Optical-electrical separation type pico projection optical structure based on image transmission optical fibers

Abstract

Provided in the present invention is an optical-electrical separation type pico projection optical structure based on image transmission optical fibers. The structure is mainly composed of a display module, an optical module and an image transmission module, wherein the display module is composed of one or more micro-display chips, and a drive and a power source part of each micro-display chip; the optical module is an image-space telecentric pico projection lens composed of at least one spherical or non-spherical lens; and the image transmission module is composed of an optical fiber bundle formed by a large number of image transmission optical fibers arranged in an array, and a micro-collimation element array added when necessary. In the present invention, by means of combining the micro-display chips, the image transmission optical fibers and the pico projection lens, a pico projection structure in which an optical module is effectively separated from an electrical module is realized. The pico projection structure can be applied to near-eye display devices such as a smart helmet and smart glasses, greatly enhancing the structural flexibility of the pico projection structure; in addition, the pico projection structure is more suitable for use in special environments with relatively large effects on electronic devices, such as an underwater environment and a strong magnetic field.

Description

A photoelectric separation micro-projection optical structure based on image transmission fiber Technical Field

[0001] The present invention relates to the technical field of micro-projection and near-eye display, in particular to a photoelectric separation type micro-projection optical structure based on image transmission optical fiber. Background Art

[0002] Pico Projection: A miniaturized projection technology that uses high-brightness LED or laser light sources to project images or videos onto a screen or other surface. Pico projectors are typically small, portable, and flexible, suitable for a variety of environments and applications. They can also be connected to various devices, such as smartphones, tablets, or laptops, for a convenient projection experience.

[0003] Near-Eye Display (NED) is a display technology that projects images or information directly in front of the user through a head-mounted display, smart glasses, or other portable devices, creating an immersive virtual reality (VR) or augmented reality (AR) experience. This technology enables users to see virtual objects or overlay them with real-world information, greatly expanding the user's perceptual interface.

[0004] Traditional micro-projectors primarily rely on LEDs or lasers as light sources, utilizing technologies such as DLP, LCoS, and LBS to achieve projection display. Since the light source and image source are generated by different devices, the structure has significant limitations, preventing traditional micro-projectors from achieving true miniaturization. However, using self-luminous display chips such as Micro LEDs and Micro OLEDs to replace the light source and image source can greatly simplify the structure, providing a better approach for miniaturization of projection. When traditional micro-projectors are applied to near-eye display devices, they also face limitations such as large size and inflexible structure. Furthermore, in some special usage environments, such as underwater and in strong magnetic fields, which have a significant impact on electronic components, the near-eye display devices require special waterproofing and anti-magnetic treatments, which are costly and difficult, and will further increase the structural volume, significantly reducing ease of use and comfort. Technical issues

[0005] In view of this, the purpose of the present invention is to provide a photoelectric separation micro-projection optical structure based on image transmission optical fiber, which can be applied to near-eye display devices such as smart helmets and smart glasses. While greatly enhancing its structural flexibility, it is also more suitable for use in special environments such as underwater and strong magnetic fields that have a greater impact on electronic devices. Technical Solutions

[0006] To achieve the above objectives, the present invention adopts the following technical solution: comprising a display module, an image transmission module, and an optical module; the source image or video of the display module passes through the image transmission module and the optical module, and is finally observed with the screen as the image plane;

[0007] The display module is composed of one or more micro-display chips and their driving and power supply parts. When the optical structure can only display monochrome images, the display module is composed of one monochrome micro-display chip and its driving and power supply parts. When the optical structure can display full-color images, the display module is composed of one full-color micro-display chip and its driving and power supply parts, or is composed of three monochrome micro-display chips and their driving and power supply parts.

[0008] The optical module is at least one micro-projection lens composed of a spherical surface, an aspherical surface, a Fresnel lens or other geometric optical elements, or a micro-nano optical element with imaging capabilities such as a metasurface. The micro-projection lens projects the image onto a physical screen.

[0009] The image transmission module is composed of a large number of optical fibers bundled and arranged in an array. A micro-collimation element array is placed before the display pixels. One micro-collimation element corresponds to one optical fiber, or a single micro-collimation element covers multiple optical fibers. Each optical fiber is responsible for transmitting the information of a single pixel or a collection of pixels. The micro-collimation element array serves as the optical coupling element, but other elements such as metasurfaces, gratings, and liquid crystal lenses can also be used in its place.

[0010] In a preferred embodiment, the micro-display chip in the display module is used to generate a micro-display image source. When the structure can only display monochrome images, the image is generated by a monochrome micro-display chip, wherein each luminous pixel or multiple luminous pixels are transmitted to the optical module through a group of micro-collimation elements and an optical fiber; when the structure can display full-color images, the image is generated by a single full-color micro-display chip, or by three monochrome micro-display chips; when the system image is generated by a single full-color micro-display chip, every three adjacent color luminous sub-pixels constitute a complete pixel, and the three sub-pixels are respectively transmitted through A set of micro-collimation elements and an optical fiber are transmitted to the optical module, or a complete pixel is transmitted to the optical module through the same set of micro-collimation elements and the same optical fiber; when the system image is generated by three monochrome micro-display chips respectively, each pixel is generated by the light-emitting pixels corresponding to the three monochrome micro-display chips, and these pixels are respectively bundled by the corresponding micro-collimation elements through the color combining element and then transmitted to the optical module through the same optical fiber, or the corresponding pixels of the three-color chips are respectively transmitted to the optical module through the corresponding micro-collimation elements and an optical fiber, and the colors and images are combined at the coupling end of the image transmission fiber.

