Display device

Abstract

This application provides a display device belonging to the field of naked-eye stereoscopic display technology, including a backlight module, a beam deflection element, a display panel, a data acquisition unit, and a control unit. The backlight module outputs a parallel illumination beam, and the data acquisition unit acquires the position of the user's eye and outputs a detection signal. The beam deflection element contains two immiscible conductive and non-conductive liquids with different refractive indices, which adjust the beam emission direction without obstruction by relying on electrowetting effect. The control unit adjusts the beam direction according to the user's eye detection signal, drives the panel to alternately output left and right parallax images at a preset frequency, and can also switch to a planar display mode. This application eliminates the light-shielding grating structure, resulting in high light energy utilization, fast device response speed, and the ability to adjust the light path in real time to follow the user's eye position, reducing viewing dizziness. It is compatible with various backlights and display panels.

Description

Technical Field

[0001] This application relates to the field of display technology, and more specifically to a display device. Background Technology

[0002] Currently, the mainstream naked-eye 3D displays on the market mainly adopt two structures: parallax gratings and fixed cylindrical lenses. Parallax gratings rely on light-blocking areas to separate light from the left and right eyes, which directly loses more than half of the backlight brightness, resulting in low screen luminous efficiency and high device power consumption. Fixed cylindrical lenses do not have light-blocking loss, but the lens optical parameters cannot be changed after leaving the factory, and can only be matched to a fixed viewing distance. Even a slight shift in the user's head will cause image blurring and loss of stereoscopic effect.

[0003] Most existing glasses-free display devices using electrowetting structures can only achieve fixed-zone optical path adjustment, and the adjustable beam angle range is narrow, which cannot adapt to scenarios with a wide range of human eye movement. At the same time, the related devices do not have a matching closed-loop control device for human eye position detection, and can only pre-set fixed optical path parameters, and cannot dynamically correct the beam angle according to the real-time human eye coordinates.

[0004] Traditional glasses-free 3D display devices struggle to freely switch between 2D and 3D display modes. When a 2D image is displayed, the light path still causes beam splitting and deflection, resulting in uneven brightness and blurred edges. Existing devices lack an independent light path reset structure, requiring complex software adjustments when switching to a 2D image. Furthermore, most traditional glasses-free devices can only be paired with a single backlight and LCD screen, making them incompatible with laser collimated backlighting, edge-lit backlighting, and new display panels such as organic light-emitting and micro-light-emitting panels. Summary of the Invention

[0005] This application provides a display device that has the advantages of high brightness, dynamic adaptation to viewing position, and reduced visual fatigue.

[0006] The display device provided in this application includes a backlight module, a beam deflection element, a display panel, a data acquisition unit, and a control unit: the beam deflection element is disposed between the backlight module and the display panel, and the control unit is connected to the backlight module, the beam deflection element, the display panel, and the data acquisition unit respectively; The backlight module is used to output a parallel illumination beam; The acquisition unit is used to detect the position of the human eye and output the detection signal of the human eye position; The control unit is configured to control the beam deflection element to guide the illumination beam to the viewing area corresponding to the human eye position according to the detection signal, and to control the display panel to alternately display different parallax views at a preset frequency, wherein the preset frequency is greater than or equal to the set screen alternation frequency; The beam deflection element comprises at least two immiscible liquids with different refractive indices, including conductive and non-conductive liquids. The beam deflection element is used to adjust the emission direction of the illumination beam in a non-obstructive manner, and to project images onto the viewing area in a time-division manner in conjunction with the display panel.

[0007] In summary, the display device provided in this application outputs regular parallel light through a backlight module, ensuring the accuracy of the beam deflection element angle adjustment. The acquisition unit captures the human eye position in real time and outputs detection signals, providing data support for dynamic light path adjustment. The beam deflection element uses two immiscible liquids with different refractive indices, one conductive and one non-conductive. Unobstructed light path adjustment is achieved by relying on changes in the liquid interface morphology, eliminating the need for a light-blocking grating and supporting high-frequency time-sharing image alternation. The control unit and the human eye acquisition unit form a closed-loop control system, continuously updating the driving voltage based on the real-time position of the human eye to dynamically adjust the beam projection area. No image crosstalk occurs even when the human head moves, effectively alleviating viewing dizziness. Furthermore, by outputting a constant voltage to keep the liquid interface flat, a uniform light-emitting planar display mode is switched. This allows compatibility with various backlight structures and display panels. The integrated hardware architecture reduces software dependence, while simultaneously achieving high brightness, dynamic human eye adaptation, fast response, and multi-mode compatibility. Attached Figure Description

[0008] The present application will be further described below with reference to the accompanying drawings. It should be noted that the accompanying drawings described below are merely for explaining some embodiments of the present application. Those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0009] Figure 1 A schematic diagram of a display device provided for an embodiment of this application.

[0010] Figure 2 This is a schematic diagram of the structure of the display device in the embodiments of this application.

[0011] Figure 3 This is a schematic diagram illustrating the structure and working principle of the wetting adjustable prism unit in the embodiments of this application.

[0012] Figure 4 This is a schematic diagram showing the relationship between the beam deflection angle and the applied voltage in an embodiment of this application.

[0013] Figure 5 This is a schematic diagram of the dynamic eye-tracking closed-loop control in the embodiments of this application. Detailed Implementation

[0014] 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.

[0015] The terms "first," "second," etc., used in this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, apparatus, product, or device that includes a series of steps or modules is not limited to the listed steps or modules, but may optionally include steps or modules not listed, or may optionally include other steps or modules inherent to these processes, methods, products, or devices.

[0016] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily imply that all embodiments are the same, nor are they independent or alternative embodiments mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0017] This application provides a display device, which includes, but is not limited to, the following embodiments and combinations thereof.

[0018] In one embodiment, Figure 1 A schematic diagram of a display device provided for an embodiment of this application, as shown below. Figure 1 As shown, the display device 100 includes a backlight module 101, a beam deflection element 102, a display panel 103, a data acquisition unit 104, and a control unit 105. The beam deflection element 102 is disposed between the backlight module 101 and the display panel 103, and the control unit 105 is connected to the backlight module 101, the beam deflection element 102, the display panel 103, and the data acquisition unit 104.

[0019] Backlight module 101 is used to output a parallel illumination beam.

[0020] The acquisition unit 104 is used to detect the position of the human eye and output the detection signal of the human eye position.

[0021] The control unit 105 is used to control the beam deflection element 102 to guide the illumination beam to the viewing area corresponding to the human eye position according to the detection signal, and to control the display panel 103 to alternately display different parallax views at a preset frequency, wherein the preset frequency is greater than or equal to the set screen alternation frequency.

[0022] The beam deflection element 102 includes at least two immiscible liquids with different refractive indices. The at least two liquids include conductive liquids and non-conductive liquids. The beam deflection element 102 is used to adjust the emission direction of the illumination beam in a non-obstructive manner and to project images onto the viewing area in a time-division manner in conjunction with the display panel 103.

[0023] The display device 100 of this embodiment is designed to achieve glasses-free stereoscopic display. It includes a backlight module 101, a beam deflection element 102, a display panel 103, a data acquisition unit 104, and a control unit 105. The beam deflection element 102 is strategically positioned between the backlight module 101 and the display panel 103 to regulate the beam emitted by the backlight module 101, which is then displayed as an image by the display panel 103. The control unit 105 is electrically connected to the backlight module 101, the beam deflection element 102, the display panel 103, and the data acquisition unit 104 to coordinate and control the entire display process.

