A near-eye display device and defogging control method

Abstract

The application discloses a near-eye display device and a defogging control method. The near-eye display device comprises a device body, the device body comprising a frame body and a lens arranged in the frame body; a plurality of piezoelectric ceramic sheets arranged on opposite sides of the lens; the plurality of piezoelectric ceramic sheets arranged on the same side of the lens are arranged at intervals along the edge of the lens; a driving module arranged inside the device body; the driving module is electrically connected with the plurality of piezoelectric ceramic sheets respectively, and the driving module is used for outputting a driving voltage to drive the plurality of piezoelectric ceramic sheets to vibrate, so as to drive the lens to vibrate. According to the application, the piezoelectric ceramic sheets are directly arranged on the edges of the lens, the driving module outputs the driving voltage to make the piezoelectric ceramic sheets produce controlled vibration, and then the lens is driven to vibrate to realize in-situ defogging. The user can remove the device or use an external cleaning device to remove the fog on the surface of the lens, so that the application experience of the near-eye display device is optimized, and the application scenarios of the near-eye display device are expanded.

Description

Technical Field

[0001] This application relates to the field of electronic technology, specifically to a near-eye display device and a defogging control method. Background Technology

[0002] With the increasing popularity of smart glasses such as augmented reality (AR) and virtual reality (VR) glasses, users' demands for lens optical clarity are rising. However, fogging is a particularly prominent issue with smart glasses. Specifically, when wearers move from a low-temperature environment to a high-temperature, high-humidity environment, or exhale warm, humid air while wearing a mask, the lens surface temperature drops below the ambient dew point, causing water vapor to condense rapidly and form a fog layer, severely obstructing vision. For smart glasses, fogging not only affects the visual experience but can also impact optical display performance, posing significant safety hazards.

[0003] Currently, there are technologies that use ultrasound to clean lenses, but most of them are standalone external cleaning devices. Users need to place their glasses into the device to complete the cleaning, which cannot remove fog from the lens surface in place and in a timely manner while the glasses are being worn, thus failing to meet the real-time defogging needs in outdoor or mobile scenarios.

[0004] Therefore, the technology still needs to be improved and enhanced. Summary of the Invention

[0005] This application provides a near-eye display device and a defogging control method, which can automatically and in real-time defogging control of the near-eye display device, thereby optimizing the user experience of the near-eye display device and facilitating the expansion of the application scenarios of the near-eye display device.

[0006] This application provides a near-eye display device, which includes: The device body includes a frame and a lens disposed within the frame; Multiple piezoelectric ceramic sheets are disposed on opposite sides of the lens; multiple piezoelectric ceramic sheets located on the same side of the lens are spaced apart along the edge of the lens; The drive module is located inside the device body. The drive module is electrically connected to multiple piezoelectric ceramic sheets. The drive module is used to output drive voltage to drive the multiple piezoelectric ceramic sheets to vibrate, thereby causing the lens to vibrate.

[0007] In some embodiments of the near-eye display device, a plurality of piezoelectric ceramic sheets located on the same side of the lens are arranged in at least one column.

[0008] In some embodiments of the near-eye display device, a buffer structure layer is provided between the piezoelectric ceramic sheet and the lens.

[0009] In some embodiments of the near-eye display device, the buffer structure layer is a transparent structure layer.

[0010] In some embodiments of the near-eye display device, the driving voltage includes a first driving voltage and a second driving voltage, wherein the waveform of the first driving voltage is a continuous waveform and the waveform of the second driving voltage is a pulse waveform.

[0011] In some embodiments of the near-eye display device, the frequency of the first driving voltage is less than the frequency of the second driving voltage.

[0012] In some embodiments of the near-eye display device, the waveform amplitude of the first driving voltage is smaller than the waveform amplitude of the second driving voltage.

[0013] In some embodiments of the near-eye display device, the driving module includes a plurality of driving units, each driving unit being configured in a one-to-one correspondence with a plurality of piezoelectric ceramic sheets, and each driving unit being used to drive the corresponding piezoelectric ceramic sheet.

[0014] In some embodiments of the near-eye display device, the piezoelectric ceramic sheet includes a first electrode layer, a piezoelectric thin film layer and a second electrode layer, wherein the piezoelectric thin film layer is located between the first electrode layer and the second electrode layer. Each piezoelectric ceramic sheet has a first electrode layer containing an electrode sheet, the electrode sheet having a first electrode line for electrical connection with a corresponding drive unit; The second electrode layer has at least one second electrode line, which is used for grounding.

[0015] In some embodiments of the near-eye display device, the driving unit includes at least one driving branch, the driving branch including: The switching transistor has a first terminal for receiving a control signal, a second terminal for receiving a power supply voltage, and a third terminal electrically connected to the first electrode line for outputting a drive voltage to the corresponding electrode plate. The energy storage capacitor has one end connected to the third terminal of the switching transistor, and the other end grounded.

[0016] In some embodiments of the near-eye display device, the near-eye display device further includes: A photosensor is placed around the periphery of the lens. The photosensor is used to detect the intensity of light passing through the lens and outputs a light intensity detection signal.

[0017] In some embodiments of the near-eye display device, the near-eye display device further includes: A temperature difference sensor is placed around the periphery of the lens to detect the temperature difference between the lens and the current environment.

[0018] In some embodiments of the near-eye display device, the near-eye display device further includes: A humidity sensor is placed around the periphery of the lens to detect the humidity level of the environment in which the lens is located.

[0019] This application embodiment also provides a defogging control method, which is applied to the above-mentioned near-eye display device. The defogging control method includes: Obtain the defogging control command and determine the drive parameters of the drive module based on the defogging control command. The drive parameters include one or more of the following: drive voltage, drive current, or drive frequency. The drive module controls the vibration of the piezoelectric ceramic sheet based on the drive parameters.

[0020] In some embodiments of the defogging control method, the driving parameters include at least one of the following: waveform type of driving voltage, duty cycle, pulse width, output duration, intermittent period, and driving phase relationship between multiple piezoelectric ceramic sheets.

[0021] In some embodiments of the defogging control method, the defogging control method further includes: Acquire the light intensity detection signal output by the photosensitive sensor; The transmittance of the lens is determined based on the light intensity detection signal, and a defogging control command is generated when the transmittance is less than a preset threshold.

[0022] In some embodiments of the defogging control method, the defogging control method further includes: Obtain the temperature difference output by the temperature difference sensor; When the temperature difference exceeds the preset temperature threshold, a defogging control command is generated.

[0023] In some embodiments of the defogging control method, the defogging control method further includes: Obtain the humidity value from the humidity sensor; When the humidity value reaches the preset humidity threshold, a defogging control command is generated.

[0024] In the near-eye display device and defogging control method provided in this application embodiment, by directly arranging piezoelectric ceramic sheets on both sides of the lens, the drive module outputs a drive voltage to cause the piezoelectric ceramic sheets to vibrate in a controlled manner, thereby driving the lens to vibrate and achieve in-situ defogging. Users do not need to remove the device or use an external cleaning device to instantly remove fog from the lens surface while wearing the device, thereby significantly improving the usability, safety and user experience of the near-eye display device in complex environments. Attached Figure Description

[0025] The technical solution and other beneficial effects of this application will become apparent from the following detailed description of specific embodiments in conjunction with the accompanying drawings.

