Optical module, tunable optical system and head-mounted display device
By combining piezoelectric actuators and pre-tensioning components, automatic focusing and focus stabilization during drops are achieved in the head-mounted display device, solving the focusing problem for users with different vision needs and improving the user experience and reliability of the device.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- MATRIXED REALITY TECH CO LTD
- Filing Date
- 2025-05-06
- Publication Date
- 2026-06-26
AI Technical Summary
Existing head-mounted display devices are difficult to meet the focusing needs of users with different vision requirements, especially specific groups such as those with myopia, and the focal length is prone to change when accidentally dropped.
The piezoelectric actuator drives the columnar structure, and through the cooperation of the pre-tightening component and the output component, it realizes the precise movement of the image source component, adjusts the distance between the image source component and the optical component, and achieves automatic focusing by combining sensors and control logic, and maintains a stable focal length during drop.
It achieves automatic focusing function for head-mounted displays, adapts to different vision needs, improves user experience, and maintains the focal length during drops, thus improving the reliability and safety of the device.
Smart Images
Figure CN224417117U_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to the field of head-mounted display technology, and in particular to an optical module, a focusable optical system, and a head-mounted display device. Background Technology
[0002] Currently, VR (Virtual Reality), AR (Augmented Reality), and MR (Mixed Reality) are attracting more and more users. Users need to wear head-mounted displays to experience these effects. Improving the user experience and meeting the needs of specific groups, such as those with myopia, are important directions for the development of head-mounted display devices. Utility Model Content
[0003] This disclosure provides an optical module, an adjustable focus optical system, and a head-mounted display device.
[0004] To achieve the above objectives, this disclosure provides the following technical solution:
[0005] In a first aspect, embodiments of this disclosure provide an optical module, including: a bracket, an output component, an image source component, a piezoelectric actuator, a columnar structure, and a pretensioner; the output component is movable relative to the bracket; the image source component is at least partially disposed on the output component; the piezoelectric actuator provides power for the movement of the output component; the columnar structure is in contact with the piezoelectric actuator, and the output component is capable of linearly moving along the columnar structure to drive the image source component to move; the pretensioner is disposed on the output component, and under the action of the pretensioner, the columnar structure generates a pretensioning force with at least one of the piezoelectric actuator and the output component; when the piezoelectric actuator does not apply a force, the output component and the columnar structure remain relatively stationary under the action of the pretensioning force; when the piezoelectric actuator applies a force, the output component can move along the columnar structure to drive the image source component to move.
[0006] Secondly, embodiments of this disclosure provide an adjustable-focus optical system, including an optical component and the aforementioned optical module. The optical component and the optical module are disposed on the same side of a support. The output component of the optical module drives the image source component to move, thereby adjusting the distance between the image source component and the optical component. The light emitted by the image source component can be projected onto the optical component, and the optical component can adjust the optical path of the light emitted by the image source component.
[0007] Thirdly, embodiments of this disclosure provide a head-mounted display device, including: a frame and an adjustable optical system, the adjustable optical system being disposed on the frame.
[0008] The technical solutions of this disclosure will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description
[0009] The accompanying drawings, which form part of this specification, illustrate embodiments of this disclosure and, together with the description, serve to explain the principles of this disclosure.
[0010] This disclosure will become clearer with reference to the accompanying drawings and the following detailed description, wherein:
[0011] Figure 1 This diagram illustrates the structure of the optical module in a first type of head-mounted display device according to an embodiment of the present disclosure.
[0012] Figure 2 A schematic diagram of the structure of an adjustable-focus optical system for a first type of head-mounted display device provided in this disclosure embodiment is shown.
[0013] Figure 3 This diagram illustrates a first possible assembly structure of the output component, columnar structure, and pretensioner in the optical module of the head-mounted display device provided in this embodiment.
[0014] Figure 4 This diagram illustrates a second possible assembly structure of the output component, columnar structure, and pretensioner in the optical module of the head-mounted display device provided in an embodiment of the present disclosure.
[0015] Figure 5 This diagram illustrates a third possible assembly structure of the output component, columnar structure, and pretensioner in the optical module of the head-mounted display device provided in this embodiment.
[0016] Figure 6 A waveform diagram of the driving voltage of the piezoelectric driver of the head-mounted display device provided in the embodiments of this disclosure is shown, along with a comparison diagram of the output component moving upward along the columnar structure.
[0017] Figure 7 A waveform diagram of the driving voltage of the piezoelectric driver of the head-mounted display device provided in the embodiments of this disclosure is shown, along with a comparison diagram of the output component moving downward along the columnar structure.
[0018] Figure 8 This diagram illustrates the structure of the optical module in a second type of head-mounted display device provided in this embodiment.
[0019] Figure 9 A schematic diagram of the adjustable-focus optical system of a second head-mounted display device provided in an embodiment of this disclosure is shown.
[0020] Figure 10 A partial structural schematic diagram of the adjustable-focus optical system of the third head-mounted display device provided in this disclosure embodiment is shown;
[0021] Figure 11 This diagram illustrates the structure of the optical module of the fourth type of head-mounted display device provided in this embodiment.
