation is required between the first radiator and the second radiator. For example, when the first radiator constitutes a WLAN antenna and the second radiator constitutes a BLE antenna, high isolation is required between the WLAN antenna and the BLE antenna. Therefore, in the embodiment, the two first radiators can be arranged at two sides of the metal frame respectively, so as to have a large distance between the two first radiators, thereby improving the isolation between the two first radiators. At the same time, the first radiator can excite a first electric field, and the second radiator can excite a second electric field. The direction of the first electric field and the direction of the second electric field are perpendicular. The polarization direction of the antenna constituted by the first radiator can be perpendicular to the polarization direction of the antenna constituted by the second radiator. The antenna modes are orthogonal, so as to improve the isolation between the antenna constituted by the first radiator and the antenna constituted by the second radiator.

[0015] In a possible implementation, the first radiator is provided with a first feeding point for electrically connecting with the radio frequency circuit, and a distance between the first feeding point and a center of the first radiator is between 2mm and 5mm, so that the polarization direction of the first radiator is consistent or close to consistent with the first direction, and the polarization direction of the first radiator is perpendicular to the polarization direction of the second radiator, thereby improving the isolation between the first radiator and the second radiator.

[0016] In a possible implementation, the second radiator is provided with a second feeding point, and a distance between the second feeding point and a center of the second radiator is between 3mm and 5mm, so that the polarization direction of the second radiator is consistent or close to consistent with the second direction, and the polarization direction of the second radiator is perpendicular to the polarization direction of the first radiator, thereby improving the isolation between the second radiator and the first radiator.

[0017] In a possible implementation, the metal frame includes a top portion, a bottom portion and two side portions, and the top portion, the bottom portion and the two side portions enclose a ring shape. The radiators include a third radiator and a fourth radiator, the third radiator is located at the top portion, and the fourth radiator is located at the bottom portion. The fourth radiator is provided with a slit. The third radiator can excite a third electric field, and the fourth radiator can excite a fourth electric field. The direction of the third electric field is perpendicular to the direction of the fourth electric field.

[0018] In some embodiments, the third radiator and the fourth radiator can also constitute any one or a combination of WLAN antennas, BT antennas, BLE antennas, GNSS antennas, SLE antennas, cellular TDD antennas, cellular FDD antennas, and the like. In some embodiments, the number of the third radiator and the fourth radiator can be one or more. For example, two third radiators are provided, and any one of the two third radiators can constitute an antenna with WLAN function and / or BT function, and the fourth radiator can constitute a BLE antenna. Since the two third radiators are located on the same side of the metal frame and adjacent to each other, in order to improve the isolation between the two third radiators, the aforementioned decoupling branch can be arranged between the two third radiators, so that a larger isolation can be obtained between the adjacent antennas. In addition, the third radiator can excite a third electric field, and the fourth radiator can excite a fourth electric field, and the direction of the third electric field is perpendicular to the direction of the fourth electric field. Since the third radiator is arranged at the top of the metal frame, the direction of the third electric field is consistent with the second direction. The fourth radiator is arranged at the bottom of the metal frame, and in the case where the metal frame is not provided with a slit, the direction of the fourth electric field is consistent with the second direction. In the present embodiment, a slit is arranged at a corresponding position on the fourth radiator, for example, a slit is arranged at the center position of the fourth radiator, which can affect the electric field distribution of the fourth radiator, so that the direction of the fourth electric field is consistent with the first direction, thereby realizing that the direction of the fourth electric field is perpendicular to the direction of the third electric field, and improving the isolation between the fourth radiator and the third radiator.

[0019] In a possible implementation, the width of the slit is between 1.5mm and 5mm, so that the direction of the fourth electric field is perpendicular to the direction of the third electric field, and the structural strength of the metal frame can be ensured.

[0020] In a possible implementation, the electromagnetic signal corresponding to the frequency band received and transmitted by the second radiator or the fourth radiator is 2400MHz-2480MHz. The frequency band corresponds to the BLE antenna, and stable connection with the external handle can be realized.

[0021] In a possible implementation, the material of the support is metal, so that the stability of the structure of the head-mounted display device can be improved.

[0022] In a possible implementation, the metal frame and the support are integrally formed, that is, there is no clear connection boundary between the metal frame and the support, and the metal frame and the support can be formed at the same time in one process, so that the preparation process can be simplified, and the structural reliability between the metal frame and the support can be ensured.

[0023] In a possible implementation, the radiator and the radio frequency circuit are electrically connected through a metal piece. In this way, the metal piece with a small size can be used to electrically connect the radiator and the radio frequency circuit, so that the internal space of the device can be greatly saved, and the problem that the FPC is easily interfered by surrounding metal devices and high-frequency signals can be avoided.

[0024] In a possible implementation, the metal piece includes a spring or a screw. The spring or the screw can be used to reliably electrically connect the radiator and the radio frequency circuit, facilitate the connection operation, and has a small size, so that the internal space of the device can be saved, and the device can be designed to be small.