[0026] Figure 1This is a schematic diagram of the structure of a near-eye display device provided in an embodiment of this application.

[0027] Figure 2 This is a structural block diagram of the driving module and piezoelectric ceramic sheet in a near-eye display device provided in an embodiment of this application.

[0028] Figure 3 This is a schematic diagram showing the relationship between the polarization direction and the vibration direction of the piezoelectric ceramic sheet in the near-eye display device provided in this application embodiment.

[0029] Figure 4 This is a schematic diagram showing the arrangement of piezoelectric ceramic sheets in a near-eye display device provided in an embodiment of this application.

[0030] Figure 5 A schematic diagram of the vibration of a piezoelectric ceramic sheet in a near-eye display device provided in an embodiment of this application.

[0031] Figure 6 This is a schematic diagram showing the distribution of the buffer structure layer in the near-eye display device provided in an embodiment of this application.

[0032] Figure 7 This is a schematic diagram of a first distribution of the hydrophobic and antifouling film layer in a near-eye display device provided in an embodiment of this application.

[0033] Figure 8 This is a schematic diagram of a second distribution of the hydrophobic and antifouling film layer in a near-eye display device provided in an embodiment of this application.

[0034] Figure 9 This is a schematic diagram of the structure of the piezoelectric ceramic sheet in the near-eye display device provided in the embodiments of this application.

[0035] Figure 10 This is a schematic diagram showing the arrangement of electrode plates in a piezoelectric ceramic sheet in a near-eye display device provided in an embodiment of this application.

[0036] Figure 11 This is a structural block diagram of the driving unit and piezoelectric ceramic sheet in a near-eye display device provided in an embodiment of this application.

[0037] Figure 12 The circuit structure diagram of the driving subunit in the near-eye display device provided in the embodiments of this application is shown.

[0038] Figure 13 This is a schematic diagram of the output waveform of the driving subunit in the near-eye display device provided in the embodiments of this application.

[0039] Figure 14 This is a structural block diagram of the controller and sensor in a near-eye display device provided in an embodiment of this application.

[0040] Figure 15This is a schematic diagram of the first process of the defogging control method provided in the embodiments of this application.

[0041] Figure 16 This is a schematic diagram of a second process for the defogging control method provided in an embodiment of this application.

[0042] Figure 17 This is a schematic diagram of the third process of the defogging control method provided in the embodiments of this application.

[0043] Figure 18 This is a schematic diagram of the fourth process of the defogging control method provided in the embodiments of this application. Detailed Implementation

[0044] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0045] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Features thus defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0046] This application provides a near-eye display device and a defogging control method, which enables automatic defogging of the near-eye display device, thereby optimizing the user experience and expanding its application scenarios. Specific embodiments are described below to illustrate the near-eye display device and the defogging control method in detail.

[0047] Please see Figure 1 This application provides a near-eye display device, which includes a device body 110, multiple piezoelectric ceramic sheets 120, and a driving module 130. The device body 110 includes a frame 111 and lenses 112 disposed within the frame 111. The frame 111 is used to house and protect the lenses 112, the driving module 130, the battery, the optical display module, and other functional components, and to provide wearing support for the user. The frame 111 can be made of plastic, metal, composite materials, or a combination thereof, and its shape can be designed according to the specific type of near-eye display device, such as AR glasses, VR glasses, smart glasses, head-mounted displays, etc.

[0048] Lens 112 is disposed within frame 111 and is used to present external ambient light and / or image light emitted by the optical display module to the user's eyes. Lens 112 may be a display lens 112 integrating optical elements such as waveguides, gratings, and semi-transparent / semi-reflective films. It should be noted that, in the embodiments of this application, "lens 112" generally refers to an optical component located in front of the user's eyes in a near-eye display device that has light-transmitting function, and its specific form is not limited to a single lens.

[0049] Multiple piezoelectric ceramic sheets 120 are disposed on opposite sides of the lens 112. Opposite sides refer to the left and right sides or the top and bottom sides of the lens 112 in the horizontal line of sight of both eyes; preferably, they are disposed on the left and right sides of the lens 112. These piezoelectric ceramic sheets 120 can be disposed on opposite sides of the outer surface of the lens 112 facing the external environment, or on opposite sides of the inner surface facing the user's face, or simultaneously on corresponding sides of both the outer and inner surfaces. In actual assembly, the piezoelectric ceramic sheets 120 can be fitted, embedded, or snapped onto the edge area of ​​the lens 112 to avoid obstructing the central effective optical area of ​​the lens 112. The number of piezoelectric ceramic sheets 120 can be set according to the size, shape, weight of the lens 112, and the required defogging effect; for example, two, three, four, or more can be disposed on each side.

[0050] In this design, multiple piezoelectric ceramic sheets 120 located on the same side of the lens 112 are spaced apart along the edge of the lens 112, meaning that a certain distance is maintained between adjacent piezoelectric ceramic sheets 120, so as to form distributed excitation points at the edge of the lens 112. This spaced arrangement helps to form a uniform vibration field on the surface of the lens 112 and avoids the concentration of vibration energy in individual areas.

[0051] Please refer to the following: Figure 2 In this embodiment, the drive module 130 is disposed inside the device body 110. The drive module 130 is electrically connected to multiple piezoelectric ceramic sheets 120, and is used to output a drive voltage to drive the multiple piezoelectric ceramic sheets 120 to vibrate, thereby causing the lens 112 to vibrate. The electrical connection between the drive module 130 and the piezoelectric ceramic sheets 120 can be achieved through a flexible circuit board, conductive adhesive, metal spring, or welded wires to ensure the reliability of the connection and vibration resistance.

[0052] The piezoelectric ceramic sheet 120 refers to a sheet-like driving element made of piezoelectric material, which can realize the mutual conversion of mechanical energy and electrical energy. In this embodiment, the inverse piezoelectric effect of the piezoelectric ceramic sheet 120 is utilized: when the driving module 130 applies an alternating driving voltage to the piezoelectric ceramic sheet 120, the piezoelectric ceramic sheet 120 will repeatedly expand, contract, or bend with changes in voltage polarity and amplitude, thereby generating high-frequency mechanical vibration. This vibration is transmitted to the lens 112 through the mechanical connection between the piezoelectric ceramic sheet 120 and the lens 112, causing the lens 112 to generate micro-amplitude vibrations at the same frequency or harmonics. The vibration of the lens 112 will generate an acceleration field and surface acoustic waves on its surface, disrupting the adhesion balance between water droplets and the surface of the lens 112. Under the combined action of inertial force, surface tension gradient, acoustic radiation pressure, and boundary layer disturbance, the condensed water droplets will coalesce, break up, or roll off, thereby achieving the purpose of defogging.