[0022] Figure 12 A partial structural schematic diagram of the adjustable-focus optical system of the fifth head-mounted display device provided in this disclosure embodiment is shown;
[0023] Figure 13 This diagram illustrates the structure of the optical system of the sixth head-mounted display device provided in this embodiment.
[0024] Figure 14 A schematic diagram of an adjustable focus optical system provided in an embodiment of this disclosure is shown.
[0025] In the diagram, 1 is the bracket; 11 is the crossbeam; 111 is the mounting hole; 12 is the first housing; 121 is the clearance hole; 122 is the guide post; 13 is the base; 14 is the second housing; 2 is the output assembly; 21 is the mounting assembly; 211 is the mating part; 212 is the limiting body; 22 is the sliding assembly; 23 is the limiting part; 24 is the notch; 25 is the structure; 3 is the piezoelectric actuator; 4 is the columnar structure; 5 is the preload; 6 is the image source assembly; 61 is the display component; 62 is the lens; 7 is the PCB circuit board; 8 is the ranging component; 9 is the optical assembly; 91 is the beam splitter; 92 is the curved lens; 10 is the ranging mating part; y is the eye; z is the threaded part.
[0026] It should be noted that these figures and descriptions are not intended to limit the scope of the present invention in any way, but rather to illustrate the concepts of the disclosure to those skilled in the art by referring to specific embodiments. Detailed Implementation
[0027] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings. The following embodiments are used to illustrate this disclosure, but are not intended to limit the scope of this disclosure.
[0028] In the description of this disclosure, it should be noted that the terms "upper", "lower", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this disclosure and simplifying the description, and are not intended to indicate or imply that the device referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this disclosure.
[0029] In the description of this disclosure, it should be noted that, unless otherwise expressly specified and limited, the terms "installation" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this disclosure based on the specific circumstances.
[0030] Exemplary Overview
[0031] Head-mounted display devices, also known as head-mounted displays (HMDs) or head-mounted displays, can be used to achieve augmented reality (AR), virtual reality (VR), and mixed reality (MR) effects. They can take the form of glasses, helmets, etc. In a head-mounted display device, the image source component 6 provides image information, and the optical component 9 adjusts the light so that it is projected onto the user's eyes, allowing the user to view the image information. Figure 14 The diagram shows the optical system of a head-mounted display device. The image source component 6 is used to emit light that can form an image, and the optical component 9 is used to adjust the optical path of the light emitted by the image source component 6 and project the light towards the first side of the image source component 6 so that when the glasses are worn on the user's head, the light can be projected into the user's eye y, thereby forming an image in the user's eye y.
[0032] Exemplary Structure
[0033] Figure 1 This diagram illustrates the structure of an optical module in a first type of head-mounted display device provided in this disclosure. Figure 2 This diagram illustrates the structure of a focusable optical system for a first type of head-mounted display device according to an embodiment of the present disclosure. In some optional embodiments of the present disclosure, the optical module may include: a support 1, a driving component, and an image source component 6, the image source component 6 being movably connected to the support 1. The driving component provides the driving force for moving the image source component 6, enabling the image source component 6 to move relative to the support 1.
[0034] In some possible implementations, such as Figure 1 and Figure 2 As shown, the optical module may include an output component 2, which is movable relative to the support 1. An image source component 6 is at least partially disposed on the output component 2, and movement of the output component 2 can drive movement of the image source component 6. The driving component may include a piezoelectric actuator 3, which provides power for the movement of the output component 2.
[0035] Understandably, various types of drive components exist on the market, such as SMA shape memory alloy motors, VCM voice coil motors, and stepper motors. Considering factors such as optical stability, size, weight, and drive voltage, experimental verification has shown that the piezoelectric driver 3 is more suitable as a driver for head-mounted displays. The piezoelectric driver 3 has excellent motion resolution, achieving an accuracy level of 10nm to 100nm, while ordinary stepper motors can only achieve an accuracy of 1 to 10μm. Therefore, the piezoelectric driver 3 is more suitable for compact head-mounted display devices.
[0036] In some exemplary embodiments of this disclosure, such as Figure 1 and Figure 2 As shown, the optical module may include a columnar structure 4. One end of the piezoelectric actuator 3 is fixed, and the other end of the piezoelectric actuator 3 is connected to the columnar structure 4. The piezoelectric actuator 3 drives the columnar structure 4 to reciprocate along the length of the columnar structure 4, thereby driving the output component 2 located on the columnar structure 4 to move along the columnar structure 4, thereby driving the image source component 6 to move.
[0037] In some optional examples, the fixed end of the piezoelectric actuator 3 described above includes, but is not limited to, the following situations: The piezoelectric actuator 3 can be directly connected to the bracket 1. For example, the piezoelectric actuator 3 can be glued to the bracket 1. The piezoelectric actuator 3 can also be indirectly connected to the bracket 1. For example, the piezoelectric actuator 3 can be fixedly connected to the bracket 1 via the base 13. Figure 1 As shown, the bracket 1 can be partially structured as a structure in a product that uses an optical module. For example, the bracket 1 may include the beam 11 of a head-mounted display device, and the piezoelectric actuator 3 may also be connected to the beam 11.
