Opto-electric separation display device structure

Abstract

The application discloses an opto-electric separation display device structure, which comprises an electrically driven display module arranged at a far end, an audio processing circuit and a driving circuit, a passive optical projection module, an image transmission fiber bundle, and a projection lens, an acousto-optic module and an ambient light acquisition module, wherein the optical projection module does not comprise any metal element, the image transmission fiber bundle is connected with the display module and the optical projection module, the fiber array of the image transmission fiber bundle is divided into an ambient light sensing area, an image transmission area and a sound transmission area, and opaque isolation layers are arranged between different transmission areas, the projection end of the ambient light sensing fiber is used for collecting ambient light and returning the ambient light in the form of light, the display module dynamically adjusts the output brightness and / or white balance of the display chip according to the compensated ambient light signal, the audio processing circuit, the sound transmission fiber and the acousto-optic module are used for generating sound output at the projection end and returning the ambient sound at the projection end to the display end.

Description

Technical Field

[0001] This invention relates to the field of displays, and in particular to a structure for a photoelectric-separated display device. Background Technology

[0002] Pico projection technology projects images onto a screen using high-brightness LEDs or laser light sources and is widely used in portable display devices. Near-eye display technology projects images directly in front of the user's eyes through head-mounted displays or smart glasses to achieve virtual reality (VR) or augmented reality (AR) experiences.

[0003] Traditional micro-projection systems typically employ technologies such as DLP, LCoS, or LBS, with separate light and image sources, resulting in complex structures and limitations in further miniaturization. In recent years, the use of self-emissive display chips such as Micro-LED and Micro-OLED to replace the separate light and image sources has provided new avenues for projection miniaturization. Building upon this, the applicant previously proposed a photoelectric separation type micro-projection optical structure based on image transmission fiber (as per patent CN117608024A). This structure places the display module (including the micro-display chip and its driving circuit) at the far end and the purely optical projection lens at the near end, with the two connected by an image transmission fiber bundle. This solution achieves advantages such as extreme thinness, complete passivity, and waterproof and magnetic resistance at the near-eye display end, making it particularly suitable for near-eye display devices and special environments such as underwater and strong magnetic fields.

[0004] However, the aforementioned photoelectric-separated micro-projection structure has a significant drawback in practical applications: because the near end (projection end) only contains pure optical elements and lacks any ambient light sensing components, the system cannot perceive ambient lighting conditions. Specifically, when the projected image is displayed under strong ambient light, insufficient output brightness results in a blurry image; when displayed under dark ambient light, excessive output brightness causes glare and wastes power; and under different color temperature light sources, the white balance of the image is distorted, leading to poor color reproduction. This deficiency severely restricts the user experience of the photoelectric-separated micro-projection structure in dynamic lighting environments. Furthermore, the aforementioned photoelectric-separated micro-projection structure cannot achieve bidirectional audio transmission, resulting in poor interactivity during actual use.

[0005] To address the aforementioned lack of ambient light sensing, existing technologies have proposed adding independent ambient light sensors and audio devices at the near end. For example, an ambient light sensor module integrating photodiodes, filters, and signal conditioning circuits, along with speakers and microphones, is installed around the projection lens. However, this approach fundamentally conflicts with the core design philosophy of photoelectric separation micro-projection structures: the core advantage of photoelectric separation structures lies in designing the near end (display end) as a completely passive, electrical, and metal-free pure optical component, thereby achieving ultra-thinness, complete sealing, waterproofing, and anti-magnetic properties. Adding independent ambient light sensors and audio devices inevitably introduces active components (requiring power), metal wires, and additional circuitry. This not only undermines the passive characteristics of the near end but also leads to the following problems: (1) the near end's volume and weight increase significantly, weakening the thinness advantage brought by photoelectric separation; (2) the metal wires and circuitry damage the near end's waterproof sealing capability and anti-electromagnetic interference capability; (3) the sensor's own heat generation affects the near end's temperature stability; and (4) it increases system cost and assembly complexity.

[0006] In summary, how to achieve passive, high-precision, and highly reliable adaptive light adjustment and audio interaction while maintaining the core advantages of photoelectric separation micro-projection structures such as "near-end passive, ultra-thin and lightweight, waterproof and anti-magnetic" is a technical challenge that urgently needs to be solved in this field. Summary of the Invention

[0007] In view of the aforementioned deficiencies of the prior art, the technical problem to be solved by the present invention is to provide a photoelectric separation display device structure, which aims to achieve high-precision adaptive adjustment of ambient light under the premise of photoelectric separation.

