Refractive index adjustment method, device, smart glasses and storage medium

Abstract

This application relates to the field of optical technology and discloses a method, device, smart glasses, and storage medium for adjusting refractive index. The method is applied to smart glasses equipped with a liquid crystal lens. The method includes: acquiring the current surface temperature and target refractive index of the liquid crystal lens; querying a preset mapping table based on the target refractive index and the current surface temperature to obtain a target lens driving voltage; the preset mapping table is a mapping table between different test lens driving voltages and corresponding test refractive indices at different test lens surface temperatures; and driving the liquid crystal lens according to the target lens driving voltage to adjust the refractive index of the liquid crystal lens to the target refractive index. Compared to existing methods, this application can directly query a preset mapping relationship for refractive index adjustment, eliminating the need for a heating film, thereby improving the thinness and lightness of the smart glasses.

Description

Technical Field

[0001] This application relates to the field of optical technology, and in particular to a method, device, smart glasses, and storage medium for adjusting refractive index. Background Technology

[0002] Currently, with the development of technology, smart glasses (such as Augmented Reality (AR) glasses) are gradually entering people's lives. To achieve refractive index adjustment and thus meet the needs of users with different vision, AR glasses generally use liquid crystal lenses as lenses. At normal ambient temperatures (e.g., 20°C), different target refractive indices are set with corresponding driving voltages. By applying the corresponding driving voltage to the liquid crystal lens, the refractive index is adjusted to the target refractive index. However, at low temperatures (e.g., -10°C), liquid crystal lenses experience driving voltage mismatch, meaning that the target refractive index achieved under the same driving voltage will decrease. Therefore, if the driving voltage corresponding to the target refractive index under normal conditions continues, the adjusted target refractive index will be inaccurate, resulting in unsatisfactory display effects from the AR glasses.

[0003] To mitigate the impact of low temperatures on liquid crystal lenses, existing methods typically involve applying a heating film to the lens surface. This film heats the lens surface to ambient temperature, thus mitigating the effects of low temperatures on lens performance to some extent. However, this method increases the lens thickness, making it difficult to meet the demand for thinner and lighter smart glasses. Summary of the Invention

[0004] The main objective of this application is to provide a refractive index adjustment method, device, smart glasses, and storage medium, aiming to solve the technical problem that existing methods of reducing the impact of low temperature on liquid crystal lenses by setting a heating film result in increased thickness of the liquid crystal lens and poor thinning effect.

[0005] To achieve the above objectives, this application provides a refractive index adjustment method, which is applied to smart glasses equipped with a liquid crystal lens, and the method includes:

[0006] Obtain the current lens surface temperature and target refractive index of the liquid crystal lens;

[0007] The target lens driving voltage is obtained by querying a preset mapping table based on the target refractive index and the current lens surface temperature. The preset mapping table is a mapping table between different test lens driving voltages and corresponding test refractive indices at different test lens surface temperatures.

[0008] The liquid crystal lens is driven according to the target lens driving voltage so that the refractive index of the liquid crystal lens is adjusted to the target refractive index.

[0009] In one embodiment, before the step of obtaining the current lens surface temperature and target refractive index of the liquid crystal lens, the method further includes:

[0010] The liquid crystal lens is heated according to a preset temperature step, and the liquid crystal lens is driven at the surface temperature of each test lens so that the refractive index of the liquid crystal lens reaches the test refractive index.

[0011] The driving voltage of the test lens is obtained based on the driving result, and a mapping table is constructed based on the driving voltage of the test lens, the surface temperature of the test lens, and the test refractive index.

[0012] In one embodiment, the liquid crystal lens is divided according to a preset lens partition;

[0013] The step of obtaining the current lens surface temperature of the liquid crystal lens includes:

[0014] Obtain the current surface temperature of each lens partition in the liquid crystal lens;

[0015] The step of obtaining the target lens driving voltage by querying a preset mapping table based on the target refractive index and the current lens surface temperature includes:

[0016] Determine whether any of the current temperature differences between the surface temperatures of each current partition are higher than a preset temperature difference threshold.

[0017] If none of the current temperature differences are higher than the preset temperature difference threshold, the current lens surface temperature is determined based on the surface temperature of each current partition.

[0018] The target lens driving voltage is obtained by querying a preset mapping table based on the target refractive index and the current lens surface temperature.

[0019] In one embodiment, after the step of determining whether any of the current temperature differences between the surface temperatures of each of the current partitions exceeds a preset temperature difference threshold, the method further includes:

[0020] If any of the current temperature differences is higher than the preset temperature difference threshold, the target partition driving voltage corresponding to each preset lens partition is obtained by querying the preset mapping relationship table according to the target refractive index and the surface temperature of each current partition.

[0021] The step of driving the liquid crystal lens according to the target lens driving voltage includes:

[0022] The preset lens partitions are driven according to the target partition driving voltage.

[0023] In one embodiment, the step of determining whether any of the current temperature differences between the surface temperatures of each current partition exceeds a preset temperature difference threshold includes:

[0024] Obtain the current ambient temperature of the smart glasses;

[0025] The predicted surface temperature of each preset lens partition is obtained by using a Kalman filter to predict the current ambient temperature and the surface temperature of each current partition.

[0026] Determine whether any of the predicted temperature differences between the surface temperatures of the predicted zones exceed a preset temperature difference threshold.

[0027] In one embodiment, after obtaining the current ambient temperature of the smart glasses, the method further includes:

[0028] When the current ambient temperature is lower than the preset normal temperature, the initial lens driving voltage of the liquid crystal lens is obtained by querying the initial mapping relationship table according to the preset normal temperature and the target refractive index. The initial mapping relationship table is a mapping relationship table between different normal lens driving voltages and corresponding normal refractive indices at the preset normal temperature.

[0029] The reference driving voltage is determined based on the current ambient temperature, the preset normal temperature, and the initial lens driving voltage;

[0030] The step of driving the liquid crystal lens according to the target lens driving voltage includes:

[0031] A drive compensation voltage is determined based on the reference drive voltage and the target lens drive voltage. The reference drive voltage is then compensated using the drive compensation voltage, and the liquid crystal lens is driven according to the compensated reference drive voltage.

