Method for determining preparation parameters of holographic optical element

Abstract

The embodiment of the invention belongs to the technical field of holographic optical elements, and provides a preparation parameter determination method of a holographic optical element, and the method comprises the steps: obtaining a plurality of pieces of detection data of an optical holographic element in a target use scene, the detection data are detection data in a user eye box range obtained through simulation parameters in a target use scene, and Bragg grating periods of the holographic optical elements corresponding to any two simulation parameters in the plurality of simulation parameters are different; in the multiple pieces of detection data, multiple pieces of target detection data without rainbow patterns within the range of the eye box of the user are determined; and determining a plurality of preparation parameters of the holographic optical element according to the target simulation parameters corresponding to the plurality of target detection data. Therefore, the preparation parameters without the rainbow patterns in the target use scene can be determined, so that the holographic optical element obtained according to the preparation parameters does not have the rainbow patterns in the use process, and the user experience is improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of holographic optical elements, and more specifically, to a method for determining preparation parameters of a holographic optical element. Background Art

[0002] Holographic optical elements (HOE films) are optical components made according to the principles of holography. HOE films have a periodic microstructure that can be considered a Bragg grating structure. When a light beam is incident on the HOE film, the HOE film splits the beam into multiple beams and recombine them to form a diffraction pattern. This diffraction pattern is caused by phase differences in the light beams, which are caused by changes in the refractive index of the grating inside the HOE film as the light beam passes through it.

[0003] Since the HOE film can focus the light beam to a point or spread the light beam to an area to form a diffraction pattern, the HOE film can be used to manufacture holographic lenses. The HOE film can be used in a variety of scenarios that require holographic lenses. For example, the HOE film can be used in an augmented reality head-up display (ARHUD) system. In the ARHUD system, the HOE film is on the front windshield, so that the ARHUD system can integrate the information of the entire vehicle, use the front windshield as a projection medium to reflect the image, and project the vehicle information directly in front of the driver's field of view, so that the driver can see the vehicle information without lowering his head or turning his head as much as possible.

[0004] However, in the usage scenarios of the HOE film, there is a situation where ambient light shines on the HOE film. The Bragg grating structure inside the HOE film may cause rainbow patterns in the formed image under the illumination of the ambient light source, which may affect the safety of the driver. Summary of the Invention

[0005] An exemplary embodiment of the present application provides a method for determining preparation parameters of a holographic optical element, which can determine preparation parameters that do not have rainbow patterns in a target usage scenario, so that the holographic optical element obtained according to the preparation parameters does not have rainbow patterns during use, thereby improving user experience.

[0006] In a first aspect, the present application provides a method for determining preparation parameters of a holographic optical element, comprising:

[0007] Acquiring a plurality of detection data of the optical holographic element in a target usage scenario, wherein the detection data is detection data within a user's eye box obtained by simulating parameters in the target usage scenario, wherein any two of the plurality of simulation parameters correspond to different structural parameters of the Bragg grating of the holographic optical element;

[0008] Determining, among the plurality of detection data, a plurality of target detection data in which rainbow patterns do not exist within the user's eye box range;

[0009] A plurality of preparation parameters of the holographic optical element are determined according to the target simulation parameters corresponding to the plurality of target detection data.

[0010] In some embodiments of the present application, the detection data includes the intensities of light beams of multiple wavelengths at multiple angles;

[0011] The determining of multiple target detection data in which rainbow patterns do not exist within the user's eye box range among the multiple detection data includes:

[0012] For each of the detection data, determining the maximum intensity of the light beam of each wavelength in the detection data, and determining the center angle corresponding to the intensity maximum, to obtain multiple intensity maximum values ​​and multiple center angles;

[0013] Calculating the difference between the center angles of light beams of any two wavelengths to obtain a plurality of first differences;

[0014] Calculating the difference between the maximum intensities of the light beams of any two wavelengths to obtain a plurality of second difference values;

[0015] If the multiple first difference values ​​are all smaller than the first preset value, and / or there is a value greater than the second preset value among the multiple second difference values, it is determined that the detection data is target detection data in which no rainbow pattern exists within the user's eye box range, and multiple target detection data are obtained.

[0016] In some embodiments of the present application, the simulation parameters include the incident angle of visible light and the structural parameters of the Bragg grating of the holographic optical element. The determining of multiple preparation parameters of the holographic optical element based on the target simulation parameters corresponding to the target detection data includes:

[0017] Analyzing and processing the target incident angle of visible light corresponding to each target detection data and the structural parameters of the target Bragg grating of the holographic optical element in the plurality of target detection data, determining the object light phase corresponding to each target detection data, and obtaining a plurality of object light phases;

[0018] The phases of the plurality of object lights and the structural parameters of the plurality of target Bragg gratings are determined as a plurality of preparation parameters of the holographic optical element.

[0019] In some embodiments of the present application, the method further includes:

[0020] In a simulation scenario corresponding to the target usage scenario, visible light is incident on a plurality of holographic optical elements at a plurality of incident angles, and the light beams passing through the optical holographic elements are detected to obtain a plurality of detection data.