[0024] The backlight module 101 provides an illumination beam. As one implementation, the backlight module 101 can employ a traditional fluorescent tube or light-emitting diode array, using optical structures such as diffusers and light guides to uniformly output the light. Alternatively, the backlight module 101 can use a light source with specific collimation capabilities, for example, by using an optical lens to initially collimate the light, thereby outputting a parallel illumination beam with a low divergence angle. Specifically, the backlight module 101 outputs a parallel illumination beam with a specific directionality to ensure that the beam deflection element 102 can effectively control it. The parallel illumination beam allows the light to exit in an approximately parallel state with a low divergence angle, which facilitates precise directional control by the beam deflection element 102, thereby accurately guiding the light to the viewing area.

[0025] The acquisition unit 104 detects the viewer's eye position and generates a corresponding detection signal. For example, the acquisition unit 104 can employ a visible light image recognition-based scheme, capturing the viewer's facial image using a regular camera and analyzing eye features in the image using image processing algorithms to estimate the spatial position of the eyes. Alternatively, the acquisition unit 104 can employ a distance sensor-based scheme, measuring the distance between the viewer and the display device 100 by emitting and receiving ultrasonic waves or lasers, and inferring the approximate position of the eyes by combining this with a preset head model. Specifically, the acquisition unit 104 acquires the viewer's eye position information in real time, detects the spatial coordinates of the eyes using optical or image processing techniques, and converts the position information into a detection signal that can be processed by the control unit 105.

[0026] The control unit 105 executes a series of control operations based on the detection signal output by the acquisition unit 104. Specifically, the control unit 105 is configured to calculate the viewing area corresponding to the human eye position based on the detection signal, and control the beam deflection element 102 to precisely guide the illumination beam to the viewing area. Simultaneously, the control unit 105 also controls the display panel 103 to alternately display different parallax views at a preset frequency. The preset frequency is set to be greater than or equal to a set image alternation frequency to ensure that the viewer can perceive a smooth stereoscopic visual effect. For example, the control unit 105 can calculate the angle at which the beam needs to be deflected based on the human eye position, and then output a corresponding electrical signal to the beam deflection element 102. At the same time, the control unit 105 sends commands to the display panel 103 according to a preset timing sequence, causing it to quickly switch between the left-eye and right-eye views in a very short time. The control unit 105 receives the detection signal from the acquisition unit 104 and calculates the required beam deflection angle based on this signal. Simultaneously, the control unit 105 coordinates the operating timing of the backlight module 101, the beam deflection element 102, and the display panel 103 to ensure that beam deflection and image display are synchronized. The parallax view can be an image with subtle visual differences prepared for each of the viewer's different eyes (e.g., left and right eyes). By projecting the corresponding parallax views to the viewer's left and right eyes respectively, the human brain can perceive stereoscopic depth information, thus creating a naked-eye stereoscopic display effect.

[0027] The beam deflection element 102 comprises at least two immiscible liquids with different refractive indices, wherein at least one liquid is conductive and the other is non-conductive. For example, the beam deflection element 102 can be constructed from a transparent cavity filled with both water and oil. By applying an electric field outside the cavity, the shape of the interface between the water and oil can be altered, thereby deflecting the light passing through this interface. The beam deflection element 102 adjusts the emission direction of the illumination beam in a non-obstructive manner. When changing the beam path, it does not create viewpoint separation through physical obstruction or absorption of light, thus improving light energy utilization efficiency. In conjunction with the display panel 103, the image is projected onto the viewing area in a time-division manner. That is, when the display panel 103 displays the left-eye view, the beam deflection element 102 guides the beam to the left-eye viewing area; when the display panel 103 displays the right-eye view, the beam deflection element 102 guides the beam to the right-eye viewing area, thereby achieving naked-eye stereoscopic display. The beam deflection element 102 directionally adjusts the incident illumination beam by electronically altering the optical properties of its internal liquid, thereby achieving precise control over the beam's exit direction. This adjustment process is performed in a non-obstructive manner. Immiscible liquids with different refractive indices can serve as the basic materials for beam control by the beam deflection element 102, including conductive and non-conductive liquids. By applying an electric field, the morphology of the interface between the two liquids is changed, thus altering the beam's propagation path. The non-obstructive method allows the beam deflection element 102 to separate the viewpoint without physically blocking or absorbing light when adjusting the illumination beam direction, effectively improving backlight utilization and thus enhancing display brightness. Time-division projection allows the display panel 103 to alternately display different parallax views within extremely short time intervals. This operation is synchronized with the beam guidance of the beam deflection element 102, ensuring that at a specific time, only the parallax view corresponding to the eye is projected onto the viewing area.

[0028] The display device 100 in this embodiment achieves unobstructed dynamic adjustment of the illumination beam's emission direction by employing a liquid-electro-controlled beam deflection element 102, effectively improving backlight utilization and display brightness. Combined with alternating display of human eye position detection and high-frequency parallax views, it can dynamically adapt to the viewer's head movements, providing a stable stereoscopic visual experience.

[0029] In some embodiments of this application, the key challenge to improving the naked-eye stereoscopic display effect is how to accurately convert the human eye position information into the specific control parameters required for beam deflection and ensure that the beam deflection element 102 can respond quickly and accurately to achieve precise beam orientation.

[0030] Based on this, in one embodiment, the control unit 105 is also configured to determine the beam target deflection angle of the adapted viewing area based on the detection signal, output a driving voltage according to the target deflection angle, and control the display panel 103 to switch parallax views in a timing sequence with a preset frequency. The beam deflection element 102 is also used to change the interface morphology of at least two liquids based on the driving voltage, so as to adjust the emission angle of the parallel illumination beam without obstruction, and to project the image to the corresponding viewing area in turn with the display panel 103.

[0031] Specifically, after receiving the eye position detection signal output by the acquisition unit 104, the control unit 105 no longer simply controls the beam deflection element 102, but performs more precise calculations and control. The control unit 105 can internally preset a mapping table or algorithm model, which can calculate the horizontal and vertical angles that the illumination beam needs to be deflected, i.e., the "beam target deflection angle," based on the spatial coordinates of the human eye (e.g., the X, Y, and Z coordinates obtained through an infrared camera and image processing module). The calculation process involves geometric optics principles, using trigonometric functions or vector operations to determine the precise emission direction of the beam by analyzing the relative positional relationship between the display panel 103, the beam deflection element 102, and the human eye. For example, when the human eye moves to the left, the control unit 105 calculates a corresponding target angle for leftward deflection. Once the beam target deflection angle is determined, the control unit 105 converts this angle into a specific "driving voltage" value based on the specific optical characteristics of the beam deflection element 102 (e.g., the voltage-angle response curve of the electrowetting effect). The conversion can be achieved by consulting a pre-stored calibration data sheet or by calculating a model in real time, ensuring that the driving voltage accurately causes the beam deflection element 102 to reach the required beam deflection angle. Furthermore, the control unit 105 includes a timing generator that generates a synchronization signal at a preset frequency (e.g., 120Hz or higher). This signal is used to trigger the display panel 103 to switch to the next parallax view (e.g., alternating between left-eye and right-eye views) and also to synchronize the response of the beam deflection element 102, ensuring that the beam deflects to the correct viewing area at the correct time.