[0053] Please see Figure 3 Specifically, the piezoelectric ceramic sheet 120 has a polarization direction P. When the driving module 130 applies an alternating driving voltage Vin that varies along the polarization direction P to the piezoelectric ceramic sheet 120, the piezoelectric ceramic sheet 120 reciprocates and expands along the thickness direction T under the action of the inverse piezoelectric effect. In the figure, arrow P represents the polarization direction of the piezoelectric ceramic sheet 120, and double arrow T represents the vibration direction of the piezoelectric ceramic sheet 120 under electric field excitation. As shown in the figure, the polarization direction P and the vibration direction T are parallel to each other, that is, the piezoelectric ceramic sheet 120 works in a longitudinal vibration mode: when the driving voltage Vin is in the positive half-cycle, the piezoelectric ceramic sheet 120 elongates along the thickness direction; when the driving voltage Vin is in the negative half-cycle, the piezoelectric ceramic sheet 120 contracts along the thickness direction. With the continuous change of the sinusoidal driving voltage, the piezoelectric ceramic sheet 120 generates high-frequency reciprocating vibration in the thickness direction T.

[0054] It should be noted that the parallelism between the vibration direction T and the polarization direction P of the piezoelectric ceramic sheet 120 only indicates that its main working mode is longitudinal vibration. In actual assembly, the way the piezoelectric ceramic sheet 120 is attached to the edge of the lens 112 will cause the longitudinal vibration to simultaneously excite the bending wave and shear wave of the lens 112, thereby forming a complex composite vibration field on the surface of the lens 112, which further enhances the defogging effect.

[0055] In this application, the piezoelectric ceramic sheet 120 is directly arranged on both sides of the lens 112. The drive module 130 outputs a drive voltage to make the piezoelectric ceramic sheet 120 vibrate in a controlled manner, thereby causing the lens 112 to vibrate and achieve in-situ defogging. Users do not need to remove the device or use an external cleaning device to remove fog from the surface of the lens 112 while wearing it, thereby significantly improving the usability, safety and user experience of near-eye display devices in complex environments.

[0056] In some embodiments, multiple piezoelectric ceramic sheets 120 located on the same side of the lens 112 are arranged in at least one column. On the left edge of the lens 112, six piezoelectric ceramic sheets 120 can be arranged in a column along the vertical direction; on the right edge of the lens 112, another six piezoelectric ceramic sheets 120 can also be arranged in a column along the vertical direction. The piezoelectric ceramic sheets 120 in each column can be arranged at equal intervals, or non-equal intervals can be used depending on the curvature of the edge of the lens 112 and the force requirements.

[0057] Please see Figure 4 and Figure 5 It should be noted that the piezoelectric ceramic sheets 120 are preferably disposed on the left and right edges of the lens 112, and can be arranged in one or more strips along each edge. Compared with the vertical arrangement, the horizontal arrangement is more in line with the geometric characteristics and vibration mode distribution of the lens 112: On the one hand, the width of the lens 112 in the near-eye display device is usually greater than its height in the vertical direction. Arranging the piezoelectric ceramic sheets 120 on the left and right sides allows the excitation source to be closer to the horizontal center line of the optical area of ​​the lens 112, thereby forming a more uniform and stronger vibration energy distribution in the central area of ​​the lens 112; on the other hand, the piezoelectric ceramic sheets 120 on the left and right sides can excite bending waves in the horizontal direction. This type of vibration wave has a longer propagation distance and slower attenuation in the horizontal direction, which can cover a larger area of ​​the lens 112 and reduce the vibration blind zone.

[0058] Please see Figure 5 In some embodiments, a buffer structure layer 140 is provided between the piezoelectric ceramic sheet 120 and the lens 112. This buffer structure layer 140 is located between the surfaces of the piezoelectric ceramic sheet 120 and the lens 112, and is used to absorb and homogenize the mechanical impact between them, thereby improving vibration transmission characteristics. The piezoelectric ceramic sheet 120 efficiently couples vibrations to the surface of the lens 112 through the buffer structure layer 140, generating uniform in-plane micro-vibrations. Defogging is achieved using cavitation effects and interfacial shear forces. The transparent buffer structure layer 140 can be made of materials such as optically transparent adhesive, transparent silicone pads, transparent polyurethane films, or transparent acrylic adhesives.

[0059] Please see Figure 6 In this embodiment, by setting a buffer structure layer 140 between the piezoelectric ceramic sheet 120 and the lens 112, the interface stress and mechanical impact between the piezoelectric ceramic sheet 120 and the lens 112 can be effectively reduced, preventing microcracks or coating damage to the lens 112 due to long-term high-frequency vibration, and extending the service life of the equipment. At the same time, the buffer structure layer 140 optimizes the vibration transmission path, so that the vibration energy of the piezoelectric ceramic sheet 120 is coupled to the lens 112 more evenly, improving the consistency of the defogging effect.

[0060] In some embodiments, the buffer structure layer 140 is a transparent structure layer. A transparent structure layer refers to a structure layer with high transmittance of visible light, which can be greater than 80%, preferably greater than 90%. By using a transparent buffer structure layer, even if the buffer structure layer 140 extends slightly into the central visible area of ​​the lens 112 during assembly, it will not significantly affect the user's visual experience and optical display effect.

[0061] Please see Figure 7 As one embodiment, the surface of the lens 112 is further provided with a hydrophobic and antifouling film layer 150. The hydrophobic and antifouling film layer 150 covers the central optical area of ​​the lens 112 and is used to reduce the adhesion strength of water mist, oil stains and fingerprints on the surface of the lens 112, so that condensed water droplets can more easily slide off or roll away under the vibration driven by the piezoelectric ceramic sheet 120. The hydrophobic and antifouling film layer 150 can be made of materials such as fluoropolymers, siloxane polymers, nano-silica composite materials or diamond-like carbon coatings. Its water contact angle can be greater than 90 degrees, preferably greater than 110 degrees, and its oil contact angle can be greater than 60 degrees, thereby achieving good hydrophobic and oleophobic effects.

[0062] Please see Figure 8 In another embodiment, the piezoelectric ceramic sheet 120 is disposed on the back side of the lens 112, and the hydrophobic and antifouling film layer 150 is disposed on the front side of the lens 112. In this case, the front side of the lens 112 can be completely covered by the hydrophobic and antifouling film layer 150, unaffected by the installation of the piezoelectric ceramic sheet 120; the back side where the piezoelectric ceramic sheet 120 is located may not have the hydrophobic and antifouling film layer 150, or may only have a functional film layer that does not affect adhesion. This method is simple in process, minimizes mutual interference, and is suitable for near-eye display devices where piezoelectric ceramic sheets 120 can be arranged on both sides.

[0063] In this embodiment, by providing a hydrophobic and antifouling film layer 150 on the surface of the lens 112, the adhesion of water mist, oil stains and fingerprints on the surface of the lens 112 can be reduced, forming a synergistic effect with the vibration defogging of the piezoelectric ceramic sheet 120, thereby improving the defogging and cleaning efficiency.

