Projection system and method based on mini led array and variable microstructure light guide

Abstract

The application belongs to the technical field of projection display, and particularly relates to a projection system and method based on a Mini LED array and a variable microstructure light guide, which comprises a light source module, a variable microstructure light guide, a projection lens and a driving control subsystem; the driving control subsystem is electrically connected with the light source module and the variable microstructure light guide, is configured to receive a high-resolution image signal and decompose the high-resolution image signal into a first control signal and a second control signal, and synchronously drive the light source module and the variable microstructure light guide; the light source module is configured to generate a low-resolution base light field in response to the first control signal; the variable microstructure light guide is configured to perform phase profile modulation on the low-resolution base light field in response to the second control signal, so as to form a high-resolution intermediate light field; and the projection lens is arranged on an out-light path of the variable microstructure light guide, and is used for amplifying and projecting the high-resolution intermediate light field to a screen.

Description

Technical Field

[0001] This invention belongs to the field of projection display technology, specifically relating to a projection system and method based on a Mini LED array and a variable microstructure light guide. Background Technology

[0002] Current mainstream projection display technologies mainly include Digital Light Processing (DLP), Liquid Crystal Display (LCD), and Liquid Crystal on Silicon (LCoS). When achieving color imaging, these technologies all face inherent technical challenges in terms of light energy utilization efficiency, system cost, or structural complexity in their optical engine architectures. Specifically, DLP technology, based on the principle of temporal color multiplexing, employs a color separation mode combining a white light source with a color wheel, or a temporal emission mode using three-color LEDs, three-color lasers, or a laser / LED hybrid light source. Color generation is achieved through temporal color separation and mixing. However, during its application, only one color of light is modulated and utilized at any given time, while other colors are either in a waiting or ineffective state, limiting light utilization and easily causing a "rainbow effect." Furthermore, it places extremely high demands on the response speed of the light source and the digital micromirror device (DMD) chip. 3LCD and LCoS... S-C technology, based on the principle of spatial color multiplexing, typically uses a white light source combined with a beam-splitting prism system to complete color separation and synthesis in the spatial domain. Its complex beam-splitting and combining optical paths result in a large system size and high cost. Furthermore, the beam-splitting prism suffers from light throughput loss and color purity degradation. Simultaneously, the optical engine assembly requires extremely high precision, making yield control difficult. 1LCD technology, based on color filters, uses a single liquid crystal panel. Each pixel consists of three sub-pixels: red (R), green (G), and blue (B). It utilizes a color filter (Color) in front of the panel. Color filters produce color, but due to their absorptive working principle—absorbing most of the other colors to display a particular color—the utilization rate of incident light is extremely low. This results in lower brightness or higher power consumption for 1LCD projectors. Furthermore, displaying different colors with three pixels inherently results in resolution loss, meaning the actual physical resolution used to display details is only one-third of the nominal resolution. This leads to insufficient image detail, making it easy to observe noticeable pixel grids when viewed up close. The use of color filters also introduces significant color crosstalk, reducing color gamut coverage. The combination of the LCD panel and the filter results in a lower light path aperture ratio, affecting overall luminous flux.

[0003] Therefore, current mainstream projection display technologies are caught in a "triple dilemma" in pursuing high luminous efficiency, high image quality, and compact structure: DLP technology sacrifices luminous efficiency in the temporal dimension; 3LCD and LCoS technologies introduce complexity and losses in the spatial dimension; and 1LCD technology suffers from fundamentally low luminous efficiency and low resolution due to material absorption. Furthermore, while Micro-LED technology has advantages such as self-illumination, high brightness, and high reliability, its direct application in high-resolution projection imaging faces challenges such as large-scale transfer difficulties, low yield, high cost, and heat dissipation, and is unlikely to be commercialized in the short term. Summary of the Invention

[0004] This invention provides a projection system and method based on a Mini LED array and a variable microstructure light guide. The system decomposes high-resolution image signals through a drive control subsystem and synchronously drives them through a dual-function module consisting of a low-resolution light source module and a dynamically adjustable variable microstructure light guide. Simultaneously, it utilizes dynamic phase profiles for wavefront modulation and spatial redistribution of light energy to collaboratively generate high-resolution projected images. This avoids dependence on existing ultra-high-density LED arrays, simplifies the projection system architecture, saves costs, and facilitates device miniaturization.

[0005] A projection system based on a Mini LED array and a variable microstructure light guide includes a light source module, a variable microstructure light guide, a projection lens, and a drive control subsystem. The drive control subsystem, which is connected to the light source module and the variable microstructure photoconductivity, is configured to receive high-resolution image signals and decompose them into a first control signal and a second control signal, and synchronously drive the light source module and the variable microstructure photoconductivity. The light source module is configured to generate a low-resolution substrate light field in response to a first control signal; The variable microstructure light guide is disposed in the light output path of the light source module; the variable microstructure light guide includes multiple micro-units, each of which is configured to respond to a second control signal and perform phase profile modulation on the low-resolution substrate light field. The projection lens is disposed on the light output path of the variable microstructure light guide and is used to amplify the high-resolution intermediate light field and project it onto the screen.