[0032] In one embodiment, after obtaining the current ambient temperature of the smart glasses, the method further includes:

[0033] When the current ambient temperature is lower than the preset normal temperature, obtain the initial driving frequency corresponding to the preset normal temperature;

[0034] The step of driving the liquid crystal lens according to the target lens driving voltage includes:

[0035] The target driving frequency is determined based on the current ambient temperature, the preset normal temperature, and the initial driving frequency, and the liquid crystal lens is driven using the target driving frequency according to the target lens driving voltage.

[0036] Furthermore, to achieve the above objectives, embodiments of this application also propose a refractive index adjustment device, the device comprising:

[0037] The parameter acquisition module is used to acquire the current lens surface temperature and target refractive index of the liquid crystal lens;

[0038] The voltage query module is used to query a preset mapping relationship table based on the target refractive index and the current lens surface temperature to obtain the target lens driving voltage. The preset mapping relationship table is a mapping relationship table between different test lens driving voltages and corresponding test refractive indices at different test lens surface temperatures.

[0039] A lens driving module is used to drive the liquid crystal lens according to the target lens driving voltage, so as to adjust the refractive index of the liquid crystal lens to the target refractive index.

[0040] Furthermore, to achieve the above objectives, this application also proposes a smart glasses, which includes: a liquid crystal lens, a memory, a processor, and a refractive index adjustment program stored in the memory and executable on the processor. When the refractive index adjustment program is executed by the processor, it implements the steps of the refractive index adjustment method described above.

[0041] Furthermore, to achieve the above objectives, this application also proposes a storage medium storing a refractive index adjustment program, which, when executed by a processor, implements the steps of the refractive index adjustment method described above.

[0042] This application provides a refractive index adjustment method, apparatus, smart glasses, and storage medium. The method is applied to smart glasses equipped with a liquid crystal lens. The method includes: acquiring the current lens surface temperature and target refractive index of the liquid crystal lens; querying a preset mapping table based on the target refractive index and the current lens surface temperature to obtain a target lens driving voltage, wherein the preset mapping table is a mapping table between different test lens driving voltages and corresponding test refractive indices at different test lens surface temperatures; and driving the liquid crystal lens according to the target lens driving voltage to adjust the refractive index of the liquid crystal lens to the target refractive index.

[0043] This application pre-constructs a mapping table between different test lens driving voltages and corresponding test refractive indices at different test lens surface temperatures. In actual use, the current lens surface temperature and target refractive index of the liquid crystal lens are first obtained. The target lens driving voltage is then obtained by consulting the pre-constructed mapping table based on the target refractive index and current lens surface temperature. The liquid crystal lens is then driven according to this target lens driving voltage, thereby achieving the target refractive index. Compared to existing methods that require heating the liquid crystal lens to a normal temperature using a heating film at low temperatures, and then determining the corresponding driving voltage based on the target refractive index at that temperature, this application allows for setting the mapping relationship between different test driving voltages and test refractive indices at different current lens surface temperatures. Therefore, in actual use, the pre-constructed mapping relationship can be directly consulted for refractive index adjustment, eliminating the need for a heating film and thus improving the thinness and lightness of smart glasses. Attached Figure Description

[0044] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0045] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 This is a schematic diagram of the smart glasses structure of the hardware operating environment involved in the embodiments of this application;

[0047] Figure 2 This is a flowchart illustrating the first embodiment of the refractive index adjustment method of this application;

[0048] Figure 3 This is a flowchart illustrating the second embodiment of the refractive index adjustment method of this application;

[0049] Figure 4 This is a flowchart illustrating the third embodiment of the refractive index adjustment method of this application;

[0050] Figure 5 This is a structural block diagram of the first embodiment of the refractive index adjustment device of this application.

[0051] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0052] It should be understood that the specific embodiments described herein are merely illustrative of the technical solutions of this application and are not intended to limit this application.

[0053] Reference Figure 1 , Figure 1 This is a schematic diagram of the smart glasses structure of the hardware operating environment involved in the embodiments of this application.

[0054] like Figure 1 As shown, the smart glasses may include: a processor 1001, such as a central processing unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. The communication bus 1002 is used to enable communication between these components. The user interface 1003 may be connected to a display screen. Optionally, the user interface 1003 may include a standard wired interface or a wireless interface; in this application, the wired interface of the user interface 1003 may be a USB interface. The network interface 1004 may optionally include a standard wired interface or a wireless interface (such as a Wireless-Fidelity (Wi-Fi) interface). The memory 1005 may be high-speed random access memory (RAM) or non-volatile memory (NVM), such as a disk storage device. Optionally, the memory 1005 may also be a storage device independent of the aforementioned processor 1001.

[0055] Those skilled in the art will understand that Figure 1 The structure shown does not constitute a limitation on smart glasses and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0056] like Figure 1 As shown, the memory 1005, which is identified as a computer storage medium, may include an operating system, a network communication module, a user interface module, and a refractive index adjustment program.

[0057] exist Figure 1 In the smart glasses shown, the network interface 1004 is mainly used to connect to the backend server and communicate data with the backend server; the user interface 1003 is mainly used to connect to the user device; the smart glasses call the refractive index adjustment program stored in the memory 1005 through the processor 1001 and execute the steps of the refractive index adjustment method provided in the embodiments of this application.

[0058] It should also be emphasized that the smart glasses in this embodiment may also include a liquid crystal lens, which can be set on the smart glasses at a position corresponding to the user's eyeball, so that the clarity of the image displayed in the user's eyeball can be adjusted by adjusting the refractive index through the liquid crystal lens.