[0064] In some embodiments, the driving voltage output by the driving module 130 includes a first driving voltage and a second driving voltage. The waveform of the first driving voltage is a continuous waveform, and the waveform of the second driving voltage is a pulse waveform. The continuous waveform can be a periodic waveform such as a sine wave, a triangular wave, a sawtooth wave, or a continuous square wave. The continuous waveform has the characteristics of stable energy output, controllable harmonic components, and stable vibration state of the piezoelectric ceramic sheet 120, and is suitable for sustained defogging or slight fogging scenarios. The pulse waveform can be a single pulse, a double pulse, a pulse train, or a pulse-modulated waveform, which has the characteristics of high instantaneous energy, large peak amplitude, and strong defogging impact, and is suitable for removing thick fog layers, large water droplets, or stubborn water stains.

[0065] As one embodiment, the frequency of the first driving voltage is lower than the frequency of the second driving voltage. For example, the frequency of the first driving voltage can be in a lower frequency ultrasonic band of 20 kHz to 80 kHz, and the frequency of the second driving voltage can be in a higher frequency ultrasonic band of 100 kHz to 500 kHz.

[0066] As one embodiment, the waveform amplitude of the first driving voltage is smaller than that of the second driving voltage. Waveform amplitude refers to the peak voltage or peak-to-peak voltage of the driving voltage. Specifically, the first driving voltage, as a normal, sustained vibration, can be set to an amplitude of 5V to 20V. Within this voltage range, the piezoelectric ceramic sheet 120 undergoes a small degree of mechanical deformation under the inverse piezoelectric effect. After being transmitted to the lens 112 through the buffer structure layer, the vibration displacement amplitude on the surface of the lens 112 is correspondingly within the range of 0.1μm to 1μm. This micro-amplitude continuous vibration can be used to achieve a low-energy-consumption defogging mode. In this defogging mode, the driving module 130 outputs a lower amplitude first driving voltage, causing the piezoelectric ceramic sheet 120 to produce small-amplitude continuous vibration, maintaining the dryness of the lens 112 surface and preventing water vapor condensation. The second driving voltage, as an enhanced defogging pulse, can be set to an amplitude of 20V to 150V. Compared to the first driving voltage, the second driving voltage has a significantly increased amplitude, causing the piezoelectric ceramic sheet 120 to undergo greater mechanical deformation. After being transmitted through the buffer structure layer, the vibration displacement amplitude on the surface of the lens 112 is correspondingly increased to the range of 1μm to 3μm. This larger amplitude pulse vibration can be used in a powerful cleaning mode. In this cleaning mode, the driving module 130 outputs a higher amplitude second driving voltage, causing the piezoelectric ceramic sheet 120 to generate large-amplitude pulse vibrations, quickly removing fog, larger water droplets, or stubborn water stains.

[0067] It should be noted that the correspondence between the voltage amplitude and displacement amplitude is not fixed, but depends on the piezoelectric coefficient, geometric dimensions, polarization direction of the piezoelectric ceramic sheet 120, the mechanical coupling efficiency between the piezoelectric ceramic sheet 120 and the lens 112, the elastic modulus of the buffer structure layer, and the stiffness and boundary constraints of the lens 112 itself. This application does not impose specific limitations on these aspects.

[0068] Please refer to the following: Figure 9 In some embodiments, the driving module 130 includes a plurality of driving units 131, which are configured one-to-one with a plurality of piezoelectric ceramic sheets 120. Each driving unit 131 is used to drive the corresponding piezoelectric ceramic sheet 120.

[0069] The drive unit 131 can be independently controlled according to the position and function of the corresponding piezoelectric ceramic sheet 120. For example, when the fogging is severe on the left side of the lens 112, the output power of the drive unit 131 corresponding to the left piezoelectric ceramic sheet 120 can be increased only, while the right piezoelectric ceramic sheet 120 remains at a lower power or is turned off; when the fogging is symmetrical on both sides of the lens 112, the drive power of both piezoelectric ceramic sheets 120 can be increased simultaneously. The independence between the drive units 131 also improves the redundancy of the system, that is, when a drive unit 131 or a piezoelectric ceramic sheet 120 fails, the other drive units 131 can still work normally, and the entire defogging function will not fail completely.

[0070] In this embodiment, by including a drive unit 131 in the drive module 130 that corresponds one-to-one with the piezoelectric ceramic sheet 120, each piezoelectric ceramic sheet 120 can be independently controlled, realizing fine adjustment of drive parameters and fault isolation; when a certain piezoelectric ceramic sheet 120 fails, it does not affect the normal operation of other piezoelectric ceramic sheets 120, thereby improving the redundancy of the system.

[0071] Please see Figure 10 and Figure 11 In some embodiments, the piezoelectric ceramic sheet 120 includes a first electrode layer 121, a piezoelectric thin film layer 122, and a second electrode layer 123. The piezoelectric thin film layer 122 is located between the first electrode layer 121 and the second electrode layer 123, forming a sandwich structure. Each electrode sheet 1211 has a first electrode line 1212 for electrical connection with a corresponding driving unit 131. The second electrode layer 123 is a common electrode layer covering the entire surface, and at least one second electrode line is led out from the second electrode layer 123 for grounding.

[0072] The piezoelectric thin film layer 122 is made of a piezoelectric material, such as lead zirconate titanate (PZT), barium titanate (BaTiO3), polyvinylidene fluoride (PVDF), or composite materials thereof. The first electrode layer 121 and the second electrode layer 123 are made of conductive materials, such as silver paste, gold, platinum, indium tin oxide (ITO), or conductive polymers. The electrode pieces 1211 in the first electrode layer 121 can be circular, square, strip-shaped, or other geometric shapes, and multiple electrode pieces 1211 can be arranged in a rectangular array, a ring array, or a concentric circle array. Each electrode piece 1211 is electrically independent and can receive a driving voltage provided by the driving module 130.

[0073] The second electrode layer 123 serves as a common electrode layer, covering the entire or most surface of the piezoelectric thin film layer 122 and grounded via the second electrode line. When the driving module 130 applies a driving voltage to the electrode sheet 1211 via the first electrode line 1212, an electric field is formed between the electrode sheet 1211 and the second electrode layer 123, causing local deformation in the region of the piezoelectric thin film layer 122 beneath the electrode sheet 1211. Therefore, by independently controlling the driving voltage of different electrode sheets 1211, local driving of different regions of the piezoelectric ceramic sheet 120 can be achieved, thereby enabling independent adjustment of the vibration intensity of different regions of the lens 112.

[0074] As one example, such as Figure 11 As shown, when there are multiple electrode sheets 1211 in the first electrode layer 121, the multiple electrode sheets 1211 are arranged in an array. In this embodiment, by arranging the multiple electrode sheets 1211 in an array, the first electrode layer 121 can be divided into multiple relatively independent driving regions, thereby facilitating the driving unit 131 to apply driving voltages to different electrode sheets 1211 respectively. As a result, different regions of the piezoelectric ceramic sheet 120 can produce corresponding deformations under the action of the corresponding driving voltage, enabling the piezoelectric ceramic sheet 120 to achieve zoned driving or local deformation control, improving the adjustability of vibration mode or bending direction.