[0021] In some embodiments of the present application, the detection data includes the intensities of light beams of multiple wavelengths at multiple angles;

[0022] The light beam after passing through the optical holographic element is detected to obtain a plurality of detection data, including:

[0023] The light beam passing through the optical holographic element is subjected to far-field detection to obtain the corresponding intensities of light beams of multiple wavelengths at multiple angles in the far field.

[0024] In a second aspect, the present application provides a method for preparing a holographic optical element, the method comprising:

[0025] Determining a target usage scenario of the holographic optical element and obtaining scene parameters corresponding to the target usage scenario;

[0026] Determining, according to the scenario parameter, a target preparation parameter from a plurality of preparation parameters corresponding to the target usage scenario, the plurality of preparation parameters being obtained according to the method described in any one of the first aspects above;

[0027] The holographic optical element is produced using target production parameters.

[0028] In some embodiments of the present application, the scene parameter includes the phase of the target object light, and the preparation parameter includes the phases of multiple object lights and the structural parameters of the corresponding Bragg gratings;

[0029] Determining a target preparation parameter from a plurality of preparation parameters corresponding to the target usage scenario according to the scenario parameter includes:

[0030] determining, according to the phase of the target light, structural parameters of the Bragg grating corresponding to the phase of the target light from among the plurality of preparation parameters;

[0031] The phase of the target light and the corresponding structural parameters of the Bragg grating are determined as the target preparation parameters.

[0032] In a third aspect, the present application provides a device for determining preparation parameters of a holographic optical element, comprising:

[0033] an acquisition module, configured to acquire a plurality of detection data of the optical holographic element in a target usage scenario, wherein the detection data is detection data within a user's eye box obtained by simulating parameters in the target usage scenario, and any two of the plurality of simulation parameters correspond to different Bragg grating periods of the holographic optical element;

[0034] The processing module is configured to determine, from the plurality of detection data, a plurality of target detection data in which rainbow patterns do not exist within the user's eye box; and determine a plurality of preparation parameters of the holographic optical element according to target simulation parameters corresponding to the plurality of target detection data.

[0035] In a fourth aspect, the present application provides a device for preparing a holographic optical element, comprising:

[0036] a determination module, configured to determine a target usage scenario of the holographic optical element and obtain a scenario parameter corresponding to the target usage scenario; and determine, based on the scenario parameter, a target preparation parameter from a plurality of preparation parameters corresponding to the target usage scenario, the plurality of preparation parameters being obtained according to the method described in any one of the first aspects;

[0037] A preparation module is used to prepare the holographic optical element using target preparation parameters.

[0038] In a fifth aspect, the present application provides a computer-readable storage medium having computer-executable instructions stored thereon. When the computer-executable instructions are executed by a processor, the method described in the first aspect or the second aspect is implemented.

[0039] The computer-readable storage medium provided in the embodiment of the present application can execute the technical solutions in the above method embodiments, and its beneficial effects are similar and will not be repeated here.

[0040] In a sixth aspect, the present application provides a computer program product, comprising a computer program, which implements the method described in the first aspect or the second aspect when executed by a processor.

[0041] The computer program product provided in the embodiment of the present application can execute the technical solutions in the above method embodiments, and its beneficial effects are similar, which will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the implementation methods in the embodiments of the present application or related technologies, the following is a brief introduction to the drawings required for use in the embodiments or related technology descriptions. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0043] Figure 1A schematic diagram showing the principle of a holographic optical element provided in an embodiment of the present application being used as a holographic lens to record information;

[0044] Figure 2 A schematic diagram of the principle of a holographic optical element provided in an embodiment of the present application as a holographic lens to reproduce information;

[0045] Figure 3 A schematic diagram of the ARHUD system provided in an embodiment of the present application;

[0046] Figure 4 A schematic diagram of the internal structure of a holographic optical element provided in an embodiment of the present application;

[0047] Figure 5 A schematic flow chart of a method for determining preparation parameters of a holographic optical element provided in an embodiment of the present application;

[0048] Figure 6 A schematic diagram of a simulation scenario provided in an embodiment of the present application;

[0049] Figure 7 A schematic diagram of detecting the intensity distribution of light beams of different wavelengths at different angles using a far-field monitor provided in an embodiment of the present application;

[0050] Figure 8 A schematic diagram of the angle and intensity distribution of light beams of multiple wavelengths provided in an embodiment of the present application;

[0051] Figure 9 A schematic diagram of the angle and intensity distribution of another light beam with multiple wavelengths provided in an embodiment of the present application;

[0052] Figure 10 A schematic diagram of angle and intensity distribution of light beams of multiple wavelengths provided in another embodiment of the present application;

[0053] Figure 11 A schematic flow chart of a method for preparing a holographic optical element provided in an embodiment of the present application;

[0054] Figure 12 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0055] In order to make the purpose, implementation mode and advantages of the present application clearer, the exemplary implementation mode of the present application will be clearly and completely described below in conjunction with the drawings in the exemplary embodiments of the present application. Obviously, the described exemplary embodiments are only part of the embodiments of the present application, not all of the embodiments.