[0038] In some optional embodiments, the piezoelectric actuator 3 utilizes the inverse piezoelectric effect. By applying a voltage across its terminals, its length changes linearly with the magnitude of the voltage, and the amount of length change is directly proportional to the magnitude of the voltage, enabling real-time response. Under external voltage excitation, the piezoelectric actuator 3 can drive the columnar structure 4 to displace relative to the support 1.
[0039] In some alternative embodiments, such as Figure 1 and Figure 2 As shown, the optical module may include a pre-tensioning member 5, which may be disposed on the output component 2. Under the action of the pre-tensioning member 5, the columnar structure 4 generates a pre-tensioning force with at least one of the piezoelectric actuator 3 and the output component 2. When the piezoelectric actuator 3 is not applying a force, the output component 2 and the columnar structure 4 can remain relatively stationary under the action of the pre-tensioning force. When the piezoelectric actuator 3 applies a force, the output component 2 can move along the columnar structure 4, driving the image source component 6 to move.
[0040] In some optional embodiments, the weight of the output component 2 and the image source component 6 disposed thereon can be approximately 2g to 5g, the coefficient of friction between the columnar structure 4 and one of the piezoelectric actuator 3 and the output component 2 is approximately 0.1 to 0.3, and the preload applied by the preload member 5 is 30gf to 500gf. The above parameters are set to ensure that, even when the acceleration of the output component 2 upon drop is 10 times the acceleration due to gravity, the friction between the columnar structure 4 and the piezoelectric actuator 3 or the output component 2 is sufficiently large to keep the output component 2 in a fixed position and maintain the focal length of the head-mounted display device.
[0041] Taking a head-mounted display device worn at a height 1.5m above the ground as an example, at the instant the head-mounted display device accidentally falls and stops upon contact with the ground, the acceleration of the image source component 6 is approximately 10 times the acceleration due to gravity. Therefore, the image source component 6 needs to be subjected to a frictional force of 20gf to 50gf to maintain its position, that is, its position relative to the bracket 1 remains unchanged. Thus, when the pre-tightening force of the pre-tightening member 5 is in the range of 30gf to 500gf, it is sufficient to ensure that the output component 2 or the piezoelectric actuator 3 mounted on the output component 2 can be subjected to sufficient frictional force to maintain its position when the head-mounted display device is accidentally dropped. The focal length of the head-mounted display device will not change due to the accidental drop of the device or other reasons.
[0042] In some optional embodiments, when the piezoelectric actuator 3 applies a force to the columnar structure 4, and the moving speed of the columnar structure 4 is less than a set speed, the columnar structure 4 can drive the output component 2 to move synchronously under the action of the preload. When the piezoelectric actuator 3 applies a force to the columnar structure 4, and the moving speed of the columnar structure 4 is greater than or equal to the set speed, the output component 2 is fixed relative to the support 1, and the columnar structure 4 can move relative to the output component 2.
[0043] Figure 3 This diagram illustrates a first possible arrangement of the output component 2, the columnar structure 4, and the pretensioner 5 in the optical module of the head-mounted display device provided in this embodiment. Figure 4 This diagram illustrates a second type of mating structure of the output component 2, the columnar structure 4, and the pretensioner 5 in the optical module of the head-mounted display device provided in this embodiment. Figure 5 This diagram illustrates a third possible arrangement of the output component 2, the columnar structure 4, and the pretensioner 5 in the optical module of the head-mounted display device provided in this embodiment. In some optional embodiments, the pretensioner 5 can be a spring sheet connected to the output component 2. The columnar structure 4 is located between the spring sheet and the output component, with the spring sheet elastically abutting against the columnar structure 4. Under the action of the spring sheet, a pretensioning force exists between the output component 2 and the columnar structure 4.
[0044] In some alternative embodiments, such as Figures 3 to 5As shown, at least one end of the output component 2 and the spring piece are fastened together by a threaded part z. Tightening the threaded part z adjusts the preload. A threaded groove can be provided on the output component 2, and the stud of the threaded part z is threaded into the threaded groove. The cap of the threaded part z is pressed against the spring piece. By tightening the threaded part, the clamping force between the cap and the spring piece can be adjusted, thereby adjusting the preload between the columnar structure 4 and the output component 2.
[0045] Output component 2, spring, and threaded component z can be configured in several different ways. In the first configuration, such as... Figure 3 As shown, both ends of the spring are connected to the output assembly via threaded parts z, and the columnar structure 4 is located between the two threaded parts z. In the second configuration, as... Figure 4 As shown, the output component 2 has a limiting part 23. One end of the spring piece is connected to the output component 2 via a threaded member z, and the other end of the spring piece is limited within the limiting part 23 of the output component 2. The columnar structure 4 is located between the threaded member z and the limiting part 23. The limiting part 23 may include a slot provided on the output component 2, and one end of the spring piece can be inserted and fixed in the slot. In the third setting method, as shown... Figure 5 As shown, one end of the spring is connected to the output assembly via a threaded component z, and the other end of the spring is a free end. The columnar structure 4 is located between the threaded component z and the free end.
[0046] In some alternative embodiments, such as Figures 3 to 5 As shown, the edge of the output component 2 can be provided with a notch 24, through which the columnar structure 4 can pass. Part of the columnar structure 24 protrudes from the notch 24 to contact the spring piece. The notch 24 serves to limit the columnar structure 24, restricting its movement relative to the output component 2 only in the thickness direction (or the direction of movement) of the output component 2.