[0075] Meanwhile, the array arrangement of multiple electrode sheets 1211 also helps to improve the uniformity of the distribution of electrode sheets 1211 on the piezoelectric ceramic sheet 120, making the driving action more balanced, reducing local stress concentration, and thus improving the driving stability and reliability of the piezoelectric ceramic sheet 120.

[0076] It should be noted that the multiple electrode sheets 1211 can be arranged in a regular row and column manner, or they can be arranged at non-equal intervals according to the shape of the piezoelectric ceramic sheet 120, the driving area, or the target deformation mode. This application does not limit this arrangement.

[0077] Please see Figure 12 In one embodiment, the drive unit 131 includes at least one drive branch, which includes a switching transistor 1311 and an energy storage capacitor 1312. A first terminal of the switching transistor 1311 is used to receive a control signal, a second terminal is used to receive a power supply voltage, and a third terminal is used to be electrically connected to the first electrode line 1212 of the corresponding electrode in the piezoelectric ceramic sheet 120, for outputting a drive voltage to the corresponding electrode 1211. One end of the energy storage capacitor 1312 is connected to the third terminal of the switching transistor 1311, and the other end of the energy storage capacitor 1312 is grounded.

[0078] When the first electrode layer 121 includes multiple electrode pieces 1211, the driving unit 131 can provide a corresponding driving branch for each electrode piece 1211. That is, each electrode piece 1211 can be provided with a switching transistor 1311 and an energy storage capacitor 1312 to control the driving voltage of the multiple electrode pieces 1211 respectively. Of course, in other embodiments, the multiple electrode pieces 1211 can also share some driving elements, as long as they can provide driving voltage to the corresponding electrode pieces 1211 separately or in groups.

[0079] In this embodiment, the switch 1311 can be a thin-film transistor (TFT), a metal-oxide-semiconductor field-effect transistor (MOSFET), a bipolar junction transistor (BJT), an insulated gate bipolar transistor (IGBT), or other controllable switching devices.

[0080] Taking the driving unit 131 using a thin-film transistor (TFT) as the switching transistor 1311 as an example, the energy storage capacitor 1312 and the piezoelectric ceramic plate 120 are connected in parallel between the drain D of the switching transistor 1311 and ground. In the figure, the Gate terminal is the gate control terminal of the switching transistor 1311, used to receive control signals from the controller; the S terminal is the source terminal of the switching transistor 1311, used to connect to the boosted or regulated power supply voltage Vin; the D terminal is the drain of the switching transistor 1311, serving as the driving voltage output terminal, and is electrically connected to the electrode plate 1211 in the piezoelectric ceramic plate 120 and one end of the energy storage capacitor 1312, respectively. The other ends of the electrode plate 1211 and the energy storage capacitor 1312 are grounded together. Please refer to the following: Figure 13 To provide a high-frequency drive signal to the piezoelectric ceramic element 120, this embodiment applies a square wave switching signal with a frequency reaching the ultrasonic band (e.g., greater than 40kHz) to the Gate terminal. Taking an 80kHz square wave frequency at the Gate terminal as an example: when the Gate terminal voltage is high, the switch 1311 is turned on, forming a conduction channel between the source (S) and drain (D). The power supply voltage Vin charges the energy storage capacitor 1312 and the piezoelectric ceramic element 120 through the switch 1311. Since the equivalent capacitance of the piezoelectric ceramic element 120 and the energy storage capacitor 1312 together form an RC charging circuit, the charging process is not instantaneous but requires a certain charging time t. Figure 13 As shown, the voltage at the drain D terminal rises in a stepwise manner during the charging time t, with each step corresponding to multiple conduction cycles of the Gate square wave, and the voltage gradually approaches the top level of the power supply voltage.

[0081] When the gate voltage goes low, the switch 1311 turns off, breaking the conduction path between the source (S) and drain (D). At this time, the energy storage capacitor 1312 maintains its charge, keeping the drain voltage at D relatively stable at a high level for the duration t1. Due to the combined effect of the equivalent capacitance of the piezoelectric ceramic plate 120 and the energy storage capacitor 1312, this sustaining phase is not perfectly flat; instead, a slow voltage drop occurs, forming a slightly downward-sloping envelope at the top of the waveform. Subsequently, when the gate re-enters the appropriate control state, the energy storage capacitor 1312 and the piezoelectric ceramic plate 120 discharge through an external circuit, causing the drain voltage at D to decrease in a stepwise manner during the discharge time t, gradually returning to a low level. The above charging, sustaining, and discharging processes together constitute the output waveform, which approximates the upper half of a sine wave.

[0082] To obtain a complete sinusoidal drive voltage, the drive module 130 controls the switching of the switching transistor 1311 between different polarity power supplies, causing the drain terminal (D) to output a reverse voltage. Specifically, after generating the positive half-cycle waveform, the conduction path or polarity configuration of the switching transistor 1311 is changed, causing the energy storage capacitor 1312 and the piezoelectric ceramic plate 120 to charge, maintain, and discharge in opposite directions, thereby supplementing the lower half of the sine wave. By alternating the output of the positive and reverse half-cycles, a complete high-frequency sinusoidal alternating drive voltage can be formed across the piezoelectric ceramic plate 120.

[0083] In this embodiment, the first driving voltage can be the aforementioned approximately sinusoidal continuous waveform. Since the gate terminal square wave frequency is relatively high (e.g., 80kHz), and the mechanical response time of the piezoelectric ceramic sheet 120 is much longer than the switching period of the electrical signal, the piezoelectric ceramic sheet 120 mechanically only responds to the envelope change of the drain terminal D voltage, thus generating stable ultrasonic vibration with low mechanical loss. The second driving voltage can achieve pulse output by changing the duty cycle, amplitude, or interval period of the gate terminal square wave: when a pulse waveform needs to be output, the controller outputs multiple gate square wave cycles continuously for a short period, causing the energy storage capacitor 1312 to quickly charge to a high level and then quickly discharge, forming a high-amplitude pulse envelope; during the pulse interval, the gate terminal remains off, the drain terminal D voltage returns to zero, and the piezoelectric ceramic sheet 120 stops vibrating or only maintains weak vibration.

[0084] In this embodiment, the energy storage capacitor 1312 is connected in parallel between the output terminal of the switching transistor 1311 and ground. The capacitance value of the energy storage capacitor 1312 can be selected according to the frequency of the driving voltage, the equivalent capacitance of the piezoelectric ceramic plate 120, and the allowable voltage ripple. The energy storage capacitor 1312 is used to store charge during the conduction period of the switching transistor 1311 and release energy to the piezoelectric ceramic plate 120 during the turn-off period to maintain the continuity of the output voltage; at the same time, the energy storage capacitor 1312 can be used to filter out high-frequency noise and voltage spikes during the switching process, protecting the piezoelectric ceramic plate 120.

