Optical modulation device, optical waveguide apparatus, display system, and configuration method

Abstract

The invention provides an optical modulation device, an optical waveguide device, a display system and a configuration method. The optical modulation device comprises a gradient refractive index functional layer, and the gradient refractive index functional layer is configured to change the local refractive index based on a space temperature field applied to the gradient refractive index functional layer so as to perform phase modulation on transmitted light; wherein the space temperature field is generated by a heat source, and the heat source is generated by a heat addressing driving layer integrated on one side of the gradient refractive index functional layer or is generated by projection of an external source heat write-in device independent of the optical modulation device.

Description

Technical Field

[0001] This disclosure relates to the field of near-eye display technology, and more particularly to an optical modulation device, an optical waveguide device, a display system, and a configuration method. Background Technology

[0002] With the rapid development of near-eye display technology, augmented reality smart glasses are gradually becoming more common in the everyday consumer market. To achieve an immersive visual experience while maintaining the device's aesthetics, the optical system of augmented reality devices needs to possess extremely high light transmittance and an extremely thin physical form. However, there are significant differences in vision among different users, including myopia, hyperopia, astigmatism, and more complex higher-order wavefront aberrations.

[0003] Existing augmented reality devices typically address vision correction by using externally attached or magnetically attached traditional refractive lenses. This approach not only increases the overall thickness and weight of the system, undermining the industrial design goal of making smart glasses thin and light, but may also lead to structural interference or visual discomfort for the wearer due to the increased optical path. Another existing solution is to directly custom-mold the refractive power on the waveguide substrate; however, since the combinations of human visual parameters are virtually infinite, this would result in an exponential explosion in the number of stock units, making large-scale automated standard production extremely difficult and costly. Summary of the Invention

[0004] This disclosure provides an optical modulation device, an optical waveguide device, a display system, and a configuration method; it can solve the technical problems in existing augmented reality glasses vision correction solutions, such as the external refractive lens causing the device to be heavy, the increased optical path causing structural interference or wearing discomfort, the large number of customized waveguide mirrors making it impossible to mass-produce, and the difficulty of achieving high-precision phase modulation of light on a flat and thin substrate to complete vision correction in traditional correction methods.

[0005] The technical solution disclosed herein is implemented as follows: In a first aspect, this disclosure provides an optical modulation device, comprising: A gradient refractive index functional layer having a local refractive index distribution that matches vision correction parameters, the local refractive index distribution being induced by a spatial temperature field to modulate the phase of transmitted light; The spatial temperature field is generated by a heat source, which may be generated by a thermal addressing driving layer integrated on one side of the gradient refractive index functional layer, or by projection from an external thermal writing device independent of the optical modulation device.

[0006] Secondly, this disclosure provides an optical waveguide device, comprising: The optical modulation device as described in the first aspect; and A waveguide substrate, wherein the optical modulation device is attached to the surface of the waveguide substrate; The waveguide substrate has a first refractive index, and the light is transmitted within the waveguide substrate and coupled through the optical modulation device.

[0007] Thirdly, this disclosure provides an augmented reality display system, including: The optical waveguide device as described in the second aspect; An optical engine, optically coupled to the waveguide substrate, is configured to generate an image beam and project the image beam into the waveguide substrate for transmission. The controller is communicatively connected to the integrated hot-addressing driver layer or the external external hot-write device. The controller is configured to generate a drive signal based on vision correction data, and control the thermal addressing drive layer or the external thermal writing device to generate the corresponding spatial temperature field.

[0008] Fourthly, this disclosure provides a method for configuring a vision correction device, including: Provide the optical modulation device described in the first aspect; Obtain vision correction parameters; Based on the aforementioned vision correction parameters, calculate the required target refractive index distribution; The integrated thermal addressing driving layer, or the externally sourced thermal writing device, generates a spatial temperature field to drive the gradient refractive index functional layer to change its local refractive index until the target refractive index distribution is achieved; and A curing operation is performed to lock the local refractive index.

[0009] This disclosure provides an optical modulation device, an optical waveguide device, a display system, and a configuration method. By setting a gradient refractive index functional layer, the local refractive index is controlled by the spatial temperature field to achieve phase modulation of transmitted light, replacing the traditional method of relying on physical surface / thickness changes to achieve refraction. This achieves a planar design of the device, effectively reducing the device thickness and weight, avoiding problems such as increased optical path and structural interference caused by external lenses. At the same time, it can reshape the wavefront phase of light through precise changes in local refractive index, achieving optical modulation effects related to vision correction. The thermal addressing driving layer integrated on one side of the gradient refractive index functional layer can realize the integrated generation and control of the spatial temperature field, facilitating the integration and adaptation of the device with other optical components. The external thermal writing device, independent of the optical modulation device, can realize the passive design of the device, eliminating the need for built-in heating and driving circuits, improving the light transmittance of the device. Moreover, the two heat source solutions can be flexibly selected according to actual needs to adapt to different application scenarios. At the same time, the unified hardware infrastructure also provides support for the mass production of subsequent single-specification hardware. Attached Figure Description

[0010] Figure 1 This is an architecture diagram of an augmented reality display system provided in this disclosure.