[0025] It should be understood that the foregoing general description and the following detailed description are only exemplary and are not limiting to the present application. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiments will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0027] Figure 1 A schematic view of a part of a metal frame in a head-mounted display device as an embodiment of the present application forms a radiator;

[0028] Figure 2 A front view of a head-mounted display device as an embodiment of the present application;

[0029] Figure 3 A schematic view of a part of a metal frame in a head-mounted display device as another embodiment of the present application forms a radiator;

[0030] Figure 4 A front view of a head-mounted display device as another embodiment of the present application;

[0031] Figure 5 A schematic view of an electric field distribution when there is no decoupling branch between two adjacent radiators;

[0032] Figure 6 A S-parameter diagram when there is no decoupling branch between two adjacent radiators;

[0033] Figure 7 A schematic view of an electric field distribution when there is a decoupling branch between two adjacent radiators;

[0034] Figure 8 A S-parameter diagram when there is a decoupling branch between two adjacent radiators;

[0035] Figure 9 A schematic diagram of the electric field distribution of the radiator in the use state of the head-mounted display device provided in this application embodiment;

[0036] Figure 10 for Figure 2 Electric field distribution diagram of the second radiator;

[0037] Figure 11 for Figure 2 Electric field distribution of the first radiator in one mode;

[0038] Figure 12 for Figure 2 Electric field distribution of the first radiator in another mode;

[0039] Figure 13 This application provides an S-parameter diagram of a first radiator and a second radiator according to one embodiment.

[0040] Figure 14 for Figure 4 Electric field distribution diagram of the fourth radiator;

[0041] Figure 15 The S-parameter diagrams of the third and fourth radiators provided in one embodiment of this application are shown.

[0042] Figure label:

[0043] 1-Metal frame;

[0044] 11-Radiator;

[0045] 111 - First radiator;

[0046] 112 - Second radiator;

[0047] 113 - Third radiator;

[0048] 114 - Fourth radiator;

[0049] 114a - Slit;

[0050] 115-Radiator Three;

[0051] 116-Radiator Four;

[0052] 1a - Top;

[0053] 1b - Bottom;

[0054] 1c - Side;

[0055] 12-Break;

[0056] 13-Decoupled branch;

[0057] 2-bracket;

[0058] 3-circuit board;

[0059] 4-metal piece;

[0060] G-gap;

[0061] 10-radiator one;

[0062] 20-radiator two;

[0063] X-first direction;

[0064] Y-second direction. DETAILED DESCRIPTION

[0065] In order to better understand the technical solutions of the present application, the embodiments of the present application are described in detail below in conjunction with the drawings.

[0066] It should be clear that the described embodiments are only some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0067] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0068] It should be understood that the term "and / or" used herein is only to describe the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects are a "or" relationship.

[0069] In the description of the present application, unless otherwise expressly specified and limited, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance; unless otherwise specified or explained, the term "multiple" means two or more; the terms "connection", "fixation" and the like should be understood in a broad sense, for example, "connection" can be fixedly connected, or can be detachably connected, or integrally connected, or electrically connected; it can be directly connected, or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0070] With the development of head-mounted display technology, the number of antenna modules in the head-mounted display device is increasing, and more space is needed for arrangement. However, the space in the head-mounted display device is limited, resulting in a smaller and smaller distance between the antennas, and a poor isolation between the antennas, which is difficult to meet the demand for larger data flow services. For example, the antennas in the existing head-mounted display device generally need to be installed independently. For example, the antennas can be fixed to the inner wall of the device shell by clamping, gluing or other methods, or fixed to the corresponding structure in the shell. When the number of antennas is large, a large amount of space inside the device is occupied, and at the same time, the antennas are distributed closely, the isolation between the antennas is seriously deteriorated, and it is difficult to meet the demand for larger data flow services. In addition, for the antennas in the head-mounted display device, flexible printed circuit (FPC) is mostly used to transmit data. The FPC wiring is messy and needs to occupy more space. At the same time, the antenna using FPC is greatly affected by the surrounding metal devices and high-speed signal wiring, and the interference problem is serious.

[0071] The head-mounted display device provided by an embodiment of the present application can include a mixed reality (MR) device, an augmented reality (AR) device, a virtual reality (VR) device, etc. The specific type of the head-mounted display device is not limited in the embodiment. Figure 1 FIG. 1 is a schematic view of a part of a metal frame in a head-mounted display device according to an embodiment of the present application, which constitutes a radiator, and FIG. 2 is a schematic view of a head-mounted display device according to an embodiment of the present application. Figure 1 The head-mounted display device provided by an embodiment of the present application includes a support 2, a circuit board 3 and a metal frame 1. The support 2 can be used as the skeleton of the head-mounted display device and can carry many structures and devices. For example, the support 2 can be provided with a camera module, a sensor, a mirror eye distance adjustment module, etc. In an embodiment, the support 2 can be made of metal, so as to improve the stability of the structure of the head-mounted display device.

