Display device

Abstract

A display device is provided, including a housing, a display unit, a laser light source, and an optical fiber. At least a portion of the display unit is disposed within the housing; the display unit includes a display screen and a light guide plate, the light guide plate being located on the light-incident side of the display screen; the laser light source is disposed outside the housing; the optical fiber connects the light guide plate and the laser light source; wherein the light-emitting surface of the light guide plate faces the display screen, and the laser emitted from the laser light source is configured to pass through the optical fiber and enter the light guide plate, and then enter the display screen from the light-emitting surface. The display device provided in this disclosure, with its laser light source, helps improve the luminous efficiency of the display screen, achieving a wider color gamut and higher contrast, resulting in more accurate and clearer colors and images on the display screen. Furthermore, the connection between the display unit and the laser light source via the optical fiber allows for the separation of the display screen and the laser light source, which helps reduce the weight of the display unit and facilitates better heat dissipation for the laser light source.

Description

Technical Field

[0001] At least one embodiment of this disclosure relates to a display device. Background Technology

[0002] Mixed Reality (MR) display technology is a technology that combines the real and virtual worlds, allowing users to see and interact with virtual objects or information in a real environment. However, some devices using MR display technology suffer from poor wearing comfort, impacting the user experience. Summary of the Invention

[0003] At least one embodiment of this disclosure provides a display device, comprising: a housing; a display unit, at least partially disposed within the housing; the display unit including a display screen and a light guide plate, the light guide plate being located on the light-incident side of the display screen; a laser light source disposed outside the housing; and an optical fiber connected between the light guide plate and the laser light source; wherein the light-emitting surface of the light guide plate faces the display screen, and the laser emitted from the laser light source is configured to pass through the optical fiber and enter the light guide plate, and then enter the display screen from the light-emitting surface.

[0004] For example, according to at least one embodiment of the present disclosure, the display device includes a near-eye display device configured such that only the housing is worn on the user's head.

[0005] For example, according to at least one embodiment of the present disclosure, the display device further includes a power supply disposed outside the housing, the power supply being configured to supply power to the laser light source.

[0006] For example, according to at least one embodiment of this disclosure, the display device further includes a light source device disposed outside the housing, wherein both the power supply and the laser light source are disposed within the light source device.

[0007] For example, according to at least one embodiment of the present disclosure, the light guide plate includes a dimming layer located on the light-emitting surface, the dimming layer being configured to modulate the laser.

[0008] For example, according to at least one embodiment of this disclosure, the dimming layer includes at least one of a microlens, a surface relief grating, a holographic grating, and a metasurface.

[0009] For example, according to at least one embodiment of this disclosure, the display screen is a liquid crystal display screen, the display screen includes a black matrix defining a plurality of pixel openings; the dimming layer includes a microstructure region, the microstructure region being configured as a plurality of such regions corresponding one-to-one with a corresponding number of the plurality of pixel openings, and the orthographic projection of the pixel openings on the display surface of the display screen at least partially overlaps with the orthographic projection of the microstructure region on the display surface; the microstructures within the microstructure region are configured to modulate the laser.

[0010] For example, according to at least one embodiment of this disclosure, at least one of the microstructure regions is connected to the center line of its corresponding pixel opening perpendicular to the display surface.

[0011] For example, according to at least one embodiment of the present disclosure, the outer contour of the orthographic projection of the microstructure region on the display surface coincides with the outer contour of the orthographic projection of the pixel opening on the display surface.

[0012] For example, according to at least one embodiment of this disclosure, the display unit further includes an optical system, the display screen is located between the optical system and the light guide plate along the optical axis of the optical system, and the display surface of the display screen faces the optical system; wherein, the optical system includes a lens structure, a transflective coating, a reflective polarizing layer, a phase retardation film, and a linear polarizing film; the lens structure includes a first surface and a second surface along the optical axis; the transflective coating is located between the first surface and the display surface, the reflective polarizing layer is located on the side of the second surface away from the first surface, the phase retardation film is located on the side of the first surface away from the transflective coating, and the linear polarizing film is located on the side of the reflective polarizing layer away from the transflective coating.

[0013] For example, according to at least one embodiment of the present disclosure, the laser source includes at least two backlights configured to emit lasers of different colors.

[0014] For example, according to at least one embodiment of the present disclosure, the laser source includes a first backlight configured to emit red laser light, a second backlight configured to emit green laser light, and a third backlight configured to emit blue laser light; the laser light emitted by the first backlight, the second backlight, and the third backlight is configured to mix in the optical fiber to form white light.

[0015] For example, according to at least one embodiment of the present disclosure, the display device further includes a speckle eliminator disposed outside the housing, the speckle eliminator being connected between the optical fiber and the laser light source.

[0016] For example, according to at least one embodiment of the present disclosure, the display device further includes a light source device disposed outside the housing, wherein both the speckle eliminater and the laser light source are disposed inside the light source device.

[0017] For example, according to at least one embodiment of this disclosure, the optical fiber is a multimode optical fiber.

[0018] For example, according to at least one embodiment of this disclosure, the laser emitted from the laser source is polarized light. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings of the embodiments will be briefly described below. Obviously, the drawings described below only relate to some embodiments of this disclosure and are not intended to limit this disclosure.

[0020] Figure 1 This is a schematic diagram of a display device provided as an example in at least one embodiment of the present disclosure.

[0021] Figure 2 for Figure 1 The diagram shows a partial structure of the display device.