[0011] Figure 2 This is a schematic diagram of an AR optical waveguide vision correction system provided in this disclosure.

[0012] Figure 3 This is a schematic diagram of an optical modulation device provided in this disclosure.

[0013] Figure 4 This is a schematic diagram of another optical modulation device provided in this disclosure.

[0014] Figure 5 This disclosure provides a schematic diagram of the principle of thermal field and refractive index mapping.

[0015] Figure 6 This is a schematic diagram of the structure of a hot-addressing drive layer provided in this disclosure.

[0016] Figure 7 A flowchart of a dynamic modulation mode provided in this disclosure.

[0017] Figure 8 This disclosure provides a flow chart of a hot-write and erase reconstruction process.

[0018] Figure 9 This disclosure provides a design principle diagram for astigmatism correction using a non-rotationally symmetric gradient refractive index distribution.

[0019] Figure 10 A flowchart illustrating a method for configuring a vision correction device provided in this disclosure. Detailed Implementation

[0020] The technical solutions in this disclosure will now be clearly and completely described with reference to the accompanying drawings.

[0021] This disclosure provides a novel optical modulation architecture. By introducing thermally responsive materials and precise thermal field control technology, this disclosure can construct complex optical surface effects on a flat physical surface by changing the microscopic local refractive index of the material, thereby eliminating the dependence on changes in the thickness of the physical lens.

[0022] See Figure 1 , Figure 1This is a schematic diagram of an augmented reality display system architecture provided in an embodiment of this disclosure. The embodiment of this disclosure provides an augmented reality display system including an optical waveguide device 11, a light engine 12, and a controller 13 that cooperates with the light engine and the optical waveguide device. The optical waveguide device 11 includes an optical modulation device 111 and a waveguide substrate 112. The optical modulation device 111 is bonded to the surface of the waveguide substrate 112.

[0023] In one embodiment of this disclosure, the refractive index of the waveguide substrate 112 is greater than or equal to 1.7, such as 1.8, and the total thickness of the optical waveguide device in the light transmission direction can be controlled to be less than or equal to 1.2 mm, for example, a high-refractive-index optical glass with a thickness of 1.1 mm can be selected. The high refractive index not only expands the critical angle range for total internal reflection of light inside the waveguide, thereby improving the field of view of the augmented reality display, but also effectively reduces dispersion and energy attenuation during light transmission.

[0024] In the augmented reality display system, the light engine 12 is optically coupled to the waveguide substrate 112 and configured to generate an image beam and project it into the waveguide substrate 112 for transmission. Specifically, the light engine 12 can be a micro-LED array or a silicon-based liquid crystal microdisplay. The initial beam carrying virtual image information emitted by the light engine enters the waveguide substrate 112 through an ingress coupling grating or prism structure. The light undergoes total internal reflection between the upper and lower surfaces of the waveguide substrate 112 until it reaches the egress coupling grating region. Subsequently, the light is coupled out of the waveguide substrate 112 and passes through the optical modulator 111 attached to the surface of the waveguide substrate 112, finally entering the user's eye. The controller 13, as the computing and command center of the entire system, not only controls the image output of the light engine 12 but also controls the changes in the optical state of the optical modulator 111.

[0025] Specifically, the aforementioned augmented reality display system can be applied to AR waveguide vision correction systems. See also... Figure 2 In the application process, the AR glasses can integrate an eye-tracking / distance sensor 204 on the side of the human eye 202, a main control chip 206 (MCU / FPGA), a microdisplay / optical engine 208, a TFT / heating drive circuit 210, a battery / power management module 212, and an external interface 214 (USB / wireless). The eye-tracking / distance sensor 204 is used to collect the user's vision-related data and visual scene data and transmit them to the main control chip 206. The main control chip 206 can be integrated with the above and the controller 13, or it can be set up separately, which will not be described in detail here.

[0026] The main control chip 206 generates a drive signal based on the collected data and the vision correction parameters received by the external interface 214. The signal is transmitted to the thermal addressing drive layer 1116 of the optical modulator 111 via the TFT / heating drive circuit 210. The battery / power management module 212 supplies power to the power modules of the entire system. The virtual image light generated by the microdisplay / optical engine 208 and the real light from the outside are both phase-modulated by the optical modulator 111 and then enter the human eye 202 to realize the corrected augmented reality visual presentation.

[0027] See in some examples Figure 3 The optical modulation device 111 provided in this embodiment includes a gradient refractive index functional layer 1111. The gradient refractive index functional layer 111 has a local refractive index distribution that matches vision correction parameters. The local refractive index distribution is induced by a spatial temperature field 30 to perform phase modulation on the transmitted light.