[0008] To achieve the above objectives, the present invention discloses a photoelectric separation display device structure, wherein the micro-projection structure comprises: An electrically driven display module, comprising a display chip, an audio processing circuit, and a driving circuit, for generating projected images and audio information; A passive optical projection module includes a projection lens, an acoustic-optical module, and an ambient light acquisition module. The optical projection module does not contain any metal components and is used to project image light onto a target surface. The acoustic-optical module is used to convert light signals into sound signals and can also convert sound signals into light signals. The image transmission fiber bundle connects the display module and the optical projection module. The image transmission fiber bundle is composed of a fiber array containing multiple fibers. The fibers in the fiber array are divided into an ambient light sensing fiber in the peripheral ambient light sensing area, a sound transmission fiber in the sound transmission area, and an image transmission fiber in the central image transmission area. An opaque isolation layer is provided between the peripheral ambient light sensing area and the sound transmission area and the central image transmission area to block lateral crosstalk of the image light to the ambient light sensing area. The projection end of the ambient light sensing fiber on one side of the optical projection module is a hemispherical structure. This hemispherical structure increases the ambient light reception angle. The surface of the hemispherical projection end is also coated with a bandpass filter. The ambient light sensing fiber is used to collect ambient light and transmit it back to the display module in the form of light. A transmission loss compensation module is disposed on one side of the display module. It is used to inject at least two reference lights of different preset wavelengths into the ambient light sensing fiber, so that the reference lights are reflected back after being projected. Based on the power difference between the transmission and reception of the reference lights, the transmission loss rate is calculated. And the transmission loss is compensated for the acquired ambient light signal according to the transmission loss rate. The display module is configured to dynamically adjust the output brightness and / or white balance of the display chip based on the compensated ambient light signal.

[0009] Optionally, the radius of curvature of the hemispherical structure at the projection end is equal to the radius of the fiber cladding, and the diameter of the hemisphere is equal to the diameter of the fiber cladding, so as to increase the receiving angle of ambient light.

[0010] Optionally, the surface of the hemispherical structure at the projection end is further coated with an anti-reflection film, which is located between the hemispherical surface and the bandpass filter film to improve the transmittance of ambient light.

[0011] Optionally, the ambient light sensing fiber includes at least three sets, with red, green, and blue bandpass filters coated on the hemispherical surface of each projection end. The center wavelengths of the red, green, and blue bandpass filters are 650nm, 550nm, and 450nm, respectively, and the bandwidths are all ±30nm. These filters are used to measure the intensity of ambient light in the red, green, and blue bands to calculate the ambient light color temperature.

[0012] Optionally, the transmission loss compensation module includes a dichroic high reflectivity film, which is disposed on the hemispherical surface of the projection end. The dichroic high reflectivity film has a reflectivity greater than 99% for reference light wavelength and a transmittance greater than 90% for ambient light wavelength.

[0013] Optionally, the transmission loss compensation module includes a fiber Bragg grating, which is written into the projection end. The center wavelength of the fiber Bragg grating is the reference wavelength, which reflects the reference wavelength and transmits the ambient light wavelength.

[0014] Optionally, the structure further includes a crosstalk suppression module, which is disposed on one side of the display module and is used to suppress crosstalk between image light and ambient light sensing signal. The crosstalk suppression module includes a time coding and lock-in amplification structure. The time coding and lock-in amplification structure performs micro-modulation of the output brightness of the display chip at a frequency of fm and a modulation depth of less than 5%, and sets a lock-in amplifier with the modulation frequency fm as a reference to extract the components related to image light crosstalk from the return signal of the ambient light sensing fiber and subtract them from the total signal.

[0015] Optionally, the crosstalk suppression module further includes a multi-channel spatial diversity structure. The multi-channel spatial diversity structure is provided with multiple ambient light sensing optical fibers arranged at different positions in the peripheral ambient light sensing area. The output of each channel is processed by an adaptive weighted fusion algorithm, and the weights are dynamically adjusted according to the current image content, giving priority to the channel with less crosstalk.