[0022] Figure 3 Color gamut diagrams for different displays.

[0023] Figure 4 This is a schematic diagram of a display screen and a light guide plate provided as an example in at least one embodiment of the present disclosure.

[0024] Figure 5A and Figure 5B This is a schematic diagram of a light guide plate provided in at least one embodiment of the present disclosure, representing different examples.

[0025] Figure 6 This is a schematic diagram of an optical system provided as an example in at least one embodiment of the present disclosure. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. Based on the described embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0027] Unless otherwise defined, the technical or scientific terms used in this disclosure shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as “comprising” or “including” mean that an element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects.

[0028] The terms "parallel," "perpendicular," and "identical" as used in this disclosure include the strictly defined meanings of "parallel," "perpendicular," and "identical," as well as terms such as "approximately parallel," "approximately perpendicular," and "approximately identical," which include a certain degree of error. Taking into account measurement and errors associated with the measurement of a specific quantity (i.e., limitations of the measurement system), they represent acceptable deviations for a specific value as determined by a person skilled in the art. In embodiments of this disclosure, "center" can include a strictly defined location at the geometric center as well as a location approximately at the center within a small area surrounding the geometric center. For example, "approximately" can mean within one or more standard deviations, or within 10% or 5% of the value.

[0029] MR equipment consists of two key components: a display screen and a lens assembly. The display screen is used to show images and can employ either a liquid crystal display (LCD) or an organic light-emitting diode (OLED) technology. By controlling the alignment of liquid crystal molecules or the emission of light from organic materials, the light can be modulated and controlled, thereby producing the desired image.

[0030] The following explanation uses an LCD microdisplay as an example. An LCD microdisplay consists of multiple components that work together to achieve high-quality image display. For example, an LCD microdisplay includes a liquid crystal panel, a backlight module, a driving circuit, a control circuit, a housing, and a support frame.

[0031] A liquid crystal panel can be composed of two glass substrates and liquid crystal molecules filling the space between the two glass substrates. Each pixel on the liquid crystal panel is controlled by a thin film transistor (TFT), which can control the amount of light transmission by changing the alignment of the liquid crystal molecules, thereby enabling image display.

[0032] The backlight module provides a light source so that the image displayed on the LCD panel can be seen by the human eye. The backlight module can include a cold cathode fluorescent lamp (CCFL) or a light-emitting diode (LED). LED backlights are particularly popular due to their advantages such as long lifespan, high brightness, and low power consumption.

[0033] The driving circuit controls the voltage of each pixel on the liquid crystal panel, thereby controlling the alignment of the liquid crystal molecules. The driving circuit includes an integrated circuit (IC), which converts image data into driving voltage signals and sends them to the liquid crystal panel.

[0034] The control circuit receives external signals, such as television signals and computer signals, and converts these signals into a format suitable for display on the LCD panel. The control circuit may include a microcontroller unit (MCU) or a digital signal processor (DSP) and is used to control parameters such as the display mode, brightness, and contrast of the LCD panel.

[0035] The housing and bracket are used to fix components such as the LCD panel, backlight module, driving circuit and control circuit, and to provide protection and support for these components.

[0036] In their research, the inventors of this application discovered that MR devices are relatively heavy, and prolonged wear can cause strain on the user's head and neck. Furthermore, the heat generated during operation is difficult to dissipate effectively. Especially during extended use, overheating can negatively impact user experience and device stability, hindering the improvement of the MR device's power output. In addition, the optical performance of MR devices needs further improvement.

[0037] At least one embodiment of this disclosure provides a display device, including a housing, a display unit, a laser light source, and an optical fiber. At least a portion of the display unit is disposed within the housing; the display unit includes a display screen and a light guide plate, the light guide plate being located on the light-incident side of the display screen; the laser light source is disposed outside the housing; the optical fiber connects the light guide plate and the laser light source; wherein the light-emitting surface of the light guide plate faces the display screen, and the laser emitted from the laser light source is configured to pass through the optical fiber and enter the light guide plate, and then enter the display screen from the light-emitting surface.

[0038] The display device provided in at least one embodiment of this disclosure uses a laser light source to improve the luminous efficiency of the display screen, enabling a wider color gamut and higher contrast, thus allowing the display screen to present more accurate and clearer colors and images. Furthermore, the display unit is connected to the laser light source via optical fiber, allowing for separation of the display screen and the laser light source, which helps reduce the weight of the display unit and facilitates better heat dissipation for the laser light source.

[0039] The display device will now be described in conjunction with the accompanying drawings and through some embodiments.

[0040] Figure 1 This is a schematic diagram of a display device provided as an example in at least one embodiment of the present disclosure. Figure 2 for Figure 1 The diagram shows a partial structure of the display device.

[0041] refer to Figure 1 and Figure 2 This disclosure provides at least one embodiment of a display device, which includes a housing 10, a display unit 100, a laser light source 200, and an optical fiber 300. At least a portion of the display unit 100 is disposed within the housing 10. For example, the display unit may be entirely located within the housing, or a portion may be disposed within the housing while the other portion protrudes from the housing, as will be described in detail in the embodiments described later.

[0042] refer to Figure 1 and Figure 2 The display unit 100 includes a display screen 110 and a light guide plate 120, with the light guide plate 120 located on the light-incident side of the display screen 110. For example, the display screen 110 and the light guide plate 120 can both be housed within a housing. The laser light source 200 is located outside the housing 10. Thus, the display device can achieve a split design, with the display screen 110 and the laser light source 200 being separable from each other.