[0028] The gradient refractive index functional layer 1111 is configured to change the local refractive index based on the applied spatial temperature field 30 to phase modulate the transmitted light. Unlike the traditional principle of using the convexity or concavity of the lens's physical surface to change the optical path difference, the mark 30 only represents the area of ​​effect of the spatial temperature field or the direction of the thermal radiation vector, not the physical boundary.

[0029] This embodiment utilizes the physical mechanism that the optical path length equals the product of the refractive index and the physical thickness. Under the premise of maintaining absolute uniformity of the physical thickness, the wavefront phase of light transmitted through the gradient refractive index functional layer 1111 is reshaped by changing the continuous local refractive index inside the material.

[0030] The optical modulation device 111 disclosed herein achieves refractive index modulation based on the thermo-optical effect or thermal phase transition characteristics of the material. By controlling the temperature on the plane, the refractive index of the material at that location is changed. It constructs a refractive index distribution model containing quadratic terms and higher-order Zernike terms on a high-refractive-index flat waveguide with a refractive index greater than or equal to 1.7, thereby replacing the core design of a physical curved lens.

[0031] Among them, the gradient refractive index functional layer 1111 is a refractive correction layer, and different functional materials can be selected according to the working mode. The working mode can include dynamic modulation mode and static writing mode, which will be explained in detail later.

[0032] The gradient refractive index functional layer 1111 is for light phase modulation and vision correction. Based on the thermo-optic effect or thermal phase transition characteristics, it responds to the spatial temperature field 30 generated by the heat source, changes the local refractive index and forms a controllable refractive index distribution. This distribution covers spherical, cylindrical and Zernike higher-order terms, which can replace physical curved lenses to achieve myopia / hyperopia and astigmatism correction, and can also accurately compensate for higher-order aberrations such as coma and cloverleaf aberration; at the same time, it supports the erasure and rewriting of the refractive index distribution to realize the reconfigurability of device functions.

[0033] In some examples, refer to Figure 4 The optical modulation device 111 is arranged sequentially from the external side to the human eye 202 side as a first coating protective layer 1112, an encapsulation layer 1113, a high refractive adhesive layer 1114, a base glass layer 1115, a thermal addressing driving layer 1116, a gradient refractive index functional layer 1111 (GRIN layer), and a second coating protective layer 1117.

[0034] The first protective coating layer 1112 is a protective layer made of optical-grade coating material. It is the first layer structure that protects the device from damage to the internal layers of the device caused by external dust, moisture, scratches, etc., while reducing the reflection loss of external light on the surface of the device, improving the light transmittance, and ensuring the effective transmission of external real light and AR virtual light.

[0035] The high-refractive-index adhesive layer 1114 is a high-refractive-index optical adhesive layer 1114. For example, it has a thickness of 0.01 mm and a refractive index greater than or equal to 1.74. It is a special layer for refractive index matching, which is used for optical refractive index matching. It eliminates the refractive index difference between the first coating protective layer 1112 and the base glass layer 1115, avoids total internal reflection or Fresnel reflection of light at the interface between the two layers, reduces light loss, ensures efficient transmission of light in the waveguide system, and at the same time plays a role in interlayer bonding and fixing.

[0036] The substrate glass layer 1115 is a core support substrate made of high-refractive-index optical glass with a thickness of less than or equal to 1.2 mm and a refractive index of greater than or equal to 1.7. It serves as the physical support body and is flat. It provides a flat and robust bearing foundation for all functional layers, ensuring the overall flatness and thinness of the device. As the substrate of the optical modulation device 111, the substrate glass layer 1115 enables total internal reflection transmission of light within the layer, expands the critical angle range of total internal reflection, improves the field of view (FOV) of the AR image, and reduces the dispersion and energy attenuation of light transmission.

[0037] The thermal addressing driving layer 1116 is a micro-nano heating array layer made of transparent conductive thin film. It can be a micro-resistive heating array driven by transparent thin film transistors. The pixel pitch is greater than or equal to 20 and less than or equal to 50 μm. Some structures have micro-insulation grooves / aerogel filling structures between pixels.

[0038] The thermal addressing driving layer 1116 enables precise temperature field control. Based on vision correction data, it can drive micro-resistors through transparent thin-film transistors to generate a controllable spatial temperature field 30 (including a dynamically changing temperature field and a fixed write-type temperature field), and transmit the temperature field to the lower gradient refractive index functional layer 1111 to achieve local refractive index control of the gradient refractive index functional layer 1111. At the same time, the heat insulation structure between pixels can block the lateral diffusion of heat, ensure the pixel-level accuracy of the temperature field, and avoid thermal crosstalk.