[0085] In this embodiment, by setting a switching transistor 1311 and an energy storage capacitor 1312 in the driving unit 131, the switching transistor 1311 can quickly switch between on and off states under the action of a control signal, and deliver the power supply voltage to the corresponding electrode in a pulse or continuous manner; the energy storage capacitor 1312 can store charge during the on period of the switching transistor 1311 conduction and release energy during the off period, playing a filtering role, making the driving voltage waveform output to the piezoelectric ceramic sheet 120 more stable, reducing the impact of power supply ripple on vibration consistency, and thus improving the reliability of the driving circuit and the defogging effect.

[0086] Please see Figure 14 In some embodiments, the near-eye display device further includes a photosensor 160. The photosensor 160 is disposed at the periphery of the lens 112 and is used to detect the light intensity transmitted through the lens 112 and output a light intensity detection signal.

[0087] Multiple photosensitive sensors 160 are arranged at different peripheral positions of the lens 112, such as the upper edge, lower edge, left edge, and right edge. By arranging multiple photosensitive sensors 160 at different positions, the difference in transmitted light intensity in different areas of the lens 112 can be detected, thereby determining the spatial distribution of fogging. The detection light of the photosensitive sensors 160 can be ambient natural light, ambient artificial light, or display light emitted by the display module inside the near-eye display device. When the surface of the lens 112 is clear, the incident light mainly undergoes transmission and regular reflection, and the transmitted light intensity received by the photosensitive sensors 160 is high. When the surface of the lens 112 is fogged, water droplets scatter, absorb, and diffusely reflect the incident light, resulting in a significant decrease in transmitted light intensity. Therefore, the light intensity detection signal output by the photosensitive sensors 160 can indirectly reflect the degree of fogging and light transmittance of the lens 112.

[0088] In this embodiment, a photosensitive sensor 160 is set around the periphery of the lens 112. The photosensitive sensor 160 can detect changes in light intensity transmitted through the lens 112, indirectly reflecting the degree of fogging on the surface of the lens 112. When the lens 112 fogs up, the ambient light or display light transmitted through the lens 112 is scattered and attenuated, and the light intensity detection signal output by the photosensitive sensor 160 changes accordingly. This provides a real-time and direct basis for generating defogging control commands, realizes automatic triggering of defogging operation, and improves the timeliness and accuracy of defogging response.

[0089] In some embodiments, the near-eye display device further includes a temperature difference sensor 170. The temperature difference sensor 170 is disposed at the periphery of the lens 112 and is used to detect the temperature difference between the lens 112 and the current environment. The temperature difference sensor 170 may include two temperature-sensitive elements: one disposed close to or near the surface of the lens 112 for detecting the surface temperature of the lens 112; the other exposed to the environment for detecting the ambient temperature. The difference between the output signals of the two temperature-sensitive elements is the temperature difference between the lens 112 and the environment. The temperature difference sensor 170 may also be an integrated temperature measurement chip, such as a combination of a thermopile, an infrared temperature difference sensor 170, or a digital temperature difference sensor 170.

[0090] One of the physical conditions for fogging is that the surface temperature of the lens 112 is lower than the dew point temperature of the ambient air. When the temperature difference between the surface temperature of the lens 112 and the ambient temperature is large, it indicates that the surface of the lens 112 is relatively cold, and ambient water vapor is more likely to condense on the surface of the lens 112. Therefore, by monitoring the temperature difference in real time, the risk of fogging can be predicted before the fog layer forms, and defogging can be initiated in advance. The preset temperature threshold can be set according to the thermal conductivity characteristics of the lens 112 material, the range of ambient humidity, and user experience data, and this application does not limit this.

[0091] In this embodiment, a temperature difference sensor 170 is set around the lens 112 to detect the temperature difference between the surface temperature of the lens 112 and the current ambient temperature in real time. When the temperature difference reaches or exceeds the critical condition that causes ambient water vapor to condense on the surface of the lens 112, a defogging control command is generated to start defogging in advance, thereby achieving preventive defogging and avoiding the interruption of vision caused by clearing the fog layer after it has formed, thus improving the user experience and the active protection capability of the device.

[0092] In some embodiments, the near-eye display device further includes a humidity sensor 180. The humidity sensor 180 is disposed around the periphery of the lens 112 and is used to detect the humidity value of the environment surrounding the lens 112. The humidity sensor 180 may be a resistive humidity sensor 180, a capacitive humidity sensor 180, an electrolyte humidity sensor 180, or an integrated temperature and humidity sensor chip 180. The humidity sensor 180 should be arranged in a location that can represent the ambient air humidity around the lens 112, such as a ventilation area inside the frame 111 near the edge of the lens 112, in the gap between the lens 112 and the frame 111, or near a vent on the device body 110.

[0093] When the ambient humidity is high, even if the temperature difference between the surface of the lens 112 and the ambient temperature is not large, water vapor may still condense due to the high dew point temperature. Therefore, by monitoring the ambient humidity in real time, the risk of fogging can be assessed more comprehensively. The preset humidity threshold can be set according to different usage scenarios, such as 60% to 70% relative humidity in a normal indoor environment and 70% to 80% relative humidity in an outdoor sports environment. This application does not impose specific limitations on this.

[0094] In this embodiment, a humidity sensor 180 is set around the lens 112 to monitor the humidity value of the environment in which the lens 112 is located in real time. When the ambient humidity reaches or exceeds the preset humidity threshold, it indicates that the environment has the conditions for fogging. At this time, a defogging control command can be actively generated to start defogging, further improving the timeliness and initiative of defogging.

[0095] In some embodiments, the near-eye display device further includes a controller 190, which is electrically connected to at least one of the photosensor 160, the temperature difference sensor 170, and the humidity sensor 180. The controller 190 is used to receive the detection signals output by each sensor and generate control commands based on the detection signals to control the drive module 130 to output the corresponding drive voltage.

[0096] In actual configuration, one, two, or all three types of sensors can be selected and set according to requirements. When only one or two of the photosensitive sensor 160, temperature difference sensor 170, or humidity sensor 180 are set, the controller 190 is electrically connected to the corresponding one or two sensors; when all three types of sensors are set, the controller 190 is electrically connected to the photosensitive sensor 160, temperature difference sensor 170, and humidity sensor 180 simultaneously to achieve multi-dimensional environmental perception and precise defogging control.

[0097] In this embodiment, by setting up a controller 190 and electrically connecting it to at least one sensor, sensor detection, fogging judgment, and defogging control can be integrated into one, realizing the automation and intelligence of the defogging process. The controller 190 generates defogging control commands in real time based on sensor signals, and can start defogging at the appropriate time without manual intervention by the user, thereby improving the response speed and user experience of near-eye display devices.

[0098] Please see Figure 15 This application embodiment also provides a defogging control method, which is applied to the aforementioned near-eye display device. The controller 190 is used to execute the defogging control method, which includes steps S100 and S200, as follows: S100: Obtain the defogging control command and determine the driving parameters of the drive module 130 according to the defogging control command. The driving parameters include one or more of the following: driving voltage, driving current, or driving frequency.