[0043] refer to Figure 1 and Figure 2 The light-emitting surface 121 of the light guide plate 120 faces the display screen 110. The laser emitted from the laser source 200 is configured to pass through the optical fiber 300 into the light guide plate 120 and then into the display screen 110 from the light-emitting surface 121. For example, the laser source can serve as the backlight for the display screen, providing the background light required for display. Thus, the laser emitted from the laser source 200 can enter the light guide plate 120 through the optical fiber 300 and then enter the display screen 110 from the light-emitting surface 121 of the light guide plate 120, thereby displaying an image.

[0044] refer to Figure 1 and Figure 2The display device provided in at least one embodiment of this disclosure uses a laser light source 200 to improve the luminous efficiency of the display screen 110, enabling a wider color gamut and higher contrast, thus allowing the display screen 110 to present more accurate and clearer colors and images. Furthermore, the display unit 100 is connected to the laser light source 200 via an optical fiber 300, allowing for the separation of the display screen 110 and the laser light source 200. This reduces the weight of the display unit 100 and facilitates better heat dissipation for the laser light source 200, thereby reducing the power consumption of the display device.

[0045] Figure 3 Color gamut diagrams for different displays.

[0046] like Figure 3 As shown, compared to LED display screen 01, LCD display screen 02 with LED backlight, and Cathode Ray Tube (CRT) display screen 03, display screen 04 with laser backlight can achieve a wider color gamut. The color gamut of a display screen refers to the range of colors it can display. Since the display screen displays colors by mixing the three primary colors RGB, the color gamut of each display screen is represented by a triangle on the chromaticity diagram. The three vertices of the triangle are the chromaticity diagram coordinates measured by a color analyzer when the display screen displays full red, full green, and full blue fields.

[0047] refer to Figure 3 Since the three primary colors of LCD display 02 and LED display 01, which use LED as backlight, are all located within the edge of the color gamut, while the three primary colors of display 04, which uses laser as backlight, are located at the edge of the color gamut, the color gamut triangle of display 04, which uses laser as backlight, has a larger area, that is, a wider coverage.

[0048] Therefore, the laser light source in this embodiment of the present disclosure is beneficial to make the screen display richer and more vivid colors and more distinct light and dark contrasts, making the color representation of virtual objects and scenes closer to the real world, and enhancing the visual immersion and realism.

[0049] Below, we will compare the efficiency of LED displays using LEDs as backlights and laser displays using lasers as backlights from multiple perspectives.

[0050] Wall-plug efficiency is the energy conversion efficiency from electrons to photons. The wall-plug efficiency of an LED display is approximately 70%. The coupling efficiency of an LED backlight is 100%. The light emitted by the LED backlight is unpolarized. However, when the display device includes an optical system forming a folded optical path as described in the embodiments below, the light incident on the optical system needs to be polarized. Therefore, it is necessary to convert the light emitted by the LED backlight into polarized light. Based on this, the polarization control of the LED backlight is estimated at 60%, which means there is approximately 40% polarization conversion loss.

[0051] The wall-mount efficiency of the laser display screen is approximately 30%. In conjunction with the embodiments described later, the laser source is coupled to the light guide plate via a speckle eliminator and multimode fiber, achieving a coupling efficiency of approximately 80%. In some examples, the laser emitted by the laser source is polarized light. For instance, the laser emitted by the laser source can be linearly polarized, circularly polarized, elliptically polarized, etc., and this disclosure does not impose any limitations on this. Because the laser emitted by the laser source is polarized light, it has better polarization characteristics, which can eliminate some polarization conversion loss. The polarization control of the laser source is approximately 90%, meaning there is approximately 10% polarization conversion loss.

[0052] Furthermore, compared to an LCD display with a low fill factor and a color filter, the transmittance of an LED display is approximately 1.5%. A laser display can replace the color filter by coordinating the laser light source and timing. Simultaneously, in conjunction with the embodiments described later, the microstructure in a laser display can be better matched to the pixel apertures, thereby achieving a transmittance of approximately 9%.

[0053] Multiplying the efficiencies of the LED display screen in each dimension yields a total efficiency of approximately 0.0063. Multiplying the efficiencies of the laser display screen in each dimension yields a total efficiency of approximately 0.0194. Therefore, a display screen using a laser light source can achieve a 3-fold increase in luminous efficacy.

[0054] Compared to LED-based backlight displays, laser-based displays can significantly increase instantaneous power and absolute brightness. For example, to achieve High Dynamic Range (HDR) display, some display devices including LED backlights and optical systems forming folded light paths can achieve a peak brightness of 100 nits, while HDR displays require a peak brightness of 1000 nits. The laser-based display provided in this disclosure can meet the peak brightness requirements of HDR displays with approximately 3.3 times the luminous efficacy and approximately 3.3 times the power, thus achieving the goal of a tenfold increase in peak brightness. For example, in some LED-based backlight displays, the backlight power is 0.9W. The laser-based display provided in this disclosure can achieve a backlight power of 6W.

[0055] refer to Figure 2 In some examples, the laser source 200 includes at least two backlight sources configured to emit lasers of different colors, so as to form a mixed light as the backlight of the display screen 110 by mixing the different colors of laser light. The specific type of laser source can be flexibly set according to the specific color requirements of the formed mixed light, and this disclosure does not limit it.