[0039] The second protective coating 1117 is a protective layer made of optical-grade coating material. For example, its thickness is less than or equal to 3μm. The second protective coating 1117 is the last layer structure on the side of the device that contacts the human eye 202. It prevents the shedding of internal layers and impurities from the human eye 202 from contacting the human eye 202, while also preventing sweat and moisture from the human eye 202 from eroding the internal functional layers. It reduces the reflection of light at the interface on the side of the human eye 202, ensuring that the corrected light enters the human eye 202 efficiently and clearly, improving the visual experience, and also playing a slight anti-glare role.

[0040] To generate the desired refractive index distribution within the gradient refractive index functional layer 1111, extremely high-precision thermal energy needs to be applied to it. In this embodiment of the disclosure, the spatial temperature field 30 is generated by a heat source, which may include a thermally addressed driving layer 1116 integrated on one side of the gradient refractive index functional layer 1111, or by projection from an external thermal writing device independent of the optical modulation device 111.

[0041] When the heat source is the thermal addressing driving layer 1116 integrated on one side of the gradient refractive index functional layer 1111, the thermal addressing driving layer 1116 is typically a micro-resistive heating network driven by a transparent thin-film transistor.

[0042] When the heat source is an external thermal writing device independent of the optical modulation device 111, the optical modulation device 111 itself can be designed as a passive, purely optical consumable lens without any internal circuitry or heating electrodes. In this case, the external thermal writing device can be a high-precision infrared laser scanner placed in an optometry shop or on a factory assembly line. The controller 13 is communicatively connected to the external thermal writing device, controlling the focal position, scanning path, laser pulse width, and output power of the laser beam, thereby directly applying heat energy to the interior of the gradient refractive index functional layer 1111 in a non-uniform projection manner, generating a spatial temperature field 30. This purely passive implementation further reduces the manufacturing cost of a single augmented reality smart glasses and enables the lens itself to achieve extreme transparency indistinguishable from ordinary glass. Infrared laser scanning heating is also an important alternative to the heating method in this disclosure. Compared with resistance heating, this method does not require built-in electrodes, allowing the lens to have higher light transmittance.

[0043] To adapt to different application scenarios and power consumption requirements, the gradient refractive index functional layer 1111 of this disclosure is configured to have both dynamic modulation and static write modes. This disclosure constructs a dual-mode thermal addressing architecture that simultaneously supports online dynamic control and offline thermal writing / fixing via an integrated transparent micro / nano heating array.

[0044] In dynamic modulation mode, the thermally addressed driving layer 1116 maintains a time-varying spatial temperature field 30 to adjust the local refractive index in real time. In dynamic modulation mode, the substrate glass layer 1115 can be an ITO microresistive heating array driven by transparent TFTs (thin-film transistors) with a thickness of 1.1 mm and a refractive index of 1.8. Pixel pitch is greater than or equal to... and less than or equal to .

[0045] In the dynamic modulation mode, the thermo-optic effect of the material is relied upon, meaning that the refractive index of the material changes instantaneously and reversibly with the change of the current ambient temperature. In this mode, the gradient refractive index functional layer 1111 contains liquid crystal material or a thermosensitive polymer.

[0046] Taking a nematic liquid crystal with a large thermo-optic coefficient as an example, its refractive index is sensitive to the rate of temperature change. When each pixel in the thermally addressed driving layer 1116 outputs different Joule heats, a specific three-dimensional temperature gradient is formed within the liquid crystal layer, causing a local deflection of the director of the liquid crystal molecules, thereby instantaneously forming a phase delay distribution similar to a Fresnel lens. Since this change is real-time, the controller 13 can change the spatial temperature field 30 at a high refresh rate according to the distance of the user's gaze point captured by the eye tracker, thereby adjusting the focal length of the lens in real time, so that the focal plane of the virtual image always remains consistent with the gazed object in the real world, solving the convergence conflict problem that causes dizziness in users in traditional augmented reality devices.

[0047] Specifically, on the plane of the control gradient refractive index functional layer 1111 Temperature at the location Change the refractive index of the material at that location To achieve the focusing function of the lens, the target refractive index distribution... The following extended model (covering spherical, cylindrical, and higher-order terms) must be satisfied:

[0048] in Thermo-optic coefficient, To control the degree of myopia / hyperopia, To control astigmatism, These are higher-order aberration coefficients. The reference refractive index is used for the material. for Zernike Polynomial basis functions. This disclosure establishes a non-rotationally symmetric basis function through pixelated thermal control. T(x,y) Temperature field, mapping Zernike The polynomial coefficients overcome the limitation of traditional lenses that can only correct spherical and cylindrical lenses, enabling vision correction. When converting this model into a target temperature matrix of a pixel array, the target temperature matrix needs to be pre-corrected using a deconvolution algorithm to compensate for inter-pixel crosstalk caused by thermal diffusion.