[0047] In some alternative embodiments, the piezoelectric actuator 3 can be an inertial (also known as a smooth impact drive) piezoelectric actuator, which is more compact in structure, better suited to vertical up-and-down motion applications, and has a simpler structure.
[0048] Figure 6 The diagram shows a waveform of the driving voltage of the piezoelectric actuator of the head-mounted display device provided in this embodiment of the present disclosure, compared with a diagram showing the output component moving upward along the columnar structure. In the diagram, a, b, c, d, and e represent time points in the operation of the piezoelectric actuator. When a slowly increasing voltage (e.g., ...) is applied to the piezoelectric actuator 3... Figure 6 (At time node ab, corresponding to the state), the piezoelectric actuator 3 will drive the columnar structure 4 to move slowly (e.g., Figure 6The state corresponding to time node ab in the middle of the time frame should be noted. It should be noted that this slow movement is only relative, and the movement generally needs to be completed within 0.01ms. At this time, due to the presence of preload, the friction between the output component 2 and the columnar structure 4 can cause the output component 2 to drive the image source component 6 to move upward synchronously. Then, a rapid voltage change is applied (such as...). Figure 6 At time node bc (corresponding to the state), columnar structure 4 will retract instantly, but output component 2 and image source component 6 remain in their original positions. Columnar structure 4 moves downwards relative to output component 2 (e.g., ...). Figure 6 (The state corresponding to time node bc). The above two actions can be considered as a cycle, in which the image source component 6 moves upward by a step, typically within the range of 1 to 100 nm. The high-frequency piezoelectric input piezoelectric actuator 3 causes the piezoelectric actuator 3 to drive the columnar structure 4 to vibrate at high frequency, while simultaneously driving the image source component 6 to move upward continuously. Thus, inputting the above-mentioned "slow rise and fast fall" voltage to the piezoelectric actuator 3 can drive the output component 2 to move upward stably.
[0049] Figure 7 The diagram shows a waveform of the driving voltage of the piezoelectric actuator of the head-mounted display device provided in this embodiment of the present disclosure, compared with a diagram showing the output component moving downward along the columnar structure. In the diagram, a, b, c, d, and e represent time points in the operation of the piezoelectric actuator. When a rapidly increasing voltage (e.g., when the piezoelectric actuator 3 is provided with a voltage that increases rapidly) is shown... Figure 7 (At time node ab, corresponding to the state), the piezoelectric actuator 3 will cause the columnar structure 4 to rise rapidly (e.g., Figure 7 The state corresponding to time node ab is such that, due to inertia, output component 2 and image source component 6 remain in their original positions, and then a slowly decreasing voltage change is applied (e.g. Figure 7 At time node bc (corresponding to state), the columnar structure 4 will slowly retract, and the friction between the output component 2 and the columnar structure 4 will cause the output component 2 to drive the image source component 6 to move downward synchronously. The above two actions can be considered as a cycle, in which the image source component 6 moves downward by one step, typically in the range of 1 to 100 nm. The high-frequency piezoelectric input piezoelectric actuator 3 can cause the piezoelectric actuator 3 to drive the columnar structure 4 to vibrate at high frequency, while simultaneously driving the image source component 6 to move downward continuously. In this way, the "fast rise and slow fall" voltage input to the piezoelectric actuator 3 can drive the output component 2 to move downward stably.
[0050] In some alternative embodiments, such as Figure 6 and Figure 7 As shown, the input voltage of the piezoelectric actuator 3 can be a triangular pulse. Under a single pulse, the movement step of the output component 2 is 1 to 100 nm. The frequency of the voltage pulse of the piezoelectric actuator 3 is between 10 kHz and 10 MHz, which allows the output component 2 to move within a speed range of 1 mm / s to 10 mm / s.
[0051] In some optional embodiments, the piezoelectric actuator 3 (or piezoelectric motor) weighs less than or equal to 0.2g, generates a driving force of 3gf to 6gf, achieves a movement speed of 1 to 10mm / s, and has a driving voltage of less than or equal to 3.3V. The piezoelectric actuator 3 is lightweight, small in size, and occupies little space, facilitating the arrangement of other modules within the optical module and reducing costs. The driving voltage of less than or equal to 3.3V provides sufficient energy for the piezoelectric actuator 3 to generate a large driving force, enough to smoothly drive the output component 2.
[0052] In some optional examples, the columnar structure 4 exhibits good wear resistance. During the long-term movement of the output component 2 along the columnar structure 4, the columnar structure 4 will not experience severe wear, thus extending product lifespan and improving product quality. The columnar structure 4 has low density and is lightweight, which is beneficial for the lightweight design of head-mounted display devices. The columnar structure 4 has high strength and is not easily bent or deformed, ensuring that the output component 2 moves in a straight line and is not easily tilted, which helps the head-mounted display device maintain high image quality. The columnar structure 4 can be a carbon rod or can be replaced with other materials that meet the above performance requirements.