[0056] refer to Figure 2 In some examples, the laser source 200 includes a first backlight 201 configured to emit a red laser RL, a second backlight 202 configured to emit a green laser GL, and a third backlight 203 configured to emit a blue laser BL. For example, the first backlight 201, the second backlight 202, and the third backlight 203 can be mixed in the optical fiber 300 to form mixed light of different colors. For example, the lasers emitted by the first backlight 201, the second backlight 202, and the third backlight 203 are configured to be mixed in the optical fiber 300 to form white light.

[0057] refer to Figure 1 and Figure 2 In some examples, the display device includes a near-eye display device. A near-eye display device is a device that presents images or information to a user's eyes at close range, and can be worn on the head or near the eyes, allowing the user to see magnified virtual images within a small area in front of their eyes. For example, the display device can be a wearable VR headset, VR glasses, wearable MR headset, MR glasses, etc., and the embodiments disclosed herein are not limited thereto.

[0058] refer to Figure 1 and Figure 2The near-eye display device is configured such that only the housing 10 is worn on the user's head. For example, the housing can be a headband structure within the near-eye display device. Because the display device is a split design, the user can wear only the housing 10, making the user-worn part lighter and smaller, and effectively reducing the impact of heat from the laser source 200 on the user.

[0059] refer to Figure 1 and Figure 2 For example, the laser light source 200 can be placed at a location far from the housing 10. In some examples, the display device also includes a light source device BX, within which the laser light source 200 can be housed. For example, the laser light source 200 can be integrated into the light source device BX and carried separately. For example, the light source device BX can be a light source box.

[0060] The display unit in a display device has a limited volume, leaving little space for a heat dissipation system. Moreover, the display unit integrates multiple heat sources such as the processor and the display screen. Integrating the backlight and the display unit together in the housing would result in uneven heat distribution.

[0061] refer to Figure 1 and Figure 2 By separating the laser light source 200 from the display unit 10 and placing it outside the housing 10, the housing 10 worn by the user will not overheat, preventing discomfort and ensuring a smooth user experience. Furthermore, separating the laser light source 200 from the display unit 100 helps prevent overheating of the electronic components within the display unit 100, thus extending the lifespan of the display device. Preventing overheating of the display unit 100 also prevents system crashes, screen stuttering, and other issues, avoiding negative impacts on the user experience. Additionally, it prevents safety hazards such as battery overheating and fires caused by overheating of the display unit 100.

[0062] Furthermore, the integration of multiple components, such as the display screen, processor, sensors, and battery, increases the weight of some display devices. Additionally, cooling components are needed to meet the heat dissipation requirements, further increasing weight. Moreover, selecting suitable materials is crucial for ensuring performance and durability, and high-performance materials are often heavier. Extending battery life requires larger capacity batteries, and battery weight also makes it difficult to reduce the overall weight of the display device. Therefore, wearing these display devices on the head can negatively impact user comfort.

[0063] refer to Figure 1 and Figure 2In this embodiment, the display device separates the laser light source 200 from the display unit 100, enabling a lighter user-wearing component. This prevents the user's head from being compressed due to excessive weight, allowing for extended wear without discomfort. It also prevents issues such as dizziness and neck discomfort from affecting the user experience, thus improving comfort and reducing fatigue. Furthermore, the lighter weight reduces the user's presence, enhancing immersion in the virtual world. Additionally, the lighter component is easier to carry, allowing for convenient use anytime, anywhere.

[0064] refer to Figure 1 In some examples, the display device also includes a power supply 400 disposed outside the housing 10, configured to supply power to the laser light source 200. For example, the power supply 400 can be electrically connected to the laser light source 200 via a wire W. By placing the power supply 400 outside the housing 10, the weight of the user-worn portion can be reduced. Moreover, since the power supply 400 is located away from the user's head, the heat generated by the power supply 400 has a reduced impact on the user, allowing the power supply 400 to be configured with a larger capacity to improve the display device's battery life.

[0065] For example, the power supply can be located within the light source device. For example, the power supply can be located together with the laser light source within the light source device, so as to be integrated into the light source device, and this disclosure does not limit this.

[0066] refer to Figure 1 and Figure 2 In some examples, the display device also includes a de-speckler 500 connected between the optical fiber 300 and the laser source 200. The de-speckler 500 can eliminate speckle in the light emitted from the laser source 200, thereby reducing speckle in the displayed image and improving image quality. For example, the de-speckler 500 can be integrated with the laser source 200 within the light source device BX.

[0067] In some examples, the optical fiber is multimode fiber to allow light to propagate through the fiber along different paths. Using multimode fiber can effectively reduce speckle and improve image contrast and resolution. Furthermore, speckle cancellers work by reducing the spatial coherence of the laser; if single-mode fiber were used, the spatial coherence of the laser would be enhanced again because low-spatial-coherence light would be filtered out.

[0068] For example, the wavelength of the multimode fiber can be matched with the wavelength of the laser emitted from the laser source. For instance, in a laser source comprising a first backlight configured to emit red laser light, a second backlight configured to emit green laser light, and a third backlight configured to emit blue laser light, the three wavelengths of the laser emitted by the laser source correspond to the center wavelengths of RGB, respectively. For example, the wavelength of R is 650 nm, the wavelength of G is 532 nm, and the wavelength of B is 450 nm.