[0049] See Figure 5 This thermal field and refractive index mapping diagram exemplifies the field distribution mapping relationship of a thermo-optical material where temperature and refractive index are negatively correlated. The diagram comprises two parts: one is a physical optical path cross-section of the optical waveguide / gradient refractive index functional layer 1111, and the other is... z The axis is the optical axis / direction of light propagation. y Or r is the radial coordinate, and the gradient refractive index functional layer 1111 is along z The first aspect involves the transmission and phase modulation of light along the optical axis; the second aspect is the distribution curve of the thermal field and refractive index, with radial coordinates. y or r Corresponding spatial temperature field distribution 30 T(y) Local refractive index distribution of gradient refractive index functional layer 1111 n (y) They exhibit a one-to-one mapping relationship, and the local refractive index distribution... n(y) Satisfying the aforementioned gradient refractive index extension model intuitively demonstrates that the distribution characteristics of the space temperature field 30 directly determine the local refractive index distribution state of the gradient refractive index functional layer 1111, and is a visual physical representation of the space temperature field 30 regulating the local refractive index.

[0050] Local refractive index distribution n(y) The specific mapping relationship with temperature is as follows:

[0051] in, For maximum refractive index, Let be the coefficient of refractive index as a function of temperature. When the local refractive index is positively correlated with temperature, When the local refractive index is negatively correlated with temperature, a positive value is taken. Take the negative value.

[0052] See in some examples Figure 6The thermally addressed driving layer 1116 includes a heating unit array. When the spatial temperature field 30 is generated by the integrated thermally addressed driving layer 1116, in order to achieve high-resolution aberration correction, the thermally addressed driving layer 1116 includes a heating unit array. Each heating unit is composed of a micro heating resistor 501, a TFT driving unit 502, a thermal isolation structure 503, and a substrate surface 504 in sequence. The micro heating resistor 501 is the core heating element of the pixel unit, used to generate heat energy to regulate the local refractive index of the gradient refractive index functional layer 1111. The TFT driving unit 502 is electrically connected to the micro heating resistor 501 to achieve independent and precise control of the heating temperature of a single pixel unit. The thermal isolation structure 503 is a gap structure set outside the micro heating resistor 501. The substrate surface 504 provides stable physical support for the entire pixel unit. This pixel-level structural design realizes the fine control of the spatial temperature field 30 by the thermally addressed driving layer 1116, laying the foundation for the formation of a precise local refractive index distribution in the gradient refractive index functional layer 1111. The thermal isolation structure 503 can block the lateral diffusion of heat within the gradient refractive index functional layer 1111. The driving parameters of the TFT driving unit 502 can be pre-corrected using a deconvolution algorithm to counteract thermal diffusion crosstalk between pixels.

[0053] Specifically, the thermal insulation structure 503 includes at least one of an air gap, a vacuum groove, or an aerogel filling layer. Different structural types all have low thermal conductivity characteristics. The specific structural type can be customized based on user needs, which will not be elaborated here.

[0054] See Figure 7 In dynamic modulation mode, step S710 can be executed first to obtain the target phase map based on the vision data collected by the sensor or input by the user, and then step S720 can be executed to calculate the thermal field mapping and convert the Zernike coefficients into a target temperature matrix of pixel array.

[0055] Next, in step S730, the TFT array is driven, and the main control chip 206 applies voltage to the micro heating resistor 501. Then, in step S740, it is determined whether the current temperature matrix is ​​equal to the target temperature matrix. If not, step S730 is continued after PID adjustment. Subsequently, the TFT driving unit 502 drives the corresponding micro heating resistor 501 to heat according to the target temperature, forming a Fresnel-like lens or freeform surface spatial temperature field 30 on the surface of the gradient refractive index functional layer 1111. If so, step S750 is executed to form a dynamic gradient refractive index lens that matches the temperature field. Then, step S760 is executed to determine whether the user or scene has changed. If so, step S710 is returned. If not, step S770 is executed to maintain the current state.

[0056] In some examples, dynamic modulation modes require continuous power consumption to maintain the temperature field, which is uneconomical for mobile devices with limited battery capacity in daily use where only fixed vision correction is needed. Therefore, embodiments of this disclosure introduce a more fundamental static write mode. In static write mode, the spatial temperature field 30 generated by the thermal addressing drive layer 1116 or an external thermal writing device heats the gradient refractive index functional layer 1111 above its transition temperature and solidifies the local refractive index distribution after cooling.