[0011] In a preferred embodiment, the pixel shape, spacing, and resolution on the microdisplay are redefined by the image transmission fiber. When the system image is generated by a single full-color microdisplay chip, three adjacent color pixels constitute a complete pixel. The sub-pixel shapes include, but are not limited to, circular, triangular, or rectangular, and their arrangement structures include, but are not limited to, striped, triangular, mosaic, or PenTile RGBG arrangements. When the pixel diagonal length is less than the fiber core diameter, the image resolution at the outcoupling end is equal to the resolution of the image generated by the microdisplay chip after beam shaping through corresponding microcollimation elements, or after beam shaping through the same set of microcollimation elements and then transmitted to the outcoupling end through a single fiber. When the pixel diagonal length is greater than the fiber core diameter, the light emitted by a single pixel, after passing through the microcollimation elements, is coupled into multiple adjacent optical fibers. The image resolution at the outcoupling end is greater than the resolution of the image generated by the microdisplay chip, achieving super-resolution projection display.

[0012] In a preferred embodiment, the micro-projection lens of the optical module is used to project the image transmitted by the image transmission optical fiber directly onto a screen display, or project it onto a near-eye display device for entry into the eye. Its lenses include but are not limited to materials such as glass, plastic or crystal, and the lens group structure includes but is not limited to Fresnel optical surface, metasurface, folded optical path, Pancake, double glued, and active optical zoom structure; the micro-projection lens preferably has an image-side telecentric optical path structure, at which time the coupling efficiency with the image transmission optical fiber and the uniformity of the projected image are optimal; when the micro-projection lens is not an image-side telecentric optical path structure, the system images normally, but the coupling efficiency from the image transmission optical fiber to the micro-projection lens is lower than the former, and the uniformity of the projected image will also be reduced.

[0013] In a preferred embodiment, the image transmission module is used to collect image light emitted by the display chip and transmit it to the optical module, wherein the micro-collimation element adopts an array structure composed of geometric optical elements, or at least one of metasurfaces and photonic crystal diffraction optical elements, and each micro-collimation element corresponds to a light-emitting pixel one-to-one, and is used to collimate the light beam emitted by the light-emitting pixel, or one micro-collimation element covers multiple light-emitting pixels; the image transmission fiber is an integrated optical device composed of a large number of optical fibers arranged according to a certain rule; the numerical aperture of the image transmission fiber should be less than or equal to the image-side numerical aperture of the micro-projection lens in the corresponding optical module, at which time the coupling efficiency from the image transmission fiber to the micro-projection lens is the highest; when the numerical aperture of the image transmission fiber is larger than the image-side numerical aperture of the micro-projection lens in the corresponding optical module, the system can also form an image normally, but the coupling efficiency from the image transmission fiber to the micro-projection lens is lower than the former, and the uniformity of the projected image will also be reduced.

[0014] In a preferred embodiment, when the structure realizes full color through three monochrome RGB micro-display chips, they are first coupled into the optical fiber and then the colors are combined at the outcoupling end of the optical fiber bundle; or the colors are first combined through an X-prism and then coupled into the optical fiber;

[0015] When the system is such that the light output from the light-emitting pixels is collimated and then coupled into the optical fibers, and the colors are combined at the outcoupling end of the optical fiber bundle, the incoupling end of the image transmission optical fiber is divided into a first coupling end, a second coupling end, and a third coupling end, which are respectively connected to the first micro-display chip, the second micro-display chip, and the third micro-display chip of the three RGB colors, and the corresponding outcoupling end is a single-ended output, wherein the three optical fibers transmit the corresponding sub-pixels on the three chips respectively;

[0016] When the system is a system in which the light emitted by the luminous pixels is collimated, first passes through an X-prism for color combination, and then is coupled into the optical fiber, three groups of monochrome micro-display chips and their corresponding micro-collimation element arrays are respectively located on the three incident surfaces of the X-prism, and the coupling end of the image transmission optical fiber is located on the exit surface of the X-prism. The monochromatic light beams generated by the three groups of micro-display chips are collimated by the corresponding micro-collimation elements and color combined by the X-prism, and then transmitted to the optical module by the image transmission optical fiber, and finally projected onto a screen or a near-eye display device.

[0017] In a preferred embodiment, when the diagonal length of the luminous pixel is smaller than the fiber core diameter, the interval between two adjacent or two groups of luminous pixels is approximately equal to the fiber cladding diameter, the image transmission fiber array arrangement corresponds to the luminous pixel array arrangement, the luminous pixels and the optical fiber are coupled at the pixel level, and the light output of one luminous pixel is coupled into one optical fiber, or a full-color light beam consisting of three adjacent color luminous sub-pixels is coupled into one optical fiber; when the optical fiber arrangement structure in the image transmission optical fiber is inconsistent with the luminous pixel arrangement structure, or the optical fiber core diameter is not equal to the interval between two adjacent or two groups of luminous pixels, or the diagonal length of the luminous pixel is greater than the optical fiber core diameter, the luminous pixels and the optical fiber are not coupled at the pixel level, crosstalk may exist between adjacent pixels, or the projected display pixels may be incomplete, but the image can still be transmitted normally.