[0056] All other embodiments derived by persons of ordinary skill in the art based on the exemplary embodiments described herein without inventive effort are within the scope of protection of the claims appended hereto. Furthermore, although the disclosure herein is presented based on one or more exemplary embodiments, it should be understood that each aspect of the disclosure may constitute a complete embodiment on its own.

[0057] It should be noted that the brief descriptions of terms in this application are only for the purpose of facilitating the understanding of the embodiments described below, and are not intended to limit the embodiments of this application. Unless otherwise specified, these terms should be understood according to their ordinary and usual meanings.

[0058] In the specification and claims of this application and the drawings, the terms "first," "second," "third," etc. are used to distinguish similar or similar objects or entities, and are not necessarily intended to limit a particular order or precedence, unless otherwise indicated. It should be understood that the terms used in this manner are interchangeable under appropriate circumstances, for example, the embodiments of this application can be implemented in an order other than those shown or described in the drawings.

[0059] In addition, the terms "comprises" and "comprising" and any variations thereof are intended to cover but not exclude inclusion, for example, a product or device comprising a list of components is not necessarily limited to those components expressly listed but may include other components not expressly listed or inherent to such product or device.

[0060] The term "module" as used in this application refers to any known or later developed hardware, software, firmware, artificial intelligence, fuzzy logic, or combination of hardware and / or software code that is capable of performing the functions associated with that element.

[0061] The working principle of holographic optical elements is holographic lens. Holographic lens means that the information of the lens is recorded in a three-dimensional photosensitive material in a "holographic" way, so it is called a holographic lens. The three-dimensional photosensitive material is an organic material whose refractive index changes when it is irradiated with light of a certain intensity, that is, after exposure. The working principle of holographic optical elements as holographic lenses can be found in Figure 1 As shown, Figure 1 A schematic diagram of the principle of using a holographic optical element as a holographic lens to record information provided in an embodiment of the present application.

[0062] like Figure 1As shown in Figure 1, interference fringes are recorded in the holographic lens by interfering a reference beam (a parallel light wave without lens information) with an object beam (spherical waves, a focused spherical wave with lens information). The reference beam can be a parallel light wave without lens information, and the object beam can be a focused spherical wave with lens information.

[0063] Figure 2 A schematic diagram of the principle of a holographic optical element provided in an embodiment of the present application being used as a holographic lens to reproduce information.

[0064] like Figure 2 As shown, when the reproduction light beam is incident on the holographic optical element at the angle and wavelength of the reference light, the holographic optical element will exhibit the function of the recorded lens, converting the incident parallel light reproduction light beam into a reconstructed focused spherical wave, thereby reproducing the image.

[0065] All optical components can be used in the ARHUD system. The schematic diagram of the ARHUD system can be as follows: Figure 3 As shown, Figure 3 Schematic diagram of the ARHUD system provided in an embodiment of the present application.

[0066] like Figure 3 As shown, the laser projection module can emit a light beam containing vehicle information. The light beam emitted by the laser projection module passes through a reflector and a diffuser and is incident on the holographic optical element of the front windshield. Since the working principle of the holographic optical element is a volume holographic lens, its function is equivalent to a reflective free-form mirror. Therefore, the light beam incident on the holographic optical element can be diffracted and converged into the driver's eye box, so that the driver can see the vehicle information by looking up.

[0067] The eye box range refers to the space in which the user's pupil can move to obtain complete image information. Figure 3 In the figure, the eye box range refers to the movable space in which the driver's pupil can obtain complete image information.

[0068] Vehicle information may include vehicle speed, speed limit, steering action, lane departure, guide lines and other information. The specific information can be set according to the actual situation of the vehicle.

[0069] The structure of the holographic optical element attached to the front windshield of the vehicle can be seen in Figure 4 As shown, Figure 4 A schematic diagram of the internal structure of a holographic optical element provided in an embodiment of the present application.

[0070] like Figure 4As shown, the thickness of the holographic optical element is d, and the Bragg grating structure is composed of alternating regions with a refractive index of n0 and regions with a refractive index of n1=n0+Δ, and the sum of the thicknesses of the regions with the two refractive indices is V.

[0071] The laser emitted by the laser emission module is irradiated onto the Bragg grating as the reproduced light. The Bragg grating is a periodic microstructure that performs Bragg grating diffraction on the incident light beam, splitting the light beam into multiple beams and recombining them to form a diffraction pattern, that is, an image containing vehicle information.

[0072] However, the Bragg grating structure of a holographic optical element has a period length smaller than the wavelength of light, which disperses sunlight and other broad-spectrum ambient light, creating noticeable rainbow patterns on the holographic optical element. This pattern can affect the resulting image and potentially compromise driving safety. In other scenarios, the rainbow patterns produced by the full range of optical elements can also affect the resulting image, resulting in a poor user experience.