[0059] It should be noted that with the development of technology, smart glasses (such as Augmented Reality (AR) glasses) are gradually entering people's lives. To achieve refractive index adjustment and thus meet the needs of users with different vision, AR glasses generally use liquid crystal lenses as lenses. At normal ambient temperatures (e.g., 20°C), different target refractive indices have corresponding driving voltages. By applying the corresponding driving voltage to the liquid crystal lens, the refractive index is adjusted to the target refractive index. However, at low temperatures (e.g., -10°C), liquid crystal lenses experience driving voltage mismatch, meaning that the target refractive index achieved under the same driving voltage will decrease. Therefore, if the driving voltage corresponding to the target refractive index under normal conditions continues, the adjusted target refractive index will be inaccurate, resulting in unsatisfactory display effects from the AR glasses.

[0060] To mitigate the impact of low temperatures on liquid crystal lenses, existing methods typically involve applying a heating film to the lens surface. This film heats the lens surface to ambient temperature, thus mitigating the effects of low temperatures on lens performance to some extent. However, this method increases the lens thickness, making it difficult to meet the demand for thinner and lighter smart glasses.

[0061] Therefore, to address the aforementioned shortcomings, this embodiment provides a refractive index adjustment method. In this embodiment, a preset mapping table can be pre-constructed between different test lens surface temperatures, different test lens driving voltages, and corresponding test refractive indices. Then, in actual use, the current lens surface temperature and target refractive index of the liquid crystal lens can be obtained first. Based on the target refractive index and the current lens surface temperature, the preset mapping table is consulted to obtain the target lens driving voltage. The liquid crystal lens can then be driven according to this target lens driving voltage, thereby achieving the target refractive index. Compared to existing methods that require heating the liquid crystal lens to a normal temperature using a heating film at low temperatures, and then determining the corresponding driving voltage based on the target refractive index at normal temperature, this embodiment allows for setting a mapping relationship between different test driving voltages and test refractive indices at different current lens surface temperatures. Therefore, in actual use, the preset mapping relationship can be directly consulted for refractive index adjustment, eliminating the need for a heating film and thus improving the thinness and lightness of smart glasses.

[0062] For ease of understanding, the following is combined with Figures 2 to 5 The refractive index adjustment method provided in the embodiments of this application will be described in detail.

[0063] Reference Figure 2 , Figure 2 This is a flowchart illustrating the first embodiment of the refractive index adjustment method of this application. The first embodiment of the refractive index adjustment method of this application is presented as follows: Figure 2 As shown, in this embodiment, the specific method includes:

[0064] Step S10: Obtain the current lens surface temperature and target refractive index of the liquid crystal lens.

[0065] It should be noted that the method in this embodiment can be applied to the aforementioned smart glasses. These smart glasses can be any type of glasses used for display, such as VR glasses. This embodiment does not impose any limitations on this. For ease of understanding, this embodiment and the following embodiments use smart glasses as the execution subject for description. In this embodiment, the smart glasses may include temples and a head-mounted display. The temples are located on both sides of the head-mounted display for the user to wear. The head-mounted display can be used to display images. To adjust the refractive index, liquid crystal lenses can be placed at positions corresponding to the user's eyeballs on the head-mounted display. Refractive index adjustment can be achieved by electrically driving the liquid crystal lenses. The structure of the liquid crystal lenses and their specific positions within the smart glasses can be customized according to actual conditions; this embodiment does not impose any limitations on this.

[0066] It is understood that the aforementioned current lens surface temperature can be the current temperature of the liquid crystal lens surface. This embodiment may also include a liquid crystal cell in the head-mounted display, within which a liquid crystal lens can be housed. A first temperature acquisition component for acquiring the surface temperature of the liquid crystal lens can be mounted on the liquid crystal cell. This first temperature acquisition component can be any device used for temperature acquisition, such as a micro-electro-mechanical systems (MEMS) thermopile sensor array (with an accuracy of ±0.5℃), etc. This embodiment does not impose any limitations on this. Furthermore, in this embodiment, the aforementioned first temperature acquisition component can be positioned at any location where the liquid crystal lens surface temperature is acquired; this embodiment also does not impose any limitations on this.

[0067] In this embodiment, the substrate material of the liquid crystal lens can be a cyclic olefin polymer (COP) with a thickness of 0.3 mm, the liquid crystal material can be MLS-267, the effective refractive index change Δn at 20°C is 0.25, and the thickness of the liquid crystal cell can be 15 micrometers.

[0068] It is also understood that the aforementioned target refractive index can be the refractive index that allows the user to clearly observe the image. In this embodiment, the smart glasses can determine the user's target refractive index before operation, which can be a method preset by the user, or it can be obtained in other ways; this embodiment does not limit this.

[0069] In practical use, when a user uses the aforementioned smart glasses, the smart glasses can obtain the target refractive index corresponding to the user, and can also obtain the surface temperature of the liquid crystal lens through the aforementioned first temperature acquisition component to obtain the current lens surface temperature.

[0070] Step S20: Based on the target refractive index and the current lens surface temperature, query the preset mapping table to obtain the target lens driving voltage. The preset mapping table is a mapping table between different test lens driving voltages and corresponding test refractive indices at different test lens surface temperatures.

[0071] It should be understood that the above-mentioned preset mapping relationship can be stored in this embodiment. The preset mapping relationship can be a mapping relationship table between different test lens driving voltages and corresponding test refractive indices at different test lens surface temperatures, specifically a lookup table (LUT).

[0072] The surface temperature of the test lens can be the surface temperature of the liquid crystal lens when constructing the preset mapping table. The driving voltage of the test lens can be the driving voltage required for the liquid crystal lens to reach the test refractive index at the test lens surface temperature when constructing the preset mapping table. The test refractive index can be the refractive index that the liquid crystal lens needs to reach when constructing the preset mapping table.

[0073] Before using the aforementioned smart glasses, the liquid crystal lens can be tested in advance. This involves testing the lens at different surface temperatures to achieve the required driving voltage for different refractive indices. Multiple sets of data (e.g., 100 sets) can be tested, and the preset mapping relationship can be constructed based on the test results using a model. This model can be a Jones matrix model, or other models; this embodiment does not impose any limitations on it.

[0074] It should be noted that since low temperature has a significant impact on liquid crystal lenses, the surface temperature of the test lens mentioned above can include low temperature, such as between -30℃ and 60℃, or other temperature ranges. This embodiment does not limit this.