[0018] In a preferred embodiment, the light emitted by the micro-display chip pixel can be directly coupled to the image transmission fiber, without the need for a micro-collimation element, or it can be coupled into the image transmission fiber through a micro-collimation element to form an indirect coupling; when the two are directly coupled, the distance h between the micro-display chip and the fiber needs to be less than The coupling efficiency is optimized, where D is the core diameter and d is the pixel width. is the angle between the incident light and the optical axis; when the two are indirectly coupled, the coupling efficiency is related to the micro-collimation element. The higher the proportion of light that is incident on the optical fiber core after passing through the micro-collimation element and whose angle with the optical axis is less than the maximum incident angle of the optical fiber accounts for in the total light output, the higher the coupling efficiency between the two.

[0019] In a preferred embodiment, when applied to a direct-to-eye projection system or a head-mounted near-eye display device, the number of the optical structures is one group, which is used to output an image beam corresponding to the left eye or the right eye; or the number of the optical structures is two groups, which are divided into a left near-eye display module and a right near-eye display module, which are respectively used to output image beams corresponding to both eyes, wherein the near-eye display structure includes but is not limited to a waveguide, a free-form surface, and a 4f system; wherein the optical module is installed on the near-eye display device, which is used to output an image beam into the human eye, and the display module is installed on a portable or fixed device, which is used to generate an image and provide power, and the two are connected through an image transmission module to achieve effective separation of the optical module and the electrical module, which is more suitable for special environments such as underwater and strong magnetic fields that have a greater impact on electronic devices.

[0020] In a preferred embodiment, when used underwater or in a strong magnetic field environment, the image-transmitting optical fiber and the micro-projection lens are positioned and fixed in a special manner to prevent the imaging effect from being affected by factors such as water flow, pressure, or vibration in the underwater environment. The special manner includes, but is not limited to: using a water-resistant and pressure-resistant protective sleeve around the image-transmitting optical fiber and the micro-projection lens, using waterproof adhesives or magnetic elements at or around their bottom to fix them to the support structure, and using vibration-absorbing materials such as springs around them to reduce the impact of external vibrations on them; secondly, the optical module is made of water-pressure-resistant and corrosion-resistant materials, and remains reliable and stable after water intrusion in an underwater environment; at the same time, the optical module and the part connected to the image-transmitting optical fiber should adopt a detachable structure, which can be easily disassembled after use or when needed to remove dirt, sediment, or other contaminants.

[0021] In a preferred embodiment, the optical structure can be combined with a traditional fiber optic scanning device to achieve imaging on a screen or near-eye display device through the persistence of vision effect of the human eye. A fiber optic scanning structure is added to the outcoupling end of the image transmission fiber as a vibration source. The electrodes of the vibration source are divided into four parts according to the cross orientation. By applying a potential to each electrode, it can be driven separately in the X-axis and Y-axis directions. Vibrations of a resonant frequency with a 90° phase difference are added in the X-axis direction and the Y-axis direction, and a spiral trajectory is drawn as the amplitude gradually increases. Compared with the single-pixel scanning imaging of a traditional single optical fiber, this structure uses an optical fiber bundle to achieve surface pixel scanning imaging, which greatly improves the image transmission rate, imaging size and resolution. Beneficial effects

[0022] Compared with the existing technology, the present invention has the following beneficial effects: by combining a self-luminous micro-display chip, an image transmission optical fiber and a micro-projection lens, a micro-projection structure with an effectively separated optical module and electrical module is realized. When it is applied to near-eye display devices such as smart helmets and smart glasses, the optical module is installed on the near-eye display device to output an image light beam into the human eye. The display module can be installed on a portable or fixed device to generate images, provide power, etc. The two are connected through the image transmission module, which greatly enhances its flexibility and is also more suitable for use in special environments such as underwater and strong magnetic fields that have a greater impact on electronic devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIG1 is a schematic structural diagram of an embodiment of the present invention.

[0024] FIG2 is a schematic structural diagram of a second embodiment of the present invention.

[0025] FIG3 is a schematic structural diagram of a third embodiment of the present invention.

[0026] FIG4 is a schematic diagram of the pixel structure of the optical fiber outcoupling end according to the third embodiment of the present invention.

[0027] FIG5 is a schematic diagram of a structure of an embodiment of the present invention applied to a near-eye display.

[0028] FIG6 is a schematic diagram of a structure of an embodiment of the present invention applied to a near-eye display.

[0029] FIG7 is a schematic diagram of a structure of an embodiment of the present invention applied to a near-eye display.