[0099] The control commands can be issued by the user through physical buttons, touch areas, voice commands, or external terminal applications on the near-eye display device, or they can be automatically generated by the controller 190 inside the device based on sensor signals.

[0100] S200: Control the vibration of the piezoelectric ceramic sheet by controlling the drive module 130 according to the drive parameters.

[0101] Specifically, the drive module 130 generates a corresponding drive voltage according to the determined drive parameters and transmits it to the first electrode layer 121 and the second electrode layer 123 of the piezoelectric ceramic sheet 120 through an electrical connection; the piezoelectric thin film layer 122 in the piezoelectric ceramic sheet 120 generates the inverse piezoelectric effect under the action of the electric field, and undergoes mechanical deformation and vibration; the vibration is transmitted to the lens 112 through mechanical coupling, causing the lens 112 to generate high-frequency micro-amplitude vibration, thereby destroying the adhesion stability of water mist on the surface of the lens 112 and realizing defogging.

[0102] The driving parameters may also include at least one of the following: the waveform type, duty cycle, pulse width, output duration, intermittent period, and driving phase relationship between the multiple piezoelectric ceramic sheets 120 of the driving voltage. For example, in a slightly foggy scenario, a continuous sine wave driving voltage with a frequency of 40kHz and an amplitude of 10V can be output; in a severely foggy scenario, a pulse driving voltage with a frequency of 200kHz and an amplitude of 80V can be output and last for 500 milliseconds to 2 seconds; after rapid defogging is completed, a sustained continuous driving voltage with a frequency of 40kHz and an amplitude of 5V can be switched to keep the surface of the lens 112 dry.

[0103] In this embodiment, the driving parameters of the driving module 130 are determined by obtaining the defogging control command, and then the driving module 130 is controlled to drive the piezoelectric ceramic sheet 120 to vibrate according to the driving parameters, so as to achieve effective control of defogging and improve the intelligence level of near-eye display devices.

[0104] Please see Figure 16 As one embodiment, the control method further includes steps S101 and S102, as follows: S101. Acquire the light intensity detection signal output by the photosensitive sensor 160.

[0105] The controller 190 in the near-eye display device reads the analog or digital output of the photosensitive sensor 160 at a fixed sampling period, which can be set from 10 milliseconds to 1 second. When multiple photosensitive sensors 160 are set, the outputs of each photosensitive sensor 160 can be read sequentially, or a multi-channel synchronous sampling method can be used.

[0106] S102. Determine the transmittance of lens 112 based on the light intensity detection signal, and generate a defogging control command when the transmittance is less than a preset threshold.

[0107] Light transmittance can be obtained by comparing the current light intensity detection signal with a preset reference light intensity signal. The reference light intensity signal can be pre-calibrated under clear, fog-free conditions on the lens 112 surface, or it can be dynamically updated according to changes in ambient light. For example, light transmittance can be calculated as the ratio of the current light intensity detection signal to the reference light intensity signal, multiplied by 100% to obtain the transmittance in percentage form. When using multiple photosensors 160, the local transmittance of each area can be calculated separately, and then the average or minimum value can be taken as the overall transmittance.

[0108] Next, it is determined whether the light transmittance is less than a preset threshold. This preset threshold can be set according to the user's tolerance for fogging visibility, for example, set to 80%, 70%, or 60% of the baseline light transmittance. When the light transmittance is less than the preset threshold, it indicates that the fogging of lens 112 has significantly affected the user's vision, and a defogging control command is generated; otherwise, the detection continues. The defogging control command may include target driving parameters, such as driving mode (continuous mode, pulse mode, or combined mode), target frequency, target amplitude, and expected output duration. The controller 190 sends the defogging control command to the drive module 130, which then performs the defogging operation.

[0109] The defogging control method in this embodiment uses the light intensity detection signal output by the photosensitive sensor 160 to determine the light transmittance of the lens 112. When the light transmittance is less than a preset threshold, a control command is generated, which can realize closed-loop defogging control based on the actual optical transmittance performance of the lens 112.

[0110] Please see Figure 17 As one embodiment, the control method further includes steps S201 and S202, as follows: S201. Obtain the temperature difference output by the temperature difference sensor 170.

[0111] The controller 190 reads the output difference between the two temperature-sensitive elements in the temperature difference sensor 170 to obtain the temperature difference between the surface temperature of the lens 112 and the ambient temperature. To improve measurement accuracy, multiple sampling results can be averaged or filtered to eliminate the effects of instantaneous noise and airflow fluctuations.

[0112] S202. When the temperature difference is greater than the preset temperature threshold, a defogging control command is generated.

[0113] The acquired temperature difference is compared with a preset temperature threshold, which can be set according to the critical conditions for fogging. For example, when the ambient humidity is high, fogging may occur even if the temperature difference is only 2 to 3 degrees Celsius; when the ambient humidity is low, a temperature difference of more than 5 degrees Celsius may be required for fogging. Therefore, the preset temperature threshold can be adjusted in conjunction with the humidity value of the humidity sensor 180; the higher the humidity, the lower the preset temperature threshold. When the temperature difference is greater than the preset temperature threshold, a defogging control command is generated. The defogging control command can instruct the drive module 130 to output the drive voltage in preventative mode. The preventative defogging mode can prevent fogging before the fog layer forms, reducing the interruption of the user's field of vision. When the temperature difference further increases or the light transmittance also begins to decrease, the mode can be switched to enhanced defogging mode. When the temperature difference is less than the preset temperature threshold, detection continues. Thus, in this embodiment, by acquiring the temperature difference output by the temperature difference sensor 170 and generating a defogging control command when the temperature difference is greater than the preset temperature threshold, automatic defogging control is achieved.

[0114] Please see Figure 18 As one embodiment, the control method further includes steps S301 and S302, as follows: S301. Obtain the humidity value from humidity sensor 180.

[0115] In this embodiment, the controller 190 reads the ambient relative humidity value output by the humidity sensor 180 at a certain sampling period. For the integrated temperature and humidity sensor 180, temperature information can be acquired simultaneously for dew point calculation.

[0116] S302. When the humidity value reaches the preset humidity threshold, a defogging control command is generated.

[0117] After acquiring the humidity value, it is compared with a preset humidity threshold. The preset humidity threshold can be selected based on historical data statistics, user settings, or the current usage scenario. For example, in an indoor air-conditioned environment, the preset humidity threshold can be set to 65%; in rainy or humid environments, it can be set to 75%; and in dry environments, it can be set to trigger only when the humidity is above 80%. When the ambient humidity reaches the preset humidity threshold, it indicates that the current environment has conditions for fogging, and the controller 190 generates a control command to start defogging. At this time, if the temperature difference sensor 170 also detects a large temperature difference, it can be determined that the risk of fogging is high, and defogging is immediately carried out at a high intensity; if the temperature difference is small, it can first operate in a low-intensity maintenance mode, continuously monitoring the light transmittance and temperature difference changes.