[0075] To obtain the aforementioned preset mapping table, specifically before the steps of obtaining the current lens surface temperature and target refractive index of the liquid crystal lens, the following steps are also included:

[0076] Step S01: Heat the liquid crystal lens according to a preset temperature step, and drive the liquid crystal lens at the surface temperature of each test lens so that the refractive index of the liquid crystal lens reaches the test refractive index;

[0077] Step S02: Obtain the driving voltage of the test lens based on the driving result, and construct a mapping table based on the driving voltage of the test lens, the surface temperature of the test lens, and the test refractive index.

[0078] It should be noted that the preset temperature step size can be any size, such as 5°C, and this embodiment uses 5°C for illustration. Furthermore, in order to adjust the surface temperature of the liquid crystal lens, in this embodiment, the smart glasses can be placed in a constant temperature chamber, and the temperature inside the chamber can be adjusted to bring the surface of the liquid crystal lens to the surface temperature of the test lens.

[0079] In practical implementation, the smart glasses can be pre-placed in a constant temperature chamber, and the temperature can be adjusted in preset temperature steps of 5°C to calibrate the liquid crystal lens. The driving voltage is continuously adjusted to achieve the test refractive index at the surface temperature of the test lens, obtaining the driving result. Based on this result, the corresponding test lens driving voltage can be obtained. Then, the surface temperature of each test lens, the test lens driving voltage, and the test refractive index are fitted according to a preset fitting formula to obtain the aforementioned preset mapping relationship table.

[0080] The above-mentioned preset fitting formula can be:

[0081] ;

[0082] Where T is temperature and V is the driving voltage of the test lens. To test the refractive index, These are the coefficients of the temperature-dependent polynomial.

[0083] Therefore, when in use, once the smart glasses determine the current lens surface temperature and target refractive index, they can query the above-mentioned preset mapping relationship to obtain the corresponding target lens driving voltage.

[0084] Step S30: Drive the liquid crystal lens according to the target lens driving voltage to adjust the refractive index of the liquid crystal lens to the target refractive index.

[0085] After obtaining the target lens driving voltage, the target lens driving voltage can be output to the liquid crystal lens, thereby enabling the liquid crystal to achieve the target refractive index. Even when the liquid crystal lens is at a low temperature, because this embodiment tested the low-temperature region when constructing the preset mapping table, the target refractive index can be achieved at low temperatures according to the target lens driving voltage. This reduces the occurrence of driving voltage mismatch, and since no heating film is required, the thinner and lighter design of the smart glasses is improved. Furthermore, since no heating film is required in this embodiment, the operating power consumption of the smart glasses can also be reduced.

[0086] In this embodiment, a preset mapping table can be pre-constructed between different test lens driving voltages and corresponding test refractive indices at different test lens surface temperatures. In actual use, the current lens surface temperature and target refractive index of the liquid crystal lens can be obtained first. Based on the target refractive index and the current lens surface temperature, the preset mapping table is consulted to obtain the target lens driving voltage. Then, the liquid crystal lens can be driven according to this target lens driving voltage, thereby achieving the target refractive index. Compared to existing methods that require heating the liquid crystal lens to a normal temperature using a heating film at low temperatures, and then determining the corresponding driving voltage based on the target refractive index at normal temperature, this embodiment allows for setting the mapping relationship between different test driving voltages and test refractive indices at different current lens surface temperatures. Therefore, in actual use, the preset mapping relationship can be directly consulted for refractive index adjustment, eliminating the need for a heating film and thus improving the thinness and lightness of the smart glasses.

[0087] Reference Figure 3 , Figure 3 This is a flowchart illustrating the second embodiment of the refractive index adjustment method of this application. Based on the first embodiment described above, a second embodiment of the refractive index adjustment method of this application is proposed.

[0088] Considering that different areas on a liquid crystal lens may have different temperatures, in order to reduce phase distortion caused by temperature gradients, therefore... Figure 3 As shown, in this embodiment, the liquid crystal lens is divided according to a preset lens partition;

[0089] The step of obtaining the current lens surface temperature of the liquid crystal lens includes:

[0090] Step S11: Obtain the current surface temperature of each preset lens partition in the liquid crystal lens.

[0091] It should be noted that in this embodiment, the liquid crystal lens is divided according to a preset lens partition. This preset lens partition can be a partitioned area obtained according to any partitioning rule. For example, in this embodiment, the liquid crystal lens can be divided according to a 6×6 electrode array to obtain 36 preset lens partitions. Of course, it can also be divided according to other sizes, and this embodiment does not limit this. Furthermore, each preset lens partition can be driven by an independent voltage.

[0092] In order to obtain a liquid crystal lens with preset lens partitions, in this embodiment, when manufacturing the liquid crystal lens, the electrode partitions can be made of indium tin oxide (ITO) partitioned electrodes, whose sheet resistance can be 20 ohms per square (Ω / sq). A 6×6 array structure can be formed by laser etching process. Of course, other methods can also be used, and this embodiment does not limit them.

[0093] It should also be noted that the aforementioned current partition surface temperature can be the current surface temperature of the corresponding partition on the liquid crystal lens after the region division. To obtain the surface temperature of each current partition, this embodiment can set multiple first temperature acquisition components, such as eight, when installing the aforementioned first temperature acquisition components. These components are evenly distributed to ensure coverage of the center and edges of the liquid crystal lens, thereby acquiring the surface temperature of each preset lens partition and thus collecting the surface temperature at each location of the liquid crystal lens. The specific placement can be set according to actual conditions, and this embodiment does not impose any limitations on this.

[0094] In practical use, the smart glasses can obtain the target refractive index and, at the same time, obtain the current surface temperature of each preset lens zone through the aforementioned first temperature acquisition component.

[0095] Accordingly, the step of obtaining the target lens driving voltage by querying a preset mapping table based on the target refractive index and the current lens surface temperature includes:

[0096] Step S21: Determine whether there is a temperature difference higher than a preset temperature difference threshold among the current temperature differences between the surface temperatures of each current partition.