[0006] The high-resolution image signal is decomposed by the drive control subsystem and synchronously driven by the dual-function module of the light source module and the variable microstructure light guide, thereby efficiently forming a high-resolution intermediate light field. This simplifies the projection system architecture, saves costs, and facilitates device miniaturization.

[0007] Furthermore, the light source module includes a Mini-LED chip array with a physical resolution lower than the target output resolution of the high-resolution image signal, used to provide basic color and overall brightness.

[0008] By using a mature Mini-LED chip array, high-performance projection can be achieved, reducing manufacturing costs and technological risks.

[0009] Furthermore, the light source module also includes: A heat dissipation substrate, which is coupled to the Mini-LED chip array; A first driving circuit is electrically connected to the Mini-LED chip array; An optical homogenizing layer is disposed in the light output path of the Mini-LED chip array to ensure the uniformity of the light field.

[0010] By setting up an optical homogenizing layer, the uniformity of the substrate optical field is improved, thereby providing a stable incident light basis for subsequent phase modulation of the substrate optical field.

[0011] Furthermore, when the variable microstructure photoguide is a phase modulator based on liquid crystal polymer, it includes, from top to bottom, an upper transparent substrate, an upper alignment layer, a liquid crystal polymer layer, a lower alignment layer, and a lower transparent substrate. Both the upper transparent substrate and the lower transparent substrate are made of glass or optical-grade polymer material; a patterned ITO transparent electrode is integrated on the inner surface of the upper transparent substrate; and an ITO common electrode is integrated on the inner surface of the lower transparent substrate. Both the upper alignment layer and the lower alignment layer are made of polyimide material; a pretilt angle is formed between the upper alignment layer and the upper transparent substrate, and between the lower alignment layer and the lower transparent substrate, to determine the initial orientation of the liquid crystal molecules; The liquid crystal polymer layer includes ferroelectric liquid crystal or nematic liquid crystal.

[0012] By setting the variable microstructure photoguide as a phase modulator based on liquid crystal polymer, the refractive index is changed by using voltage to control the orientation of liquid crystal molecules, achieving phase modulation with high compatibility with the substrate optical field and easy integration. The overall structure is compact, which facilitates the miniaturization and thinning of the device.

[0013] Furthermore, when the variable microstructure photoguide is a phase modulator based on a MEMS micromirror array, it includes, from top to bottom, a micromirror array, a support structure, a driving electrode, and a silicon substrate. The silicon substrate on which the second driving circuit is integrated; The driving electrode is disposed on the silicon substrate; The support structure is mounted onto the silicon substrate; the support structure includes a torsion beam structure or a flexible support structure. The micromirror array is suspended above the driving electrode by the support structure; the micromirror array is configured to rotate or move vertically under the electrostatic attraction generated by the driving electrode.

[0014] By using a variable microstructure photoguide as a phase modulator based on a MEMS micromirror array, high-precision and high-response phase modulation of the substrate optical field can be achieved by electrostatically driving and controlling the physical motion of the micromirror array.

[0015] Furthermore, the projection lens includes multiple optical lenses; the projection lens is configured as either fixed-focus or zoom.

[0016] By setting up a projection lens with multiple optical lenses, it is easy to achieve accurate imaging of light of different wavelengths; setting up a fixed-focus or zoom projection lens makes it easy to adapt to different usage scenarios, thereby ensuring the projection of high-precision images.

[0017] Furthermore, the drive control subsystem includes: A signal receiving module is used to receive input high-resolution image signals; the input high-resolution image signal formats include HDMI, DisplayPort, and LVDS. The image processing module, which has a built-in FPGA chip or ASIC chip, is used to run a signal decomposition algorithm to decompose the input signal into a first control signal and a second control signal. The storage module is used to store a pre-calibrated optical energy transfer lookup table; A synchronization control module is used to ensure the synchronized driving of the light source module and the variable microstructure light guide; The power management module is used to provide control voltage.

[0018] By setting up a multi-module drive control subsystem, it is easy to decompose the high-resolution image signal into functions, ensuring that the two types of control signals are matched accordingly, thereby achieving efficient process coordination.

[0019] A method for a projection system based on a Mini LED array and a variable microstructure light guide, comprising: Acquire high-resolution image signals; The high-resolution image signal is decomposed into a first control signal and a second control signal; The first control signal is input to the light source module to generate a low-resolution substrate light field; The second control signal is input to the variable microstructure optical guide to perform phase profile modulation on the low-resolution substrate optical field and form a high-resolution intermediate optical field. A high-resolution intermediate light field is projected onto a screen using a projection lens to form a high-resolution image.