[0118] In this embodiment, by acquiring the humidity value of the humidity sensor 180 and generating a control command when the humidity value reaches a preset humidity threshold, the risk of fogging can be identified from the environmental side, and automatic control of defogging can also be achieved.

[0119] In some embodiments, at least two of the following can be simultaneously provided in the near-eye display device: a photosensitive sensor 160, a temperature difference sensor 170, and a humidity sensor 180. Taking the simultaneous provision of the photosensitive sensor 160, the temperature difference sensor 170, and the humidity sensor 180 as an example, the controller 190 in the near-eye display device can simultaneously receive the light intensity detection signal output by the photosensitive sensor 160, the temperature difference output by the temperature difference sensor 170, and the humidity value output by the humidity sensor 180, and generate a defogging control command based on the fusion of multi-source information.

[0120] Based on multi-information fusion, the following rules can be set: When the humidity value is below the first humidity threshold and the light transmittance is above the first light transmittance threshold, it is determined to be a fog-free state, and defogging is not initiated; when the humidity value reaches the first humidity threshold but the light transmittance is still above the first light transmittance threshold and the temperature difference is less than the preset temperature threshold, it is determined to be a low-risk state, and low-amplitude continuous waves are used for sustained defogging; when the light transmittance is below the first light transmittance threshold or the temperature difference is greater than the preset temperature threshold and the humidity value reaches the second humidity threshold, it is determined to be a medium-risk state, and medium-amplitude continuous waves superimposed with pulse waves are used for defogging; when the light transmittance is below the second light transmittance threshold, the temperature difference is greater than the preset temperature threshold, and the humidity value reaches the third humidity threshold, it is determined to be a high-risk state, and high-amplitude pulse waves are used for rapid defogging. The first, second, and third humidity thresholds increase sequentially, while the first and second light transmittance thresholds decrease sequentially, forming a graded response mechanism.

[0121] Therefore, in this embodiment, by fusing the output information of the photosensor 160, the temperature difference sensor 170, and the humidity sensor 180, the fogging risk and defogging requirements can be comprehensively assessed from multiple dimensions, including optical state, temperature conditions, and humidity conditions. This can alleviate the misjudgment or missed judgment of a single sensor in special scenarios. Furthermore, the graded response mechanism can optimize energy consumption and extend the device's battery life while ensuring the defogging effect.

[0122] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0123] The near-eye display device and defogging control method provided in the embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the technical solutions and core ideas of this application. Those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A near-eye display device, characterized in that, The near-eye display device includes: The device body includes a frame and a lens disposed in the frame; Multiple piezoelectric ceramic sheets are disposed on opposite sides of the lens; multiple piezoelectric ceramic sheets located on the same side of the lens are spaced apart along the edge of the lens; A drive module is disposed inside the device body; the drive module is electrically connected to a plurality of piezoelectric ceramic sheets respectively, and the drive module is used to output a drive voltage to drive the plurality of piezoelectric ceramic sheets to vibrate, thereby causing the lens to vibrate.

2. The near-eye display device according to claim 1, characterized in that, The piezoelectric ceramic sheets located on the same side of the lens are arranged in at least one column along the edge of the lens.

3. The near-eye display device according to claim 1, characterized in that, A buffer structure layer is provided between the piezoelectric ceramic sheet and the lens.

4. The near-eye display device according to claim 3, characterized in that, The buffer structure layer is a transparent structure layer.

5. The near-eye display device according to claim 1, characterized in that, The driving voltage includes a first driving voltage and a second driving voltage. The waveform of the first driving voltage is a continuous waveform, and the waveform of the second driving voltage is a pulse waveform.

6. The near-eye display device according to claim 5, characterized in that, The frequency of the first driving voltage is less than the frequency of the second driving voltage.

7. The near-eye display device according to claim 5 or 6, characterized in that, The waveform amplitude of the first driving voltage is smaller than that of the second driving voltage.

8. The near-eye display device according to claim 1, characterized in that, The driving module includes multiple driving units, each driving unit being configured in a one-to-one correspondence with a multiple piezoelectric ceramic sheet, and each driving unit being used to drive the corresponding piezoelectric ceramic sheet.

9. The near-eye display device according to claim 8, characterized in that, The piezoelectric ceramic sheet includes a first electrode layer, a piezoelectric thin film layer, and a second electrode layer, wherein the piezoelectric thin film layer is located between the first electrode layer and the second electrode layer. Each of the piezoelectric ceramic sheets has a first electrode layer comprising an electrode sheet having a first electrode line for electrical connection to the corresponding driving unit. The second electrode layer has at least one second electrode line leading out, which is used for grounding.

10. The near-eye display device according to claim 9, characterized in that, The driving unit includes at least one driving branch, and the driving branch includes: A switching transistor, wherein the first terminal of the switching transistor is used to receive a control signal, the second terminal of the switching transistor is used to receive a power supply voltage, and the third terminal of the switching transistor is used to be electrically connected to the first electrode line and to output a driving voltage to the corresponding electrode plate; An energy storage capacitor, one end of which is connected to the third terminal of the switching transistor, and the other end of which is grounded.

11. The near-eye display device according to claim 1, characterized in that, The near-eye display device also includes: A photosensitive sensor is disposed at the periphery of the lens. The photosensitive sensor is used to detect the light intensity transmitted through the lens and output a light intensity detection signal.

12. The near-eye display device according to claim 1, characterized in that, The near-eye display device also includes: A temperature difference sensor is disposed at the periphery of the lens, and the temperature difference sensor is used to detect the temperature difference between the lens and the current environment.

13. The near-eye display device according to claim 1, characterized in that, The near-eye display device also includes: A humidity sensor is disposed around the periphery of the lens and is used to detect the humidity value of the environment in which the lens is located.

14. A defogging control method, characterized in that, The defogging control method is applied in the near-eye display device as described in any one of claims 1-13, and the defogging control method includes: Obtain a defogging control command and determine the driving parameters of the drive module based on the defogging control command. The driving parameters include one or more of the following: driving voltage, driving current, or driving frequency. The drive module controls the vibration of the piezoelectric ceramic sheet according to the drive parameters.

15. The defogging control method according to claim 14, characterized in that, The driving parameters include at least one of the following: the waveform type of the driving voltage, the duty cycle, the pulse width, the output duration, the interval period, and the driving phase relationship between the multiple piezoelectric ceramic sheets.

16. The defogging control method according to claim 14, characterized in that, The defogging control method further includes: Acquire the light intensity detection signal output by the photosensitive sensor; The transmittance of the lens is determined based on the light intensity detection signal, and the defogging control command is triggered when the transmittance is less than a preset threshold.

17. The defogging control method according to claim 14, characterized in that, The defogging control method further includes: Obtain the temperature difference output by the temperature difference sensor; When the temperature difference exceeds a preset temperature threshold, the defogging control command is triggered.

18. The defogging control method according to claim 14, characterized in that, The defogging control method further includes: Obtain the humidity value from the humidity sensor; When the humidity value reaches the preset humidity threshold, the defogging control command is triggered.

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