[0069] refer to Figure 1 and Figure 2 In some examples, the light guide plate 120 includes a dimming layer 122 located on the light-emitting surface 121, the dimming layer 122 being configured to modulate the laser. For example, the light guide plate includes a light-guiding portion for total internal reflection transmission and a dimming layer located on the light-emitting side of the light-guiding portion. For example, the dimming layer 122 can modulate at least one of the polarization, phase, amplitude, and deflection of the laser. For example, the dimming layer 122 can modulate the coupling angle of the laser, which is beneficial to improving the luminous efficiency of the display screen 110.

[0070] In some examples, the dimming layer includes at least one of a micro-lens, a surface relief grating, a holographic grating, and a meta surface.

[0071] For example, the dimming layer may consist only of microlenses. For example, the dimming layer may consist only of surface relief gratings. For example, the dimming layer may consist only of holographic gratings. For example, the dimming layer may consist only of metasurfaces. For example, the dimming layer may include any two or three of microlenses, surface relief gratings, holographic gratings, and metasurfaces. For example, the dimming layer may include microlenses, surface relief gratings, holographic gratings, and metasurfaces. This disclosure does not limit these aspects. For example, the shape of the microlens may include spherical or other shapes. For example, microlenses with different structures can be arranged on the light guide plate according to the laser control requirements to achieve light control.

[0072] For example, a surface relief grating is an optical element that achieves light diffraction by forming periodic protrusions or grooves on the surface of a material. Light can be controlled by designing parameters such as the size and tilt angle of the protrusions in the surface relief grating.

[0073] For example, a holographic grating is a grating created by interfering with two laser beams using holographic exposure. Different interference patterns can be formed by adjusting the angle and intensity of the laser beams used to create the holographic grating, thus meeting different needs for light control.

[0074] For example, a metasurface is an artificial array of structures composed of subwavelength units arranged periodically or aperiodically on a two-dimensional plane. For example, subwavelength units may include liquid crystal molecules, and light can be modulated by adjusting the arrangement of these molecules. For example, subwavelength units may include micro / nano structures such as nanopillars, and light can be modulated by adjusting the rotation angle of these nanopillars.

[0075] Figure 4 This is a schematic diagram of a display screen and a light guide plate provided as an example in at least one embodiment of the present disclosure.

[0076] refer to Figure 4 In some examples, the display screen 110 is a liquid crystal display screen. The display screen 110 includes a black matrix 111 that defines a plurality of pixel openings 112 to expose the effective light-emitting area of ​​the pixels. Within the pixels of the display screen 110, only a portion of the area is transparent due to the presence of a light-shielding layer such as control circuitry; this portion is the effective light-emitting area. For example, the black matrix includes a plurality of strip structures that are intersected to define the plurality of pixel openings. For example, the black matrix may cover signal lines in the display screen.

[0077] refer to Figure 4 The dimming layer 122 includes microstructure regions A, which are multiple in number. The microstructures within each microstructure region A are configured to control the laser beam. This embodiment uses microlenses as an example, where each microstructure region includes one microlens. However, this disclosure is not limited to this; the dimming layer can also include other forms of microstructures. For example, if the dimming layer includes a surface-embossed grating or a holographic grating, the microstructure region can include multiple microstructures such as micro / nano structures. Similarly, if the dimming layer includes a metasurface, the microstructure region can include multiple microstructures such as liquid crystal molecules.

[0078] It is understandable that, when the dimming layer includes a surface-embossed grating, the surface-embossed grating can be fabricated on one side of the light-emitting surface of the light guide plate. Multiple microstructure regions can refer to multiple areas of the surface-embossed grating, and the patterns in different areas can be the same or different. For example, the shape and arrangement of the micro / nano structures in different areas can be the same or different. Similarly, when the dimming layer includes a holographic grating, a holographic grating can be fabricated on one side of the light-emitting surface of the light guide plate. Multiple microstructure regions can refer to multiple areas of the holographic grating, and the patterns in different areas can be the same or different. For example, the shape and arrangement of the micro / nano structures in different areas can be the same or different. Finally, when the dimming layer includes a metasurface, a metasurface can be fabricated on one side of the light-emitting surface of the light guide plate. Multiple microstructure regions can refer to multiple areas of the metasurface, and the arrangement of liquid crystal molecules in different areas can be the same or different.

[0079] refer to Figure 4Multiple pixel openings 112 correspond one-to-one with a corresponding number of multiple microstructure regions A, and the orthographic projection of the pixel opening 112 on the display surface 113 of the display screen 110 at least partially overlaps with the orthographic projection of the microstructure region A on the display surface 113, so that light rays coupled from the microstructure region A can enter the pixel opening 112, thereby improving the light transmittance and enhancing the light efficiency of the display screen 110.

[0080] For example, the outer contour of the orthographic projection of the pixel opening on the display surface can completely coincide with the outer contour of the orthographic projection of the microstructure region on the display surface, thereby achieving size matching between the pixel opening and the microstructure region. For example, the orthographic projection of the pixel opening on the display surface can be located within the range of the orthographic projection of the microstructure region on the display surface, meaning the size of the pixel opening can be smaller than the size of the microstructure region. For example, the orthographic projection of the microstructure region on the display surface can be located within the range of the orthographic projection of the pixel opening on the display surface, meaning the size of the microstructure region can be smaller than the size of the pixel opening. This disclosure does not impose any limitations in this regard.