[0030] FIG8 is a schematic diagram of a flow chart of an embodiment of the present invention

[0031] Description of the accompanying drawings:

[0032] Figure 1: 101: Microdisplay chip, 102: Microcollimation element array, 103: Image transmission fiber, 104: Image transmission fiber coupling end, 105: Image transmission fiber coupling end, 106: Cross section of image transmission fiber coupling end, 107: Microprojection lens, 108: Projection light;

[0033] Figure 2: 1011: First micro-display chip, 1012: Second micro-display chip, 1013: Third micro-display chip, 1021: First micro-collimation element array, 1022: Second micro-collimation element array, 1023: Third micro-collimation element array, 103: Image transmission fiber, 104: Image transmission fiber coupling end, 105: Image transmission fiber coupling end, 106: Cross section of image transmission fiber coupling end, 107: Micro-projection lens, 108: Projection light, 109: X-color combining prism;

[0034] Figure 3: 1011: First microdisplay chip, 1012: Second microdisplay chip, 1013: Third microdisplay chip, 1021: First microcollimation element array, 1022: Second microcollimation element array, 1023: Third microcollimation element array, 103: Image transmission fiber, 1041: First coupling end of image transmission fiber, 1042: Second coupling end of image transmission fiber, 1043: Third coupling end of image transmission fiber, 105: Out-coupling end of image transmission fiber, 106: Cross section of out-coupling end of image transmission fiber, 107: Microprojection lens, 108: Projection light;

[0035] Figure 4: 1061: Stripe arrangement; 1062: Delta arrangement; 1063: Mosaic arrangement; 1064: PenTile RGB arrangement;

[0036] Figure 5: 201: Left micro-projection system, 202: Right micro-projection system, 203: Left near-eye display module, 204: Right near-eye display module;

[0037] Figure 6: 201: left micro-projection system, 202: right micro-projection system, 205: left near-eye display module, 206: right near-eye display module;

[0038] Figure 7: 201: Left micro-projection system, 202: Right micro-projection system, 207: Left near-eye display module, 208: Right near-eye display module, 2071: Lens group, 2072: Total reflection sheet, 2073: Lens group, 2074: Flat beam splitter, 2081: Lens group, 2082: Total reflection sheet, 2083: Lens group, 2084: Flat beam splitter. Modes for Carrying Out the Invention

[0039] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0040] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present application belongs.

[0041] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application; as used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form, and it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or their combinations. Example

[0042] As shown in FIG1 , the present invention provides a photoelectrically separated self-luminous micro-projection optical structure based on an image transmission fiber. This structure comprises three major parts, from the display image source to the screen or the human eye, namely, a display module, an image transmission module, and an optical module. The display module comprises a micro-display chip 101 capable of generating a micro-display image, and its drive and power supply parts. The image transmission module is located between the display module and the optical module, and is mainly composed of a large number of image transmission fibers 103 that are bundled and arranged in an array. To enhance the fiber bundling capability, a micro-collimation element array 102 is added between the micro-display chip 101 and the coupling end of the image transmission fiber, wherein a group of micro-collimation elements corresponds to one optical fiber responsible for transmitting one pixel. The optical module is an image-side telecentric micro-projection lens 107 composed of at least three spherical or aspherical lenses. The optical module is installed on the near-eye display device to output the image light beam into the human eye or directly project the image onto the screen. The display module can be installed on a portable or fixed device to generate images, provide power, etc. The two are connected through the image transmission module to achieve effective separation of the optical module and the electrical module, which is more suitable for special environments such as underwater and strong magnetic fields that have a greater impact on electronic devices.

[0043] The microdisplay chip 101 of this embodiment is used to generate microdisplay images, including but not limited to self-luminous display chips such as Micro-LED and Micro-OLED. It can also be replaced by other passive light-emitting structures capable of generating microdisplay images, such as LCOS, LCD, and DMD. Furthermore, the microdisplay chip 101 can be a monochrome or full-color self-luminous display chip. When this embodiment is only capable of displaying monochrome patterns, each light-emitting unit on the microdisplay chip 101 is responsible for a pixel, and each pixel corresponds to a micro-collimation element in the micro-collimation element array 102. The emitted light beam is collimated and then transmitted to the optical module via an optical fiber in the image transmission fiber 103. Similarly, when this embodiment can display a full-color pattern, every three adjacent color light-emitting pixels on the micro-display chip 101 constitute a complete pixel. One complete pixel can correspond to one micro-collimation element in the micro-collimation element array 102, and the emitted light beam can be collimated and then transmitted to the optical module through one optical fiber in the image transmission optical fiber 103; or three adjacent color pixels can correspond to three adjacent micro-collimation elements in the collimation element array 102, and the emitted light beam can be collimated and then transmitted to the optical module through three adjacent optical fibers in the image transmission optical fiber 103.

[0044] The image transmission module of this embodiment is used to collect image light emitted by the display chip and transmit it to the optical module. It consists of two parts: a micro-collimating element array 102 and an image transmission fiber 103. The micro-collimating element array 102 is used to collimate the light beams emitted by the light-emitting pixels. It uses an array structure composed of at least one of geometric optical elements such as microlenses, TIR lenses, and reflective cups, or diffractive optical elements such as metasurfaces and photonic crystals, with each micro-collimating element corresponding one-to-one to a light-emitting pixel. The image transmission fiber 103 transmits images through the spatial transmission and variation of light energy. Its material can be quartz, glass, or plastic. The end face structure of each fiber at the image transmission fiber coupling end 105 and the image transmission fiber coupling end 106 is primarily circular, but can also be elliptical or polygonal. The end face profile reshapes the pixel outline of the projection screen or the eye.