[0072] The circuit board 3 can be a printed circuit board (PCB), or a flexible circuit board, or other boards that can be used to arrange circuits. In the embodiment, the circuit board 3 can be connected to the support 2, and the circuit board 3 can be provided with a radio frequency circuit. The radio frequency circuit can transmit electromagnetic waves through the antenna.

[0073] The metal frame 1 is a structural member wrapped outside the support 2. It can be understood that the metal frame 1 is made of metal material, such as aluminum alloy, magnesium alloy, etc. The metal frame 1 has a stable structure, which can improve the structural reliability of the head-mounted display device, and can also provide effective protection for the internal devices and structures. In addition, the metal frame 1 made of aluminum alloy, magnesium alloy and other metal materials also has a lighter weight, which makes the head-mounted display device have a good appearance while also facilitating lightweight design.

[0074] The metal frame 1 can be connected to the support 2. In an embodiment, the metal frame 1 can be fixedly connected to the support 2 by screws or the like, or can be fixedly connected to the support 2 by buckling. In an embodiment, the material of the support 2 can also be metal. The metal frame 1 and the support 2 can be integrally formed, that is, there is no clear connection boundary between the metal frame 1 and the support 2. The metal frame 1 and the support 2 can be formed at the same time in one process, thereby simplifying the preparation process and ensuring better structural reliability between the metal frame 1 and the support 2.

[0075] Referring to Figure 1 , the metal frame 1 can be formed as a radiator 11. The radiator 11 and the support 2 maintain a gap G to avoid short circuit, and the radiator 11 is electrically connected to the radio frequency circuit. The radiator 11 can realize electromagnetic wave radiation by being connected to the radio frequency circuit, that is, the cooperation of the radiator 11 and the radio frequency circuit can constitute an antenna. The radiator 11 in this embodiment is not a separate component manufactured separately. The radiator 11 can be part of the metal frame 1, or the entire metal frame 1 can serve as a radiator. That is, by reusing the entire metal frame 1 or at least part of the metal frame 1 as a radiator 11, the function of an antenna can be realized, thereby saving space and facilitating miniaturization of the device.

[0076] In an embodiment, referring to Figure 1 When the radiator 11 is at least part of the metal frame 1, the number of radiators 11 can be one or more. When there are multiple radiators 11, each position on the metal frame 1 can serve as a radiator 11, that is, the position of the radiator 11 has greater selectability, thereby enabling optimal antenna design in limited structural space.

[0077] In an embodiment, by multiplexing the metal frame 1, the radiator 11 can be designed as a linear antenna or a slot antenna, and multiple antennas can be arranged on one metal frame 1. For example, the radiator 11 can constitute a WLAN antenna, a BT antenna, a BLE antenna, a GNSS antenna, a SLE antenna, a TDD antenna, an FDD antenna, etc. The cellular TDD antenna and the cellular FDD antenna can cover the medium and high frequency bands, such as B3\B1\B7\B40\B41, etc. When the radiator 11 is provided with multiple radiators, each radiator 11 can constitute one or more of the above-mentioned antennas. For example, when the radiator 11 is provided with two radiators, one of the radiators can constitute a WLAN antenna and a BT antenna, and the other radiator can also constitute a WLAN antenna and a BT antenna. For another example, when the radiator 11 is provided with three radiators, the three radiators 11 can constitute a WLAN antenna, a BT antenna and a BLE antenna, respectively. For another example, when the radiator 11 is provided with six radiators, the six radiators 11 can constitute a WLAN antenna, a BT antenna, a BLE antenna, a GNSS antenna, a cellular TDD antenna and a cellular FDD antenna, respectively. Of course, in other embodiments, the radiator 11 can have other numbers, and each radiator 11 can constitute different types of antennas or combinations of antennas, which will not be described here.

[0078] In an embodiment, Figure 2 A front view of the head-mounted display device according to an embodiment of the present application is shown in FIG. 1. As shown in FIG. 1, the head-mounted display device comprises a support 2, a circuit board 3, a metal frame 1, a radiator 11, a metal piece 4, a display 5 and a metal piece 6. Figure 2 The radiator 11 and the radio frequency circuit can be electrically connected through the metal piece 4, and the radio frequency circuit can feed the radiator 11 through the metal piece 4. Since the circuit board 3 is fixed on the support 2 and the radiator 11 is formed by multiplexing the metal frame 1, the radiator 11 can be close to the radio frequency circuit on the circuit board 3, and there is no need to use FPC wiring between the radiator 11 and the radio frequency circuit. The radiator 11 and the radio frequency circuit can be electrically connected through the small metal piece 4, thereby greatly saving the internal space of the device, and avoiding the problem that the FPC is easily disturbed by surrounding metal devices and high-frequency signals.