[0097] It is understood that the aforementioned current temperature difference can be the temperature difference between any two of the current surface temperatures of each preset lens partition. The aforementioned preset temperature difference threshold can be a threshold used to characterize a large current temperature difference; in this embodiment, the aforementioned current temperature difference can be denoted as... T, the above-mentioned preset temperature difference threshold can be described using 3℃.

[0098] Considering that if the temperature difference between each preset lens partition is small, there is no need for differentiated driving, thereby improving the response speed, in this embodiment, after obtaining the current surface temperature of each preset lens partition, the temperature difference between each pair of current partition surfaces can be calculated to obtain the corresponding current temperature difference. T, then it can be determined whether the current temperature difference exists in the current temperature difference. The current zone surface temperature is T > 3℃.

[0099] Step S22: If none of the current temperature differences are higher than the preset temperature difference threshold, determine the current lens surface temperature based on the surface temperature of each current partition;

[0100] Step S23: Query the preset mapping relationship table according to the target refractive index and the current lens surface temperature to obtain the target lens driving voltage.

[0101] If it does not exist, it means that the surface temperature difference between each preset lens partition is small. In this case, the average surface temperature can be obtained by directly calculating the average surface temperature of each current partition. This average surface temperature is then used as the current lens surface temperature. The target lens driving voltage is obtained by querying the preset mapping relationship in conjunction with the target refractive index. The target lens driving voltage is then output for each preset lens partition to drive it.

[0102] Furthermore, if a temperature difference exceeding a preset threshold exists, in this embodiment, after the step of determining whether any current temperature difference between the surface temperatures of each current partition exceeds the preset temperature difference threshold, the method further includes:

[0103] Step S24: If any of the current temperature differences is higher than the preset temperature difference threshold, query the preset mapping relationship table according to the target refractive index and the surface temperature of each current partition to obtain the target partition driving voltage corresponding to each preset lens partition;

[0104] Accordingly, the step of driving the liquid crystal lens according to the target lens driving voltage includes:

[0105] Step S31: Drive the corresponding preset lens partition according to the target partition driving voltage.

[0106] It should be understood that the aforementioned target partition driving voltage can be a driving voltage used to drive a preset lens partition.

[0107] In practical use, it is necessary to determine whether the current temperature difference exists within the current temperature range. If the current partition surface temperature T > 3℃ exists, it indicates that there are lens partitions with large surface temperature differences among the lens partitions. Therefore, differentiated driving can be adopted. Specifically, the preset mapping relationship can be queried according to the target refractive index and the current partition surface temperature corresponding to each preset lens partition to obtain the driving voltage corresponding to each preset lens partition, which is used as the driving voltage of the target partition.

[0108] After obtaining the target partition driving voltage for each preset lens partition, the corresponding target partition driving voltage can be output to each preset lens partition. In this embodiment, a wide temperature range driving circuit can also be provided in the smart glasses. The corresponding target partition driving voltage can be output to each preset lens partition through the wide temperature range driving circuit, so that the liquid crystal lens can achieve the target refractive index.

[0109] Reference Figure 4 , Figure 4 This is a flowchart illustrating the third embodiment of the refractive index adjustment method of this application. Based on the above embodiments, a third embodiment of the refractive index adjustment method of this application is proposed.

[0110] To improve the accuracy of temperature determination and reduce response time, such as Figure 4 As shown, in this embodiment, the step of determining whether there is a current temperature difference higher than a preset temperature difference threshold among the current temperature differences between the surface temperatures of each current partition includes:

[0111] Step S211: Obtain the current ambient temperature of the smart glasses.

[0112] It should be noted that the aforementioned current ambient temperature can be the current temperature of the environment in which the smart glasses are located. In this embodiment, a second temperature acquisition component can be provided on the smart glasses. This second temperature acquisition component can be any component used to acquire ambient temperature. In this embodiment, an ambient temperature probe can be used (the measuring range can be -30℃ to 60℃). Furthermore, in this embodiment, the aforementioned second temperature acquisition component can be placed at any convenient location on the smart glasses for acquiring ambient temperature, such as the temples, etc. This embodiment does not impose any restrictions on this.

[0113] Step S212: Using a Kalman filter, predict the predicted surface temperature of each preset lens partition based on the current ambient temperature and the surface temperature of each current partition.

[0114] It should also be noted that the predicted surface temperature of the aforementioned zones can be the surface temperature corresponding to each preset lens zone after prediction by a Kalman filter. In this embodiment, the Kalman filter can obtain more comprehensive and accurate temperature distribution information by fusing limited measurement data and system models. Specifically, it can predict the current zone surface temperature of each lens zone at the next moment based on the current ambient temperature at the previous moment and the current zone surface temperature at the previous moment.

[0115] When using a Kalman filter for prediction, the state vector can be defined first. , representing the surface temperature of each preset lens partition of the liquid crystal lens at time k. For example, for 36 partitions, the state vector can be:

[0116]

[0117] in, This represents the surface temperature of the i-th preset lens partition at time k.

[0118] Next, a state transition model is defined to describe the propagation and change of temperature between adjacent preset lens zones. For example, assuming that the temperature change follows a first-order linear system, the state transition model can be expressed as:

[0119]

[0120] in, This is the state transition matrix, which can be used to describe the relationship between temperature and time. The input matrix can be used to describe the effect of ambient temperature on the lens surface temperature. It can be an ambient temperature input vector. It can be process noise, assumed to be Gaussian white noise with a mean of 0 and a covariance matrix of Q.

[0121] Then, an observation model can be defined to describe the relationship between the observed data and the true state. For example, the observation model can be represented as:

[0122] ;

[0123] in, It can be an observation vector, which can include the current lens surface temperature and the current ambient temperature. It can be an observation matrix. It can be observation noise, assumed to be Gaussian white noise with a mean of 0 and a covariance matrix of R.

[0124] Based on the above definition, filtering is then performed using a Kalman filter. Firstly, during the prediction phase, an initializable state vector is obtained. Covariance Matrix Predicted state vector: Predict the covariance matrix: ;in To predict the state vector, To predict the covariance matrix.