[0016] Optionally, the sound transmission area includes a first sound sensing fiber and a second sound sensing fiber, and the optical projection module further includes a passive acousto-optic sensor and a sound sensing film. The first sound sensing optical fiber is connected to the passive acoustic-optical sensor. The first sound sensing optical fiber is used to transmit the first optical signal carrying sound information generated by the display module to the passive acoustic-optical sensor. The passive acoustic-optical sensor is used to convert the first optical signal into vibration, thereby producing sound. The second sound sensing fiber is provided with a sound sensing film at one end of the optical projection module. The sound sensing film is used to sense the sound on one side of the optical projection module and generate vibration. The second sound sensing fiber is used to transmit a fixed frequency laser pulse signal generated by the display module. After the laser pulse signal is reflected by the sound sensing film, it carries the corresponding vibration information to the display module, thereby realizing sound reception.

[0017] Optionally, the projection end of the optical projection module is configured to project in at least one of the following ways: directly onto a physical screen or curtain; directly onto the human eye to form a near-eye display; or coupled into and transmitted through an optical waveguide device and then projected onto the human eye to form an augmented reality or virtual reality display.

[0018] The beneficial effects of this invention are as follows: 1. By structurally improving a portion of the optical fiber in the image transmission fiber bundle (hemispherical end face, bandpass filter), this invention fully integrates the ambient light sensing function into the existing fiber bundle, eliminating the need for any independent sensors, active components, metal wires, or circuits at the near end. Therefore, this invention fully retains the core advantages of the original photoelectric separation architecture, such as "passive near end, extremely thin and light, completely sealable, waterproof and antimagnetic, and no heat generation," while simultaneously solving the inherent defect of traditional photoelectric separation micro-projection structures that cannot sense ambient light conditions. 2. This invention uses a hemispherical end face structure, making the receiving angle of the ambient light sensing fiber close to 180°, overcoming the limitation of the narrow receiving angle (only about 30°) of flat-end fiber, ensuring stable acquisition of ambient light regardless of the projection end's orientation. By dividing the ambient light sensing fiber into three groups and coating them with red, green, and blue bandpass filters respectively, ambient light illuminance and color temperature can be measured simultaneously, providing precise input parameters for adaptive adjustment. 3. This invention achieves crosstalk suppression while maintaining near-end passive characteristics through a multi-dimensional collaborative mechanism of spatial partitioning isolation (setting an opaque isolation layer between the image transmission area and the ambient light sensing area) and time-coded phase-locked amplification (micro-modulating the image light, extracting and subtracting crosstalk components using the modulation frequency as a reference). This solves the technical problem of high-brightness image light drowning out weak ambient light signals. 4. This invention uses a dual-wavelength reference method, injecting at least two different preset wavelengths of reference light into the ambient light sensing fiber. The transmission loss rate is calculated in real time using the power change of the reference light after reflection at the projection end, and the ambient light signal is dynamically compensated. This scheme effectively eliminates transmission loss drift caused by fiber bending, stretching, or temperature changes, ensuring the accuracy and stability of ambient light measurement during long-term use. 5. The display module dynamically adjusts the output brightness of the display chip based on the compensated ambient light level, ensuring the projected image is clearly visible in strong light and not glaring in low light. Simultaneously, it dynamically adjusts the driving gain of the red, green, and blue channels according to the ambient light color temperature, adapting the white balance of the image to different light source environments, significantly improving the user's viewing experience under dynamic lighting conditions. 5. This invention adds a sound transmission area to the image transmission fiber bundle. It utilizes a first sound sensing fiber in conjunction with a passive acousto-optic sensor to convert light signals into vibrations for sound generation, and a second sound sensing fiber in conjunction with a sound sensing film to convert vibrations into light signals for sound reception. Thus, while maintaining the core advantages of the projection end—passive, electricity-free, metal-free, waterproof, anti-magnetic, and ultra-thin—it integrates ambient light sensing, projection display, and bidirectional audio transmission functions, achieving integrated audiovisual interaction without increasing near-end volume, resisting electromagnetic interference, and supporting long-distance voice transmission. This significantly expands the applicability of the micro-projection structure in special scenarios such as near-eye display, underwater, and strong magnetic fields.In summary, while maintaining the core advantages of the photoelectric separation micro-projection structure, this invention achieves high-precision and high-reliability ambient light adaptive adjustment in an all-fiber, passive manner, providing a solution that combines interactive intelligence and environmental adaptability for near-eye display devices and micro-projection applications in special environments such as underwater and strong magnetic fields. Attached Figure Description

[0019] Figure 1 This is a front view of a photoelectric separation display device structure provided in a specific embodiment of the present invention; Figure 2 This is a schematic diagram of the cross-sectional structure of an image transmission fiber bundle provided in a specific embodiment of the present invention; Figure 3 This is a side view of the ambient light sensing fiber provided in a specific embodiment of the present invention. Detailed Implementation

[0020] This invention discloses a photoelectric separation display device structure. Those skilled in the art can refer to the content of this document and appropriately modify the technical details to achieve the desired implementation. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included in this invention. The apparatus and application of this invention have been described through preferred embodiments. Those skilled in the art can obviously make modifications or appropriate alterations and combinations to the apparatus and application described herein without departing from the content, spirit, and scope of this invention to implement and apply the technology of this invention.