[0079] In one embodiment, the metal component 4 has a stable structure. Exemplarily, the metal component 4 may include a spring or a screw. The spring or screw enables a reliable electrical connection between the radiator 11 and the radio frequency circuit, facilitating connection operations. Furthermore, the small size of the spring or screw helps save internal space and achieves miniaturized device design. Of course, in other embodiments, the metal component 4 may also be other metal parts, such as pins, rivets, springs, etc.

[0080] In one embodiment, reference is made to... Figure 1 and Figure 2 The metal frame 1 can continuously surround the outside of the bracket 2. In this embodiment, the metal frame 1 has a continuous structure in the circumferential direction of the bracket 2, that is, there are no gaps or other features on the metal frame 1, thereby ensuring that the metal frame 1 has high structural strength. A gap G can be reserved between a part of the metal frame 1 and the bracket 2 to form a radiator 11. A designated position on the radiator 11 can be electrically connected to the radio frequency circuit. The parts of the metal frame 1 located at both ends of the gap G can be connected to the bracket 2. Thus, a part of the metal frame 1 can be used to form a slot antenna. There can be one slot antenna or multiple slot antennas constructed at different positions on the metal frame 1. The specific number depends on the wireless functions required by the device.

[0081] In one embodiment, at least a portion of the metal frame 1 can be continuously wound around the outside of the support 2, while other portions of the metal frame 1 can be discontinuous, for example, having features such as a gap 12. The portion of the metal frame 1 continuously wound around the support 2 can also be used to construct the aforementioned slot antenna; the specific construction method is as described above and will not be repeated here.

[0082] In one embodiment, Figure 3 A schematic diagram showing a portion of the metal frame 1 in a head-mounted display device according to another embodiment of this application constituting a radiator 11, see reference. Figure 3 The metal frame 1 can have multiple slits 12, and the radiator 11 can include the portion of the metal frame 1 adjacent to the slits 12. That is, the end of the radiator 11 closest to the slit 12 is an open end, which is relative to ground; that is, the open end is not grounded. In this embodiment, "ground" can be the support 2. The end of the radiator 11 furthest from the open end is a closed end, which can be grounded. In this embodiment, the closed end is connected to the support 2. In one embodiment, the closed end of the radiator 11 can be connected to the support 2 by a connecting rib, which can be integrally formed from the metal frame 1 and the metal support 2. The radiator 11 and the radio frequency circuit can together constitute a line antenna.

[0083] In an embodiment, the line antenna and the slot antenna can exist simultaneously. For example, as described above, for the scheme in which part of the metal frame 1 is continuously wound on the outside of the support 2, and the other part of the metal frame 1 is discontinuously wound on the outside of the support 2, the part of the metal frame 1 that is continuously wound on the outside of the support 2 can be configured as the aforementioned slot antenna, and the part of the metal frame 1 that is discontinuously wound on the outside of the support 2 can be configured as the line antenna.

[0084] It should be noted that, with reference to Figure 3 , the width H of the break 12 needs to meet certain size requirements to configure an antenna with desired antenna performance. If the width of the break 12 is too small, it is difficult to achieve better antenna performance, for example, more energy of the antenna can be coupled to the adjacent metal to cause greater loss. If the width of the break 12 is too large, the structural strength of the metal frame 1 can be reduced. Therefore, in the present embodiment, the width H of the break 12 can be between 1.5 mm and 5 mm, for example, the width H of the break 12 can be 1.5 mm, 2 mm, 3 mm, 4 mm, or 5 mm, so as to achieve better radiation performance of the antenna and ensure the structural strength of the metal frame 1.

[0085] In an embodiment, if the distance between two adjacent antennas configured on the metal frame 1 is close, the isolation between the two adjacent antennas is small, which affects the antenna radiation performance. In the present embodiment, with reference to Figure 4 , the metal frame 1 can be configured to form a decoupling branch 13, the decoupling branch 13 can be arranged between at least two adjacent radiators 11, and the two ends of the decoupling branch 13 are spaced apart from the adjacent radiators 11 by the break 12, and the decoupling branch 13 is electrically connected to the support 2 to achieve grounding. By arranging the decoupling branch 13, the coupling between the two adjacent antennas can be reduced, and the isolation can be improved when the two antennas are adjacent.

[0086] It can be understood that the size of the head-mounted display device is very limited, with reference to Figure 4 , when at least two radiators 11 are arranged on the same side of the metal frame 1, the distance between the two adjacent radiators 11 is close, and if the two adjacent radiators 11 do not have any decoupling device, electromagnetic wave interference will occur between the two adjacent radiators 11, which reduces the antenna performance. Figure 5 is a schematic diagram of the electric field distribution when the two adjacent radiators 11 do not have the decoupling branch 13, with reference to Figure 5 , for the convenience of description, the two radiators 11 in Figure 5 can be defined as radiator one 10 and radiator two 20, Figure 5The radiator 10 shown is located to the left of the radiator 20. The energy of the radiator 10 can couple to the radiator 20, causing interference and resulting in poor isolation. Figure 6 The S-parameter plot is shown when there is no decoupling branch 13 between two adjacent radiators 11, referring to... Figure 6 , Figure 6 Curve a shown in the figure is the isolation curve between radiator 10 and radiator 20. In the 2.4G mode, the isolation between radiator 10 and radiator 20 is only 14dB, which is a small isolation.