[0032] After receiving the driving voltage output from the control unit 105, the conductive and non-conductive liquids inside the beam deflection element 102 undergo an electrowetting effect, thereby changing their interface morphology. When voltage is applied to the electrodes of the beam deflection element 102, the surface tension between the conductive liquid and the electrodes changes, causing deformation of the liquid interface. For example, in an electrowetting prism, the interface tilts; in an electrowetting lens, the interface bends. The change in interface morphology directly affects the refraction path of the parallel illumination beam passing through the liquid, thereby precisely adjusting its exit angle. Since beam deflection is achieved by changing the interface morphology of the transparent liquid, rather than by mechanical obstruction or moving solid components, the entire process is optically transparent and does not obstruct the beam, thus ensuring high transmittance and lossless beam deflection. The response speed of the beam deflection element 102 is fast enough to switch parallax views in accordance with the preset frequency of the display panel 103. For example, when the display panel 103 displays the left-eye view, the beam deflection element 102 quickly deflects the beam to the left-eye viewing area; when the display panel 103 switches to the right-eye view, the beam deflection element 102 quickly deflects the beam to the right-eye viewing area.

[0033] In this application, the control unit 105 can accurately calculate the beam deflection angle required to adapt to the viewing area based on the acquired eye position detection signal, and generate a precise driving voltage accordingly. Upon receiving the driving voltage, the beam deflection element 102 can quickly and unobstructedly change the interface morphology of its internal liquid, thereby achieving precise adjustment of the exit angle of the parallel illumination beam. This ensures that the illumination beam can be accurately and promptly guided to the viewing area corresponding to the eye position, and achieves high synchronization with the parallax view switching of the display panel 103, greatly improving the viewing experience of the naked-eye stereoscopic display, allowing users to continuously obtain clear and stable stereoscopic images even while moving.

[0034] In some embodiments of this application, how to accurately, efficiently and stably control the morphology of the liquid interface so as to enable it to effectively deflect the parallel illumination beam and ensure that the beam can be accurately projected onto the dynamically changing viewing area of ​​the human eye is a technical problem that needs to be solved.

[0035] Based on this, in one embodiment, the beam deflection element 102 includes an electrowetting adjustable prism array; the electrowetting adjustable prism array includes a transparent cavity and an electrode structure, the electrode structure being disposed on the sidewall of the transparent cavity; A transparent cavity for containing at least two liquids; An electrode structure is used to apply a driving voltage to change the tilt angle of the interface between at least two liquids, causing a prism-like deflection of the parallel illumination beam.

[0036] The electrowetting tunable prism array is a micro-optical device that deflects a light beam based on the electrowetting effect. It utilizes an electric field to alter the interfacial tension between a liquid and a solid surface, thereby controlling the shape and position of the liquid. When a voltage is applied, the contact angle between the conductive liquid and the electrode changes, causing the liquid interface to tilt, forming a variable optical prism. This prism quickly and precisely adjusts the exit direction of the incident light beam in a non-mechanical, unobstructed manner, effectively deflecting a parallel illumination beam. A transparent cavity serves as the physical carrier of the electrowetting tunable prism array, safely and stably containing at least two immiscible liquids with different refractive indices. The cavity is made of optically transparent materials, such as glass, quartz, or transparent polymers, to ensure lossless transmission of the parallel illumination beam. The cavity's geometry and dimensions are precisely designed to accommodate the deformation requirements of the liquid interface and ensure the optical quality of the beam during internal transmission. The electrode structure is a key component for realizing the electrowetting effect, used to apply a driving voltage to the liquid within the cavity. The electrodes are made of conductive materials and are precisely patterned. By placing the electrode structure on the sidewall of the transparent cavity, rather than directly in the optical path, it is possible to effectively avoid the electrodes blocking and scattering the light beam, thereby ensuring the unobstructed adjustment characteristics and high optical transmittance of the beam deflection element 102. The sidewall configuration allows an electric field to form inside the liquid, precisely controlling the tilt angle of the liquid interface while maintaining an unobstructed optical path. Once the control unit 105 determines the desired beam deflection angle based on the viewer's position, it outputs a corresponding driving voltage to the electrode structure. This driving voltage, through the electrowetting effect, precisely changes the tilt angle of the interface between the conductive and non-conductive liquids.

[0037] This application employs an electrowetting adjustable prism array as the beam deflection element 102, with its electrode structure disposed on the sidewall of a transparent cavity. This enables precise, rapid, and unobstructed adjustment of the emission direction of the parallel illumination beam. Specifically, the driving voltage applied by the control unit 105 can directly act on the electrode structure, thereby changing the tilt angle of at least two liquid interfaces through the electrowetting effect, causing the parallel illumination beam to undergo controllable prism-like deflection. This not only has a fast response speed, meeting the timing requirements of the display panel 103 alternately displaying different parallax views at a preset frequency, but also avoids the problems of large size, slow response, and high light loss caused by traditional mechanical or obstructive deflection due to its non-mechanical and unobstructed characteristics.

[0038] In some embodiments of this application, the contact state between the conductive liquid and the inner wall of the transparent cavity may not be stable enough, making it difficult to precisely control and maintain the tilt angle of the liquid interface, thereby affecting the stability and accuracy of the illumination beam deflection.

[0039] Accordingly, in one embodiment, the beam deflection element 102 further includes a hydrophobic insulating layer; the hydrophobic insulating layer is disposed on the inner wall of the transparent cavity; A hydrophobic insulating layer is used to regulate the contact state between the conductive liquid and the inner wall, and to stabilize the tilt angle of the interface formed by at least two liquids.

[0040] Specifically, the hydrophobic insulating layer is a thin film of insulating material with hydrophobic properties. This layer is uniformly deposited on the inner wall of the transparent cavity through processes such as coating and deposition, ensuring direct contact between the layer and the liquid inside the cavity. The main function of the hydrophobic insulating layer is to alter the surface wetting characteristics between the conductive liquid and the inner wall of the transparent cavity. Without an applied driving voltage, the hydrophobic insulating layer allows the conductive liquid to form a large contact angle on the inner wall, thereby reducing its contact area and providing a stable initial interface state. When a driving voltage is applied to the electrode structure, the electrowetting effect changes the contact angle between the conductive liquid and the hydrophobic insulating layer, thus altering the tilt angle of the interface between the conductive and non-conductive liquids. The presence of the hydrophobic insulating layer provides a uniform and predictable surface environment for the electrowetting effect, effectively avoiding liquid interface instability caused by surface defects or inhomogeneities in the cavity material. By controlling the contact state between the conductive liquid and the inner wall, the hydrophobic insulating layer ensures that, after applying a specific driving voltage, the liquid interface can be precisely and stably maintained at the required tilt angle, thereby achieving stable control of the exit angle of the parallel illumination beam.

[0041] This application effectively controls the contact state between the conductive liquid and the inner wall by setting a hydrophobic insulating layer on the inner wall of the transparent cavity. The hydrophobic insulating layer provides a stable interface environment, which allows the interface formed by the conductive liquid and the non-conductive liquid to more accurately and stably reach and maintain the required tilt angle when a driving voltage is applied. This avoids problems such as inaccurate deflection or jitter of the illumination beam caused by the instability of the liquid interface, thereby ensuring that the beam deflection element 102 can guide the illumination beam to the viewing area corresponding to the human eye position with higher accuracy and stability, thus improving the viewing experience of naked-eye stereoscopic display.

[0042] In some embodiments of this application, relying solely on angle deflection may be insufficient to meet the need for more precise control of the light field. For example, when it is necessary to dynamically adjust the convergence or divergence of the light beam according to the viewing distance, a single angle deflection may be inadequate, thereby affecting the depth of field and viewing comfort of naked-eye 3D displays.

[0043] Based on this, in one embodiment, the beam deflection element 102 includes an electrowetting adjustable lens array; the electrowetting adjustable lens array includes at least two independent lens units, each containing a conductive liquid and a non-conductive liquid; the electrowetting adjustable lens array is used to change the interface curvature of at least two liquids based on a driving voltage to control the convergence and angle deflection of the parallel illumination beam.