[0053] In some optional embodiments, the peripheral surface of the columnar structure 4 can be a smoothly transitioned arc surface, and no sharp edges may be provided on the peripheral surface. This reduces the friction and vibration of the relative movement between the output component 2 and the columnar structure 4, and also reduces wear, thereby improving product reliability. The columnar structure 4 can be a cylinder, which can be inserted into a through hole disposed between the output component 2 or between the output component 2 and the preload member 5. This shaft and hole mating structure provides high positioning accuracy and coaxiality, ensuring accurate alignment between the components.
[0054] In some alternative examples, the preload 5 and the output assembly 2 can be two separate components. For example, the preload 5 can be connected to the output assembly 2 via fasteners, snap-fit, or adhesive. The preload 5 can form a through groove with the output assembly 2, through which the columnar structure 4 passes. Alternatively, the preload 5 can be press-fitted between the columnar structure 4 and the output assembly 2. Or, the preload 5 itself has a through groove, through which the columnar structure 4 passes, and one side of the preload 5 is connected to the image source assembly 6. The preload 5 can also be part of the output assembly 2, i.e., the preload 5 and the output assembly 2 are an integral structure.
[0055] Figure 8 This diagram illustrates the structure of an optical module in a second type of head-mounted display device provided in this embodiment. Figure 9 A schematic diagram of the adjustable-focus optical system of a second head-mounted display device provided in an embodiment of this disclosure is shown. Figure 10A partial structural schematic diagram of the adjustable-focus optical system of a third head-mounted display device provided in this disclosure embodiment is shown. The columnar structure 4 of the optical module can be connected to the bracket 1, and the output component 2 is connected to the piezoelectric actuator 3. Under the action of voltage, the piezoelectric actuator 3 can move linearly along the columnar structure 4 and drive the output component 2 to move, thereby driving the image source component 6 to move.
[0056] In some optional embodiments, the piezoelectric actuator 3 is a resonant (or inchworm-type) piezoelectric actuator 3. The resonant piezoelectric actuator 3 utilizes the inverse piezoelectric effect of the piezoelectric material, generating mechanical vibration through deformation of the piezoelectric material under the influence of an electric field. When the resonant piezoelectric actuator 3 is installed on the output component 2, it can move along the columnar structure 4 on the support 1, thereby driving the output component 2 to move. The resonant piezoelectric actuator 3 can provide a large torque output at low speeds, smoothly driving or propelling the output component 2, on which the image source component 6 is mounted, to move.
[0057] In some alternative embodiments, the resonant piezoelectric actuator 3 can be a single-point drive or a multi-point drive, which can effectively drive the output component 2 to move up and down relative to the columnar structure 4.
[0058] In some optional embodiments, the resonant piezoelectric actuator 3 can achieve a driving force of over 10 gf, a movement speed of >10 mm / s, and a driving voltage of <3.3 V. This resonant piezoelectric actuator 3 has a low driving voltage, low power supply requirements, high safety, can provide a large torque output, and has a fast response speed, enabling it to smoothly drive the output component 2 to move.
[0059] In some alternative embodiments, such as Figure 8 and Figure 9 As shown, the output component 2 may include a sliding component 22, which is connected to the image source component 6. After a voltage is applied to the piezoelectric actuator 3, the driving end of the piezoelectric actuator 3 generates mechanical vibration, which can actively move along the columnar structure 4 to drive the sliding component 22 to move, and then drive the image source component 6 to move.
[0060] In an optional example, such as Figure 8 As shown, the output component 2 may include a sliding component 22 and a mounting component 21. The sliding component 22 is connected to the image source component 6, and the mounting component 21 is slidably connected to the columnar structure 4. The sliding component 22 and the mounting component 21 can be connected by fasteners, snap-fit structures, or adhesive structures. Optionally, the sliding component 22 and the mounting component 21 can be integrally formed. The preload 4 and the piezoelectric actuator 3 can both be disposed on the mounting component 21. Under the elastic force of the preload 4, the driving end of the piezoelectric actuator 3 abuts against the columnar structure 4, and the piezoelectric actuator 3 can move along the columnar structure 4 to drive the sliding component 22 to move.
[0061] In some alternative embodiments, such as Figure 8 As shown, the mounting assembly 21 may include two mating parts 211 and a limiting body 212 connecting the two mating parts 211. The limiting body 212 is connected to the sliding assembly 22. A columnar structure 4 is disposed through the two mating parts 211. A piezoelectric actuator 3 is disposed between the two limiting bodies 212, and the columnar structure 4 is located between the limiting body 212 and the piezoelectric actuator 3. The preload member 5 may be an elastic member, with its two ends supported on the two mating parts 211, its middle part bulging outward and elastically abutting against the piezoelectric actuator 3, so that the driving end of the piezoelectric actuator 3 remains in contact with and abuts against the columnar structure 4. Optionally, the mounting assembly 21 may also have two surfaces disposed opposite to each other along the columnar structure 4, and the piezoelectric actuator 3 may be disposed between the two oppositely disposed surfaces.
[0062] Under the preload, the friction between the columnar structure 4 and the output component 2 is no less than the weight of the output component 2. Therefore, when the piezoelectric actuator 3 is not energized, the output component 2 and the image source component 6 are fixed in position and will not slide down the columnar structure 4.
[0063] In some possible embodiments, such as Figure 1 and Figure 9 As shown, the image source component 6 may include at least one of a display component 61 and a lens 62.