[0087] Therefore, in one embodiment provided in this application, reference is made to Figure 4 At least two radiators 11 are located on the same side of the metal frame 1, and a decoupling stub 13 is disposed between two adjacent radiators 11 located on the same side of the metal frame 1. The decoupling stub 13 can concentrate the energy coupled between two adjacent radiators 11 onto the decoupling stub 13, thereby reducing the energy coupling interference between two adjacent radiators 11 and improving the isolation between two adjacent radiators 11. Figure 7 This is a schematic diagram of the electric field distribution when there is a decoupling branch 13 between two adjacent radiators 11, referring to... Figure 7 For ease of explanation, we can define Figure 7 The two radiators 11 in the image are radiator three 115 and radiator four 116. Figure 7 The radiator 3 115 shown is located to the left of the radiator 4 116. There is a decoupling stub 13 between the radiator 3 115 and the radiator 4 116. The energy of the radiator 3 115 can be coupled to the decoupling stub 13 without being coupled to the radiator 4 116. Thus, the isolation between the radiator 3 115 and the radiator 4 116 is improved through the decoupling stub 13, which effectively solves the electromagnetic interference generated between the radiator 3 115 and the radiator 4 116 and can ensure that the radiator 3 115 and the radiator 4 116 can work normally. Figure 8 The S-parameter diagram is shown when there is a decoupling branch 13 between two adjacent radiators 11, referring to... Figure 8 , Figure 8 Curve b shown in the figure is the isolation curve between radiator three 115 and radiator four 116. In 2.4G mode, the isolation between radiator three 115 and radiator four 116 can reach 31dB. That is to say, by setting decoupling stub 13, the isolation between radiator three 115 and radiator four 116 can be significantly improved.

[0088] It should be noted that the distance between the two adjacent radiators 11 on the same side of the metal frame 1 and the length of the decoupling branch 13 need to meet certain size requirements to play a better decoupling effect of the decoupling branch 13, and at the same time play a better radiation performance of the antenna. In an embodiment, referring to Figure 4 , the distance L1 between the two adjacent radiators 11 on the same side of the metal frame 1 can be between 28mm and 40mm, and the length L2 of the decoupling branch 13 can be between 24mm and 34mm. Based on the current embodiment, the distance L1 between the two adjacent radiators 11 on the same side of the metal frame 1 and the length L2 of the decoupling branch 13 are within the above corresponding size range, the coupling energy of the two adjacent radiators 11 can be coupled to the decoupling branch 13 as much as possible, thereby avoiding coupling to the radiators 11, and thus the isolation between the two adjacent radiators 11 can be effectively improved, and the antenna can have a better isolation. In an embodiment, the distance L1 between the two adjacent radiators 11 on the same side of the metal frame 1 can be 29mm, and the length L2 of the decoupling branch 13 can be 26mm, and the width of the gap 12 between the decoupling branch 13 and any side of the radiator 11 can be 1.5mm. In an embodiment, the distance L1 between the two adjacent radiators 11 on the same side of the metal frame 1 can be 32mm, and the length L2 of the decoupling branch 13 can be 28mm, and the width of the gap 12 between the decoupling branch 13 and any side of the radiator 11 can be 2mm.

[0089] In an embodiment, referring to Figure 2 , the metal frame 1 includes a top 1a, a bottom 1b and two sides 1c, and the top 1a, the bottom 1b and the two sides 1c form a ring shape. For ease of description, the metal frame 1 can be defined to have a first direction X and a second direction Y, the first direction X can be equivalent to the direction of the user's eyes distribution, and the second direction Y can be equivalent to the direction of the user's forehead and mouth distribution. The top 1a and the bottom 1b of the metal frame 1 are located on both sides of the second direction Y, and the two sides 1c of the metal frame 1 are located on both sides of the first direction X. The size of the metal frame 1 in the first direction X is greater than the size in the second direction Y, so that the metal frame 1 can present a ring shape similar to an ellipse or a racetrack. Among them, the top 1a of the metal frame 1 is located above the user's eye, and the bottom 1b of the metal frame 1 is located below the user's eye.