[0021] The applicant's research revealed that a special optical fiber structure can be used to collect ambient light intensity, thus solving the photoelectric separation problem. However, while ambient light sensing based on image transmission fiber maintains near-end passive characteristics, it introduces new technical challenges in practical applications. Firstly, the image transmission fiber bundle simultaneously transmits high-brightness image light and weak sensing light. The image light enters the sensing channel through cladding leakage, end-face reflection, and lateral coupling, and its intensity can be millions of times higher than the ambient light signal, completely overwhelming it. Secondly, the transmission loss of the ambient light sensing fiber dynamically drifts during use due to bending, stretching, or changes in ambient temperature, causing the light intensity received at the far end to fail to accurately reflect the ambient light intensity received at the near end, resulting in measurement distortion. These problems do not exist in traditional independent active sensor solutions and are specific technical obstacles newly discovered in this field when attempting to achieve passive ambient light sensing using optical fibers.

[0022] Therefore, embodiments of the present invention provide a photoelectric separation display device structure, such as... Figure 1-3 As shown, the micro-projection structure includes: Display module 1 includes a display chip 11, an audio processing circuit, and a driving circuit, used to generate projected images and audio information; wherein, the audio processing circuit and the driving circuit are integrated into a comprehensive circuit module 12, such as... Figure 1 As shown.

[0023] The passive optical projection module 2 includes a projection lens, an acoustic-optical module, and an ambient light acquisition module. The optical projection module does not contain any metal components and is used to project image light onto a target surface. The acoustic-optical module is used to convert light signals into sound signals and can also convert sound signals into light signals. The image transmission fiber bundle 3 connects the display module 1 and the optical projection module 2 respectively. The image transmission fiber bundle 3 is composed of an optical fiber array including multiple optical fibers. The optical fibers in the optical fiber array are divided into an ambient light sensing fiber 31 located in the peripheral ambient light sensing area 32, an audio transmission area, and an image transmission fiber 33 located in the central image transmission area 34. An opaque isolation layer is provided between the peripheral ambient light sensing area 32, the audio transmission area, and the central image transmission area 34 to block the lateral crosstalk of image light to the ambient light sensing area 32. The projection end 312 of the ambient light sensing fiber 31 located on one side of the optical projection module 2 is a hemispherical structure. The hemispherical structure is used to increase the receiving angle of ambient light. The hemispherical surface of the projection end 312 is also coated with a bandpass filter film 313. The ambient light sensing fiber 31 is used to collect ambient light and transmit it back to the display module 1 in the form of light. The transmission loss compensation module is located on one side of the display module 1. It is used to inject at least two reference lights of different preset wavelengths into the ambient light sensing fiber 31, so that the reference lights are reflected back after being reflected by the projection end 312. Based on the power difference between the transmission and reception of the reference lights, the transmission loss rate is calculated. And the transmission loss is compensated for the acquired ambient light signal according to the transmission loss rate. The display module 1 is configured to dynamically adjust the output brightness and / or white balance of the display chip 11 based on the compensated ambient light signal.

[0024] It should be noted that the core architecture of this invention includes a display module 1 located at the far end, an optical projection module 2 located at the near end, and an image transmission fiber bundle 3 connecting the two. To address the problem that existing photoelectric separation structures cannot sense ambient light, this invention divides the image transmission fiber bundle 3 into an outer ambient light sensing area 32 and a central image transmission area, and sets an opaque isolation layer between the two areas to physically block lateral crosstalk of image light to the sensing area. The projection end 312 of the ambient light sensing fiber 31 is fabricated into a hemispherical structure, which allows the fiber's receiving angle to approach 180°, enabling efficient acquisition of ambient light from all directions. The bandpass filter 313 coated on the hemispherical surface achieves selective transmission of specific wavelengths, laying the foundation for subsequent color temperature measurement. Furthermore, by setting a transmission loss compensation module, dual-wavelength reference light is injected into the sensing fiber, and the transmission loss rate is calculated in real time using the difference in reflected light power. Dynamic compensation is then applied to the acquired ambient light signal, eliminating measurement errors caused by fiber bending and temperature changes. Based on the compensated ambient light signal, the display module 1 adaptively adjusts the output brightness and white balance of the display chip 11, thereby achieving high-precision ambient light sensing and adaptive adjustment of the projected image while maintaining the advantages of near-end passive, ultra-thin, waterproof and anti-magnetic photoelectric separation.