[0044] Specifically, an electrowetting adjustable lens array is a micro-optical device that dynamically changes the shape of a liquid interface using the electrowetting effect, thereby adjusting optical properties. As a beam deflection element 102, it not only achieves beam angle deflection but also provides the ability to converge or diverge beams. Compared to elements that only provide angle deflection, its ability to control the light field is more precise and comprehensive. The array typically consists of multiple independent lens units, each of which can be independently controlled by applying an electric field to the liquid interface to change its curvature.

[0045] At least two independent lens units refer to the modular structure of an electrowetting adjustable lens array. Each lens unit is a self-contained optical adjustment unit that provides localized and precise control over the light field, enabling differentiated processing of the light beam in different regions based on the user's eye position or multi-viewpoint requirements. Each unit typically includes a cavity, electrodes, and a liquid contained within them. By applying different driving voltages to different units, independent optical control of the light beam in each region of the array can be achieved.

[0046] Each lens unit contains both a conductive and a non-conductive liquid, forming the basis for optical adjustment through electrowetting. The two liquids are immiscible and have different refractive indices. Under the influence of an electric field, the interface between the conductive and non-conductive liquids deforms, thereby altering the optical properties of the lens unit. The conductive liquid is typically an aqueous solution (such as salt water), while the non-conductive liquid is typically oil. They are injected into the cavity of the lens unit, forming a stable interface. By selecting liquids with suitable refractive index differences, an ideal range of optical adjustment can be obtained.

[0047] Electrowetting adjustable lens arrays utilize a driving voltage to alter the curvature of the interface between at least two liquids, thereby controlling the convergence and angular deflection of a parallel illumination beam. By precisely controlling the driving voltage, the curvature of the liquid interface can be dynamically changed, thus achieving comprehensive control over the convergence (focusing), divergence (defocusing), and angular deflection (direction) of the incident parallel illumination beam. When a voltage is applied, the electric field alters the wettability of the conductive liquid on the electrode surface, causing a change in the shape of the liquid interface, i.e., a change in curvature. For example, by applying different voltages to different electrodes of the lens unit, the interface can exhibit different tilt angles or curvatures, thereby achieving precise beam guidance and focusing / defocusing.

[0048] This application overcomes the limitations of simply performing angle deflection by introducing an electrowetting adjustable lens array as the beam deflection element 102. By changing the interface curvature of at least two liquids based on the driving voltage, the lens array not only achieves angle deflection of the parallel illumination beam, but more importantly, it also enables the convergence or divergence control of the beam. The display device 100 can more precisely adjust the light field according to the user's eye position and viewing needs. For example, it can dynamically adjust the beam convergence based on the viewing distance, ensuring that the user receives a clear, focused parallax image at different distances, effectively improving the depth and comfort of naked-eye 3D displays. Furthermore, the collaborative operation of multiple independent lens units makes light field control more flexible, providing customized light distribution for viewers from different perspectives, thereby optimizing multi-viewpoint 3D display effects and providing a wider free viewing area.

[0049] In some embodiments of this application, accurately and in real-time acquiring human eye position information and converting it into signals usable by the control unit 105 is a key challenge in achieving glasses-free stereoscopic display effects. Traditional detection methods may suffer from insufficient accuracy, slow response speed, or sensitivity to ambient light, thus affecting the viewing experience.

[0050] Based on this, in one embodiment, the acquisition unit 104 includes an infrared camera and an image processing module; the infrared camera is connected to the image processing module; the infrared camera is used to acquire regional images of the viewing area where the human eye is located; the image processing module is used to parse the regional images, obtain the spatial coordinates of the human eye, and generate a detection signal based on the spatial coordinates.

[0051] The acquisition unit 104 is a key component for acquiring human eye position information. It is specifically implemented as a combination of an infrared camera and an image processing module, aiming to leverage the advantages of infrared technology. The infrared camera can emit and receive infrared light, operates stably under different ambient lighting conditions, and is not easily affected by visible light interference, thus improving the robustness of human eye detection. The image processing module analyzes and processes the image data captured by the infrared camera to extract effective human eye position information. The two are connected via electrical signals or a data bus to ensure real-time and accurate data transmission.

[0052] Infrared cameras work by emitting infrared light and receiving it reflected from the human eye. The human eye has specific reflective properties for infrared light; for example, the pupil exhibits a "bright pupil" or "dark pupil" effect under infrared light, allowing infrared cameras to clearly capture the characteristics of the human eye. By acquiring images of the viewing area, infrared cameras can obtain raw visual data containing human eye features, avoiding direct contact with the eye, making them non-invasive, and adaptable to different users wearing glasses, among other things.

[0053] After receiving the regional image captured by the infrared camera, the image processing module analyzes it using a series of image processing algorithms, including but not limited to: image preprocessing (such as noise reduction and enhancement), feature point detection (such as pupils, corners of the eyes, etc.), human eye region segmentation, and calculation of three-dimensional spatial coordinates based on binocular vision or monocular models. Through these algorithms, the image processing module can accurately determine the three-dimensional spatial position of the human eye in front of the display device 100, i.e., the spatial coordinates of the human eye. Subsequently, the spatial coordinate information is encapsulated into standardized detection signals for use by the control unit 105 to guide the beam deflection element 102 and the display panel 103 to make corresponding adjustments.

[0054] In this application, the acquisition unit 104 is specifically implemented as a combination of an infrared camera and an image processing module. This application overcomes the limitations of traditional human eye detection methods in terms of accuracy, real-time performance, and environmental adaptability. The infrared camera can stably and non-invasively acquire images of the human eye area under different lighting conditions, providing high-quality raw data for subsequent processing. The image processing module can accurately analyze the image, obtain the three-dimensional spatial coordinates of the human eye, and convert them into a detection signal recognizable by the control unit 105. The accurate and real-time detection signal enables the control unit 105 to more accurately control the beam deflection element 102 to guide the illumination beam to the viewing area corresponding to the human eye position, and simultaneously control the display panel 103 to alternately display different parallax views. Therefore, the display device 100 can achieve a more stable and comfortable naked-eye stereoscopic display effect, improving the user's viewing experience. Especially when the user's head moves, the device can quickly respond and adjust the displayed content to ensure the continuity and accuracy of the stereoscopic image.

[0055] In some embodiments of this application, the position of the human eye is not always fixed. The user may move their head or eyes slightly. If the beam deflection angle cannot respond to the position change in time, the beam projected onto the human eye may deviate from the viewing area, affecting the stability of the stereoscopic display effect and the viewing experience.

[0056] Based on this, in one embodiment, the control unit 105 is also used to re-determine the beam target deflection angle adapted to the human eye position based on the detection signal after each preset number of screen alternation cycles, and update the driving voltage to control the beam deflection element 102 to dynamically adjust the emission direction of the illumination beam as the human eye moves.

[0057] Specifically, the screen alternation cycle refers to the time required for the display panel 103 to complete one switch between different parallax views. For example, if the display panel 103 alternates between displaying the left and right eye parallax views at a frequency of 120Hz, then one screen alternation cycle is 1 / 120th of a second. With a preset number of screen alternation cycles, the control unit 105 does not recalculate and adjust in every screen alternation cycle, but rather performs this in a configurable, relatively long cycle. This effectively reduces the computational load on the control unit 105 and the frequent adjustments to the beam deflection element 102 while ensuring device responsiveness, thereby extending device lifespan and improving device stability. The preset number can be flexibly set according to the actual application scenario, the expected range of human eye movement speed, and the device's response speed requirements. The control unit 105 periodically acquires the latest detection signal, which contains precise information about the current human eye position. Based on the latest position data, the control unit 105 recalculates the most suitable beam target deflection angle for the current human eye position, which may involve complex geometric optics calculations to ensure that the illumination beam is accurately projected onto the pupil area of ​​the human eye, thereby ensuring that the user can clearly see the stereoscopic image. Once a new beam deflection angle is determined, the control unit 105 converts this angle into the driving voltage required by the beam deflection element 102 according to a preset mapping relationship or control algorithm. The driving voltage is immediately applied to the beam deflection element 102, causing a change in the morphology of the liquid interface within it, thereby deflecting the illumination beam. Through the aforementioned periodic detection, calculation, and voltage update, the beam deflection element 102 can continuously adjust the emission direction of the illumination beam in real time. This ensures that even with slight movements in the human eye's position, the illumination beam can always accurately track the eye, projecting the correct parallax image into the corresponding eye, thus maintaining a stable glasses-free stereoscopic display effect.