[0073] Based on this, an embodiment of the present application provides a method for determining parameters of a holographic optical element. The method determines whether rainbow patterns exist within the user's eyebox using multiple detection data within the user's eyebox, thereby determining target detection data without rainbow patterns from the multiple detection data, and determining target simulation parameters used to obtain the target detection data as preparation parameters for the holographic optical element. In this way, the holographic optical element with this structure can be used in an ARHUD system, i.e., attached to the front windshield of a vehicle, so that the image formed by the holographic optical element has fewer or no rainbow patterns within the user's eyebox, thereby improving the user experience.

[0074] Figure 5 This is a flow chart of a method for determining the preparation parameters of a holographic optical element provided in an embodiment of the present application. The printing method can be executed by software and / or hardware devices. For example, the hardware device can be a device for determining the preparation parameters of a holographic optical element, and the device for determining the preparation parameters of a holographic optical element can be a terminal or a processing chip in the terminal. For example, see Figure 5 As shown, the method for determining the preparation parameters of the holographic optical element may include:

[0075] S501. Acquire multiple detection data of the holographic optical element in a target usage scenario, where the detection data is detection data within a user's eye box obtained by simulating parameters in the target usage scenario, and any two of the multiple simulation parameters correspond to different structural parameters of the Bragg grating of the holographic optical element.

[0076] The usage scenarios of holographic optical elements may include ARHUD systems, AR glasses and other scenarios, which are not limited in the embodiments of the present application.

[0077] The structural parameters of the Bragg grating of the holographic optical element include the Bragg grating period and tilt angle of the holographic optical element.

[0078] The target usage scenario described in the embodiments of the present application can be an ARHUD system or AR glasses, and the embodiments of the present application do not limit this.

[0079] For example, the plurality of detection data may be detection data within the user's eye box obtained by simulating the target usage scenario with different simulation parameters. The detection data may be used to determine whether rainbow lines appear within the user's eye box.

[0080] S502 : Determine, among the plurality of detection data, a plurality of target detection data in which rainbow patterns do not exist within the user's eye box.

[0081] Exemplarily, the detection data may include the corresponding intensities of light beams of multiple wavelengths at multiple angles. When determining, among the multiple detection data, multiple target detection data indicating that rainbow patterns do not exist within the user's eye box, the maximum intensity of the light beam of each wavelength in the detection data may be determined for each detection data, and the center angle corresponding to the intensity maximum may be determined to obtain multiple intensity maxima and multiple center angles; the difference between the center angles of any two light beams of wavelengths may be calculated to obtain multiple first differences; the difference between the maximum intensity of the light beams of any two wavelengths may be calculated to obtain multiple second differences; if the multiple first differences are all less than a first preset value, and / or if any of the multiple second differences is greater than a second preset value, then the detection data is determined to be target detection data indicating that rainbow patterns do not exist within the user's eye box, and multiple target detection data are obtained.

[0082] The first preset value and the second preset value may be pre-set, and this embodiment of the present application does not limit this.

[0083] It is understood that if the detection data within the user's eye box contains rainbow patterns, it is possible that the maximum intensities of light beams of different wavelengths are similar, but the center angles corresponding to the maximum intensities are located at different positions. If the center angles of light beams of different wavelengths are relatively concentrated, then rainbow patterns will not exist within the user's eye box. Therefore, if the multiple first difference values ​​are all less than the first preset value, it can be determined that the corresponding detection parameters are target detection data without rainbow patterns.

[0084] It is understood that if, among the maximum intensities of light beams of different wavelengths detected within the user's eyebox, the maximum intensity of one or more wavelengths is significantly greater than the maximum intensities of light beams of other wavelengths, rainbow streaks will not be present within the user's eyebox. Therefore, if any of the multiple second difference values ​​is greater than the second preset value, the corresponding detection data can be determined to be target detection data without rainbow streaks.

[0085] In this way, whether rainbow stripes exist within the user's eye box is determined based on the distribution of intensity maxima and central angles of different wavelengths after passing through the holographic optical element. Therefore, target detection data without rainbow stripes can be determined from multiple detection data.

[0086] S503: Determine multiple preparation parameters of the holographic optical element according to target simulation parameters corresponding to the multiple target detection data.

[0087] Since the target simulation parameters correspond to target detection data without rainbow patterns, and the target detection data is detected in the target usage scenario, when a holographic optical element is prepared using any one of a plurality of preparation parameters, the obtained holographic optical element will not have rainbow patterns within the user's eye box during use.

[0088] Exemplarily, the simulation parameters may include the incident angle of visible light and the structural parameters of the Bragg grating of the holographic optical element. When determining multiple preparation parameters of the holographic optical element based on the target simulation parameters corresponding to the target detection data, the target incident angle of visible light corresponding to each target detection data in the multiple target detection data and the structural parameters of the target Bragg grating of the holographic optical element may be analyzed and processed to determine the object light phase corresponding to each target detection data, thereby obtaining multiple object light phases; and the multiple object light phases and the multiple Bragg grating structural parameters are determined as multiple preparation parameters of the holographic optical element.