[0020] By decomposing, modulating, and projecting high-resolution image signals, the efficient conversion of high-resolution signals into clear images is achieved, facilitating high-efficiency and high-quality projection output.

[0021] Furthermore, the step of decomposing the high-resolution image signal into a first control signal and a second control signal includes: Based on the high-resolution image signal, it is downsampled to generate a low-resolution base image, which is then used as the first control signal for the control light source module. The low-resolution base image is upsampled, and the upsampled low-resolution base image is compared with the high-resolution image to calculate the image difference information. Based on a pre-calibrated optical energy transfer lookup table, image difference information is mapped into a second control signal that drives the variable microstructure photoguide.

[0022] By downsampling the high-resolution image signal, a base light field is generated to accurately reflect the overall color and brightness characteristics of the high-resolution image. By upsampling the low-resolution base image and comparing it with the high-resolution image, a second control signal is generated based on the image difference information obtained, so as to facilitate subsequent supplementary adjustments to the base light field.

[0023] Furthermore, the step of inputting the second control signal to the variable microstructure photoguide to perform phase profile modulation on the low-resolution substrate optical field to form a high-resolution intermediate optical field includes: The second control signal is input to the variable microstructure photoguide based on liquid crystal polymer. Based on the low-resolution substrate light field, the orientation distribution of liquid crystal molecules is controlled by voltage to form an effective refractive index spatial distribution. Combined with the fixed liquid crystal polymer layer thickness to generate a phase delay distribution, phase profile modulation is achieved to form a high-resolution intermediate light field. Alternatively, a second control signal can be input to a variable microstructure photoguide based on a MEMS micromirror array. Based on the low-resolution substrate optical field, the tilt angle or deformation of the micromirror surface can be controlled by electrostatic drive to generate equivalent phase modulation and achieve phase profile modulation, thereby forming a high-resolution intermediate optical field.

[0024] By using different types of variable microstructure optical guides to perform phase modulation on the low-resolution substrate optical field, the system can efficiently supplement the details of the low-resolution substrate optical field, thereby ensuring the stable generation of the high-resolution intermediate optical field and improving the system's adaptability.

[0025] The beneficial effects of this invention are as follows: This invention decomposes high-resolution image signals through a drive control subsystem and synchronously drives them using a dual-function module consisting of a light source module and a variable microstructure light guide, thereby efficiently forming a high-resolution intermediate light field. This simplifies the projection system architecture, saves costs, and facilitates device miniaturization. By decomposing, modulating, and projecting high-resolution image signals, it achieves efficient conversion from high-resolution signals to clear images, facilitating high-efficiency and high-quality projection output. Utilizing dynamic phase profiles for wavefront modulation and spatial redistribution of light energy, it achieves a functional curved surface optical design that is both flat in form and curved in spirit. This technical approach avoids the technical bottlenecks of Micro-LEDs and overcomes the low luminous efficiency of traditional projection systems, providing a novel technical solution for the projection display field. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the system structure in this invention; Figure 2 This is a schematic diagram of a variable microstructure photoguide structure based on liquid crystal polymer; Figure 3 This is a schematic diagram of a variable microstructure optical guide structure based on a MEMS micromirror array. Figure 4 This is a schematic diagram of the drive control subsystem. Figure 5 This is a flowchart of the present invention; Figure 6 This is a schematic diagram of the modulation of each micro-unit. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] It should be noted that various aspects of embodiments within the scope of the appended claims are described below. It will be apparent that the aspects described herein can be embodied in a wide variety of forms, and any particular structure and / or function described herein is merely illustrative. Based on this disclosure, those skilled in the art will understand that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects set forth herein can be used to implement the device and / or practice the method. Additionally, this device and / or method can be implemented using other structures and / or functionalities besides one or more of the aspects set forth herein.

[0029] In addition, specific details are provided in the following description to facilitate a thorough understanding of the examples, and those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0030] Example 1 Figure 1 The system shown is a projection system based on a Mini LED array and a variable microstructure light guide, including a light source module, a variable microstructure light guide, a projection lens, and a drive control subsystem. The drive control subsystem decomposes the high-resolution image signal and drives it synchronously through a dual-function module of the light source module and the variable microstructure light guide, thereby efficiently forming a high-resolution intermediate light field. This simplifies the projection system architecture, saves costs, and facilitates device miniaturization.