[0057] To achieve state solidification, in static write mode, the gradient refractive index functional layer 1111 contains chalcogenide glass material or phase change polymer. Taking germanium-antimony-tellurium alloy material or chalcogenide glass derivatives doped with specific elements as examples, the microstructure of such phase change materials will transform between an amorphous amorphous state and a regularly arranged crystalline state under different thermal histories, accompanied by a huge difference in macroscopic refractive index. The controller 13 controls the heat source to emit short and intense thermal pulses to locally heat the phase change material in the target area to a temperature higher than its glass transition temperature, for example, between 100 and 150 degrees Celsius, but below its melting point. If thermal addressing driving layer heating is used, the controller optimizes the heating pulse parameters of each pixel through a deconvolution algorithm to ensure the accuracy of the thermal field and avoid refractive index distribution deviation caused by thermal diffusion; if external laser heating is used, the deconvolution algorithm will optimize the laser pulse width and power density to compensate for the diffusion of the laser thermal field.

[0058] Within this temperature range, the material is in a highly elastic or softened state, with enhanced molecular chain segment mobility. Subsequently, the heat source is rapidly removed or its power reduced, causing the material to undergo an extremely short quenching cooling process, such as crystallization time on the order of 20 nanoseconds. This ultrafast cooling process freezes the internal structure of the material at a predetermined ratio before it can recover its original state, thus permanently transcribing the non-uniform spatial temperature field 30 into a fixed local refractive index distribution. Once cooling and solidification are complete, even after removing all external power supply or laser irradiation, the gradient refractive index functional layer 1111 can still maintain the optical phase modulation capability required for vision correction for a long time, achieving true zero-power operation.

[0059] See Figure 8 This hot-write and erase-reconstruction process flow diagram fully demonstrates the entire process state changes of the gradient refractive index functional layer 1111 in static write mode, from refractive index writing to solidification and locking, and subsequent erase-reconstruction. The state changes of the gradient refractive index functional layer 1111 are divided into three core stages and can be cyclically reconstructed through a thermal field: A is the initial state / erasing state, at which time the gradient refractive index functional layer 1111 is in a molecularly disordered state with a uniform initial refractive index. n0 represents a blank state where no refractive index distribution has been written; B represents a softened / excited state, where the gradient refractive index functional layer 1111 is heated to the transition temperature (glass transition temperature T) by the spatial temperature field 30 generated by the thermal addressing driving layer 1116 or an external thermal writing device. g Above this, the gradient refractive index functional layer 1111 undergoes a phase transition / softening, and the field-induced effect reconstructs the local molecular arrangement towards the target refractive index distribution. C is the working / locked state. Through rapid cooling or UV curing, the molecular arrangement state of state B is locked, and the gradient refractive index functional layer 1111 forms a stable target gradient refractive index distribution. n(x,y) After completing the writing of vision correction parameters, it enters a working state that can be used without power.

[0060] In this embodiment of the disclosure, the optical modulation device 111 is rewritable in static write mode. The gradient refractive index functional layer 1111 is configured to return to its initial refractive index state after being heated to the erase temperature. Figure 4 As shown, when the refractive index distribution of the gradient refractive index functional layer 1111 needs to be erased and rewritten, a high-energy thermal field is applied to the entire gradient refractive index functional layer 1111 through the thermal addressing drive layer 1116 or an external thermal writing device, heating it to the erasure temperature. This causes the molecular structure of the gradient refractive index functional layer 1111 to be completely reset, breaking through the original solidified molecular arrangement state. After rapid cooling, the gradient refractive index functional layer 1111 recovers from the C working state / locked state to the A initial state / erasure state, returning to the blank state of uniform initial refractive index n0. The writing-curing process can then be performed again to complete the writing of new vision correction parameters.

[0061] When a user's vision prescription changes, such as an increase in myopia, there is no need to discard the existing augmented reality glasses. A high-energy thermal field is applied to the entire gradient refractive index functional layer 1111 through an external thermal writing device or the internal thermal addressing driving layer 1116, heating the entire layer to an extremely high erase temperature, such as the melting temperature of a phase change material, typically around 600 degrees Celsius.

[0062] Upon reaching a molten state, the original crystal structure within the material is completely destroyed. A rapid cooling process then restores the material to its initial amorphous state with an absolutely uniform refractive index. Based on this, the system can receive new vision correction data again, repeat the local heating and cooling curing steps, and write the new prescription into the lens. This rewritable feature perfectly supports computer-aided design companies' business strategies of providing manufacturers with single-specification hardware. By simply flashing different temperature field parameters into the software at the factory or retail point, the same standard lens can be customized into thousands of different vision prescriptions, greatly reducing supply chain complexity.

[0063] In this embodiment, the change in local refractive index corresponds to a combination of Zernike polynomials used to correct wavefront aberrations. Zernike polynomials are a set of continuously orthogonal polynomial basis functions on the unit circle, widely used in ophthalmic optics and adaptive optics to accurately describe wavefront distortion. The internal computation module of controller 13 decomposes the three-dimensional wavefront aberration data received from external ophthalmic optometry equipment into a series of Zernike polynomial coefficients.