[0089] The incident angle of the visible light is the angle between the visible light and the plane where the holographic optical element is located. The visible light can be broad-spectrum visible light, and the wavelength of the visible light can be in the range of 400 nm to 700 nm.

[0090] The analysis and processing of the target incident angle of visible light corresponding to the target detection data and the structural parameters of the target Bragg grating of the holographic optical element may include a K-vector closure analysis method or a light intensity calculation method after light wave interference superposition. The embodiments of the present application do not limit the specific processing method.

[0091] In this way, since the phase of the object light and the structural parameters of the Bragg grating need to be set when preparing the holographic optical element, the phase of the object light and the corresponding structural parameters of the Bragg grating in the preparation parameters determined in the present application are the phase of the object light and the structural parameters of the Bragg grating at which no rainbow patterns exist within the user's eye box. Therefore, when the holographic optical element prepared using the preparation parameters is used, no rainbow patterns exist within the user's eye box, which can improve the user experience.

[0092] Thus, the method for determining preparation parameters for a holographic optical element provided in an embodiment of the present application determines whether rainbow patterns exist within the user's eyebox based on multiple detection data within the user's eyebox, thereby determining target detection data from the multiple detection data as target detection data without rainbow patterns, and determining the target simulation parameters used to obtain the target detection data as the preparation parameters for the holographic optical element. When the obtained preparation parameters are used to prepare a holographic optical element, the prepared holographic optical element will not have rainbow patterns within the user's eyebox during use, thereby improving the user experience. For example, if the prepared holographic optical element is used in a vehicle's ARHUD system, it can improve driver safety during driving.

[0093] In the embodiment of the present application, a plurality of detection data of the optical holographic element in the target usage scenario may be obtained in a simulation scenario. The following describes a method for obtaining the plurality of detection data.

[0094] For example, in a simulation scenario corresponding to a target usage scenario, visible light may be incident on multiple holographic optical elements at multiple incident angles, and the light beams passing through the optical holographic elements may be detected to obtain multiple detection data.

[0095] The simulated scene can be a scene that simulates the target usage scene. Since the appearance of rainbow patterns is mostly caused by visible light irradiating the holographic optical element, simulating with visible light makes the obtained detection data closer to the actual scene, thereby improving the accuracy of the obtained detection data.

[0096] For example, when detecting the light beam after passing through the optical holographic element, a monitor may be used to detect the light beam after passing through the optical holographic element, which is not limited in the embodiments of the present application.

[0097] For example, the detection data may include the corresponding intensities of light beams of multiple wavelengths at multiple angles. When detecting the light beam after passing through the optical holographic element to obtain multiple detection data, the light beam after passing through the optical holographic element may be subjected to far-field detection to obtain the corresponding intensities of the light beams of multiple wavelengths at multiple angles in the far field.

[0098] In this way, since the user's pupil may be far away from the holographic optical element, the detection data obtained by far-field detection is more consistent with the actual use scenario of the holographic optical element, which can further improve the accuracy of the obtained detection data.

[0099] The following describes a method for determining the preparation parameters of a holographic optical element using an ARHUD system as an example. In the following description, the holographic optical element is referred to as a HOE film.

[0100] The method for determining the preparation parameters of the holographic optical element may include the following steps:

[0101] Step 1: In the ARHUD system, simulate the scenario where visible light at different incident angles hits HOE films with different grating periods, and determine the intensity distribution of multiple wavelengths of dispersed light within the driver's eye box at different angles.

[0102] The incident angle of the visible light is the angle between the visible light and the plane where the HOE film is located. The visible light can be broad-spectrum visible light, and the wavelength of the visible light can be in the range of 400 nm to 700 nm.

[0103] Figure 6 A schematic diagram of a simulation scenario provided in an embodiment of the present application.

[0104] like Figure 6 As shown, the inclination angle between the front windshield of the vehicle and the horizontal plane is 23 degrees, and the HOE film is attached to the front windshield of the vehicle. Figure 5 The incident angle of visible light is 67 degrees, which is vertical, that is, perpendicular to the horizontal plane, and can be regarded as the angle of sunlight at noon.

[0105] The embodiments of this application are only Figure 6 The scenarios shown are for illustration purposes only and do not constitute any limitation.

[0106] For example, Figure 6 As shown in the figure, a wide spectrum of visible light with different incident angles can be used to be incident on the HOE film, and a monitor is set on the initial plane parallel to the plane where the front windshield of the vehicle is located to detect the intensity distribution corresponding to different angles in the far field of light beams of different wavelengths. Figure 7 As shown, Figure 7 A schematic diagram of an embodiment of the present application providing a method for detecting the intensity distribution of light beams of different wavelengths at different angles using a far-field monitor.

[0107] exist Figure 7In the HOE film, a Bragg grating structure is formed by alternating regions with a refractive index of n0 = 1.5 and regions with a refractive index of n1 = 1.505, and the sum of the thicknesses of the regions with the two refractive indices is λ / (2nsinθ).