[0064] In some possible embodiments, source component 6 may include display component 61 and lens 62, such as Figure 1 As shown. The image source component 6 is integrally mounted on the output component 2, with the display component 61 and lens 62 of the image source component 6 located on both sides of the output component 2 along the direction of movement. The display component 61 and lens 62 can both be mounted on the output component 2. For example, the display component 61 and lens 62 can be mounted on both sides of the output component 2 along the thickness direction. A clearance opening can be provided on the output component 2, allowing light emitted from the display component 61 to pass through the clearance opening and enter the lens 62.
[0065] Figure 11 This diagram illustrates the structure of an optical module for a fourth type of head-mounted display device according to an embodiment of this disclosure. The image source component 6 may include a display component 61 and a lens 62. The image source component 6 can be entirely mounted on the output component 2. The display component 61 and the lens 63 of the image source component 6 can be located on the same side of the output component 2, and the display component 61 is attached to the output component 2. The output component 2 is connected to a structure 25. The lens 62 can be mounted on the structure 25, with a gap between the lens 62 and the output component 2. The display component 61 is located on the side of the output component facing the structure 25.
[0066] In some possible embodiments, the image source component 6 may include a display component 61 and a lens 62, with the display component 62 disposed on the output component 2 and the lens 63 disposed on the bracket 1. Figure 12 This diagram illustrates a partial structural schematic of a focusable optical system for a fifth type of head-mounted display device according to an embodiment of the present disclosure. The display component 61 can be disposed at the bottom of the output assembly 2, while the lens 62 can be disposed on the support 1. The support 1 may include a first housing 12 and a second housing 14. The first housing 12 can be connected to the crossbeam 11 of the head-mounted display device. The first housing 12 and the second housing 14 are connected, forming an inner cavity between them. The columnar structure 4 and the output assembly 2 can be disposed within the inner cavity. The display component 61 can be disposed on the output assembly 2, while the lens 62 of the image source assembly 6 can be disposed on the second housing 14 of the support 1. The optical component 9 of the optical system can be disposed on the second housing 14, with the lens 62 located between the display component 61 and the optical component 9.
[0067] In some optional embodiments, a display component 61 and a lens 62 may be respectively disposed on both sides of the output component 2 along the thickness direction, and the display component 61, the lens 62, and the output component are fixedly connected to form a single unit. Movement of the output component can simultaneously move the display component 61 and the lens 62. The display component 61 and the lens 62 can be connected and assembled with the output component 2 by means of fasteners, snap-fit connections, or adhesives.
[0068] In some alternative embodiments, the display component 61 can be used to emit light for displaying an image. The display component 61 may include, but is not limited to, an organic light-emitting diode (OLED) image source, a liquid crystal image source, a liquid crystal on silicon (LCOS) image source, a microelectromechanical system (MEMS) image source, a digital micromirror device (DMD), etc. For example, the display component 61 can be an OLED display screen.
[0069] Optionally, lens 62 can be an aspherical lens, which can correct field curvature, pupil swim, and chromatic aberration to ensure the imaging quality of the optical system.
[0070] In some optional examples, such as Figure 1 and Figure 3As shown, the optical module may further include a guide post 122, which can be fixedly connected to the bracket 1 and can be parallel to the columnar structure 4. A guide hole can be provided on the output component 2, and the guide post 122 can pass through the guide hole on the output component 2. The guide post 122 and the columnar structure 4 cooperate to restrict the movement direction of the image source component 6, limiting the image source component 6 to move only along the length direction of the columnar structure 4. When the optical module is applied to a head-mounted display device, the guide post 122 and the columnar structure 4 cooperate to restrict the image source component 6 to move only along the height direction of the head-mounted display device. The two ends of the output component 2 along its length are respectively guided and engaged with the guide post 122 and the columnar structure 4, so that the output component 2 can smoothly rise and fall under the action of the piezoelectric actuator 3, and the two ends are less prone to tilting. The guide hole can be a round hole or a notch. The contact surface between the guide post 122 and the guide hole is smooth, which reduces friction.
[0071] It should be noted that the piezoelectric actuator 3 can be disposed at different locations on the bracket 1. The bracket 1 may consist only of the first housing 12, and the piezoelectric actuator 3 may be disposed on the first housing 12. Alternatively, the bracket 1 may include a first housing 12 and a second housing 14, and the first housing 12 may be connected to the crossbeam 11 of the head-mounted display device. The piezoelectric actuator 3 may be disposed on any one of the crossbeam 11, the first housing 12, and the second housing 14. Figure 13 This diagram illustrates the structure of the optical system of a sixth head-mounted display device according to an embodiment of the present disclosure. A first housing 12 and a second housing 14 are connected, forming an inner cavity between them. The columnar structure 4 and the output component 2 can be disposed within this inner cavity. The piezoelectric actuator 3 can be disposed on the second housing 14. Similarly, the guide post 122 can also be disposed on either the crossbeam 11, the first housing 12, or the second housing 14.
[0072] It should be noted that the height direction of the head-mounted display device mentioned in the text can be understood as... Figure 1 and Figure 2 The direction indicated by the middle arrow H. Figure 1 and Figure 2 The arrow L in the diagram indicates the length direction of the head-mounted display device.