[0045] The micro-projection lens 107 of this embodiment is used to project the image transmitted by the image transmission optical fiber onto a screen or a near-eye display device. Its lens can be made of glass, plastic, or crystal materials. The lens group structure includes but is not limited to Fresnel optical surface, metasurface, folded optical path, Pancake, double glued, active optical zoom structure, etc.

[0046] The projection lens constructed in this embodiment can project images directly onto a physical screen. When used directly with the human eye, this system can be further combined with subsequent optical systems to form a near-eye display structure that directly enters the eye. Figures 5-7 illustrate three classic near-eye display structures incorporating this embodiment. The left micro-projection system 201 and the right micro-projection system 202 are projection optical structures designed in this embodiment. Figure 5 illustrates a structure that combines waveguides to achieve near-eye display, Figure 6 illustrates a structure that combines free-form prisms to achieve near-eye display, and Figure 7 illustrates a structure that combines a 4f system to achieve retinal projection.

[0047] The working process of the optical structure is shown in FIG8 , and the specific working status is as follows:

[0048] When the optical device is activated, the micro-display chip 101 generates a micro-display image, which is collimated by the micro-collimation element array and then enters the image transmission fiber coupling end 104. After being spatially transmitted through the image transmission fiber 103, it is transmitted out of the image transmission fiber coupling end 105 and enters the micro-projection lens 107. Finally, it is directly projected onto a physical screen or enters the human eye through a near-eye display structure. Example

[0049] As shown in FIG2 , the present invention provides an optical structure for a self-luminous micro-projection using photoelectric separation based on image transmission fiber. This structure comprises three major components, from the display image source to the screen or human eye: a display module, an image transmission module, and an optical module. The display module comprises a first micro-display chip 1011, a second micro-display chip 1012, a third micro-display chip 1013, and their drive and power supply components, capable of generating a micro-display image. The image transmission module, located between the display module and the optical module, primarily comprises a large number of image transmission fibers 103 bundled and arranged in an array. To achieve full color through three monochrome micro-display chips and enhance fiber bundling capabilities, a first micro-collimating element array 1021, a second micro-collimating element array 1022, a third micro-collimating element array 1023, and an X-color combining prism 109 are interposed between the first micro-display chip 1011, the second micro-display chip 1012, and the third micro-display chip 1013 and the coupling end of the image transmission fiber. The optical module comprises an image-side telecentric micro-projection lens 107 composed of at least three spherical or aspherical lenses. The optical module is installed on the near-eye display device to output the image light beam into the human eye or directly project the image onto the screen. The display module can be installed on a portable or fixed device to generate images, provide power, etc. The two are connected through the image transmission module to achieve effective separation of the optical module and the electrical module, which is more suitable for special environments such as underwater and strong magnetic fields that have a greater impact on electronic devices.

[0050] In this embodiment, the first microdisplay chip 1011, the second microdisplay chip 1012, and the third microdisplay chip 1013 are used to generate microdisplay images. These include, but are not limited to, self-luminous display chips such as Micro-LEDs and Micro-OLEDs. Other passive light-emitting structures capable of generating microdisplay images, such as LCOS, LCDs, and DMDs, can also be substituted. The first microdisplay chip 1011, the second microdisplay chip 1012, and the third microdisplay chip 1013 are monochrome microdisplay chips for RGB colors, respectively. Each light-emitting unit is responsible for a pixel, and each pixel corresponds to a microcollimation element in the first microcollimation element array 1021, the second microcollimation element array 1022, and the third microcollimation element array 1023. The emitted light beam, after being collimated by the microcollimation element array and combined by the X-color combining prism, is transmitted to the optical module via one of the image transmission fibers 103.

[0051] The image transmission module of this embodiment is used to collect image light emitted by the display chip and transmit it to the optical module. It consists of five components: a first micro-collimation element array 1021, a second micro-collimation element array 1022, a third micro-collimation element array 1023, a color combining prism 109, and an image transmission fiber 103. The three micro-collimation element arrays are used to collimate the light beams emitted by the light-emitting pixels. They utilize an array structure composed of at least one of geometric optical elements such as microlenses, TIR lenses, and reflective cups, or diffractive optical elements such as metasurfaces and photonic crystals. Each micro-collimation element corresponds one-to-one to a light-emitting pixel. The color combining prism 109 combines the collimated three-color micro-display image to form a full-color micro-display image. The image-transmitting optical fiber 103 transmits images through the spatial transmission and change of light energy. Its material can be quartz, glass or plastic. The end face structure of each optical fiber in the image-transmitting optical fiber coupling end 105 and the image-transmitting optical fiber coupling end 106 is mainly circular, but can also be elliptical or polygonal. Its end face profile will reshape the pixel outline of the projection screen or the eye.

[0052] The micro-projection lens 107 of this embodiment is similar to that of the first embodiment and will not be repeated here.

[0053] The projection lens constructed in this embodiment can directly project an image onto a physical screen or be used directly with the human eye. Its structure is similar to that of embodiment 1 and will not be repeated here.