[0125] The Kalman gain can be calculated during the update phase: Update the state vector: Update the covariance matrix: ;in For the transpose of the observation matrix, For Kalman gain, This is the updated covariance matrix.

[0126] Therefore, in this embodiment, the prediction stage and update stage can be repeated every sampling period to continuously predict and obtain the predicted zone surface temperature corresponding to each preset lens zone.

[0127] Step S213: Determine whether there is a predicted temperature difference higher than a preset temperature difference threshold among the predicted temperature differences between the surface temperatures of each predicted partition.

[0128] After the surface temperature of each predicted zone is obtained, the difference between each predicted zone surface temperature can be calculated as the predicted temperature difference, and then the predicted temperature difference can be used as the current temperature difference to determine whether it is higher than the preset temperature difference threshold.

[0129] Furthermore, considering the need to improve response speed when driving the liquid crystal lens, in this embodiment, after obtaining the current ambient temperature of the smart glasses, the method further includes:

[0130] Step S2111: When the current ambient temperature is lower than the preset normal temperature, the initial lens driving voltage of the liquid crystal lens is obtained by querying the initial mapping relationship table according to the preset normal temperature and the target refractive index. The initial mapping relationship table is a mapping relationship table between different normal lens driving voltages and corresponding normal refractive indices at the preset normal temperature.

[0131] It should be noted that the preset normal temperature mentioned above can be the temperature when the liquid crystal lens does not experience driving voltage mismatch, that is, in this embodiment, the preset normal temperature mentioned above can be 20°C.

[0132] It should also be noted that the above initial mapping table can be a mapping table between different normal lens driving voltages and corresponding normal refractive indices for a liquid crystal lens at this preset normal temperature. The normal lens driving voltage can be the driving voltage required to achieve the normal refractive index at 20℃.

[0133] In this embodiment, the smart glasses can still be placed in a constant temperature chamber and the chamber can be controlled at 20°C. Then, different driving voltages can be output to the liquid crystal lens to make it reach the corresponding refractive index and the result is recorded. Based on the recorded result, the above-mentioned initial mapping relationship table can be obtained.

[0134] In practical use, after the smart glasses determine the current ambient temperature, they can first determine whether the current ambient temperature is lower than 20°C. If it is not lower than 20°C, the Kalman filter can be used to make predictions and execute the subsequent steps mentioned above. This embodiment will not elaborate on this.

[0135] If the temperature is below 20°C, the initial mapping table above can be consulted based on 20°C and the target refractive index to obtain the driving voltage required to achieve the target refractive index at 20°C. This driving voltage can be used as the initial lens driving voltage. For ease of subsequent explanation, this initial lens driving voltage can be denoted as... .

[0136] Step S2112: Determine the reference driving voltage based on the current ambient temperature, the preset normal temperature, and the initial lens driving voltage.

[0137] It is understood that the aforementioned reference driving voltage can be a reference voltage value for driving the liquid crystal lens in a low-temperature environment. For ease of subsequent explanation, this reference driving voltage can be denoted as... The current ambient temperature is denoted as T_env.

[0138] In this embodiment, the aforementioned reference driving voltage can be obtained through a preset reference voltage determination formula, which is as follows:

[0139]

[0140] 20 represents the preset normal temperature; a is a temperature coefficient, which represents the adjustment ratio of the base voltage to each degree Celsius temperature change. This temperature coefficient can be set according to the actual situation. This embodiment does not limit this setting. For example, 0.015 can be used.

[0141] In practical use, when the smart glasses determine that the current ambient temperature is below 20℃, the initial lens driving voltage is obtained by looking up the table as described above. Then, the initial lens driving voltage can be substituted into the above-mentioned preset reference voltage determination formula to obtain the reference driving voltage. Then, the reference driving voltage can be used as a guide. Drive the liquid crystal lens to make the refraction of the liquid crystal lens initially adjusted.

[0142] To ensure a more accurate refractive index, after initial adjustment, the step of driving the liquid crystal lens according to the target lens driving voltage includes:

[0143] Step S311: Determine the driving compensation voltage based on the reference driving voltage and the target lens driving voltage, compensate the reference driving voltage with the driving compensation voltage, and drive the liquid crystal lens according to the compensated reference driving voltage.

[0144] It should be understood that the aforementioned driving compensation voltage can be a voltage used to compensate the voltage driven to the liquid crystal lens from the reference driving voltage to the target lens driving voltage, or it can be understood as the difference between the target lens driving voltage and the reference driving voltage.

[0145] In practical use, after the liquid crystal lens is initially adjusted, the smart glasses can determine the target lens driving voltage corresponding to each preset lens partition according to the above steps (if lens partitioning is performed, the target partition driving voltage can be determined). Then, the difference between the target lens driving voltage and the reference driving voltage is used as the driving compensation voltage. The reference driving voltage is compensated by the driving compensation voltage, and the compensated reference driving voltage is output, so that the refractive index of the liquid crystal lens reaches the target refractive index.

[0146] Furthermore, considering that low temperatures may increase the response time of liquid crystal molecules within the liquid crystal lens, in order to reduce the response time, in this embodiment, after obtaining the current ambient temperature of the smart glasses, the method further includes:

[0147] Step S2113: When the current ambient temperature is lower than the preset normal temperature, obtain the initial driving frequency corresponding to the preset normal temperature.

[0148] It should be noted that the aforementioned initial driving frequency can be the frequency at which the smart glasses output the driving voltage at 20°C. This initial driving frequency can be preset according to actual conditions, and this embodiment does not impose any restrictions on it. For ease of subsequent explanation, this embodiment will refer to the aforementioned initial driving frequency as... .

[0149] Accordingly, the step of driving the liquid crystal lens according to the target lens driving voltage includes:

[0150] Step S312: Determine the target driving frequency based on the current ambient temperature, the preset normal temperature, and the initial driving frequency, and drive the liquid crystal lens using the target driving frequency according to the target lens driving voltage.