[0073] Some exemplary embodiments of this disclosure also provide a focusable optical system, such as Figure 2 and Figure 8As shown, the adjustable-focus optical system includes an optical component 9 and the aforementioned optical module. The optical component 9 and the optical module are mounted on a support 1. The output component 2 of the optical module moves the image source component 6 away from or closer to the optical component 9 to adjust the distance between the image source component 6 and the optical component 9, i.e., to adjust the focal length. The light emitted by the image source component 6 can be projected onto the optical component 9, and the optical component 9 can adjust the optical path of the light emitted by the image source component 6.
[0074] Optical components 9 and optical modules are arranged sequentially along the length of the columnar structure 4, with the optical module positioned between optical components 9 and the support 1. Optical components 9 and the support 1 are fixed in relative position and do not move relative to the support 1; only the image source component 6 can move along the columnar structure 4 under the action of the piezoelectric actuator 3. The image source component 6 emits light capable of forming an image, and the optical component 9 adjusts the optical path of the light emitted by the image source component 6, projecting the light towards the first side of the image source component 6 so that when the glasses are worn on the user's head, the light can be projected into the user's eyes, thereby forming an image in the user's eyes.
[0075] Figure 14 A schematic diagram of an adjustable-focus optical system provided in this disclosure embodiment is shown. The optical component 9 may include a beam splitter 91 and a reflector 92. Light emitted from the image source component 6 can be incident on the beam splitter 91. The beam splitter 91 reflects at least a portion of the light emitted from the image source component 6, projecting the light into a second direction onto the reflector 92. The reflector 92 reflects the light projected by the beam splitter 91, projecting the light into a first direction. The light can pass through the beam splitter 91. Therefore, when a user wears glasses, the light emitted from the image source component 6 can be projected into the user's eyes, thereby forming a virtual image in the user's field of vision. By adjusting the lifting and lowering movement of the image source component 6, moving it closer to or further away from the beam splitter 91, the focus of the head-mounted display device can be adjusted.
[0076] In addition to some exemplary embodiments of this disclosure, a head-mounted display device is also provided, comprising: a frame and the aforementioned adjustable-focus optical system, wherein the adjustable-focus optical system is disposed in the frame. By incorporating the adjustable-focus optical system within the head-mounted display device, the image source component 6 can be automatically controlled to move and focus by supplying or de-energizing the piezoelectric actuator 3, making operation more convenient and meeting the user experience needs of users with different visual conditions such as myopia and hyperopia.
[0077] In some alternative embodiments, the adjustable-focus optical system can be housed within the head-mounted display device, allowing for focus adjustment via circuit control. This eliminates the need for knob holes on the surface of the head-mounted display device, resulting in a more integrated and aesthetically pleasing appearance. The absence of knob holes also prevents a reduction in the structural strength of the head-mounted display device and enhances its waterproof and dustproof performance, thereby improving product quality.
[0078] In some optional embodiments, the frame of the head-mounted display device may include a lens frame and temples connecting the lens frame, with a crossbeam 11 disposed within the lens frame and extending along the width direction of the lens frame. The head-mounted display device may include two adjustable optical systems, which may be respectively connected to the crossbeam 11. The support 1 for the adjustable optical system may be a long beam, which can be connected to the frame by any of the following methods: fastener fixing, snap-fit fixing, or adhesive fixing, such as to the crossbeam 11 connecting the frame.
[0079] In some alternative embodiments, the driver can be located inside the head-mounted display device, eliminating the need for knob holes on the surface of the device. This results in a more seamless and aesthetically pleasing appearance. The absence of knob holes also prevents a reduction in the structural strength of the head-mounted display device and enhances its waterproof and dustproof performance, thereby improving product quality.
[0080] In some optional embodiments, the head-mounted display device may further include a ranging component 8 and a ranging mating component 10. The ranging component 8 is disposed on the bracket 1, and the ranging mating component 10 is disposed on the output component 2. The ranging component 8 is used to detect the distance between itself and the ranging mating component 10. The ranging component 8 can be a TMR sensor, a Hall sensor, etc. A PCB circuit board 7 can be disposed on the crossbeam 11, and the ranging component 8 is electrically connected to the PCB circuit board 7.
[0081] In some optional embodiments, to reduce the distance between the ranging component 8 and the ranging mating component 10 and improve ranging accuracy, the head-mounted display device can have a clearance hole 121 on the bracket 1, and a mounting hole 111 on the side of the frame beam 11 near the bracket 1. The ranging component 8 can be installed in the mounting hole 111, and the ranging mating component 10 is connected to the output component 2. The ranging mating component 10 can pass through the clearance hole 121 and extend into the mounting hole 111, thereby reducing the distance between the ranging component 8 and the ranging mating component 10 and improving ranging accuracy. Through this structural design, the minimum distance between the ranging component 8 and the ranging mating component 10 can be controlled between 0.1mm and 1mm.