[0090] Among them, referring to Figure 2The radiator 11 includes a first radiator 111 and a second radiator 112. The first radiator 111 can be located on the side portion 1c of the metal frame 1. In some embodiments, the first radiator 111 and the second radiator 112 can also constitute any one or a combination of multiple of the following antennas: a WLAN antenna, a BT antenna, a BLE antenna, a GNSS antenna, a SLE antenna, a cellular TDD antenna, a cellular FDD antenna, etc. In some embodiments, the number of the first radiator 111 and the second radiator 112 can be one or more. For example, two first radiators 111 can be provided, one first radiator 111 can be arranged on one side portion 1c of the metal frame 1, and the other first radiator 111 can be arranged on the other side portion 1c of the metal frame 1. Any one of the two first radiators 111 can constitute an antenna with WLAN function and / or BT function, so that the device has the function of wireless connection and / or Bluetooth connection. The second radiator 112 can be located on the bottom portion 1b of the metal frame 1. For example, the second radiator 112 can constitute a BLE antenna, and the frequency band corresponding to the BLE antenna can be 2400MHz-2480MHz. The device can establish interconnection with the external handle through the BLE antenna. Generally, when the user operates the handle, the user usually operates below the neck. Relative to the positions of the metal frame 1, the handle is closer to the bottom portion 1b of the metal frame 1. Therefore, in order to realize the interconnection between the antenna constituted by the second radiator 112 and the antenna in the handle and better transmission of data, the signal transmission energy value between the second radiator 112 and the handle should be as large as possible. In the embodiment, by arranging the second radiator 112 on the bottom portion 1b of the metal frame 1, the proportion of the lower hemisphere energy of the BLE antenna directional diagram is larger, so as to improve the signal strength transmitted to the handle end and ensure the stability of the interconnection between the handle and the second radiator 112. Figure 9 The head-mounted display device provided in the embodiment of the present application has the electric field distribution of the radiator 11 in the use state. Figure 9 It can be known that, since the second radiator 112 in the embodiment is arranged on the bottom portion 1b of the metal frame 1, the electric field distribution of the bottom portion 1b of the head-mounted display device is more, which is beneficial to the signal transmission between the second radiator 112 and the external handle.

[0091] Since the antenna composed of the second radiator 112 (such as the BLE antenna described above) needs to maintain wireless communication with the external handle at all times, it cannot be time-division with the antenna composed of the first radiator 111 (such as the WLAN antenna described above), so not only is high isolation required between the two antennas composed of the first radiator 111, but high isolation between the first radiator 111 and the second radiator 112 is also considered. For example, when the first radiator 111 forms a WLAN antenna and the second radiator 112 forms a BLE antenna, high isolation between the WLAN antenna and the BLE antenna needs to be ensured. To this end, in the present embodiment, the two first radiators 111 can be located on two side portions 1c of the metal frame 1, respectively, so that the two first radiators 111 have a large distance therebetween, thereby improving the isolation between the two first radiators 111. At the same time, the first radiator 111 can excite a first electric field, and the second radiator 112 can excite a second electric field, the direction of the first electric field being perpendicular to the direction of the second electric field. Figure 10 For Figure 2 the electric field distribution of the second radiator 112 in the middle, refer to Figure 10 , the second radiator 112 is located at the bottom 1b of the metal frame 1 and is configured as a slot antenna, and the electric field direction of the second radiator 112 is consistent with the second direction Y. Figure 11 For Figure 2 the electric field distribution of the first radiator 111 in one mode, Figure 11 exemplarily shows the electric field distribution of the first radiator 111 in the 5G mode, from Figure 11 it can be seen that the electric field distribution direction of the first radiator 111 is consistent with the first direction X. Figure 12 For Figure 2 the electric field distribution of the first radiator 111 in another mode, Figure 12 exemplarily shows the electric field distribution of the first radiator 111 in the 2.4G mode, from Figure 12 it can be seen that the electric field distribution direction of the first radiator 111 is consistent with the first direction X. That is, the first radiator 111 works in any mode, and the electric field direction is consistent with the first direction X. Thus, the first electric field direction of the first radiator 111 is perpendicular to the second electric field direction of the second radiator 112, the polarization direction of the antenna composed of the first radiator 111 is perpendicular to the polarization direction of the antenna composed of the second radiator 112, and the antenna modes are orthogonal, thereby improving the isolation between the antenna composed of the first radiator 111 and the antenna composed of the second radiator 112.

[0092] Figure 13 For the S parameter diagram of the first radiator 111 and the second radiator 112 provided by an embodiment of the present application, refer to Figure 13 , Figure 13The curve c shown in FIG. 1 is an isolation S12 curve between the two first radiators 111, and the curve d is an isolation S23 curve between any one of the first radiators 111 and the second radiator 112. In the present application, the two first radiators 111 can be symmetrically distributed on the two side portions 1c of the metal frame 1, and the two first radiators 111 have the same structure and the same radiation mode. The isolation curve between any one of the two first radiators 111 and the second radiator 112 is the same. Therefore, in the present embodiment, the above-mentioned S23 curve (the isolation between one of the first radiators 111 and the second radiator 112) is taken as an example for description. As can be seen from the curve c in FIG. 1, the two first radiators 111 have a high isolation, which can reach close to 17 dB. At the same time, as can be seen from the curve d, the first radiator 111 and the second radiator 112 have a high isolation, which can reach 22 dB. Figure 13 As can be seen from the curve c in FIG. 1, the two first radiators 111 have a high isolation, which can reach close to 17 dB. At the same time, as can be seen from the curve d, the first radiator 111 and the second radiator 112 have a high isolation, which can reach 22 dB.