[0031] Specifically, the light source module is configured to generate a low-resolution substrate light field in response to a first control signal; the light source module includes: Mini-LED chip arrays consist of multiple Mini-LED chips. The physical resolution of the Mini-LED chip array is lower than the target output resolution of the high-resolution image signal. It is used to emit beams, provide basic color and overall brightness, thereby facilitating high-performance projection and reducing manufacturing costs and technical risks. In this embodiment, the size of a single Mini-LED chip ranges from 50 to 200 μm, and the pixel pitch is from 100 to 500 μm.

[0032] A heat dissipation substrate, which is coupled to a Mini-LED chip array; The first driving circuit is electrically connected to the Mini-LED chip array; An optical homogenizing layer is placed in the light output path of the Mini-LED chip array to ensure the uniformity of the light field and provide a stable incident light basis for subsequent low-resolution substrate light field phase modulation.

[0033] Specifically, the variable microstructure light guide is set in the light output path of the light source module; the variable microstructure light guide includes multiple micro units, each of which is configured to respond to a second control signal and perform phase profile modulation on the low-resolution substrate light field to form a high-resolution intermediate light field. In this embodiment, the number of micro-units is the same as the screen resolution, and each micro-unit is independently controlled by an electric field or control signal. As a full-color modulation unit, it uses the dispersion effect to selectively modulate different wavelengths. Through the formed dynamic phase profile, it redistributes spatial light energy to the incident composite light, so that the target wavelength is precisely deflected to the target and the non-target wavelength is deflected to other positions.

[0034] Among them, such as Figure 2As shown, when the variable microstructure photoguide is a phase modulator based on liquid crystal polymer, it includes, from top to bottom, an upper transparent substrate, an upper alignment layer, a liquid crystal polymer layer, a lower alignment layer, and a lower transparent substrate. By setting the variable microstructure photoguide as a phase modulator based on liquid crystal polymer, the refractive index is changed by using voltage to control the orientation of liquid crystal molecules, thereby achieving phase modulation with high compatibility with the substrate light field and easy integration. The overall structure is compact, which is conducive to the miniaturization and thinning of the device.

[0035] Both the upper and lower transparent substrates are made of glass or optical-grade polymer materials; patterned ITO transparent electrodes are integrated on the inner surface of the upper transparent substrate; and ITO common electrodes are integrated on the inner surface of the lower transparent substrate. In this embodiment, the optical-grade polymer material is polyimide.

[0036] In this embodiment, the thickness of the upper and lower transparent substrates is 0.5~1.1mm; the linewidth of the patterned ITO transparent electrode is 5~20μm, and the spacing between the patterned ITO transparent electrodes matches the target output resolution of the high-resolution image signal.

[0037] Both the upper alignment layer and the lower alignment layer are made of polyimide material; a pretilt angle is formed between the upper alignment layer and the upper transparent substrate, and between the lower alignment layer and the lower transparent substrate, to determine the initial orientation of the liquid crystal molecules; A liquid crystal polymer layer, comprising ferroelectric liquid crystal or nematic liquid crystal; In this embodiment, the thickness of the liquid crystal polymer layer ranges from 5 to 20 μm and has a high birefringence.

[0038] Among them, such as Figure 3 As shown, when the variable microstructure photoguide is used as a phase modulator based on a MEMS micromirror array, it includes a micromirror array, a support structure, a driving electrode, and a silicon substrate from top to bottom. By using the variable microstructure photoguide as a phase modulator based on a MEMS micromirror array, high-precision and high-response phase modulation of the substrate optical field can be achieved by electrostatically driving and controlling the physical movement of the micromirror array.

[0039] A silicon substrate on which a second driving circuit is integrated; The driving electrode is disposed on the silicon substrate; A support structure, which is mounted onto a silicon substrate; the support structure includes a torsion beam structure or a flexible support structure. A micromirror array is suspended above a driving electrode by a support structure; the micromirror array is configured to rotate or move vertically under the electrostatic attraction generated by the driving electrode; the micromirror array includes multiple micromirrors. In this embodiment, the micromirrors are made of aluminum or silicon; the micromirror array size ranges from 5×5 to 20×20 μm; and the optical flatness of the micromirror surface is less than [value missing]. The rotational motion tilt angle ranges from ±5° to ±12°.

[0040] Specifically, the projection lens is positioned in the light path of the variable microstructure light guide to amplify and project the high-resolution intermediate light field onto the screen.

[0041] The projection lens is configured as either fixed-focus or zoom, and it adopts an apochromatic design. Setting a fixed-focus or zoom projection lens makes it easy to adapt to different usage scenarios, thereby ensuring the projection of high-precision images.

[0042] The projection lens includes multiple optical lenses. In this embodiment, the number of optical lenses is 3 to 10, the focal length range is 10 to 50 mm, and the F-number range is 1.8 to 2.8, which is used to achieve accurate imaging of light of different wavelengths.