[0058] The display device 100 in this application overcomes the challenge of dynamic changes in the human eye's position. Instead of statically determining the beam deflection angle, the control unit 105 periodically reassesses the human eye's position at a preset frequency and dynamically updates the beam target deflection angle and driving voltage accordingly. This allows the beam deflection element 102 to follow the human eye's position movement in real time and accurately, continuously adjusting the emission direction of the illumination beam. This ensures the illumination beam is always accurately projected onto the viewing area corresponding to the human eye, improving the stability and robustness of the naked-eye stereoscopic display effect. Even if the viewer moves within a certain range, a clear and stable stereoscopic image can be continuously obtained, thereby enhancing the user's viewing experience and avoiding problems such as loss of stereoscopic effect or image blurring caused by human eye movement.

[0059] In some embodiments of this application, users may need to view traditional planar images. If the stereoscopic display mode is maintained at this time, it may not only cause unnecessary energy consumption, but also affect the viewing experience of planar images due to the alternation of parallax views, thus reducing the versatility of the display device 100.

[0060] Based on this, in one embodiment, the control unit 105 is also used to output zero voltage or constant voltage to the beam deflection element 102 in the display control mode of the planar image, so that the interface between the conductive liquid and the non-conductive liquid remains flat, the parallel illumination beam is emitted uniformly and vertically, and the display panel 103 is controlled to continuously output a single planar image and the alternation of parallax view is turned off.

[0061] Specifically, in the planar image display control mode, the control unit 105 outputs zero voltage or a constant voltage to the beam deflection element 102. Outputting zero voltage or a constant voltage to the beam deflection element 102 means that, in the planar image display mode, the control unit 105 does not apply a driving voltage to the beam deflection element 102 (i.e., zero voltage), or applies a fixed voltage insufficient to cause deformation of the liquid interface (i.e., constant voltage). Both methods keep the electrowetting effect inside the beam deflection element 102 in an inactive or stable ground state, thereby ensuring that the interface between the conductive and non-conductive liquids maintains its natural flatness and does not undergo optical deflection.

[0062] Maintaining a smooth interface between conductive and non-conductive liquids is crucial for achieving uniform and perpendicular emission of parallel illumination beams. In the principle of electrowetting, when no voltage is applied or a specific constant voltage is applied, the surface tension between the liquids causes the interface to approach a state of minimum surface energy, typically manifesting as a smooth interface. For an incident parallel illumination beam, a smooth interface acts as an optical plane, preventing refraction or deflection of the beam.

[0063] The uniform vertical emission of the parallel illumination beam means that when the interface between the conductive and non-conductive liquids remains flat, the parallel illumination beam output by the backlight module 101, after passing through the beam deflection element 102, maintains the same emission direction as the incident direction, and the rays within the beam remain parallel without convergence, divergence, or deflection. This ensures that the beam can be projected onto the display panel 103 in a uniform and distortion-free manner, providing uniform backlighting for the display panel 103.

[0064] Simultaneously, the control unit 105 controls the display panel 103 to continuously output a single planar image. This means that, in planar image display mode, the control unit 105 sends a command to the display panel 103, causing it to stop alternating between parallax views and instead continuously display a single frame of static or dynamic planar image, like a traditional 2D display. This ensures that users receive a stable, flicker-free image experience when viewing 2D content.

[0065] Furthermore, the control unit 105 disables the alternation of parallax views. Disabling the alternation of parallax views is an operation corresponding to the naked-eye stereoscopic display mode. In stereoscopic display mode, the display panel 103 alternates between displaying at least two parallax views at a preset frequency. However, in planar image display mode, the control unit 105 stops sending switching commands to the display panel 103 or sets the switching frequency to zero, thereby effectively disabling the alternation of parallax views and avoiding visual interference and device overhead caused by unnecessary switching.

[0066] This application introduces a planar image display control mode into the display device 100, allowing users to flexibly switch display modes according to actual needs. In planar image display mode, the control unit 105 outputs zero voltage or a constant voltage to the beam deflection element 102, effectively maintaining the flatness of the interface between the conductive and non-conductive liquids, thereby ensuring that the parallel illumination beam is emitted uniformly and perpendicularly, avoiding unnecessary deflection and optical distortion. Simultaneously, the control unit 105 controls the display panel 103 to continuously output a single planar image and disables the alternation of parallax views, eliminating visual fatigue and energy consumption caused by the alternation of parallax views in stereoscopic display mode. This enables the display device 100 to not only provide a high-quality naked-eye stereoscopic display experience but also to offer a clear, stable, and energy-efficient display effect when viewing traditional 2D content, improving the device's practicality and user experience.

[0067] In some implementations, if the illumination beam output by the backlight module 101 is not parallel enough or has poor uniformity, it may result in the beam not being able to achieve truly uniform vertical emission in planar image display mode, thereby affecting the quality of the display and the efficiency of light energy utilization.

[0068] Based on this, in one embodiment, the backlight module 101 includes one of a laser diode with a collimating lens group, a side-lit collimated light-emitting diode backlight, and a direct-lit collimated light-emitting diode backlight; the divergence angle of the parallel illumination beam output by the laser diode with the collimating lens group is no greater than ±2 degrees; the side-lit collimated light-emitting diode backlight and the direct-lit collimated light-emitting diode backlight are used to output the parallel illumination beam.

[0069] Specifically, the backlight module 101 provides illumination in the display device 100, outputting a parallel illumination beam. To ensure high parallelism and uniformity of the beam, this application provides several implementation methods. The first method is to use a laser diode paired with a collimating lens group. Laser diodes, as light sources, have high brightness, high directionality, and a narrow spectrum, but their initial emitted beam usually has a certain divergence angle. Therefore, a collimating lens group is needed to shape the beam emitted by the laser diode, converting it into a highly parallel beam. This collimating lens group typically consists of one or more optical elements, such as aspherical lenses, cylindrical lenses, or diffractive optical elements. Through precise optical design and assembly, the emitted beam from the laser diode is effectively collected and collimated, so that the divergence angle of the output parallel illumination beam can be controlled within a range of no more than ±2 degrees, thereby ensuring extremely high parallelism. The second method is to use a side-lit collimated light-emitting diode backlight. In this structure, the light-emitting diode (LED) is usually placed on the side of the light guide plate, and light enters the light guide plate from the side. The light guide plate has microstructures (such as microprisms, scattering points, etc.) designed inside or on its surface to uniformly guide light and emit it from the front. To achieve a "collimation" effect, multiple optical films, such as diffusers and brightness enhancement films (BEF), are usually stacked on top of the light guide plate. The films work together to narrow the angular distribution of the emitted light, making it approach parallel light. The third method is to use a direct-lit collimated LED backlight. In this structure, the LED array is directly arranged below the display panel 103. To achieve collimation, an independent collimating lens (such as a total internal reflection lens) can be placed above each LED, or one or more diffusers and brightness enhancement films can be placed above the entire LED array. By precisely controlling the distance between the LED and the optical films and the characteristics of the films, the light emitted by the LEDs is homogenized and collimated, thereby outputting a parallel illumination beam. The common goal of the three backlight modules 101 is to provide a high-quality parallel illumination beam to meet the parallelism requirements of the subsequent beam deflection element 102 for the incident beam.