[0108] For example, when simulating the above scenario, electromagnetic simulation software such as FDTD, comsol, and RCWA may be used. The embodiment of the present application does not limit the software used for the simulation.

[0109] It should be noted that by simulating scenarios where visible light at different incident angles impinges on HOE films with different grating periods, the initial plane containing the angles of the multiple wavelengths of the dispersed light beams obtained is parallel to the plane of the vehicle's windshield, while the plane of the eyebox range is perpendicular to the horizontal plane. Therefore, based on the angle between the initial plane and the plane containing the eyebox range, the angles of the multiple wavelengths of the light beams obtained in the initial plane can be converted to the angles of the multiple wavelengths of the light beams within the eyebox range. Furthermore, the converted angles and intensities can be correlated to determine the angle and intensity distribution of the multiple wavelengths of the dispersed light beams within the driver's eyebox range.

[0110] It should be noted that since the structural parameters of the HOE mode include the Bragg grating period and the tilt angle, in the embodiment of the present application, different tilt angles can be simulated by the incident angle of light. Therefore, in the embodiment of the present application, only the Bragg grating period is described.

[0111] For example, the angle and intensity distribution of the light beams of multiple wavelengths obtained by dispersion within the eye box can be found in Figure 8 、 Figure 9 and Figure 10 shown. Figure 8 A schematic diagram of the angle and intensity distribution of light beams of multiple wavelengths provided in an embodiment of the present application. Figure 9 A schematic diagram of the angle and intensity distribution of another type of light beams with multiple wavelengths provided in an embodiment of the present application. Figure 10 A schematic diagram of the angle and intensity distribution of light beams of multiple wavelengths provided in an embodiment of the present application.

[0112] Step 2: Determine multiple target incident angles and multiple target Bragg grating periods of visible light without rainbow fringes based on the intensity distribution of the light beams of multiple wavelengths at different angles.

[0113] Exemplarily, for the angle and intensity distributions of multiple wavelengths obtained under any visible light incident angle and any Bragg grating period, the maximum intensity of each wavelength and the center angle corresponding to the intensity maximum of each wavelength are determined, and the difference between the center angles of any two wavelengths is calculated to obtain multiple first differences. Furthermore, the difference between the intensity maximums of any two wavelengths is calculated to obtain multiple second differences. If the multiple first differences are all less than a first preset value, and / or if a second difference is greater than a second preset value among the multiple second differences, then the visible light angle and Bragg grating period under this scenario are determined to be multiple target incident angles and multiple target Bragg grating periods for visible light without rainbow fringes.

[0114] As mentioned above Figure 8 As shown, the positions of the center angles of different wavelengths are different, that is, the difference between the center angles of any two wavelengths is greater than the first preset value, and the maximum intensities of different wavelengths are similar, that is, the difference between the maximum intensities of any two wavelengths is less than the second preset value. Therefore, Figure 8 The corresponding incident angle of visible light and Bragg grating period are the incident angle and Bragg grating period at which rainbow fringes exist.

[0115] As mentioned above Figure 9 As shown, the positions of the center angles of different wavelengths are close, that is, the difference between the center angles of any two wavelengths is less than the first preset value, and the maximum intensity values ​​of different wavelengths are close, that is, the difference between the maximum intensity values ​​of any two wavelengths is less than the second preset value. Therefore, Figure 9 The corresponding incident angle of visible light and Bragg grating period are the incident angle and Bragg grating period at which no rainbow fringes exist.

[0116] As mentioned above Figure 10 As shown, the positions of the center angles of different wavelengths are different, that is, the difference between the center angles of any two wavelengths is greater than the first preset value, and the maximum intensity values ​​of different wavelengths are different, that is, the difference between the maximum intensity values ​​of any two wavelengths is greater than the second preset value. Therefore, Figure 10 The corresponding incident angle of visible light and Bragg grating period are the incident angle and Bragg grating period at which no rainbow fringes exist.

[0117] Step 3: Calculate and obtain phase distributions of multiple object beams based on multiple target incident angles and multiple target Bragg grating periods.

[0118] Exemplarily, the incident angle and wavelength of the object light can be calculated based on multiple target incident angles and multiple target Bragg grating periods through the K-vector closure analysis method or the light intensity calculation method after light wave interference superposition, and the phase distribution of the object light can be determined based on the incident angle and wavelength of the object light.

[0119] Step 4: Store the multiple object light phase distributions and the multiple target Bragg gratings in a preparation parameter library.

[0120] Exemplarily, a plurality of object light phase distributions and corresponding target Bragg gratings are stored in a preparation parameter library, so that the parameters in the preparation parameter library can be used to subsequently fabricate the HOE film.

[0121] After the parameters of the holographic optical element are determined by the above method, the holographic optical element can be manufactured using the determined parameters. Figure 11 The following is a flow chart of a method for preparing a holographic optical element provided in an embodiment of the present application. Figure 11 As shown, the method for preparing a holographic optical element may include the following steps:

[0122] S1101: Determine a target usage scenario of a holographic optical element, and obtain scene parameters corresponding to the target usage scenario.