[0151] It is understood that the target driving frequency mentioned above can be the frequency of the output driving voltage in a low-temperature environment. For ease of explanation later, the target driving frequency is denoted as f(T).

[0152] In this embodiment, the target driving frequency can be obtained by a preset frequency determination formula, which is:

[0153]

[0154] 20 represents the preset normal temperature; b is the frequency coefficient, which represents the adjustment ratio of the driving frequency to each degree Celsius temperature change. This frequency coefficient can be set according to the actual situation. This embodiment does not limit this setting. For example, 0.02 can be used.

[0155] In practical use, when the smart glasses determine that the current ambient temperature is below 20℃, they obtain the corresponding initial driving frequency. Then, the initial driving frequency can be substituted into the above preset frequency determination formula to obtain the target driving frequency. Then, the target driving frequency can be used. The target lens driving voltage is output, thereby reducing the response time of the liquid crystal molecules.

[0156] Furthermore, embodiments of this application also propose a storage medium storing a refractive index adjustment program, which, when executed by a processor, implements the steps of the refractive index adjustment method described above.

[0157] In addition, refer to Figure 5 , Figure 5 This is a structural block diagram of the first embodiment of the refractive index adjustment device of this application; as shown Figure 5 As shown in the embodiments of this application, a refractive index adjustment device is also proposed, which includes:

[0158] The parameter acquisition module 501 is used to acquire the current lens surface temperature and target refractive index of the liquid crystal lens;

[0159] The voltage query module 502 is used to query a preset mapping relationship table based on the target refractive index and the current lens surface temperature to obtain the target lens driving voltage. The preset mapping relationship table is a mapping relationship table between different test lens driving voltages and corresponding test refractive indices at different test lens surface temperatures.

[0160] The lens driving module 503 is used to drive the liquid crystal lens according to the target lens driving voltage, so as to adjust the refractive index of the liquid crystal lens to the target refractive index.

[0161] In this embodiment, a preset mapping table can be pre-constructed between different test lens driving voltages and corresponding test refractive indices at different test lens surface temperatures. In actual use, the current lens surface temperature and target refractive index of the liquid crystal lens can be obtained first. Based on the target refractive index and the current lens surface temperature, the preset mapping table is consulted to obtain the target lens driving voltage. Then, the liquid crystal lens can be driven according to this target lens driving voltage, thereby achieving the target refractive index. Compared to existing methods that require heating the liquid crystal lens to a normal temperature using a heating film at low temperatures, and then determining the corresponding driving voltage based on the target refractive index at normal temperature, this embodiment allows for setting the mapping relationship between different test driving voltages and test refractive indices at different current lens surface temperatures. Therefore, in actual use, the preset mapping relationship can be directly consulted for refractive index adjustment, eliminating the need for a heating film and thus improving the thinness and lightness of the smart glasses.

[0162] In one implementation, the parameter acquisition module 501 is further configured to heat the liquid crystal lens according to a preset temperature step, and drive the liquid crystal lens at the surface temperature of each test lens so that the refractive index of the liquid crystal lens reaches the test refractive index; obtain the test lens driving voltage according to the driving result, and construct a mapping relationship table according to the test lens driving voltage, the test lens surface temperature and the test refractive index.

[0163] Based on the first embodiment of the refractive index adjustment device described above, a second embodiment of the refractive index adjustment device of this application is proposed.

[0164] In this embodiment, the liquid crystal lens is divided according to a preset lens partition, and the parameter acquisition module 501 is also used to acquire the current partition surface temperature of each preset lens partition in the liquid crystal lens;

[0165] The voltage query module 502 is further configured to determine whether any of the current temperature differences between the surface temperatures of each current partition are higher than a preset temperature difference threshold; if none of the current temperature differences are higher than the preset temperature difference threshold, the current lens surface temperature is determined based on the surface temperatures of each current partition; and the target lens driving voltage is obtained by querying a preset mapping relationship table according to the target refractive index and the current lens surface temperature.

[0166] As one implementation, the voltage query module 502 is also used to query a preset mapping relationship table based on the target refractive index and the surface temperature of each current zone when there is a temperature difference higher than the preset temperature difference threshold, in order to obtain the target zone driving voltage corresponding to each preset lens zone.

[0167] The lens driving module 503 is also used to drive the corresponding preset lens partition according to the driving voltage of each target partition.

[0168] Based on the above embodiments of the refractive index adjustment device of this application, a third embodiment of the refractive index adjustment device of this application is proposed.

[0169] In this embodiment, the voltage query module 502 is further used to obtain the current ambient temperature of the smart glasses; to use a Kalman filter to predict the predicted surface temperature of each preset lens partition based on the current ambient temperature and the surface temperature of each current partition; and to determine whether there is a predicted temperature difference between the predicted surface temperatures of each predicted partition that is higher than a preset temperature difference threshold.

[0170] In one implementation, the parameter acquisition module 501 is further configured to, when the current ambient temperature is lower than a preset normal temperature, query an initial mapping table based on the preset normal temperature and the target refractive index to obtain the initial lens driving voltage of the liquid crystal lens. The initial mapping table is a mapping table between different normal lens driving voltages and corresponding normal refractive indices at the preset normal temperature. A reference driving voltage is determined based on the current ambient temperature, the preset normal temperature, and the initial lens driving voltage.

[0171] The lens driving module 503 is further configured to determine a driving compensation voltage based on the reference driving voltage and the target lens driving voltage, compensate the reference driving voltage with the driving compensation voltage, and drive the liquid crystal lens according to the compensated reference driving voltage.

[0172] As one implementation, the parameter acquisition module 501 is also used to acquire the initial driving frequency corresponding to the preset normal temperature when the current ambient temperature is lower than the preset normal temperature.

[0173] The lens driving module 503 is further configured to determine a target driving frequency based on the current ambient temperature, the preset normal temperature and the initial driving frequency, and drive the liquid crystal lens according to the target lens driving voltage using the target driving frequency.

[0174] Other embodiments or specific implementations of the refractive index adjustment device described in this application can be found in the above-described method embodiments, and will not be repeated here.