[0081] refer to Figure 4 For example, the light emitted after being modulated by the dimming layer 122 can be matched with the effective light-emitting area. For example, the orthographic projection of the microstructure region A in the dimming layer 122 onto the display surface 113 can be located within the range of the orthographic projection of the effective light-emitting area onto the display surface 113, so that the microstructure region A can be designed to be smaller, which is beneficial to reducing costs.

[0082] refer to Figure 4 In some examples, at least one microstructure region A is connected to the center of its corresponding pixel opening 112 by a line L0 perpendicular to the display surface 113, so that the microstructure region A is directly opposite the corresponding pixel opening 112, thereby maximizing the efficiency of the light emitted from the microstructure region A. For example, the arrangement of the microstructure regions A can be the same as the arrangement of the pixel openings 112 in the display screen 110.

[0083] For example, the center of the microstructure region can be its geometric center. For example, when the outer contour of the orthographic projection of the microstructure region onto the display surface is a circle, the orthographic projection of the center of the microstructure region onto the display surface can coincide with the center of that circle. For example, when the outer contour of the orthographic projection of the microstructure region onto the display surface is a rectangle, the orthographic projection of the center of the microstructure region onto the display surface can coincide with the center of that rectangle, which is also the intersection of the two diagonals of the rectangle.

[0084] For example, the center of a pixel opening can be its geometric center. For example, when the outline of a pixel opening is circular, the center of the pixel opening can be the center of the circle. For example, when the outline of a pixel opening is rectangular, the center of the pixel opening can be the center of the rectangle, that is, the intersection of the two diagonals of the rectangle.

[0085] Of course, the outer contour shape of the orthographic projection of the microstructure region on the display surface and the contour shape of the pixel opening can also be other regular closed shapes or irregular closed shapes. The outer contour shape of the orthographic projection of the microstructure region on the display surface and the contour shape of the pixel opening can be similar graphics, or they can be different. This disclosure does not impose any restrictions on these aspects.

[0086] For example, the line connecting a microstructure region to the center of its corresponding pixel opening can be perpendicular to the display surface. Alternatively, some of the microstructure regions can each have their respective pixel openings connected to the center of the display surface. Or, all the microstructure regions can each have their respective pixel openings connected to the center of the display surface.

[0087] Figure 5A and Figure 5B This is a schematic diagram of a light guide plate provided in at least one embodiment of the present disclosure, representing different examples. Figure 6 This is a schematic diagram of an optical system provided as an example in at least one embodiment of the present disclosure.

[0088] refer to Figure 5A and Figure 5B , Figure 5A and Figure 5B Different light guide plates 120a and 120b are shown, each equipped with a different microlens 122a and 122b. These microlenses allow for control of the divergence angle and spatial distribution of the coupled light rays, enabling the coupled light rays to have different divergence angles and spatial distributions as needed. For example, Figure 5A The microlens 122a shown allows the coupled light rays to exit perpendicularly. For example, Figure 5B The different microlenses 122b shown can cause the coupled light rays to exit at different angles. Thus, as Figure 6 As shown, this allows the emission angle of the display screen 110 to be better matched with the light receiving angle that the lens structure 131 in the optical system 130 can receive, thereby improving the light efficiency of the display device and facilitating the control of stray light.

[0089] refer to Figure 5A and Figure 5B For example, microlenses 122a and 122b may have different surface morphologies. For example, microlenses 122a and 122b may have different structural dimensions, such as arch height. This disclosure does not impose any limitations in this regard.

[0090] refer to Figure 6For different field of view angles seen by the human eye, the angles at which light rays 1, 2 and 3 incident into the optical system 130 exit the display surface 113 are different. These exit angles are also referred to as the receiving angles of the optical system 130.

[0091] In LED displays, the number of LEDs is less than the total number of pixels. Therefore, displays using LEDs as backlights face difficulties in matching the light emitted by the LEDs with all the pixel apertures, and also in matching the emission angle of the display with the reception angle of the optical system. Furthermore, in displays using LEDs as backlights, the wide spectrum of LEDs significantly limits the control of the LED divergence angle, further complicating the matching of the emitted light from the LEDs with the pixel apertures.

[0092] refer to Figures 4 to 6 In the display device provided in this embodiment, since a laser light source 200 is used, the laser spectrum is relatively narrow, making it easy to control the screen emission angle of the display screen 110 using the dimming layer 122. Furthermore, various types of dimming zones with different microstructures can be selected to adjust the laser, all achieving good results. Simultaneously, given a known receiving angle, by designing the dimming layer 122, the emission angle and receiving angle of the screen can be matched to the maximum extent, which helps to maximize the light emitted by the display screen 110 being received by the human eye, thus maximizing the optical efficiency of the display device.

[0093] Based on the foregoing examples, microstructures such as microlenses, surface relief gratings, holographic gratings, and metasurfaces can all be fabricated with high precision using microfabrication processes. For instance, microfabrication processes refer to the techniques used to create microstructures at the micrometer scale. These processes may include photolithography, electron beam etching, and nanoimprint lithography.

[0094] For example, high-precision microstructures can possess high positional and morphological accuracy. Microstructures with high positional accuracy ensure that the laser propagating in the light guide plate is coupled out at specific locations, which is beneficial for directing the laser into the pixel opening and reducing light loss. Microstructures with high morphological accuracy facilitate control over the divergence angle of the coupled light rays. Furthermore, microstructures at different spatial locations can be fabricated into different morphologies, thereby enabling a specific spatial distribution of the divergence angle of the coupled light rays.