[0064] Figure 9 The refractive index distribution of the gradient refractive index functional layer 1111 in the horizontal direction (X-axis) is presented. n(x) Refractive index distribution in the vertical direction (Y-axis) n(y) A non-rotationally symmetric spatial temperature field 30 is constructed through the thermally addressed driving layer 1116, enabling the gradient refractive index functional layer 1111 to form an anisotropic refractive index distribution that matches the astigmatism correction requirements. n(x,y) This distribution aligns with the astigmatism coefficient control logic in the aforementioned gradient refractive index extension model, and is a concrete application of Zernike polynomial combination in astigmatic wavefront aberration correction.

[0065] Specifically, the target refractive index distribution is set as the sum of the base refractive index and the thermo-optical refractive index variable caused by the spatial temperature field 30. This thermo-optical refractive index variable is expanded in the mathematical model into a formula containing several specific aberration terms. n(x,y)=n 0 +…+Zernike The high-order fitting achieves a correction accuracy far exceeding that of traditional discrete lenses.

[0066] The Zernike polynomial includes at least terms for correcting defocus, terms for correcting astigmatism, and higher-order aberration terms for correcting coma or cloverleaf aberration. In the calculation logic of controller 13, the refractive index at the target location is approximately equal to the material's reference refractive index, plus the product of the defocus coefficient controlling myopia or hyperopia and the sum of the squares of the horizontal and vertical coordinates, plus the product of the astigmatism coefficient controlling the astigmatism axis and degree and the difference in the squares of the horizontal and vertical coordinates, plus the sum of the products of each higher-order Zernike coefficient and its corresponding polynomial basis function. Through this mathematical-physical mapping relationship, controller 13 can calculate the precise local refractive index required for each tiny region in the array, and then deduce the specific heat value or output voltage amplitude that the heat source needs to apply to that coordinate position to achieve that refractive index. This control strategy based on Zernike polynomial combinations enables the optical modulation device 111 to exhibit optical correction accuracy far exceeding that of traditional freeform lenses in a completely flat form, achieving super-correction of visual defects in the human eye 202.

[0067] This disclosure provides a method for configuring a vision correction device, referring to... Figure 10The process includes the following steps S1010 to S1040.

[0068] In step S1010, an optical modulation device is provided.

[0069] As mentioned earlier, the optical modulation device provided here can be a standardized blank substrate element without any specific vision prescription, whose gradient refractive index functional layer is in a uniform initial refractive index state. Structurally, the device includes, from the human eye side to the external side, a second protective coating layer, a gradient refractive index functional layer, a thermally addressed drive layer, a high refractive index waveguide substrate, a high refractive index matching adhesive layer, and a first protective coating layer. To ensure that the light input to the optical engine does not experience severe total internal reflection loss or Fresnel reflection during total internal reflection transmission within the waveguide, the high refractive index matching adhesive layer located above the waveguide substrate is designed to have a refractive index greater than or equal to 1.74, and its thickness is controlled to be around 0.01 mm, thereby forming a perfect optical impedance match with the waveguide substrate with a refractive index greater than or equal to 1.7.

[0070] Next, step S1020 is executed to obtain vision correction parameters.

[0071] The system can obtain a complete set of vision correction parameters for the current target user from professional wavefront aberrometers, autorefractors, or medical cloud databases through wired or wireless data interfaces. These parameters include not only traditional spherical and cylindrical power, but also high-order aberration data describing irregular defects in the individual cornea and lens.

[0072] Subsequently, step S1030 is executed, calculating the required target refractive index distribution based on the vision correction parameters. The processor executes the aforementioned mapping algorithm based on Zernike polynomials, transforming the clinical refractive power and aberration micrometer values ​​into a digital model matrix of refractive index gradients on a two-dimensional plane.

[0073] Next, step S1040 is executed, controlling the integrated thermal addressing driving layer or controlling the external external thermal writing device to generate a spatial temperature field to drive the gradient refractive index functional layer to change its local refractive index until the target refractive index distribution is achieved.

[0074] In some examples of this disclosure, if an integrated heat source is used, controller 13 converts the digital matrix into a pulse-width modulation signal, driving a transparent thin-film transistor to inject precise current into the indium tin oxide microresistor array. If a separate external thermal writing device is used, controller 13 directs a high-precision infrared laser scanning system to scan the surface of the optical modulation device point-by-point using a laser beam of specific wavelength and power density, based on a calculated spatial temperature field distribution map. The laser energy is absorbed by the phase change polymer or chalcogenide glass material in the gradient refractive index functional layer, causing its local temperature to rise above the softening point or glass transition temperature. In this softened state, the molecular chain segments or lattice structure inside the material rearrange under thermodynamic action, thus macroscopically manifesting as a precise change in local refractive index.

[0075] Finally, step S1050 is performed to perform a curing operation to lock the local refractive index.