[0070] By employing the aforementioned specific type of backlight module 101, including a laser diode paired with a collimating lens group, a side-lit collimated LED backlight, or a direct-lit collimated LED backlight, and ensuring that its output parallel illumination beam has high parallelism (e.g., the divergence angle of the laser diode is no greater than ±2 degrees), this application can effectively solve the problems of degraded display quality and low light energy utilization efficiency caused by insufficient parallelism of the output beam of the backlight module 101 in planar image display mode. The parallel illumination beam, combined with the control unit 105's control to keep the beam deflection element 102 at a flat interface in planar image mode, ensures that the illumination beam can be emitted uniformly and vertically, thereby providing a clear, uniform, and sufficiently bright visual effect when displaying planar images.

[0071] In some implementations, if the display panel 103 cannot meet the high-frequency image switching requirements, or cannot provide high-quality image output in different display modes, it may affect the smoothness of the naked-eye stereoscopic display effect and the clarity of the planar image, thereby limiting the versatility of the display device 100 and the user experience.

[0072] Based on this, in one embodiment, the display panel 103 includes one of a liquid crystal panel, an organic light-emitting panel, and a micro light-emitting panel; the display panel 103 is used to output different parallax views in a time-division manner or continuously output a single planar image according to the timing instructions of the control unit 105.

[0073] Specifically, the display panel 103 can be a liquid crystal panel. A liquid crystal panel is a display technology that adjusts light transmittance by controlling the arrangement of liquid crystal molecules. Its implementation typically includes a liquid crystal layer, a polarizer, a color filter, and a thin-film transistor (TFT) array. To meet the demands of high-frequency parallax view switching, liquid crystal materials with faster response times (e.g., liquid crystals using advanced IPS or VA modes) and high refresh rate driving technology can be employed to ensure image updates are completed quickly and reduce ghosting.

[0074] In addition, the display panel 103 can also be an organic light-emitting panel. An organic light-emitting panel, or OLED panel, is a self-emissive display technology where each pixel emits light independently. Its implementation typically includes an organic light-emitting layer, an anode, a cathode, and a driving circuit. OLED panels offer advantages such as extremely fast response times (typically in the microsecond range), high contrast, wide viewing angles, and a wide color gamut, making them ideal for applications requiring rapid image switching and high-quality image performance.

[0075] Furthermore, the display panel 103 can also be a micro-LED panel. A micro-LED panel, typically referring to a Micro-LED panel, is a display technology that uses micron-sized LED chips as light-emitting pixels. Its implementation involves massively transferring a large number of tiny LED chips onto a driving substrate and using precise driving circuitry to achieve independent control of each pixel. Micro-LED panels offer advantages such as ultra-high brightness, ultra-high contrast, extremely fast response speed, and long lifespan, providing an exceptional display effect, and are particularly suitable for glasses-free 3D displays with extremely high display performance requirements.

[0076] Regardless of the type of display panel 103 used, it outputs different parallax views or continuously outputs a single planar image in a time-division manner according to the timing instructions of the control unit 105. The control unit 105 generates precise timing instructions and image data based on the human eye position detection signal and the preset display mode. In naked-eye stereoscopic display mode, the control unit 105 sends image data from different viewing angles to the display panel 103 at a frame alternation frequency higher than or equal to the set frequency, causing the display panel 103 to alternately display parallax views for the left and right eyes (or more viewing angles) in a very short time. In planar image display mode, the control unit 105 instructs the display panel 103 to continuously output a single planar image, ensuring stable image display. The driving circuit of the display panel 103 receives and parses the timing instructions, precisely controlling the brightness and color of each pixel, thereby achieving image output in different display modes.

[0077] By selecting a liquid crystal panel, an organic light-emitting panel, or a micro-light-emitting panel as the display panel 103, this application ensures that the display device 100 can accurately and frequently alternate between different parallax views in naked-eye stereoscopic display mode, effectively avoiding image ghosting and crosstalk, thereby improving the smoothness and immersion of stereoscopic display. Simultaneously, in planar image display mode, the display panel 103 can continuously output high-quality single-frame planar images, ensuring image clarity and color performance.

[0078] In some embodiments of this application, if the performance of the beam deflection element 102 is insufficient, such as having a limited deflection angle range, low optical transmittance, or slow response speed, it may result in a poor viewing experience for the user, restricting the user's freedom of head movement, affecting the brightness and clarity of the displayed image, and even causing image lag or blurring when the human eye position moves rapidly, thus making it difficult to provide a high-quality, smooth naked-eye stereoscopic display effect.

[0079] Based on this, in one embodiment, the adjustable deflection angle range of the beam deflection element 102 is greater than or equal to ±15 degrees, the optical transmittance is greater than or equal to 85%, and the optical response time is less than one millisecond; the beam deflection element 102 is also used to adjust the emission angle of the parallel illumination beam without obstruction, and to guide the parallel illumination beam to the viewing area corresponding to the human eye in a time-division manner, so as to realize naked-eye stereoscopic display.

[0080] Specifically, the adjustable deflection angle range of the beam deflection element 102 is greater than or equal to ±15 degrees, meaning that the element can deflect the incident parallel illumination beam by at least ±15 degrees in the horizontal or vertical direction. To achieve such a large deflection range, the structure of the beam deflection element 102 can be optimized. For example, if an electrowetting adjustable prism array is used, the transparent cavity and electrode structure can be precisely designed, and conductive and non-conductive liquids with a large difference in refractive index can be selected to generate a sufficiently large liquid interface tilt angle when a driving voltage is applied. If an electrowetting adjustable lens array is used, the geometry of the lens unit and the liquid filling method can be optimized to achieve a larger beam deflection under the action of an electric field.

[0081] The optical transmittance of the beam deflection element 102 is greater than or equal to 85%, meaning that at least 85% of the light energy can penetrate and exit when the beam passes through the element. High optical transmittance is crucial for ensuring the brightness and contrast of the display image. If the transmittance is too low, the display image will be dim, affecting the visual effect of the naked-eye 3D display. To achieve this requirement, the constituent materials of the beam deflection element 102, including the transparent cavity material, the liquid medium, and any possible hydrophobic insulating layer, must be optical-grade materials with extremely low absorption and scattering losses. At the same time, it should be ensured that the liquid interface is flat and smooth to reduce interface reflection and scattering, and the application of an anti-reflection coating on the surface of the element can be considered.

[0082] The optical response time of the beam deflection element 102 is less than one millisecond, meaning that the time required for the element to complete beam deflection adjustment from receiving a control signal does not exceed one millisecond. A fast response time is crucial for dynamically tracking the human eye's position and achieving smooth, glasses-free stereoscopic display. If the response time is too long when the human eye's position moves rapidly or when the displayed content needs to switch parallax views quickly, it will cause image lag, blurring, or ghosting, severely impacting the viewing experience. For the beam deflection element 102 based on the electrowetting principle, its response speed is mainly affected by factors such as liquid viscosity, density, surface tension, and electric field strength. By selecting a low-viscosity, low-density liquid, optimizing the electrode structure to generate a stronger electric field, and finely controlling the driving voltage waveform, the response time can be effectively shortened, enabling it to work synchronously with the high refresh rate display panel 103.