[0025] In this specific embodiment, the radius of curvature of the hemispherical structure of the projection end 312 is equal to the radius of the fiber cladding, and the diameter of the hemispherical structure is equal to the diameter of the fiber cladding, so as to increase the receiving angle of ambient light.

[0026] It should be noted that this embodiment further defines the specific geometric parameters of the hemispherical structure at the projection end 312 of the ambient light sensing fiber 31: the radius of curvature of the hemisphere is equal to the radius of the fiber cladding, and the diameter of the hemisphere is equal to the diameter of the fiber cladding. This parameter setting ensures a smooth transition between the hemispherical surface and the fiber cladding, maximizing the reception angle (close to 180°) while avoiding optical loss or mechanical strength reduction caused by structural abrupt changes, thus ensuring good consistency and repeatability of the hemispherical end face in mass production.

[0027] In this specific embodiment, the projection end 312 can also be a wedge-shaped, conical, or inclined structure.

[0028] The hemispherical surface of the projection end 312 is also coated with an anti-reflection film, which is located between the hemispherical surface and the bandpass filter film 313 to improve the transmittance of ambient light.

[0029] It should be noted that this embodiment adds an antireflection film to the hemispherical surface coating structure, and defines the antireflection film as being located between the hemispherical surface and the bandpass filter 313. The antireflection film (such as MgF2) can effectively reduce the reflection loss of ambient light on the hemispherical surface, increasing the transmittance from approximately 96% to over 99%, significantly improving the signal intensity in low-light environments. At the same time, it provides a flat, low-defect substrate for the upper bandpass filter 313, which is beneficial to the spectral stability of the filter.

[0030] In this specific embodiment, the ambient light sensing fiber 31 includes at least three sets, and the hemispherical surface of the projection end 312 of each set is coated with red, green and blue bandpass filter films 313 respectively. The center wavelengths of the red, green and blue bandpass filter films 313 are 650nm, 550nm and 450nm respectively, and the bandwidths are all ±30nm. They are used to measure the intensity of ambient light in the red, green and blue bands respectively, so as to calculate the ambient light color temperature.

[0031] It should be noted that in this embodiment, the ambient light sensing fiber 31 is configured as at least three sets, and red, green, and blue bandpass filter films 313 (center wavelengths of 650nm, 550nm, and 450nm, bandwidth ±30nm) are coated on the hemispherical surface of each set. The three sets of fibers measure the intensity of ambient light in the red, green, and blue bands respectively, and the ambient light color temperature can be obtained by calculating the ratio of the three channel signals. This scheme does not require a complex spectrometer; it achieves low-cost, high-precision color temperature measurement using only the coatings on the fiber end faces, providing a key input for white balance adaptation.

[0032] In this specific embodiment, the transmission loss compensation module includes a dichroic high reflectivity film, which is disposed on the hemispherical surface of the projection end 312. The dichroic high reflectivity film has a reflectivity greater than 99% for reference light wavelength and a transmittance greater than 90% for ambient light wavelength.

[0033] It should be noted that this embodiment provides a specific implementation of the transmission loss compensation module: a dichroic high-reflectivity film is disposed on the surface of a hemispherical structure. This film has a reflectivity greater than 99% for reference light wavelengths (e.g., 850 nm) and a transmittance greater than 90% for ambient light wavelengths (400-700 nm). Thus, reference light injected from a distant end is efficiently reflected back to the distant end on the hemispherical surface for monitoring fiber transmission loss; while ambient light is transmitted into the fiber with almost no impact. The dichroic film physically separates the reference light and ambient light, achieving simultaneous detection of two wavelengths without interference.

[0034] In this specific embodiment, the transmission loss compensation module includes a fiber Bragg grating, which is written into the projection end 312. The center wavelength of the fiber Bragg grating is the reference wavelength, which reflects the reference wavelength and transmits the ambient light wavelength.