[0076] The physical mechanism of the curing operation depends on the specific material system used in the gradient refractive index functional layer. For thermo-induced phase change materials, the curing operation typically manifests as a precisely controlled thermal quenching process. After reaching the target state, the heat source is instantly cut off, causing the material's temperature to plummet to room temperature within an extremely short time of tens of nanoseconds. Due to the extremely rapid cooling rate, the material molecules cannot return to their pre-heating state, thus permanently locking the proportion of crystalline or amorphous mixed states induced by the spatial temperature field, achieving the curing of the refractive index distribution. For photopolymer materials with thermal memory effects, the curing operation involves exposing the entire device to full-screen floodlight using a specific wavelength of ultraviolet light while the material is in a high-temperature plastic-shaping state. After the curing operation is completed, the optical modulation device becomes a custom-made vision correction lens, continuously performing phase modulation without any external power during subsequent daily wear. Furthermore, as a further extended alternative to the embodiments of this disclosure, the gradient refractive index functional layer can also use a photo-induced refractive index change material instead of a thermosensitive material. In this case, the external writing device will write and lock the refractive index by projecting a spatial light field of a specific intensity rather than a temperature field. This alternative also falls within the core concept of realizing the software functionality of this disclosure.

[0077] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

[0078] Those skilled in the art will recognize that the functions described in this disclosure in one or more of the examples above can be implemented using hardware, software, firmware, or any combination thereof. When implemented in software, these functions can be stored in a computer-readable medium or transmitted as one or more instructions or code on a computer-readable medium. Computer-readable media include computer storage media and communication media, wherein communication media include any medium that facilitates the transfer of a computer program from one place to another. Storage media can be any available medium accessible to a general-purpose or special-purpose computer.

[0079] It should be noted that the technical solutions described in this disclosure can be combined arbitrarily as long as they do not conflict.

[0080] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An optical modulation device, characterized in that, include: A gradient refractive index functional layer has a local refractive index distribution that matches vision correction parameters. The local refractive index distribution is induced by a spatial temperature field to modulate the phase of transmitted light. The spatial temperature field is generated by a heat source, which may be generated by a thermal addressing driving layer integrated on one side of the gradient refractive index functional layer, or by projection from an external thermal writing device independent of the optical modulation device.

2. The optical modulation device according to claim 1, characterized in that, The gradient refractive index functional layer is configured to have a dynamic modulation mode and a static write mode; In the dynamic modulation mode, the thermal addressing driving layer maintains the time-varying spatial temperature field to adjust the local refractive index in real time; In the static write mode, the spatial temperature field generated by the thermal addressing driving layer or the external thermal writing device heats the gradient refractive index functional layer to above the transition temperature, and solidifies the local refractive index distribution state after cooling.

3. The optical modulation device according to claim 2, characterized in that, In the static write mode, the optical modulation device is rewritable; The gradient refractive index functional layer is configured to return to its initial refractive index state after being heated to the erasure temperature.

4. The optical modulation device according to claim 1, characterized in that, When the heat source is the integrated thermal addressing driving layer, the thermal addressing driving layer includes a heating unit array, and the optical modulation device further includes: A thermal isolation structure is disposed between adjacent heating units to block the lateral diffusion of heat within the gradient refractive index functional layer.

5. The optical modulation device according to claim 4, characterized in that, The thermal insulation structure includes at least one of an air gap, a vacuum groove, or an aerogel filling layer.

6. The optical modulation device according to claim 1, characterized in that, The change in local refractive index corresponds to a combination of Zernike polynomials used to correct wavefront aberrations of light rays.

7. The optical modulation device according to claim 1, characterized in that, The gradient refractive index functional layer comprises at least one of liquid crystal material, chalcogenide glass material, or phase change polymer.

8. An optical waveguide device, characterized in that, include: The optical modulation device as described in any one of claims 1 to 7; as well as A waveguide substrate, wherein the optical modulation device is attached to the surface of the waveguide substrate; In this process, light propagates within the waveguide substrate and couples through the optical modulation device.

9. An augmented reality display system, characterized in that, include: The optical waveguide device as described in claim 8; An optical engine, optically coupled to the waveguide substrate, is configured to generate an image beam and project the image beam into the waveguide substrate for transmission. The controller is communicatively connected to the integrated hot-addressing driver layer or the external external hot-write device. The controller is configured to generate a drive signal based on vision correction data, and control the thermal addressing drive layer or the external thermal writing device to generate the corresponding spatial temperature field.

10. A method for configuring a vision correction device, characterized in that, include: Provide an optical modulation device as described in any one of claims 1 to 7; Obtain vision correction parameters; Based on the aforementioned vision correction parameters, calculate the required target refractive index distribution; The integrated thermal addressing driving layer, or the externally sourced thermal writing device, generates a spatial temperature field to drive the gradient refractive index functional layer to change its local refractive index until the target refractive index distribution is achieved; and A curing operation is performed to lock the local refractive index.

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