[0054] The working process of the optical structure is shown in FIG8 , and the specific working status is as follows:

[0055] When the optical device is activated, the first micro-display chip 1011, the second micro-display chip 1012, and the third micro-display chip 1013 generate three monochromatic micro-display images (RGB). These images are collimated by the micro-collimation element array and combined by the color combining prism 109 to form a full-color micro-display image. The images then enter the image transmission fiber coupling end 104, are spatially transmitted through the image transmission fiber 103, and are then transmitted out of the image transmission fiber coupling end 105. The images then enter the micro-projection lens 107 and are finally projected directly onto a physical screen or into the human eye through a near-eye display structure. Example

[0056] As shown in FIG3 , the present invention provides a photoelectric separation type self-luminous micro-projection optical structure based on image transmission fiber. The structure includes three parts from the display image source to the screen or human eye: the display module is composed of a first micro-display chip 1011, a second micro-display chip 1012, a third micro-display chip 1013 and its driving and power supply parts that can generate micro-display images; the image transmission module is located between the display module and the optical module, and is mainly composed of a large number of optical fibers bundled and arranged in an array. The optical module is composed of a micro-fiber 103. To achieve full color through three monochrome micro-display chips and improve the fiber bundling capability, the image transmission fiber is changed from single-end coupling to three-end coupling. A first micro-collimation element array 1021, a second micro-collimation element array 1022, and a third micro-collimation element array 1023 are added between the first micro-display chip 1011, the second micro-display chip 1012, and the third micro-display chip 1013 and the coupling end of the image transmission fiber. The optical module is an image-side telecentric micro-projection lens 107 composed of at least three spherical or aspherical lenses. The optical module is installed on the near-eye display device and is used to output the image beam into the human eye or directly project the image onto a screen. The display module can be installed on a portable or fixed device and is used to generate images and provide power. The two are connected through the image transmission module, achieving effective separation of the optical module and the electrical module. This makes it more suitable for special environments such as underwater and strong magnetic fields that have a significant impact on electronic devices.

[0057] The first micro-display chip 1011, the second micro-display chip 1012, and the third micro-display chip 1013 of this embodiment are used to generate micro-display images, including but not limited to self-luminous display chips such as Micro-LED and Micro-OLED, and can also be replaced by other passive light-emitting structures that can generate micro-display images, such as LCOS, LCD, DMD, etc. The first micro-display chip 1011, the second micro-display chip 1012, and the third micro-display chip 1013 are monochrome micro-display chips of three colors, RGB, respectively. Each light-emitting unit is responsible for one pixel, and each pixel corresponds to a micro-collimation element in the first micro-collimation element array 1021, the second micro-collimation element array 1022, and the third micro-collimation element array 1023. After being collimated by the micro-collimation element array, the emitted light beams are respectively coupled into the first coupling end 1041, the second coupling end 1042, and the third coupling end 1043 of the image transmission fiber, and are color-combined at the image transmission fiber coupling end 105. The cross-sectional structure is shown as 106, that is, each complete pixel is transmitted to the optical module through the three optical fibers in the image transmission fiber 103.

[0058] The image transmission module of this embodiment is used to collect image light emitted by the display chip and transmit it to the optical module. It consists of four components: a first micro-collimating element array 1021, a second micro-collimating element array 1022, a third micro-collimating element array 1023, and an image transmission fiber 103. The three micro-collimating element arrays collimate the light beams emitted by the light-emitting pixels. They utilize an array structure composed of at least one of geometric optical elements such as microlenses, TIR lenses, and reflective cups, or diffractive optical elements such as metasurfaces and photonic crystals, with each micro-collimating element corresponding one-to-one to a light-emitting pixel. The image transmission fiber 103 transmits images through the spatial transmission and variation of light energy. Its material can be quartz, glass, or plastic. The end face of each fiber at the image transmission fiber coupling end 105 and the image transmission fiber coupling end 106 is primarily circular, but can also be elliptical or polygonal. The profile of these end faces reshapes the outline of the pixels on the projection screen or in the eye.

[0059] The micro-projection lens 107 of this embodiment is similar to that of the first embodiment and will not be repeated here.

[0060] The projection lens constructed in this embodiment can directly project an image onto a physical screen or be used directly with the human eye. Its structure is similar to that of embodiment 1 and will not be repeated here.

[0061] The working process of the optical structure is shown in FIG8 , and the specific working status is as follows:

[0062] When the optical device is activated, the first micro-display chip 1011, the second micro-display chip 1012, and the third micro-display chip 1013 generate three monochromatic micro-display images (RGB). These images are then collimated by the micro-collimation element array and coupled into the first coupling end 1041, the second coupling end 1042, and the third coupling end 1043 of the image transmission fiber, respectively. After spatial transmission through the image transmission fiber 103, the images are combined at the output end 105 of the image transmission fiber and finally enter the micro-projection lens 107 for direct projection onto a physical screen or into the human eye through a near-eye display structure.

Claims

1. An optical-electric separation type micro-projection optical structure based on image transmission optical fiber, characterized in that: It includes a display module, an image transmission module and an optical module; the source image or video of the display module passes through the image transmission module and the optical module, and is finally observed with the screen as the image plane; The display module is composed of one or more micro-display chips and their driving and power supply parts; when the optical structure can only display monochrome images, the display module is composed of one monochrome micro-display chip and its driving and power supply parts; when the optical structure can display full-color images, the display module is composed of one full-color micro-display chip and its driving and power supply parts, or is composed of three monochrome micro-display chips and their driving and power supply parts; The optical module is at least one micro-projection lens including a spherical surface, an aspherical surface, a Fresnel lens geometric optical element, or a micro-nano optical element with imaging capability such as a metasurface, and the micro-projection lens projects an image onto a physical screen; The image transmission module is composed of a large number of optical fibers bundled and arranged in an array. A micro-collimation element array is added in front of the display pixel, one micro-collimation element corresponds to one optical fiber, or one micro-collimation element covers multiple optical fibers, and each optical fiber is responsible for transmitting the information of one pixel or the information of multiple pixel sets. Here, the micro-collimation element array is used as a coupling optical element, or other elements are used instead, such as metasurface, grating, and liquid crystal lens.