[0035] It should be noted that this embodiment provides another specific implementation of the transmission loss compensation module: a fiber Bragg grating (FBG) is written inside the projection end 312. The center wavelength of the FBG is the same as the reference light wavelength, reflecting the reference light while maintaining transmission to ambient light. Compared with surface coating solutions, the FBG is completely embedded inside the optical fiber, without changing the end-face geometry, and has the characteristics of high wavelength selectivity and good temperature stability, making it particularly suitable for applications with strict limitations on end-face dimensions.

[0036] In this specific embodiment, the structure also includes a crosstalk suppression module, which is disposed on one side of the display module 1 and is used to suppress crosstalk of image light to ambient light sensing signal. The crosstalk suppression module includes a time coding and lock-in amplification structure. The time coding and lock-in amplification structure performs micro-modulation of the output brightness of the display chip 11 at a frequency of fm and a modulation depth of less than 5%, and sets a lock-in amplifier with the modulation frequency fm as a reference to extract the components related to image light crosstalk from the return signal of ambient light sensing fiber 31 and subtract them from the total signal.

[0037] It should be noted that this embodiment introduces a crosstalk suppression module, employing time coding and lock-in amplification techniques to further eliminate image optical crosstalk. Specifically, the output brightness of the display chip 11 is micro-modulated at a frequency of fm and a modulation depth of less than 5%. This modulation amplitude is below the human eye's perception threshold and does not affect display quality. At the remote end, the lock-in amplifier, using the same frequency fm as a reference, accurately extracts the AC components related to image optical crosstalk from the return signal of the ambient light sensing fiber 31 and subtracts them from the total signal, thereby obtaining a pure ambient light signal. This active crosstalk suppression, combined with spatial isolation, enhances the crosstalk suppression capability to over 50dB.

[0038] Furthermore, the crosstalk suppression module also includes a multi-channel spatial diversity structure. The multi-channel spatial diversity structure is equipped with multiple ambient light sensing optical fibers 31, which are arranged at different positions in the peripheral ambient light sensing area 32. The output of each channel is processed by an adaptive weighted fusion algorithm, which dynamically adjusts the weights according to the current image content and prioritizes the channel with less crosstalk.

[0039] It should be noted that this embodiment further adds a multi-channel spatial diversity structure to the crosstalk suppression module: multiple ambient light sensing fibers 31 are set and arranged at different spatial positions in the ambient light sensing area 32. The output of each channel is processed by an adaptive weighted fusion algorithm, and the weights are dynamically adjusted according to the current image content—when the brightness of a certain area of ​​the projected image is high, the weight of the sensing channel near the corresponding position is automatically reduced, and the far-end channel with less crosstalk is given priority. This scheme makes full use of the spatial redundancy of the fiber bundle, realizes spatial domain suppression of crosstalk, and further enhances the robustness of the system under complex lighting conditions.

[0040] In this specific embodiment, the sound transmission area includes a first sound sensing fiber and a second sound sensing fiber, and the optical projection module 2 also includes a passive acousto-optic sensor and a sound sensing film. The first sound sensing fiber is connected to the passive acoustic-optical sensor. The first sound sensing fiber is used to transmit the first optical signal carrying sound information generated by the display module 1 to the passive acoustic-optical sensor. The passive acoustic-optical sensor is used to convert the first optical signal into vibration, thereby producing sound. The second sound sensing fiber has a sound sensing film at one end of the optical projection module 2. The sound sensing film is used to sense the sound on one side of the optical projection module and generate vibration. The second sound sensing fiber is used to transmit a fixed frequency laser pulse signal generated by the display module 1. After the laser pulse signal is reflected by the sound sensing film, it will carry the corresponding vibration information to the display module, thereby realizing sound reception.

[0041] In this specific embodiment, the projection end of the optical projection module 2 is configured for at least one of the following projection methods: direct projection onto a physical screen or projection screen; direct projection onto the human eye to form a near-eye display; or projection onto the human eye after coupling and transmission through an optical waveguide device to form an augmented reality or virtual reality display. This embodiment of the invention improves the structure of some optical fibers in the image transmission fiber bundle 3 (hemispherical end face, bandpass filter 313), so that the ambient light sensing function is completely integrated into the existing fiber bundle, without the need to add any independent sensors, active components, metal wires, or circuits at the near end. Therefore, this embodiment of the invention fully retains the core advantages of the original photoelectric separation architecture, such as "passive at the near end, extremely thin and light, completely sealable, waterproof and anti-magnetic, and no heat generation," while solving the inherent defect of traditional photoelectric separation micro-projection structures that cannot sense ambient light conditions.