[0043] Specifically, such as Figure 4 As shown, the drive control subsystem, connected to the light source module and the variable microstructure photoconductivity, is configured to receive high-resolution image signals and decompose them into a first control signal and a second control signal, and synchronously drive the light source module and the variable microstructure photoconductivity; the drive control subsystem includes: The signal receiving module is used to receive input high-resolution image signals; the input high-resolution image signal formats include HDMI, DisplayPort, and LVDS. The image processing module, which has a built-in FPGA chip or ASIC chip, is used to run a signal decomposition algorithm to decompose the input signal into a first control signal and a second control signal. The storage module is used to store a pre-calibrated optical energy transfer lookup table; In this embodiment, the pre-calibrated optical power transfer lookup table adopts a hierarchical architecture, which includes L1 level fast mode matching, L2 level region optimization parameters, and L3 level complete phase profile. The pre-calibrated optical power transfer lookup table is calibrated by measuring the response of each micro-unit to different drive control voltages on a standard optical platform, and supports online learning and adaptive optimization mechanisms. After data compression, the pre-calibrated optical power transfer lookup table is stored in the external DDR memory of the main control chip or the internal BRAM of the main control chip.

[0044] Synchronization control module, which is used to ensure the synchronous driving of the light source module and the variable microstructure light guide; The power management module is used to provide control voltage.

[0045] Example 2 Based on the same technical concept, in this embodiment... Figure 5This illustrates a projection method based on a Mini LED array and a variable microstructure light guide. By decomposing, modulating, and projecting the high-resolution image signal, it achieves efficient conversion from high-resolution signal to a clear image, facilitating high-efficiency, high-quality projection output. Specifically, it includes the following steps: S1: Acquire high-resolution image signals; S2: Decompose the high-resolution image signal into a first control signal and a second control signal; S21: Based on the high-resolution image signal, it is downsampled to generate a low-resolution base image, which is then used as the first control signal for the control light source module. The expression for calculating the resolution of the low-resolution substrate image is as follows: ; In the formula, This indicates that the low-resolution substrate image is in micro-units Pixel resolution , These are the coordinate points of the micro-unit; Represents high-resolution images in micro-units Pixel resolution; Indicates the number of pixels in the pooling window. , Indicates the total number of pixels in the pooling window; S22: Upsample the low-resolution base image and compare the upsampled low-resolution base image with the high-resolution image to calculate the image difference information; In this embodiment, the upsampling process employs the nearest neighbor copying upsampling algorithm.

[0046] The expression for calculating the resolution of the intermediate image after upsampling is as follows: ; In the formula, The intermediate image of the upsampled image is represented in microcells. Pixel resolution; Indicates the scaling factor; The expression for calculating image difference information is as follows: ; In the formula, In micro-units Image difference information of pixels; S23: Based on a pre-calibrated optical energy transfer lookup table, image difference information is mapped into a second control signal that drives the variable microstructure photoconductor; The expression for the second control signal is: ; In the formula, In micro-units The second control signal for the pixel; Represents a linear or nonlinear mapping function; S3: Input the first control signal to the light source module to generate a low-resolution substrate light field; S31: The first control signal is input to the light source module, and the Mini-LED chip array of the light source module emits a light beam in response to the first control signal; S32: The emitted beam forms a uniformly distributed low-resolution substrate light field through the optical homogenizing layer; S4: Input the second control signal into the variable microstructure optical guide to perform phase profile modulation on the low-resolution substrate optical field to form a high-resolution intermediate optical field; S41: The second control signal is input to the variable microstructure photoguide based on liquid crystal polymer. Based on the low-resolution substrate light field, the orientation distribution of liquid crystal molecules is controlled by voltage to form an effective refractive index spatial distribution. Combined with the fixed liquid crystal polymer layer thickness, a phase delay distribution is generated to achieve phase profile modulation and form a high-resolution intermediate light field. S411: The second control signal is input to the patterned ITO transparent electrode based on the variable microstructure photoguide realized by liquid crystal polymer, generating a spatially varying electric field distribution; the second control signal This includes a control voltage that generates a spatially varying, non-uniform electric field distribution between the patterned ITO transparent electrode and the ITO common electrode. S412: Based on a non-uniform electric field, the liquid crystal molecules in the liquid crystal polymer undergo reorientation related to the intensity of the non-uniform electric field, and each liquid crystal molecule changes according to the control voltage. S413: Based on the birefringence properties of liquid crystal molecules, the spatial orientation distribution of liquid crystal molecules causes a spatial change in the effective refractive index, forming an effective refractive index distribution. S414: Combining a fixed liquid crystal polymer layer thickness, the effective refractive index distribution generates a phase delay distribution for the low-resolution substrate light field, thereby forming the desired dynamic phase profile. The expression for the phase delay distribution is: ; In the formula, In micro-units Phase delay distribution of pixels; Indicates the wavelength of the incident light; Represents the spatial distribution of birefringence; Indicates the thickness of the liquid crystal polymer layer; In this embodiment, birefringence Greater than 0.1.