[0095] For example, when the microstructure includes liquid crystal molecules, the morphology of the microstructure can refer to the arrangement or orientation of the liquid crystal molecules. For example, when the microstructure includes nanostructures, the morphology of the microstructure can refer to the tilt angle, height, or other structural parameters of the nanostructure. This disclosure does not impose any limitations in these respects.

[0096] It is understandable that microstructures such as microlenses, surface relief gratings, holographic gratings, and metasurfaces can have different microfabrication processes, different processing costs, and can also achieve different levels of positional and topographic accuracy.

[0097] For example, the precision of metasurfaces can be higher than that of surface relief gratings and holographic gratings. For example, the precision of microlenses is lower than that of surface relief gratings and holographic gratings. For example, the precision of relief gratings and holographic gratings can be approximately the same.

[0098] refer to Figure 1 and Figure 6 In some examples, the display unit 100 further includes an optical system 130, and a display screen 110 is located between the optical system 130 and the light guide plate 120 along the optical axis OA of the optical system 130, with the display surface 113 of the display screen 110 facing the optical system 130. For example, the optical system 130, the display screen 110 and the light guide plate 120 are all located in the extension direction of the optical axis OA.

[0099] refer to Figure 1 and Figure 6 The optical system 130 includes a lens structure 131, a transflective coating BS, a reflective polarizing layer RP, a phase retardation film QWP, and a linear polarizing film LP. The lens structure 131 includes a first surface S1 and a second surface S2 along the optical axis OA. The transflective coating BS is located between the first surface S1 and the display surface 113. The reflective polarizing layer RP is located on the second surface S2 away from the first surface S1. The phase retardation film QWP is located on the first surface S1 away from the transflective coating BS. The linear polarizing film LP is located on the reflective polarizing layer RP away from the transflective coating BS. For example, light emitted from the display surface 113 is configured to be transmitted through the transflective coating BS and then enter the lens structure 131. It is also configured to be reflected back between the transflective coating BS and the reflective polarizing layer RP before exiting, and then filtered by the linear polarizing film LP to remove stray light before entering the human eye. By setting the aforementioned reflective polarizing layer RP, phase retardation film QWP, and transflective coating BS, a folded optical path can be formed, thereby greatly reducing the space required between the human eye and the display device, making the display device smaller and thinner.

[0100] For example, the display device can be a VR display device. For example, a VR display device can be a display device employing an ultra-short-throw folded optical path. For example, the display device can be a MR display device. For example, an MR display device can be a display device employing an ultra-short-throw folded optical path.

[0101] Understandable, Figure 6 The optical system is illustrated only schematically as a pancake architecture forming a folded optical path, but this disclosure is not limited thereto. For example, the optical system could also be an architecture including Fresnel lenses, etc.

[0102] refer to Figure 6 For example, the first surface S1 can be a convex surface, and the transflective film BS can be deposited on the first surface S1.

[0103] For example, the display screen, light guide plate, and optical system in the display unit can all be housed within the housing. Alternatively, the display screen and light guide plate can be entirely housed within the housing, while a portion of the optical system can be housed within the housing and another portion can protrude outside. For example, if the first surface of the optical system is convex, a portion of the first surface can protrude outside the housing.

[0104] refer to Figure 6 For example, the transflective film BS is configured to transmit a portion of light and reflect another portion of light. For example, the transflective film may have a transmittance of 50% and a reflectance of 50%. For example, the transflective film may have a transmittance of 60% and a reflectance of 40%. For example, the transflective film may have a transmittance of 65% and a reflectance of 35%. The optical system provided in this disclosure is not limited thereto, and the transmittance and reflectance of the transflective film may be set according to product requirements.

[0105] refer to Figure 6 For example, a reflective polarization layer RP is configured to reflect linearly polarized light of one characteristic and transmit linearly polarized light of another characteristic. For instance, the reflective polarization layer functions as follows: within the plane of the film, there exists a transmission axis direction where the transmittance of the polarization component of incident light parallel to this axis (e.g., s-polarized light) is greater than the transmittance of the polarization component perpendicular to this axis (e.g., p-polarized light), and the reflectance of the polarization component parallel to this axis (e.g., s-polarized light) is less than the reflectance of the polarization component perpendicular to this axis (e.g., p-polarized light). For instance, the reflective polarization layer can also be called a polarization beam splitter. For instance, the transmittance of polarized light parallel to the transmission axis of the reflective polarization layer is not less than 85%, such as not less than 90%, such as not less than 95%, such as not less than 98%; the reflectance of polarized light perpendicular to the transmission axis of the reflective polarization layer is not less than 85%, such as not less than 90%, such as not less than 95%, such as not less than 98%.

[0106] refer to Figure 6 For example, a phase retardation film (QWP) is configured to allow transmitted light to switch between circular and linear polarization states. For example, the QWP can be a quarter-wave plate. For example, the QWP has the following characteristics: there exists a direction with the lowest refractive index and a direction with the highest refractive index within the film plane, namely the fast axis and the slow axis, respectively; polarized light parallel to the slow axis is delayed by 1 / 4 wavelength after passing through the QWP compared to polarized light parallel to the fast axis.

[0107] refer to Figure 6 For example, the phase retardation film QWP can be located between the reflective polarization layer RP and the transmissive film BS. Alternatively, the phase retardation film QWP can be located between the reflective polarization layer RP and the second surface S2.