[0042] This invention employs a hemispherical end-face structure, enabling the ambient light sensing fiber 31 to have a reception angle close to 180°. This overcomes the limitation of a narrow reception angle (only about 30°) in flat-end fiber optics, ensuring that the projection end 312 can stably collect ambient light regardless of its orientation. By dividing the ambient light sensing fiber 31 into three groups and coating them with red, green, and blue bandpass filters 313 respectively, ambient light illuminance and color temperature can be measured simultaneously, providing precise input parameters for adaptive adjustment.

[0043] The embodiments of the present invention achieve crosstalk suppression while maintaining the near-end passive characteristics through a multi-dimensional collaborative mechanism of spatial partitioning isolation (an opaque isolation layer is set between the image transmission area and the ambient light sensing area 32) and time-coded phase-locked amplification (micro-modulation of the image light, extraction and subtraction of crosstalk components with the modulation frequency as a reference). This solves the technical problem of high-brightness image light drowning out weak ambient light signals.

[0044] This invention employs a dual-wavelength reference method, injecting at least two different preset wavelengths of reference light into the ambient light sensing fiber 31. The transmission loss rate is calculated in real time using the power change of the reference light after reflection from the projection end 312, and the ambient light signal is dynamically compensated. This scheme effectively eliminates transmission loss drift caused by fiber bending, stretching, or temperature changes, ensuring the accuracy and stability of ambient light measurements during long-term use.

[0045] The display module 1 dynamically adjusts the output brightness of the display chip 11 according to the compensated ambient light level, so that the projected image is clearly visible in strong light and not dazzling in low light. At the same time, it dynamically adjusts the driving gain of the red, green and blue channels according to the ambient light color temperature, so that the white balance of the image adapts to different light source environments, significantly improving the user's viewing experience under dynamic lighting conditions.

[0046] This invention, through the addition of a sound transmission area within the image transmission fiber bundle, utilizes a first sound sensing fiber in conjunction with a passive acousto-optic sensor to convert light signals into vibrations for sound generation, and a second sound sensing fiber in conjunction with a sound sensing film to convert vibrations into light signals for sound reception. Thus, while fully maintaining the core advantages of the projection end—passive, electricity-free, metal-free, waterproof, anti-magnetic, and ultra-thin—it integrates ambient light sensing, projection display, and bidirectional audio transmission functions, achieving integrated audiovisual interaction. Furthermore, it does not increase near-end volume, resists electromagnetic interference, and supports long-distance voice transmission, significantly expanding the applicability of micro-projection structures in special scenarios such as near-eye display, underwater, and strong magnetic fields.

[0047] In summary, while maintaining the core advantages of the photoelectric separation micro-projection structure, the embodiments of the present invention achieve high-precision and high-reliability ambient light adaptive adjustment in an all-fiber, passive manner, providing a solution that combines interactive intelligence and environmental adaptability for near-eye display devices and micro-projection applications in special environments such as underwater and strong magnetic fields.

[0048] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0049] The various embodiments in this specification are described in a related manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0050] The above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A photoelectric separation display device structure, characterized in that, The micro-projection structure includes: An electrically driven display module, comprising a display chip, an audio processing circuit, and a driving circuit, for generating projected images and audio information; A passive optical projection module includes a projection lens, an acoustic-optical module, and an ambient light acquisition module. The optical projection module does not contain any metal components and is used to project image light onto a target surface. The acoustic-optical module is used to convert light signals into sound signals and can also convert sound signals into light signals. The image transmission fiber bundle connects the display module and the optical projection module. The image transmission fiber bundle is composed of a fiber array containing multiple fibers. The fibers in the fiber array are divided into an ambient light sensing fiber in the peripheral ambient light sensing area, a sound transmission fiber in the sound transmission area, and an image transmission fiber in the central image transmission area. An opaque isolation layer is provided between the peripheral ambient light sensing area and the sound transmission area and the central image transmission area to block lateral crosstalk of the image light to the ambient light sensing area. The projection end of the ambient light sensing fiber on one side of the optical projection module is a hemispherical structure. This hemispherical structure increases the ambient light reception angle. The surface of the hemispherical projection end is also coated with a bandpass filter. The ambient light sensing fiber is used to collect ambient light and transmit it back to the display module in the form of light. A transmission loss compensation module is disposed on one side of the display module. It is used to inject at least two reference lights of different preset wavelengths into the ambient light sensing fiber, so that the reference lights are reflected back after being projected. Based on the power difference between the transmission and reception of the reference lights, the transmission loss rate is calculated. And the transmission loss is compensated for the acquired ambient light signal according to the transmission loss rate. The display module is configured to dynamically adjust the output brightness and / or white balance of the display chip based on the compensated ambient light signal.