[0047] In this embodiment, different wavelengths will result in the same phase profile. Different phase delays are generated for the three colors RGB, i.e., when hour, .

[0048] S415: Based on dynamic phase profile, a plane wavefront is modulated into a complex wavefront, and the propagation of the complex wavefront is used to realize the redistribution and utilization of light energy to form a high-resolution intermediate light field. S42: Input the second control signal to the variable microstructure optical guide based on MEMS micromirror array. Based on the low-resolution substrate optical field, control the tilt angle or deformation of the micromirror surface through electrostatic drive to generate equivalent phase modulation and achieve phase profile modulation, forming a high-resolution intermediate optical field. S421: Input the second control signal to the driving electrode of the variable microstructure photoguide based on a MEMS micromirror array; the second control signal This includes the control voltage, which generates a spatially varying electrostatic attraction between the driving electrode and the micromirror array; S422: Using electrostatic attraction to drive each micromirror in the micromirror array, causing it to tilt or deform around the supporting structure, and changing its reflected light path according to the tilt or deformation of each micromirror, thus generating an optical path difference on the micromirror array. The expression for calculating the optical path difference is as follows: ; In the formula, In micro-units Optical path difference of pixels; This represents the equivalent displacement of the tilt angle or deformation of the micromirror. S423: Based on the optical path difference, the low-resolution substrate optical field is generated with equivalent phase modulation to form the desired dynamic phase profile; The expression for the equivalent phase modulation is: ; In the formula, In micro-units Equivalent phase modulation of pixels; Indicates the wavelength of the incident light; Represents the spatial distribution of birefringence; S424: Based on dynamic phase profile, a plane wavefront is modulated into a complex wavefront, and the propagation of the complex wavefront is used to realize the redistribution and utilization of light energy to form a high-resolution intermediate light field. S5: Utilizes a projection lens to project a high-resolution intermediate light field onto the screen, forming a high-resolution image.

[0049] In this embodiment, when the resolution of the input high-resolution image signal is 1920×1080, the resolution of the low-resolution substrate light field of the light source module is 960×540, the resolution of the variable microstructure light guide is 1920×1080, and the resolution of the generated high-resolution image is 1920×1080.

[0050] Example 3 Based on the same technical concept, this embodiment provides a projection method based on a Mini LED array and a variable microstructure light guide.

[0051] T1: Acquire high-resolution image signals; In this embodiment, the resolution of the high-resolution image signal is 2×2 pixels. Table 1 shows the data of each micro-unit of the original high-resolution image and the target output color.

[0052] Table 1. Raw high-resolution image data and target output color

[0053] T2: Decompose the high-resolution image signal into a first control signal and a second control signal; T21: Based on the high-resolution image signal, it is downsampled to generate a low-resolution base image, which is then used as the first control signal for the control light source module. In this embodiment, the number of pixels in the pooling window The resolutions of each component in the generated low-resolution base image are as follows: The resolution of the R component is: ; The resolution of the G component is: ; The resolution of component B is: .

[0054] T22: Upsample the low-resolution base image and compare the upsampled low-resolution base image with the high-resolution image to calculate the image difference information; In this embodiment, the upsampling process employs the nearest neighbor copy upsampling algorithm, with a scaling factor... Table 2 shows the resolution data of the intermediate images after upsampling, and Table 3 shows the image information difference data.

[0055] Table 2 Resolution data of intermediate images after upsampling

[0056] Table 3 Image Information Difference Data

[0057] T23: Based on a pre-calibrated optical energy transfer lookup table, image difference information is mapped into a second control signal that drives the variable microstructure photoconductor; T3: Input the first control signal to the light source module to generate a low-resolution substrate light field; In this embodiment, the resolution of the light source module is 1×1 pixels. The generated low-resolution substrate light field is displayed as bluish-gray (53,91,91).

[0058] T4: Input the second control signal into the variable microstructure optical guide to perform phase profile modulation on the low-resolution substrate optical field to form a high-resolution intermediate optical field; In this embodiment, the resolution of the variable microstructure light guide is 2×2 pixels.

[0059] Given that the target output color of microcell (1,1) is dark cyan (18,56,68), the phase profile modulation design for this microcell is as follows: For the 620nm red light (R) component: a strong gradient phase profile was designed to achieve a diffraction efficiency of 66% to deflect the red light output and retain it at a ratio of 34%. For the 550nm green light (G) component: the gradient phase profile in the design achieves a diffraction efficiency of 38% to deflect the green light output and retain it at a ratio of 62%; For the 450nm blue light (B) component: a weak gradient phase profile was designed to achieve a 25% diffraction efficiency to deflect the blue light output and retain it at a ratio of 75%. By changing the phase distribution of light to alter its wavefront shape, the incident plane wavefront is adjusted into the desired complex wavefront shape, thereby achieving the control of the light energy ratio of the three colors. As a result, the micro-unit forms a high-resolution intermediate light field that appears as deep cyan (18, 56, 68).