[0175] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0176] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0177] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as a read-only memory image (ROM) / random access memory (RAM), magnetic disk, optical disk), and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0178] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A method of refractive index adjustment, characterized by, The method is applied to smart glasses provided with a liquid crystal lens, and the method comprises the following steps: obtaining a current lens surface temperature of the liquid crystal lens and a target refractive index, the target refractive index being a refractive index for the user to clearly observe an image, the target refractive index being set by the user in advance; querying a preset mapping relationship table according to the target refractive index and the current lens surface temperature to obtain a target lens driving voltage, the preset mapping relationship table being a mapping relationship table between different test lens driving voltages and corresponding test refractive indices under different test lens surface temperatures; driving the liquid crystal lens according to the target lens driving voltage to adjust the refractive index of the liquid crystal lens to the target refractive index; the liquid crystal lens is divided into preset lens partitions; the step of obtaining the current lens surface temperature of the liquid crystal lens comprises the following steps: obtaining a current partition surface temperature of each lens partition in the liquid crystal lens; the step of querying the preset mapping relationship table according to the target refractive index and the current lens surface temperature to obtain the target lens driving voltage comprises the following steps: determining the current lens surface temperature based on the current partition surface temperature of each lens partition in the case that there is no current temperature difference higher than a preset temperature difference threshold in the current temperature difference between the current partition surface temperatures; and querying the preset mapping relationship table according to the target refractive index and the current lens surface temperature to obtain the target lens driving voltage.

2. The method of claim 1, wherein, before the step of obtaining the current lens surface temperature of the liquid crystal lens and the target refractive index, the method further comprises the following steps: warming up the liquid crystal lens according to a preset temperature step, and driving the liquid crystal lens at each test lens surface temperature to make the refractive index of the liquid crystal lens reach a test refractive index; obtaining a test lens driving voltage according to a driving result, and constructing a mapping relationship table according to the test lens driving voltage, the test lens surface temperature and the test refractive index.

3. The method of claim 1, wherein, after the step of determining whether there is a current temperature difference higher than a preset temperature difference threshold in the current temperature difference between the current partition surface temperatures, the method further comprises the following steps: in the case that there is a current temperature difference higher than the preset temperature difference threshold in the current temperature difference between the current partition surface temperatures, querying the preset mapping relationship table according to the target refractive index and the current partition surface temperature of each lens partition to obtain a target partition driving voltage corresponding to each preset lens partition; the step of driving the liquid crystal lens according to the target lens driving voltage comprises the following step: driving each preset lens partition according to the target partition driving voltage.

4. The method of claim 1, wherein, the step of determining whether there is a current temperature difference higher than a preset temperature difference threshold in the current temperature difference between the current partition surface temperatures comprises the following steps: obtaining a current environment temperature of the smart glasses; obtaining a predicted partition surface temperature corresponding to each preset lens partition by using a Kalman filter to predict according to the current environment temperature and the current partition surface temperature of each lens partition; and determining whether a predicted temperature difference between the predicted surface temperatures of the prediction partitions is higher than a preset temperature difference threshold.

5. The method of claim 4, wherein, The obtaining of the current ambient temperature of the smart glasses further includes: In a case where the current ambient temperature is lower than a preset normal temperature, an initial lens driving voltage of the liquid crystal lens is obtained according to the preset normal temperature and the target refractive index, the initial mapping relationship table being a mapping relationship table between different normal lens driving voltages and corresponding normal refractive indices at the preset normal temperature; a reference driving voltage is determined based on the current ambient temperature, the preset normal temperature and the initial lens driving voltage; The step of driving the liquid crystal lens according to the target lens driving voltage includes: a driving compensation voltage is determined according to the reference driving voltage and the target lens driving voltage, the reference driving voltage is compensated by the driving compensation voltage, and the liquid crystal lens is driven according to the compensated reference driving voltage.

6. The method of claim 4, wherein, The obtaining of the current ambient temperature of the smart glasses further includes: In a case where the current ambient temperature is lower than a preset normal temperature, an initial driving frequency corresponding to the preset normal temperature is obtained; The step of driving the liquid crystal lens according to the target lens driving voltage includes: a target driving frequency is determined based on the current ambient temperature, the preset normal temperature and the initial driving frequency, and the liquid crystal lens is driven according to the target lens driving voltage by using the target driving frequency.

7. A refractive index adjusting device characterized by comprising: The device includes: A parameter acquisition module is configured to acquire a current lens surface temperature of a liquid crystal lens and a target refractive index, the target refractive index being a refractive index for a user to clearly observe an image, and the target refractive index being set by the user in advance. A voltage query module is configured to query a preset mapping relationship table according to the target refractive index and the current lens surface temperature to obtain a target lens driving voltage, the preset mapping relationship table being a mapping relationship table between different test lens driving voltages and corresponding test refractive indices at different test lens surface temperatures. A lens driving module is configured to drive the liquid crystal lens according to the target lens driving voltage, so that the refractive index of the liquid crystal lens is adjusted to the target refractive index. The liquid crystal lens is divided into preset lens partitions. The parameter acquisition module is further configured to acquire a current partition surface temperature of each of the preset lens partitions in the liquid crystal lens. The voltage query module is further configured to determine whether a current temperature difference between the current partition surface temperatures is higher than a preset temperature difference threshold, the current temperature difference being a temperature difference between each of the current partition surface temperatures; in a case where the current temperature difference is not higher than the preset temperature difference threshold, the current lens surface temperature is determined based on the current partition surface temperatures; and a target lens driving voltage is obtained by querying a preset mapping relationship table according to the target refractive index and the current lens surface temperature.

8. An intelligent eyewear, characterized in that, The smart glasses comprise a liquid crystal lens, a memory, a processor, and a refractive index adjustment program stored on the memory and executable on the processor, the refractive index adjustment program, when executed by the processor, implements the steps of the refractive index adjustment method according to any one of claims 1 to 6.

9. A storage medium, characterized by The storage medium stores a refractive index adjustment program, the refractive index adjustment program, when executed by the processor, implements the steps of the refractive index adjustment method according to any one of claims 1 to 6.

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