[0083] In this application, the beam deflection element 102 possesses a wide adjustable beam deflection angle range, high optical transmittance, and fast optical response time, thereby improving the overall performance of the naked-eye stereoscopic display device 100. The wide deflection angle range allows the display device 100 to effectively cover a larger viewing area, allowing users to move their heads freely within a certain range without worrying about image distortion or loss of stereoscopic effect, greatly enhancing viewing comfort and freedom. High optical transmittance ensures the brightness and clarity of the displayed image, making the naked-eye stereoscopic image vivid and lifelike, enhancing visual immersion. The fast optical response time ensures that the beam deflection element 102 can accurately follow the changes in the human eye position detected by the acquisition unit 104 in real time, and achieve high synchronization with the high-frequency parallax view switching of the display panel 103.

[0084] As an example, the display device 100 can specifically be a naked-eye 3D display device based on electrowetting lens dynamic collimation backlight; the acquisition unit can specifically be an eye-tracking unit; the beam deflection element can specifically be a beam deflector; the naked-eye 3D display device includes: a backlight module for providing collimated illumination beam; an electrowetting beam deflector disposed between the light-emitting side of the backlight module and the light-incident side of the display panel, comprising an electrowetting adjustable prism array or an electrowetting adjustable microlens array composed of conductive and non-conductive liquids, which changes the tilt angle or curvature of the interface between the two liquids by applying a driving voltage to achieve electrically controlled dynamic deflection of the direction of the backlight emitted beam; a display panel disposed on the light-emitting side of the electrowetting beam deflector for displaying images; and a control unit for applying a driving voltage to the electrowetting beam deflector in 3D display mode to selectively guide the illumination beam to the left-eye viewing area or the right-eye viewing area, and synchronously controlling the display panel to display the corresponding view.

[0085] For example, an electrowetting beam deflector replaces the slit grating and reverse prism in traditional glasses-free 3D displays. It utilizes the electrowetting effect to electrically control the deflection of the backlight beam, selectively guiding the backlight to different viewing areas. Combined with view switching on the display panel, it achieves glasses-free stereoscopic vision. The 3D display device includes: a backlight module located at the bottom layer for providing an illumination beam. The backlight module can use side-lit or direct-lit LED backlighting, preferably a collimated backlight scheme, to give the emitted beam better directionality and improve the deflection efficiency of the electrowetting beam deflector. The electrowetting beam deflector, located on the light-emitting side of the backlight module, includes at least one electrowetting beam deflection unit. By applying a driving voltage, the electrowetting beam deflector uses the electrowetting effect to change the interface shape or tilt angle between the conductive and non-conductive liquids inside, causing the beam passing through it to deflect, thereby achieving electrically controlled adjustment of the emitted beam direction, allowing the emitted beam direction to alternately switch between a first angle and a second angle. The electrowetting beam deflector has the following characteristics: beam deflection angle range of not less than ±15° (preferably ±25°), optical transmittance of not less than 85%, and response time of less than 1ms (preferably less than 0.5ms). A display panel, located on the light-emitting side of the electrowetting beam deflector, is used to alternately display the left-eye and right-eye views according to a timing control signal. The display panel is preferably a liquid crystal display (LCD), but other types of display panels such as OLED and micro-LED can also be used. An eye-tracking unit is used to detect the spatial position of the viewer's eyes in real time and generate left-eye and right-eye position information. The eye-tracking unit includes at least one infrared camera and an image processing module. A control unit is electrically connected to the backlight module, the electrowetting beam deflector, and the display panel. The control unit is configured to: in 3D display mode, apply a driving voltage to the electrowetting beam deflector, causing it to direct the backlight beam to the left-eye viewing area at time T1 and the right-eye viewing area at time T2; and calculate the target beam deflection angles corresponding to the left-eye and right-eye directions based on the eye-eye position information fed back by the eye-tracking unit. A first driving voltage is generated and applied to the electrowetting beam deflector, causing it to direct the beam towards the left eye, while simultaneously controlling the display panel to display the left-eye view; a second driving voltage is generated and applied to the electrowetting beam deflector, causing it to direct the beam towards the right eye, while simultaneously controlling the display panel to display the right-eye view; the above two timing sequences are executed alternately at a frequency of not less than 60Hz (preferably 120Hz). In 2D display mode, zero voltage or a specific voltage is applied to the electrowetting beam deflector, causing it to be in a non-deflected state, and the backlight is emitted uniformly.

[0086] Electrowetting beam deflectors include two preferred implementation methods: Method 1: An electrowetting adjustable prism employs a cavity structure containing a first fluid and a second fluid. These two fluids are immiscible and have different refractive indices. The first fluid is a conductive liquid (such as water or a salt solution), and the second fluid is a non-conductive liquid (such as silicone oil or alkanes). Electrode structures are provided on the cavity sidewalls. By applying voltage to the electrodes, the tilt angle of the interface between the two fluids is changed, achieving prism-like deflection of the beam. Method 2: An electrowetting adjustable microlens array employs a microlens array structure, where each microlens unit is an electrowetting adjustable lens. By controlling the focal length and optical axis direction of each lens unit, combined control of beam convergence and deflection is achieved. In the super-hybrid lens grating, the metasurface structure layer and the aspherical layer correspond one-to-one, and the aspherical and metasurface layers can be arbitrarily combined and stacked to achieve the same or similar benefits.

[0087] The following example illustrates a time-series glasses-free 3D display driving method based on electrowetting lens dynamic collimation backlighting, including the following steps: Step 1: Position detection. The spatial coordinates L(x1,y1,z1) and R(x2,y2,z2) of the viewer's left and right eyes in the current coordinate system are obtained through the eye-tracking unit.

[0088] Step 2: Angle calculation. The control unit calculates the target deflection angles θ_L and θ_R required for the emitted beam from the electrowetting beam deflector based on the left eye coordinate L and the right eye coordinate R.

[0089] Step 3: Timing control, executed sequentially within one display cycle T: First timing (t1~t2): Apply a first driving voltage V_L to the electrowetting beam deflector, deflecting its emitted beam direction to θ_L; simultaneously control the display panel to refresh and display the left eye view; control the backlight module to turn on illumination. Second timing (t2~t3): Apply a second driving voltage V_R to the electrowetting beam deflector, deflecting its emitted beam direction to θ_R; simultaneously control the display panel to refresh and display the right eye view; control the backlight module to turn on illumination. The durations of t1~t2 and t2~t3 are equal, and the reciprocal of the display cycle T (i.e., the refresh rate) is not less than 60Hz.

[0090] Step 4: Closed-loop correction. After every N display cycles (N is a preset positive integer, preferably N=1~10), steps 1 to 3 are re-executed to dynamically adapt to the viewer's head movement. The device of this application also features 2D / 3D display mode switching: 3D mode: Following the above-described timing drive method, the beam is alternately directed to the left and right eyes, forming stereoscopic vision by alternating left and right eye views. 2D mode: The control unit applies zero voltage or a constant voltage (usually to flatten the fluid interface, eliminating deflection effects) to the electrowetting beam deflector; simultaneously, it controls the display panel to display a single 2D image; the control unit can optionally disable the alternating refresh mechanism, allowing the display panel to continuously display the same image.