[0060] Based on the micro-units (1,2) and their target output color of yellow-green (66,128,32), the phase profile modulation is designed as follows: For the 620nm red light (R) component: a weak gradient phase profile is designed to deflect the red light slightly and collect additional red light. For the 550nm green light (G) component: a weak gradient phase profile is designed to deflect the green light slightly and collect additional green light. For the 450nm blue light (B) component: a strong gradient phase profile was designed to achieve a 65% diffraction efficiency to deflect the blue light output and retain it at a ratio of 35%. Similarly, the micro-unit forms a high-resolution intermediate light field that appears as yellow-green (66, 128, 32).

[0061] Based on the micro-unit (2,1) and its target output color of dark blue (0,23,251), the phase profile modulation is designed as follows: For the 620nm red light (R) component: design an extremely strong gradient phase profile to achieve almost 100% diffraction efficiency to deflect the red light for output; For the 550nm green light (G) component: a strong gradient phase profile was designed to achieve a 75% diffraction efficiency to deflect the green light output and retain it at a ratio of 25%. For the 450nm blue light (B component): design a focusing phase profile to collect blue light from the entire system; Similarly, the micro-unit forms a high-resolution intermediate light field that appears as deep blue (0,23,251).

[0062] Based on the micro-unit (2,2) and its target output color of orange-yellow (128,155,12), the phase profile modulation is designed as follows: For the 620nm red light (R) component: design a focusing phase profile to collect the red light from the entire system; For the 550nm green light (G) component: a weak gradient phase profile is designed to deflect the green light slightly and collect additional green light. For the blue (B) component at 450nm: an extremely strong gradient phase profile was designed to achieve 87% diffraction efficiency to deflect the green light output and retain it at a ratio of 13%. Similarly, the micro-unit forms a high-resolution intermediate light field that appears orange-yellow (128, 155, 12).

[0063] In this embodiment, the collaborative design of the phase profiles of all micro-units enables the redistribution and utilization of deflected non-target color light at the screen imaging level. Specifically, the red and green light deflected by micro-unit (1,1) flows to other micro-units, the blue light deflected by micro-unit (1,2) flows to other micro-units that need blue light, the red and green light deflected by micro-unit (2,1) flows to other micro-units, and micro-unit (2,2) receives the deflected light from other micro-units, thereby ensuring the conservation of system-level light energy.

[0064] In this embodiment, the generated high-resolution intermediate light field has a resolution four times that of the low-resolution substrate light field. To ensure the accuracy of the scheme, a light energy conservation verification was performed.

[0065] In the high-resolution intermediate light field, the total light energy of the R component is: The total light energy of component G is: The total light energy of component B is: .

[0066] In the low-resolution substrate light field, the total light energy of the R component is: The total light energy of component G is: The total light energy of component B is: ; After verification and comparison, the total light energy in the system is basically consistent, which means that the scheme meets the light energy conservation verification.

[0067] in, Figure 6 The diagram shown is a modulation schematic of each microunit.

[0068] T5: Uses a projection lens to project a high-resolution intermediate light field onto the screen to form a high-resolution image.

[0069] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0070] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A projection system based on a Mini LED array and a variable microstructure light guide, characterized in that, It includes a light source module, a variable microstructure light guide, a projection lens, and a drive control subsystem; The drive control subsystem, which is connected to the light source module and the variable microstructure photoconductivity, is configured to receive high-resolution image signals and decompose them into a first control signal and a second control signal, and synchronously drive the light source module and the variable microstructure photoconductivity. The high-resolution image signal is decomposed into a first control signal and a second control signal, including: Based on the high-resolution image signal, it is downsampled to generate a low-resolution base image, which is then used as the first control signal for the control light source module. The low-resolution base image is upsampled, and the upsampled low-resolution base image is compared with the high-resolution image to calculate the image difference information. Based on a pre-calibrated optical energy transfer lookup table, image difference information is mapped into a second control signal that drives the variable microstructure photoguide. The light source module is configured to generate a low-resolution substrate light field in response to a first control signal; The variable microstructure light guide is disposed in the light output path of the light source module; the variable microstructure light guide includes multiple micro-units, each of which is configured to respond to a second control signal and perform phase profile modulation on the low-resolution substrate light field to form a high-resolution intermediate light field. The projection lens is disposed on the light output path of the variable microstructure light guide and is used to amplify the high-resolution intermediate light field and project it onto the screen.