[0123] Exemplarily, the scene parameters may include the wavelength, spectral width, imaging distance, phase distribution of the object light, parameters of the reflector used in the scene, parameters of the prism, parameters of the lens, etc. The specific parameters can be set according to the actual situation of the target usage scenario, and the embodiments of the present application are not limited to this.

[0124] S1102. Determine a target preparation parameter from a plurality of preparation parameters corresponding to a target usage scenario according to the scenario parameter.

[0125] The multiple preparation parameters are obtained according to the method for determining the preparation parameters of the holographic optical element, which can be found in the above embodiments and will not be described in detail here.

[0126] Exemplarily, the scene parameters may include the phase of the target object light, and the preparation parameters include the phases of multiple object lights and the corresponding Bragg grating periods; when determining the target preparation parameters from the multiple preparation parameters corresponding to the target usage scene based on the scene parameters, the Bragg grating period corresponding to the phase of the target object light can be determined from the multiple preparation parameters based on the phase of the target object light; the phase of the target object light and the corresponding Bragg grating period are determined as the target preparation parameters.

[0127] Exemplarily, the phase of the target object light can be a free-form surface type continuous object light phase distribution calculated by optical design software such as Zemax, odeV, lighttools, or optical design methods such as iterative design. The continuous object light phase distribution includes the phases of multiple object lights, that is, the phase of the target object light includes the phases of multiple object lights.

[0128] According to the phases of multiple object beams in the continuous object beam phase distribution and the phase distribution of the object beam in the preparation parameters, the Bragg grating period corresponding to the phases of the multiple object beams can be determined in the preparation parameters, thereby determining the target preparation parameters of the holographic optical element.

[0129] It should be noted that since the above method for determining the fabrication parameters is based on simulation modeling, considering that a large amount of simulation data may place higher demands on the electronic equipment, and that the larger the area of ​​the holographic optical element, the more data the simulation requires, simulation can be performed on holographic optical elements with smaller areas.

[0130] Therefore, after obtaining the phase distribution of the free-form surface continuous object light, the phase distribution of the object light can be discretized to obtain multiple phase distributions of the object light, so that the corresponding Bragg grating period can be determined according to the phase distributions of the multiple object lights.

[0131] For example, when discretizing the phase distribution of the object light, it can be performed based on parameters such as the area of ​​the holographic optical element used in the simulation when determining the preparation parameters, so as to match the Bragg grating period.

[0132] In this way, the corresponding Bragg grating period is determined by the phase distribution of the object light in the actual use scene, so that when a holographic optical element is prepared according to the phase of the object light and the corresponding Bragg grating period, the obtained holographic optical element will not have rainbow fringes within the user's eye box.

[0133] S1103. Prepare a holographic optical element using target preparation parameters.

[0134] For example, the method for preparing a holographic optical element using target preparation parameters can be referred to the above Figure 1 As shown, no further details are given here.

[0135] In this way, according to the scene parameters in the actual target usage scenario, the target preparation parameters are determined from multiple preparation parameters, and the target preparation parameters are used to prepare the holographic optical element. Since the multiple preparation parameters are obtained in the absence of rainbow patterns, the prepared holographic optical element does not have rainbow patterns within the eye box range of the user in the target usage scenario.

[0136] It should be noted that in the above embodiments, only the Bragg grating period of the holographic optical element is involved in the calculation process, and its tilt angle is not involved. This is because the tilt angle has been taken into account in the process of simulating data, or the tilt angle is set to be the same. Therefore, the method described in the embodiments of the present application can be implemented by the Bragg grating period.

[0137] Figure 12This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. Figure 12 As shown, the electronic device 1200 may include: at least one processor 1201 and a memory 1202 .

[0138] The memory 1202 is used to store programs. Specifically, the programs may include program codes, and the program codes include computer operating instructions.

[0139] The memory 1202 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0140] The processor 1201 is used to execute the computer-executable instructions stored in the memory 1202 to implement the data processing method described in the aforementioned method embodiment. Among them, the processor 1201 may be a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application. Specifically, when implementing the method described in the aforementioned method embodiment, the electronic device may be, for example, an electronic device with processing capabilities, such as a terminal or a server.

[0141] Optionally, the electronic device 1200 may further include a communication interface 1203. In a specific implementation, if the communication interface 1203, the memory 1202, and the processor 1201 are implemented independently, the communication interface 1203, the memory 1202, and the processor 1201 may be interconnected via a bus and communicate with each other. The bus may be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus. Buses can be classified as address buses, data buses, control buses, etc., but this does not mean that there is only one bus or only one type of bus.

[0142] Optionally, in a specific implementation, if the communication interface 1203, the memory 1202 and the processor 1201 are integrated on a chip, the communication interface 1203, the memory 1202 and the processor 1201 can complete communication through an internal interface.

[0143] The present application also provides a computer-readable storage medium, which may include: a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a disk or an optical disk, and other media that can store program codes. Specifically, the computer-readable storage medium stores program instructions, and the program instructions are used for the methods in the above embodiments.