[0093] In an embodiment, the first radiator 111 is arranged on the side portion 1c of the metal frame 1, and the first radiator 111 is provided with a first feeding point for electrical connection with the radio frequency circuit. The position of the first feeding point affects the polarization direction of the first radiator 111. In the present embodiment, the distance between the first feeding point and the center of the first radiator 111 is between 2 mm and 5 mm. That is, the position of the first feeding point is offset from the center of the first radiator 111 by a certain distance, which can be between 2 mm and 5 mm, for example, the offset distance is 2 mm, 3 mm, 4 mm or 5 mm. In this way, the polarization direction of the first radiator 111 can be consistent or close to consistent with the first direction X, and the polarization direction of the first radiator 111 can be perpendicular to the polarization direction of the second radiator 112, thereby improving the isolation between the first radiator 111 and the second radiator 112.

[0094] In an embodiment, the second radiator 112 can be a slot antenna, and the second radiator 112 can have a continuous structure without a slot design. The second radiator 112 is provided with a second feeding point, and the position of the second feeding point affects the polarization direction of the second radiator 112. In the present embodiment, the distance between the second feeding point and the center of the second radiator 112 is between 3 mm and 5 mm. That is, the position of the second feeding point is offset from the center of the second radiator 112 by a certain distance, which can be between 3 mm and 5 mm, for example, the offset distance is 3 mm, 4 mm or 5 mm. In this way, the polarization direction of the second radiator 112 can be consistent or close to consistent with the second direction Y, and the polarization direction of the second radiator 112 can be perpendicular to the polarization direction of the first radiator 111, thereby improving the isolation between the second radiator 112 and the first radiator 111.

[0095] In an embodiment, as previously described, referring to Figure 4 The metal frame 1 includes a top portion 1a, a bottom portion 1b, and two side portions 1c, which enclose a ring shape. The radiator 11 can include a third radiator 113 and a fourth radiator 114. The third radiator 113 is located at the top portion 1a of the metal frame 1, and the fourth radiator 114 is located at the bottom portion 1b of the metal frame 1. The fourth radiator 114 is provided with a slit 114a. In some embodiments, the third radiator 113 and the fourth radiator 114 can also constitute any one or a combination of multiple of the following antennas: a WLAN antenna, a BT antenna, a BLE antenna, a GNSS antenna, a SLE antenna, a cellular TDD antenna, a cellular FDD antenna, etc. In some embodiments, the number of the third radiator 113 and the fourth radiator 114 can be one or more. For example, the third radiator 113 can be provided with two, and any one of the two third radiators 113 can constitute a WLAN antenna and / or a BT antenna. The fourth radiator 114 can constitute a BLE antenna, and the frequency band corresponding to the BLE antenna can be 2400-2480 MHz. Since the two third radiators 113 are located at the same side of the metal frame 1 and adjacent to each other, in order to improve the isolation between the two third radiators 113, the decoupling branch 13 described above can be provided between the two third radiators 113, so that a larger isolation between adjacent antennas can be obtained.

[0096] In addition, the third radiator 113 can excite a third electric field, and the fourth radiator 114 can excite a fourth electric field. The direction of the third electric field is perpendicular to the direction of the fourth electric field. Since the third radiator 113 is provided at the top portion 1a of the metal frame 1, the direction of the third electric field is consistent with the second direction Y. The fourth radiator 114 is provided at the bottom portion 1b of the metal frame 1. In the case where the metal frame 1 is not provided with the slit 114a, the direction of the fourth electric field is consistent with the second direction Y. In the present embodiment, Figure 14 For Figure 4 the electric field distribution diagram of the fourth radiator 114, referring to Figure 14 , the slit 114a is provided at a corresponding position on the fourth radiator 114, for example, the slit 114a is provided at the center position of the fourth radiator 114. The slit 114a can affect the electric field distribution of the fourth radiator 114, so that the direction of the fourth electric field is consistent with the first direction X. Thus, the direction of the fourth electric field can be perpendicular to the direction of the third electric field, so that the isolation between the fourth radiator 114 and the third radiator 113 can be improved.