2. The optical structure of the photoelectric separation type micro-projection based on the image transmission fiber according to claim 1 is characterized in that: The micro-display chip in the display module is used to generate a micro-display image source. When the structure can only display monochrome images, the image is generated by a monochrome micro-display chip, wherein each luminous pixel or multiple luminous pixels are transmitted to the optical module through a group of micro-collimation elements and an optical fiber; when the structure can display full-color images, the image is generated by a single full-color micro-display chip, or by three monochrome micro-display chips; when the system image is generated by a single full-color micro-display chip, every three adjacent color luminous sub-pixels form a complete pixel, and the three sub-pixels are respectively transmitted to the optical module through a group of micro-collimation elements and an optical fiber. The image of the system is generated by three monochrome micro-display chips respectively, and each pixel is generated by the luminous pixels corresponding to the three monochrome micro-display chips respectively, and these pixels are respectively transmitted to the optical module through the same optical fiber after being bundled by the color combining element through the corresponding micro-collimation elements, or the corresponding pixels of the three-color chips are respectively transmitted to the optical module through the corresponding micro-collimation elements and an optical fiber, and the colors and images are combined at the out-coupling end of the image transmission fiber.

3. The optical structure of the photoelectric separation type micro-projection based on the image transmission fiber according to claim 1 is characterized in that: The pixel shape, spacing and resolution on the micro display screen are redefined by the image transmission optical fiber; when the system image is generated by a single full-color micro display chip, the three adjacent color luminous pixels constitute a complete pixel, and the shape of the sub-pixel includes a circle, a triangle or a rectangle, and its arrangement structure includes a stripe arrangement, a triangle arrangement, a mosaic arrangement or a PenTile RGBG arrangement; when the pixel diagonal length is less than the diameter of the optical fiber core, it is transmitted to the coupling end by one optical fiber after beam shaping through the corresponding micro-collimation elements, or is transmitted to the coupling end by one optical fiber after beam shaping through the same group of micro-collimation elements. At this time, the image resolution at the coupling end is equal to the resolution of the image generated by the micro display chip; when the pixel diagonal length is greater than the diameter of the optical fiber core, the light emitted by a luminous pixel passes through the micro-collimation element and is coupled into multiple adjacent optical fibers accordingly. The image resolution at the coupling end will be greater than the resolution of the image generated by the micro display chip, realizing super-resolution projection display.

4. The optical structure of the photoelectric separation type micro-projection based on the image transmission fiber according to claim 1 is characterized in that: The micro-projection lens of the optical module is used to project the image transmitted by the image transmission optical fiber directly onto the screen for display, or onto a near-eye display device for entry into the eye. The lens includes glass, plastic or crystal materials, and the lens group structure includes Fresnel optical surface, metasurface, folded optical path, Pancake, double gluing, and active optical zoom structure. The micro-projection lens preferably has an image-side telecentric optical path structure, at which time the coupling efficiency with the image transmission optical fiber and the uniformity of the projected image are optimal. When the micro-projection lens is not an image-side telecentric optical path structure, the system forms an image normally, but the coupling efficiency from the image transmission optical fiber to the micro-projection lens is lower than the former, and the uniformity of the projected image will also be reduced.

5. The optical structure of photoelectric separation type micro-projection based on image transmission fiber according to claim 1, characterized in that: The image transmission module is used to collect the image light emitted by the display chip and transmit it to the optical module, wherein the micro-collimation element adopts an array structure composed of at least one of geometric optical elements, or metasurfaces, and photonic crystal diffraction optical elements, and each micro-collimation element corresponds to a light-emitting pixel one by one, and is used to collimate the light beam emitted by the light-emitting pixel, or one micro-collimation element covers multiple light-emitting pixels; the image transmission optical fiber is an integrated optical device composed of a large number of optical fibers arranged according to a certain rule; the numerical aperture of the image transmission optical fiber should be less than or equal to the image-side numerical aperture of the micro-projection lens in the corresponding optical module, and at this time, the coupling efficiency from the image transmission optical fiber to the micro-projection lens is the highest; When the numerical aperture of the image transmission fiber is larger than the image side numerical aperture of the micro-projection lens in the corresponding optical module, the system can also form an image normally, but the coupling efficiency from the image transmission fiber to the micro-projection lens is lower than the former, and the uniformity of the projected image will also be reduced.