[0108] However, this disclosure is not limited thereto. For example, if the first surface and the second surface are the surfaces of different lenses, the phase retardation film may be located between the first surface and the second surface, and the reflective polarization layer may be disposed on the second surface. For example, if the reflective polarization layer is a cholesteric liquid crystal layer, the phase retardation film may be located on the side of the reflective polarization layer away from the second surface.

[0109] refer to Figure 6 For example, the transmission axis of the linear polarizing film LP coincides with the transmission axis of the reflective polarizing layer RP. The linear polarizing film LP is used to further filter out other stray light, allowing only polarized light (such as s-polarized light) that has passed through the linear polarizing film LP to enter the human eye. For example, the material of the linear polarizing film LP may include polyvinyl alcohol (PVA) with added dichroic molecules, liquid crystal polymer film with added dichroic molecules, etc.

[0110] In some display devices, RGB color display is achieved using color filters. In the display device provided in this embodiment, the introduction of a laser light source enables color display based on timing technology, facilitating the optimization of the pixel architecture of the LCD display.

[0111] For example, without changing the RGB pixel size, RGB pixels can share a single pixel, allowing for a higher pixel aperture ratio and thus achieving higher luminous efficacy and a lower screen-door effect. Furthermore, because RGB pixels can share a single pixel, a higher pixel density can be achieved, improving screen resolution performance within the same screen size. For instance, screen resolution can be increased from 2K to 4K, or from 3K to 6K.

[0112] The following points need to be explained:

[0113] (1) The accompanying drawings of the embodiments of this disclosure only involve the structures involved in the embodiments of this disclosure, and other structures can be referred to the general design.

[0114] (2) Where there is no conflict, features of the same embodiment and different embodiments of this disclosure may be combined with each other.

[0115] The above description is merely an exemplary embodiment of this disclosure and is not intended to limit the scope of protection of this disclosure, which is determined by the appended claims.

Claims

1. A display device, comprising: case; The display unit is at least partially disposed within the housing; The display unit includes a display screen and a light guide plate, wherein the light guide plate is located on the light-incident side of the display screen; A laser light source is disposed outside the housing; An optical fiber connects the light guide plate and the laser source. The light guide plate has its light-emitting surface facing the display screen, and the laser emitted from the laser source is configured to pass through the optical fiber and enter the light guide plate, and then enter the display screen from the light-emitting surface.

2. The display device according to claim 1, wherein, The display device includes a near-eye display device, which is configured so that only the housing is worn on the user's head.

3. The display device according to claim 2 further includes a power supply disposed outside the housing, the power supply being configured to supply power to the laser light source.

4. The display device according to claim 3 further includes a light source device disposed outside the housing, wherein the power supply and the laser light source are both disposed inside the light source device.

5. The display device according to any one of claims 1-4, wherein, The light guide plate includes a dimming layer located on the light-emitting surface, the dimming layer being configured to modulate the laser.

6. The display device according to claim 5, wherein, The dimming layer includes at least one of a microlens, a surface relief grating, a holographic grating, and a metasurface.

7. The display device according to claim 5, wherein, The display screen is a liquid crystal display screen, and the display screen includes a black matrix that defines multiple pixel openings; The dimming layer includes a microstructure region, which is configured to correspond one-to-one with a corresponding number of the plurality of pixel openings, and the orthographic projection of the pixel openings on the display surface of the display screen at least partially overlaps with the orthographic projection of the microstructure region on the display surface; the microstructures within the microstructure region are configured to modulate the laser.

8. The display device according to claim 7, wherein, At least one of the microstructure regions has a line connecting the center of its corresponding pixel opening perpendicular to the display surface.

9. The display device according to claim 7, wherein, The outer contour of the orthographic projection of the microstructure region on the display surface coincides with the outer contour of the orthographic projection of the pixel opening on the display surface.

10. The display device according to any one of claims 1-4, wherein, The display unit further includes an optical system, and the display screen is located between the optical system and the light guide plate along the optical axis of the optical system, with the display surface of the display screen facing the optical system; The optical system includes a lens structure, a transmissive coating, a reflective polarizing layer, a phase retardation film, and a linear polarizing film; the lens structure includes a first surface and a second surface along the optical axis. The transflective film is located between the first surface and the display surface, the reflective polarization layer is located on the second surface away from the first surface, the phase retardation film is located on the first surface away from the transflective film, and the linear polarization film is located on the reflective polarization layer away from the transflective film.

11. The display device according to any one of claims 1-4, wherein, The laser source includes at least two backlights configured to emit lasers of different colors.

12. The display device according to claim 11, wherein, The laser source includes a first backlight configured to emit red laser light, a second backlight configured to emit green laser light, and a third backlight configured to emit blue laser light. The lasers emitted by the first backlight, the second backlight, and the third backlight are configured to mix in the optical fiber to form white light.

13. The display device according to any one of claims 1-4 further includes a speckle eliminator disposed outside the housing, the speckle eliminator being connected between the optical fiber and the laser light source.

14. The display device according to claim 13 further includes a light source device disposed outside the housing, wherein both the speckle eliminater and the laser light source are disposed inside the light source device.

15. The display device according to any one of claims 1-4, wherein, The optical fiber is a multimode optical fiber.

16. The display device according to any one of claims 1-4, wherein, The laser emitted from the laser source is polarized light.

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