[0082] In some optional embodiments, the head-mounted display device can employ a piezoelectric actuator 3 and a ranging component 8 to achieve closed-loop control of the focusing degree. Since the assembly positions of the ranging component 8 and the ranging mating part 10 vary between each head-mounted display device, the output voltage measured by the ranging component 8 can be calibrated against the focusing degree. The voltage output by the ranging component 8 exhibits good linearity with the distance between the ranging component 8 and the ranging mating part 10, and the distance deviation between the ranging component 8 and the ranging mating part 10 also has a good linear relationship with the focusing degree. Therefore, it can be considered that the output voltage of the ranging component 8 and the focusing degree are essentially linear. Based on the calibration results, the output component is moved to a specific position by the piezoelectric actuator 3, which also changes the relative position between the ranging components 8. The output voltage of the ranging component 8 is then tested again. If there is a deviation, the position is fine-tuned again, thereby achieving closed-loop control of the focusing degree.
[0083] The head-mounted display device provided in this embodiment of the present disclosure, through an adjustable focusing optical system, and in conjunction with sensors and control logic, enables users to quantitatively set the diopter, and the head-mounted display device automatically adjusts to the corresponding diopter. This avoids the problem of manual focusing, where the diopter cannot be quantitatively set and users can only set the diopter through actual optical perception.
[0084] The above description has been provided for illustrative and descriptive purposes. The above embodiments are merely preferred embodiments of this application, and the technical features described in each of the above embodiments can be used individually. Features of the different embodiments described above can be freely combined without structural contradictions or logical conflicts, and the resulting technical solutions, whether or not explicitly listed in the specification, should be included within the scope of protection of this disclosure. Furthermore, the above description is not intended to limit the embodiments of this disclosure to the forms disclosed herein. Although several exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations therein.
Claims
1. An optical module, comprising: support; An output component, the output component being movable relative to the support; Image source component, which is at least partially disposed in the output component; A piezoelectric actuator for providing power for the movement of an output component; A columnar structure is in contact with the piezoelectric actuator, and the output component can move linearly along the columnar structure to drive the image source component to move. A preload member is disposed on the output assembly, and under the action of the preload member, the columnar structure generates a preload force with at least one of the piezoelectric actuator and the output assembly; When the piezoelectric actuator is not applying any force, the output component remains relatively stationary with respect to the columnar structure under the action of the preload force. When the piezoelectric actuator applies a force, the output component can move along the columnar structure, thereby moving the image source component.
2. The optical module according to claim 1, wherein Under the action of the pre-tightening member, the coefficient of friction between the columnar structure and one of the piezoelectric actuator and the output assembly is 0.1 to 0.3, and the pre-tightening force is 30 gf to 500 gf.
3. The optical module according to claim 1, wherein, The preload member elastically abuts against the columnar structure, so that the columnar structure and the output component have the preload force; The piezoelectric actuator is located at one end of the columnar structure. The piezoelectric actuator can drive the columnar structure to reciprocate along the length of the columnar structure, thereby driving the output component to move along the length of the columnar structure.
4. The optical module according to claim 3, wherein When the piezoelectric actuator applies a force to the columnar structure, and the columnar structure moves at a speed less than a set speed, the columnar structure can drive the output component to move synchronously. When the piezoelectric actuator applies a force to the columnar structure, and the columnar structure moves at a speed greater than or equal to a set speed, the output component is fixed relative to the support, while the columnar structure can move relative to the output component.
5. The optical module according to claim 1, wherein The columnar structure is connected to the bracket, and the output component is connected to the piezoelectric actuator; The preload member elastically abuts against the piezoelectric actuator, so that the piezoelectric actuator and the columnar structure have the preload force; Under the influence of voltage, the piezoelectric actuator can move linearly along the columnar structure and drive the output component to move.
6. The optical module according to claim 5, wherein The output component includes a sliding component and a mounting component, wherein the sliding component is connected to the image source component; The mounting assembly is slidably connected to the columnar structure; Both the preload element and the piezoelectric actuator are disposed on the mounting assembly; The preload member presses the drive end of the piezoelectric actuator against the columnar structure, allowing the piezoelectric actuator to move along the columnar structure and thus move the sliding assembly.
7. The optical module according to any one of claims 1 to 6, wherein The image source assembly includes at least one of a display component and a lens.
8. The optical module according to claim 7, wherein When the image source assembly includes a display component and a lens, the image source assembly is configured in any of the following ways: The image source component is integrally disposed on the output component, and the display component and lens of the image source component are located on both sides of the output component along the direction of movement; The image source component is integrally disposed on the output component, the display component and the lens of the image source component are located on the same side of the output component, and the display component is attached to the output component; The display component of the image source assembly is disposed on the output assembly, and the lens of the image source assembly is disposed on the bracket.
9. A focusing optical system, comprising: The optical module as described in any one of claims 1-8; An optical component is provided, which is mounted on a bracket along with an optical module. The output component of the optical module drives the image source component to move, thereby adjusting the distance between the image source component and the optical component. The light emitted by the image source component can be projected onto the optical component, and the optical component can adjust the optical path of the light emitted by the image source component.
10. A head-mounted display device, comprising: frame; The adjustable-focus optical system as claimed in claim 9, wherein the adjustable-focus optical system is disposed on the frame.
11. The head-mounted display device of claim 10, wherein, Includes ranging components and ranging mating parts; The ranging component is mounted on the bracket; The ranging component is disposed on the output component, and the ranging element is used to detect the distance between itself and the ranging component.