[0097] Figure 15 For the S parameter diagram of the third radiator 113 and the fourth radiator 114 provided by an embodiment of the present application, referring to Figure 15 ,Figure 15 The curve e in FIG. 13 is the isolation S12 curve between the two third radiators 113, and the curve f is the isolation S23 curve between any one of the third radiators 113 and the fourth radiator 114. In the present application, the two third radiators 113 can be symmetrically distributed on the top 1a of the metal frame 1, and the two third radiators 113 have a decoupling branch 13 therebetween. The two third radiators 113 have the same structure and the same radiation mode, and the isolation curve between any one of the third radiators 113 and the fourth radiator 114 is the same. Therefore, the above S13 curve (the isolation between the first radiator 111 and the second radiator 112) is taken as an example for description in the embodiment. As can be seen from the curve e in FIG. 13, the two third radiators 113 have a high isolation, which can reach close to 23 dB. At the same time, as can be seen from the curve f, the third radiator 113 and the fourth radiator 114 have a high isolation, which can reach 25 dB. Figure 15

[0098] It should be noted that the width of the slot 114a needs to meet certain size requirements to enable the fourth radiator 114 to generate the expected electric field direction. If the size of the slot 114a is too small, it is difficult to achieve the effect of changing the electric field direction of the fourth radiator 114 to be perpendicular to the third electric field direction. If the size of the slot 114a is too large, the structural strength of the metal frame 1 will be reduced. Therefore, in the embodiment, the width of the slot 114a can be between 1.5 mm and 5 mm. For example, the width of the slot 114a can be 1.5 mm, 2 mm, 3 mm, 4 mm, or 5 mm, so that the fourth electric field direction can be perpendicular to the third electric field direction, and the structural strength of the metal frame 1 can be ensured.

[0099] The above merely provides preferred embodiments of the present application but should not be used to limit the present application. Various modifications and changes can be made by those skilled in the art to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall fall within the scope of the present application.​

Claims

1. A head-mounted display device, comprising: The application relates to a metal frame for a radio frequency circuit board. The metal frame comprises: a support; a circuit board connected to the support, the circuit board being provided with a radio frequency circuit; 2. The head-mounted display device of claim 1, wherein, a metal frame connected to the support, the metal frame being wholly or partially provided with a radiation body, the radiation body being spaced apart from the support, and the radiation body being electrically connected to the radio frequency circuit.

3. The head-mounted display device of claim 1 or 2, wherein, The metal frame continuously surrounds the outside of the support, or at least part of the metal frame continuously surrounds the outside of the support.

4. The head-mounted display device of claim 3, wherein, The metal frame is provided with a plurality of slits, and the radiation body comprises a part of the metal frame adjacent to the slits.

5. The head-mounted display device of claim 3 or 4, wherein, The width of the slits is between 1.5 mm and 5 mm.

6. The head-mounted display device of claim 5, wherein, The metal frame comprises a decoupling branch, the decoupling branch being arranged between at least two adjacent radiation bodies, and the two ends of the decoupling branch being spaced apart from the adjacent radiation bodies through the slits, the decoupling branch being electrically connected to the support.

7. The head-mounted display device of any of claims 5, wherein, At least two radiation bodies are located on the same side of the metal frame, and the decoupling branch is arranged between the two adjacent radiation bodies located on the same side of the metal frame.

8. The head-mounted display device of any of claims 1-7, wherein, The distance between the two adjacent radiation bodies located on the same side of the metal frame is between 28 mm and 40 mm, and the length of the decoupling branch is between 24 mm and 34 mm. The metal frame comprises a top, a bottom and two sides, and the top, the bottom and the two sides form a ring shape. The radiation body comprises a first radiation body and a second radiation body, the first radiation body is located on the side, and the second radiation body is located on the bottom.

9. The head-mounted display device of claim 8, wherein, The first radiation body can excite a first electric field, and the second radiation body can excite a second electric field, the direction of the first electric field being perpendicular to the direction of the second electric field.

10. The head-mounted display device of claim 8, wherein, The first radiation body is provided with a first feeding point for electrical connection with the radio frequency circuit, and the distance between the first feeding point and the center of the first radiation body is between 2 mm and 5 mm.

11. The head-mounted display device of any of claims 1-7, wherein, The second radiation body is provided with a second feeding point, and the distance between the second feeding point and the center of the second radiation body is between 3 mm and 5 mm. The metal frame comprises a top, a bottom and two sides, and the top, the bottom and the two sides form a ring shape. The radiation body comprises a third radiation body and a fourth radiation body, the third radiation body is located on the top, and the fourth radiation body is located on the bottom, and the fourth radiation body is provided with a slit.

12. The head-mounted display device of claim 11, wherein, The third radiation body can excite a third electric field, and the fourth radiation body can excite a fourth electric field, the direction of the third electric field being perpendicular to the direction of the fourth electric field.

13. The head-mounted display device of claim 8 or 11, wherein, The width of the slit is between 1.5 mm and 5 mm.

14. The head-mounted display device of any of claims 1-13, wherein, The electromagnetic signal corresponding to the frequency band received and transmitted by the second radiation body or the fourth radiation body is between 2400 MHz and 2480 MHz.

15. The head-mounted display device of claim 14, wherein, The material of the support is metal.

16. The head-mounted display device of any of claims 1-15, wherein, The metal frame and the support are integrally formed.

17. The head-mounted display device of claim 16, wherein, The radiation body and the radio frequency circuit are electrically connected through a metal piece. The metal piece comprises a spring or a screw.

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