[0091] Example 1: A time-series naked-eye 3D display device based on an electrowetting adjustable prism array. Figure 2 This is a schematic diagram of the display device in the embodiments of this application, such as... Figure 2 As shown, the device includes: a backlight module 10, an electrowetting beam deflector 20, a display panel 30, an eye-tracking unit 40, and a control unit 50. The backlight module 10 uses a laser diode array in conjunction with a collimating lens group to output a parallel beam with collimation better than ±2°. The electrowetting beam deflector 20 is an electrowetting adjustable prism array, with each prism unit corresponding to a pixel column of the display panel. Figure 3 This is a schematic diagram illustrating the structure and working principle of the wetting adjustable prism unit in the embodiments of this application, as shown below. Figure 3 As shown, each prism unit includes: a transparent cavity 21, a conductive first fluid 22 (e.g., water), a non-conductive second fluid 23 (e.g., silicone oil), a first electrode 24, a second electrode 25, and a hydrophobic insulating layer 26. When a voltage V is applied, the contact angle θ of the interface (27) between the two fluids changes, and the interface tilt angle changes accordingly, thereby achieving prism-like deflection of the incident beam. Experimentally, this electrowetting adjustable prism unit can achieve a beam deflection angle adjustment of ±20° within a driving voltage range of 0-60V, with a response time of approximately 0.3ms and an optical transmittance of approximately 88%. The display panel 30 uses a high-speed liquid crystal panel with a response time of 4ms, a resolution of 1920×1080, and a refresh rate of 120Hz. The eye-tracking unit 40 includes two infrared cameras and an embedded image processing chip, which can achieve eye position tracking accuracy of 60fps (error < ±5mm). The control unit 50 uses an FPGA or ASIC chip to implement timing control. Figure 4 This is a schematic diagram of the relationship between the beam deflection angle and the applied voltage in an embodiment of this application, as shown below. Figure 4As shown, the control unit alternately outputs drive voltages V_L and V_R at a frequency of 120Hz (period T≈8.33ms), with each sub-timing lasting approximately 4.16ms. During the action of V_L, the display panel refreshes the left-eye view; during the action of V_R, the display panel refreshes the right-eye view. When the viewer's head moves, the eye-tracking unit 40 detects the new eye positions in real time, and the control unit 50 recalculates θ_L and θ_R, updating the drive voltages V_L and V_R to achieve dynamic eye-tracking adaptation.

[0092] Verification has shown that the device in this embodiment can achieve naked-eye 3D display without crosstalk at a viewing distance of 40cm. The viewer can maintain stable stereoscopic vision and no obvious dizziness when the head moves within a range of ±10cm.

[0093] In Example 2, the electrowetting beam deflector 20 employs an electrowetting adjustable microlens array instead of a prism array. In the microlens array scheme, each microlens unit is an electrowetting adjustable lens. By controlling the applied voltage, the focal length and optical axis direction of the lens can be continuously adjusted. In the first time sequence, the lens array converges and deflects the backlight towards the left eye; in the second time sequence, it converges and deflects it towards the right eye. Compared to the prism array scheme, the microlens array scheme has higher light energy utilization efficiency (transmittance up to 92%) and more flexible viewing area shape adjustment capabilities, making it suitable for display scenarios requiring a wider eye box range.

[0094] The specific details of the dynamic eye-tracking closed-loop control in this embodiment can be combined with... Figure 5 To understand, Figure 5 This is a schematic diagram of the dynamic eye-tracking closed-loop control in the embodiments of this application.

[0095] The display device provided in the embodiments of this application has been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is 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 they can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for 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 display device, characterized in that, It includes a backlight module, a beam deflection element, a display panel, a data acquisition unit, and a control unit: the beam deflection element is disposed between the backlight module and the display panel, and the control unit is connected to the backlight module, the beam deflection element, the display panel, and the data acquisition unit respectively; The backlight module is used to output a parallel illumination beam; The acquisition unit is used to detect the position of the human eye and output the detection signal of the human eye position; The control unit is configured to control the beam deflection element to guide the illumination beam to the viewing area corresponding to the human eye position according to the detection signal, and to control the display panel to alternately display different parallax views at a preset frequency, wherein the preset frequency is greater than or equal to the set screen alternation frequency; The beam deflection element comprises at least two immiscible liquids with different refractive indices, including conductive and non-conductive liquids. The beam deflection element is used to adjust the emission direction of the illumination beam in a non-obstructive manner, and to project images onto the viewing area in a time-division manner in conjunction with the display panel.

2. The display device according to claim 1, characterized in that, The control unit is also used to determine the beam target deflection angle adapted to the viewing area based on the detection signal, output a driving voltage according to the target deflection angle, and control the display panel to switch the parallax view in a timing sequence of the preset frequency; The beam deflection element is also used to change the interface morphology of the at least two liquids based on the driving voltage, so as to adjust the emission angle of the parallel illumination beam without obstruction, and to project the image to the corresponding viewing area in a time-division manner with the display panel.

3. The display device according to claim 2, characterized in that, The beam deflection element includes an electrowetting adjustable prism array; the electrowetting adjustable prism array includes a transparent cavity and an electrode structure, the electrode structure being disposed on the sidewall of the transparent cavity; The transparent cavity is used to contain the at least two liquids; The electrode structure is used to apply the driving voltage, change the tilt angle of the interface between the at least two liquids, and cause the parallel illumination beam to undergo prism-like deflection.

4. The display device according to claim 3, characterized in that, The beam deflection element further includes a hydrophobic insulating layer; the hydrophobic insulating layer is disposed on the inner wall of the transparent cavity; The hydrophobic insulating layer is used to regulate the contact state between the conductive liquid and the inner wall, and to stabilize the tilt angle of the interface formed by the at least two liquids.

5. The display device according to claim 2, characterized in that, The beam deflection element includes an electrowetting adjustable lens array; the electrowetting adjustable lens array includes at least two independent lens units, each of which contains the conductive liquid and the non-conductive liquid; The electrowetting adjustable lens array is used to change the interface curvature of the at least two liquids based on the driving voltage, so as to control the convergence and angle deflection of the parallel illumination beam.

6. The display device according to claim 1, characterized in that, The acquisition unit includes an infrared camera and an image processing module; the infrared camera is connected to the image processing module. The infrared camera is used to capture regional images of the viewing area where the human eye is located; The image processing module is used to parse the region image, obtain the spatial coordinates of the human eye, and generate the detection signal based on the spatial coordinates.

7. The display device according to claim 2, characterized in that, The control unit is also used to re-determine the beam target deflection angle adapted to the human eye position based on the detection signal after each preset number of screen alternation cycles, and update the driving voltage to control the beam deflection element to dynamically adjust the emission direction of the illumination beam as the human eye moves.

8. The display device according to claim 1, characterized in that, The control unit is also used to output zero voltage or constant voltage to the beam deflection element in the display control mode of the planar image, so that the interface between the conductive liquid and the non-conductive liquid remains flat, the parallel illumination beam is emitted uniformly and vertically, and the display panel is controlled to continuously output a single planar image, and the alternation switching of the parallax view is turned off.

9. The display device according to claim 8, characterized in that, The backlight module includes one of the following: a laser diode with a collimating lens group, a side-lit collimated LED backlight, and a direct-lit collimated LED backlight; the divergence angle of the parallel illumination beam output by the laser diode with the collimating lens group is no greater than ±2 degrees; the side-lit collimated LED backlight and the direct-lit collimated LED backlight are used to output the parallel illumination beam.

10. The display device according to claim 8, characterized in that, The display panel includes one of a liquid crystal panel, an organic light-emitting panel, and a micro light-emitting panel; The display panel is used to output different parallax views in a time-division manner or continuously output a single planar image according to the timing instructions of the control unit.

11. The display device according to any one of claims 1-10, characterized in that, The beam deflection element has an adjustable deflection angle range greater than or equal to ±15 degrees, an optical transmittance greater than or equal to 85%, and an optical response time less than one millisecond. The beam deflection element is also used to adjust the emission angle of the parallel illumination beam without obstruction, and to guide the parallel illumination beam to the viewing area corresponding to the human eye in a time-division manner, so as to realize naked-eye stereoscopic display.

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