[0144] The present application also provides a program product, comprising execution instructions stored in a readable storage medium. At least one control module of a display device can read the execution instructions from the readable storage medium, and the at least one control module executes the execution instructions to cause the display device to implement the methods for determining preparation parameters of a holographic optical element provided in the various embodiments described above.

[0145] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

[0146] For ease of explanation, the above description has been made with reference to specific embodiments. However, the above exemplary discussion is not intended to be exhaustive or to limit the embodiments to the specific forms disclosed above. Based on the above teachings, various modifications and variations are possible. The above embodiments are selected and described to better explain the principles and practical applications, so that those skilled in the art can better utilize the embodiments and various different variations of the embodiments suitable for specific use considerations.

Claims

1. A method for determining preparation parameters of a holographic optical element, characterized in that: include: Acquiring a plurality of detection data of the optical holographic element in a target usage scenario, wherein the detection data is detection data within a user's eye box obtained by simulating parameters in the target usage scenario, wherein any two of the plurality of simulation parameters correspond to different structural parameters of the Bragg grating of the holographic optical element; Determining, among the plurality of detection data, a plurality of target detection data in which rainbow patterns do not exist within the user's eye box range; A plurality of preparation parameters of the holographic optical element are determined according to the target simulation parameters corresponding to the plurality of target detection data.

2. The method according to claim 1, characterized in that The detection data includes the intensity of light beams of multiple wavelengths at multiple angles; The determining of multiple target detection data in which rainbow patterns do not exist within the user's eye box range among the multiple detection data includes: For each of the detection data, determining the maximum intensity of the light beam of each wavelength in the detection data, and determining the center angle corresponding to the intensity maximum, to obtain multiple intensity maximum values ​​and multiple center angles; Calculating the difference between the center angles of light beams of any two wavelengths to obtain a plurality of first differences; Calculating the difference between the maximum intensities of the light beams of any two wavelengths to obtain a plurality of second difference values; If the multiple first difference values ​​are all smaller than the first preset value, and / or there is a value greater than the second preset value among the multiple second difference values, it is determined that the detection data is target detection data in which no rainbow pattern exists within the user's eye box range, and multiple target detection data are obtained.

3. The method according to claim 2, characterized in that The simulation parameters include an incident angle of visible light and structural parameters of a Bragg grating of a holographic optical element. The determining of a plurality of preparation parameters of the holographic optical element based on the target simulation parameters corresponding to the target detection data includes: Analyzing and processing the target incident angle of visible light corresponding to each target detection data and the structural parameters of the target Bragg grating of the holographic optical element in the plurality of target detection data, determining the object light phase corresponding to each target detection data, and obtaining a plurality of object light phases; The phases of the plurality of object lights and the structural parameters of the plurality of target Bragg gratings are determined as a plurality of preparation parameters of the holographic optical element.

4. The method according to any one of claims 1 to 3, characterized in that The method further comprises: In a simulation scenario corresponding to the target usage scenario, visible light is incident on a plurality of holographic optical elements at a plurality of incident angles, and the light beams passing through the optical holographic elements are detected to obtain a plurality of detection data.

5. The method according to claim 4, characterized in that The detection data includes the intensity of light beams of multiple wavelengths at multiple angles; The light beam after passing through the optical holographic element is detected to obtain a plurality of detection data, including: The light beam passing through the optical holographic element is subjected to far-field detection to obtain the corresponding intensities of light beams of multiple wavelengths at multiple angles in the far field.

6. A method for preparing a holographic optical element, characterized in that: The method comprises: Determining a target usage scenario of the holographic optical element and obtaining scene parameters corresponding to the target usage scenario; Determining, according to the scenario parameters, a target preparation parameter from a plurality of preparation parameters corresponding to the target usage scenario, wherein the plurality of preparation parameters are obtained according to the method of any one of claims 1 to 5 above; The holographic optical element is produced using target production parameters.

7. The method according to claim 6, characterized in that The scene parameters include the phase of the target object light, and the preparation parameters include the phases of multiple object lights and the structural parameters of the corresponding Bragg gratings; Determining a target preparation parameter from a plurality of preparation parameters corresponding to the target usage scenario according to the scenario parameter includes: determining, according to the phase of the target light, structural parameters of the Bragg grating corresponding to the phase of the target light from among the plurality of preparation parameters; The phase of the target light and the corresponding structural parameters of the Bragg grating are determined as the target preparation parameters.

8. An electronic device, characterized in that: comprising a memory and a processor; wherein, The memory is used to store computer programs; The processor is configured to read the computer program stored in the memory and execute the method according to any one of claims 1 to 7 above according to the computer program in the memory.

9. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer-executable instructions, and when the computer-executable instructions are executed by a processor, the method according to any one of claims 1 to 7 is implemented.

10. A computer program product, characterized in that The invention comprises a computer program, which implements the method according to any one of claims 1 to 7 when executed by a processor.

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