2. The projection system based on a Mini LED array and a variable microstructure light guide according to claim 1, characterized in that, The light source module includes a Mini-LED chip array, whose physical resolution is lower than the target output resolution of the high-resolution image signal, and is used to provide basic color and overall brightness.

3. A projection system based on a Mini LED array and a variable microstructure light guide according to claim 2, characterized in that, The light source module also includes: A heat dissipation substrate, which is coupled to the Mini-LED chip array; A first driving circuit is electrically connected to the Mini-LED chip array; An optical homogenizing layer is disposed in the light output path of the Mini-LED chip array to ensure the uniformity of the light field.

4. A projection system based on a Mini LED array and a variable microstructure light guide according to claim 1, characterized in that, When the variable microstructure photoguide is a phase modulator based on liquid crystal polymer, it includes, from top to bottom, an upper transparent substrate, an upper alignment layer, a liquid crystal polymer layer, a lower alignment layer, and a lower transparent substrate. Both the upper transparent substrate and the lower transparent substrate are made of glass or optical-grade polymer material; a patterned ITO transparent electrode is integrated on the inner surface of the upper transparent substrate; and an ITO common electrode is integrated on the inner surface of the lower transparent substrate. Both the upper alignment layer and the lower alignment layer are made of polyimide material; a pretilt angle is formed between the upper alignment layer and the upper transparent substrate, and between the lower alignment layer and the lower transparent substrate, to determine the initial orientation of the liquid crystal molecules; The liquid crystal polymer layer includes ferroelectric liquid crystal or nematic liquid crystal.

5. A projection system based on a Mini LED array and a variable microstructure light guide according to claim 1, characterized in that, When the variable microstructure photoguide is a phase modulator based on a MEMS micromirror array, it includes, from top to bottom, a micromirror array, a support structure, a driving electrode, and a silicon substrate. The silicon substrate on which the second driving circuit is integrated; The driving electrode is disposed on the silicon substrate; The support structure is mounted onto the silicon substrate; the support structure includes a torsion beam structure or a flexible support structure. The micromirror array is suspended above the driving electrode by the support structure; The micromirror array is configured to rotate or move vertically under the electrostatic attraction generated by the driving electrode.

6. A projection system based on a Mini LED array and a variable microstructure light guide according to claim 1, characterized in that, The projection lens includes multiple optical lenses; the projection lens is configured as either fixed-focus or zoom.

7. A projection system based on a Mini LED array and a variable microstructure light guide according to claim 1, characterized in that, The drive control subsystem includes: A signal receiving module is used to receive input high-resolution image signals; the input high-resolution image signal formats include HDMI, DisplayPort, and LVDS. The image processing module, which has a built-in FPGA chip or ASIC chip, is used to run a signal decomposition algorithm to decompose the input signal into a first control signal and a second control signal. The storage module is used to store a pre-calibrated optical energy transfer lookup table; A synchronization control module is used to ensure the synchronized driving of the light source module and the variable microstructure light guide; The power management module is used to provide control voltage.

8. A method for using the projection system based on a Mini LED array and variable microstructure light guide as described in claim 1, characterized in that, include: Acquire high-resolution image signals; The high-resolution image signal is decomposed into a first control signal and a second control signal, including: Based on the high-resolution image signal, it is downsampled to generate a low-resolution base image, which is then used as the first control signal for the control light source module. The low-resolution base image is upsampled, and the upsampled low-resolution base image is compared with the high-resolution image to calculate the image difference information. Based on a pre-calibrated optical energy transfer lookup table, image difference information is mapped into a second control signal that drives the variable microstructure photoguide. The first control signal is input to the light source module to generate a low-resolution substrate light field; The second control signal is input to the variable microstructure optical guide to perform phase profile modulation on the low-resolution substrate optical field and form a high-resolution intermediate optical field. A high-resolution intermediate light field is projected onto a screen using a projection lens to form a high-resolution image.

9. A method for a projection system based on a Mini LED array and a variable microstructure light guide according to claim 8, characterized in that, The step of inputting the second control signal to the variable microstructure optical guide to perform phase profile modulation on the low-resolution substrate optical field to form a high-resolution intermediate optical field includes: The second control signal is input to the variable microstructure photoguide based on liquid crystal polymer. Based on the low-resolution substrate light field, the orientation distribution of liquid crystal molecules is controlled by voltage to form an effective refractive index spatial distribution. Combined with the fixed liquid crystal polymer layer thickness to generate a phase delay distribution, phase profile modulation is achieved to form a high-resolution intermediate light field. Alternatively, a second control signal can be input to a variable microstructure photoguide based on a MEMS micromirror array. Based on the low-resolution substrate optical field, the tilt angle or deformation of the micromirror surface can be controlled by electrostatic drive to generate equivalent phase modulation and achieve phase profile modulation, thereby forming a high-resolution intermediate optical field.

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