2. The photoelectric separation display device structure according to claim 1, characterized in that, The radius of curvature of the hemispherical structure at the projection end is equal to the radius of the fiber cladding, and the diameter of the hemispherical structure is equal to the diameter of the fiber cladding, so as to increase the receiving angle of ambient light.

3. The photoelectric separation display device structure according to claim 1, characterized in that, The surface of the hemispherical structure at the projection end is also coated with an anti-reflection film, which is located between the hemispherical surface and the bandpass filter film to improve the transmittance of ambient light.

4. The photoelectric separation display device structure according to claim 1, characterized in that, The ambient light sensing fiber includes at least three sets, and the hemispherical surface of the projection end of each set is coated with red, green and blue bandpass filters respectively. The center wavelengths of the red, green and blue bandpass filters are 650nm, 550nm and 450nm respectively, and the bandwidths are all ±30nm. They are used to measure the intensity of ambient light in the red, green and blue bands respectively to calculate the ambient light color temperature.

5. The photoelectric separation display device structure according to claim 1, characterized in that, The transmission loss compensation module includes a dichroic high reflectivity film, which is disposed on the hemispherical surface of the projection end. The dichroic high reflectivity film has a reflectivity greater than 99% for reference light wavelength and a transmittance greater than 90% for ambient light wavelength.

6. The photoelectric separation display device structure according to claim 1, characterized in that, The transmission loss compensation module includes a fiber Bragg grating, which is written into the projection end. The center wavelength of the fiber Bragg grating is the reference wavelength, which reflects the reference wavelength and transmits the ambient light wavelength.

7. The photoelectric separation display device structure according to claim 1, characterized in that, The structure also includes a crosstalk suppression module, which is disposed on one side of the display module and is used to suppress crosstalk between image light and ambient light sensing signal. The crosstalk suppression module includes a time coding and lock-in amplification structure. The time coding and lock-in amplification structure performs micro-modulation of the output brightness of the display chip at a frequency of fm and a modulation depth of less than 5%, and sets a lock-in amplifier with the modulation frequency fm as a reference to extract the components related to image light crosstalk from the return signal of the ambient light sensing fiber and subtract them from the total signal.

8. The photoelectric separation display device structure according to claim 7, characterized in that, The crosstalk suppression module also includes a multi-channel spatial diversity structure. The multi-channel spatial diversity structure is provided with multiple ambient light sensing optical fibers, which are arranged at different positions in the peripheral ambient light sensing area. The output of each channel is processed by an adaptive weighted fusion algorithm, which dynamically adjusts the weights according to the current image content and prioritizes the channel with less crosstalk.

9. The photoelectric separation display device structure according to claim 1, characterized in that, The sound transmission area includes a first sound sensing fiber and a second sound sensing fiber, and the optical projection module also includes a passive acousto-optic sensor and a sound sensing film. The first sound sensing optical fiber is connected to the passive acoustic-optical sensor. The first sound sensing optical fiber is used to transmit the first optical signal carrying sound information generated by the display module to the passive acoustic-optical sensor. The passive acoustic-optical sensor is used to convert the first optical signal into vibration, thereby producing sound. The second sound sensing fiber is provided with a sound sensing film at one end of the optical projection module. The sound sensing film is used to sense the sound on one side of the optical projection module and generate vibration. The second sound sensing fiber is used to transmit a fixed frequency laser pulse signal generated by the display module. After the laser pulse signal is reflected by the sound sensing film, it carries the corresponding vibration information to the display module, thereby realizing sound reception.

10. The photoelectric separation display device structure according to claim 1, characterized in that, The projection end of the optical projection module is configured to project in at least one of the following ways: directly onto a physical screen or curtain; directly onto the human eye to form a near-eye display; or coupled into and transmitted through an optical waveguide device and then projected onto the human eye to form an augmented reality or virtual reality display.

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