6. The optical structure of photoelectric separation type micro-projection based on image transmission fiber according to claim 1 or 2, characterized in that: When the structure realizes full color through three monochromatic RGB micro display chips, they are first coupled into the optical fiber and then the color is combined at the coupling end of the optical fiber bundle; or the color is combined through an X-prism and then coupled into the optical fiber; When the light from the light-emitting pixels of the system is collimated and then coupled into the optical fiber respectively, and the color is combined at the coupling end of the optical fiber bundle, the coupling end of the image transmission optical fiber is divided into a first coupling end, a second coupling end, and a third coupling end, which are respectively connected to the first micro-display chip, the second micro-display chip, and the third micro-display chip of RGB colors, and the corresponding coupling end is a single-ended output, wherein the three optical fibers transmit the corresponding sub-pixel points on the three chips respectively; When the system is a system in which the light emitted by the light-emitting pixel is collimated, first passes through an X-prism for color combination and then is coupled into an optical fiber, three groups of monochrome micro-display chips and their corresponding micro-collimation element arrays are respectively located on the three incident surfaces of the X-prism, and the coupling end of the image transmission optical fiber is located on the exit surface of the X-prism. The monochrome light beams generated by the three groups of micro-display chips are collimated by the corresponding micro-collimation elements and combined by the X-prism, and then transmitted to the optical module by the image transmission optical fiber, and finally projected onto a screen or a near-eye display device; When the diagonal length of the luminous pixel is smaller than the core diameter of the optical fiber, the interval between two adjacent or two groups of luminous pixels is approximately equal to the diameter of the optical fiber cladding, the arrangement of the image transmission optical fiber array corresponds to the arrangement of the luminous pixel array, the luminous pixels and the optical fiber are coupled at the pixel level, and the light output of one luminous pixel is coupled into one optical fiber, or a full-color light beam consisting of a group of three adjacent color luminous sub-pixels is coupled into one optical fiber; when the optical fiber arrangement structure in the image transmission optical fiber is inconsistent with the luminous pixel arrangement structure, or the optical fiber core diameter is not equal to the interval between two adjacent or two groups of luminous pixels, or the diagonal length of the luminous pixel is greater than the core diameter of the optical fiber, the luminous pixel and the optical fiber are not coupled at the pixel level, crosstalk may exist between adjacent pixels or the projection display pixels may be incomplete, but the image can still be transmitted normally.

7. The optical structure of photoelectric separation type micro-projection based on image transmission fiber according to claim 1, characterized in that: The light emitted by the micro-display chip pixel is directly coupled to the image transmission fiber, and no micro-collimation element is required at this time, or it is coupled into the image transmission fiber through the micro-collimation element to form an indirect coupling; when the two are directly coupled, the distance h between the micro-display chip and the optical fiber needs to be less than The coupling efficiency is optimal, where D is the core diameter and d is the pixel width. is the angle between the incident light and the optical axis; When the two are indirectly coupled, the coupling efficiency is related to the micro-collimation element. The higher the proportion of light that is incident on the optical fiber core after passing through the micro-collimation element and whose angle with the optical axis is less than the maximum incident angle of the optical fiber accounts for in the total light output, the higher the coupling efficiency between the two.

8. The optical structure of photoelectric separation type micro-projection based on image transmission fiber according to claim 1, characterized in that: When applied to a direct-to-eye projection system or a head-mounted near-eye display device, the number of the optical structures is one group, which is used to output an image beam corresponding to the left eye or the right eye; or the number of the optical structures is two groups, which are divided into a left near-eye display module and a right near-eye display module, which are respectively used to output image beams corresponding to both eyes, wherein the near-eye display structure includes a waveguide, a free-form surface, and a 4f system; The optical module is installed on the near-eye display device to output the image light beam into the human eye, and the display module is installed on a portable or fixed device to generate images and provide power. The two are connected through the image transmission module to achieve effective separation of the optical module and the electrical module, which is more suitable for special environments such as underwater and strong magnetic fields that have a greater impact on electronic devices.

9. The optical structure of the photoelectric separation type micro-projection based on the image transmission fiber according to claim 8 is characterized in that: When used in underwater or strong magnetic field environments, the image transmission optical fiber and the micro-projection lens are positioned and fixed in a special way to prevent the imaging effect from being reduced by factors such as water flow, pressure or vibration in the underwater environment. The special methods include: using water-resistant and pressure-resistant protective sleeves around the image transmission optical fiber and the micro-projection lens, using waterproof adhesives or magnetic elements at the bottom or around them to fix them to the supporting structure, and using vibration absorbing materials such as springs around them to reduce the impact of external vibrations on them; secondly, the optical module is made of water pressure-resistant and corrosion-resistant materials, and still has reliability and stability after water intrusion in the underwater environment; at the same time, the optical module and the part connected to the image transmission optical fiber should adopt a detachable structure, which can be easily disassembled after use or when needed to remove dirt, sediment or other contaminants.

10. The optical structure of photoelectric separation type micro-projection based on image transmission fiber according to claim 1, characterized in that: This optical structure is combined with a traditional fiber optic scanning device to achieve imaging on a screen or a near-eye display device through the persistence of vision effect of the human eye; an optical fiber scanning structure is added to the outcoupling end of the image transmission fiber as a vibration source, and the electrodes of the vibration source are divided into four parts according to a cross orientation. By applying a potential to each electrode, it is driven separately in the X-axis and Y-axis directions; vibrations of a resonant frequency with a phase difference of 90° are added in the X-axis direction and the Y-axis direction, and a spiral trajectory is drawn as the amplitude gradually increases.

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