Focus synchronization method and device for multi-camera module application and electronic equipment

Abstract

The application discloses a focusing synchronization method and device applied to a multi-camera module and electronic equipment. The method comprises the following steps: determining two target camera modules that are lighted; obtaining the focal length parameters of the two target camera modules; determining the focal length overlap range, the preset near focus ratio and the preset hyperfocal distance ratio according to the focal length parameters of the two target camera modules; and controlling the two target camera modules to perform focusing synchronization according to the focal length overlap range, the preset near focus ratio and the preset hyperfocal distance ratio of the two target camera modules. In this way, when a mobile phone has multiple camera modules, the precise focusing synchronization of the two target camera modules can be realized, and the correction result can be corrected according to the correction Dac value.

Description

Technical Field

[0001] This invention relates to the field of camera technology, and in particular to a focusing synchronization method, apparatus, and electronic device for multi-camera module applications. Background Technology

[0002] With the development of smartphones, the number of camera modules on mobile phones has also increased. Current ordinary mobile phones generally have two camera modules. Flagship phones typically have three camera modules. As technology advances, the number of camera modules on mobile phones is likely to continue to increase.

[0003] When taking photos, the two camera modules typically autofocus independently to ensure a clear image on the film. However, as the number of camera modules on a mobile phone increases, the focus synchronization mechanism becomes more complex.

[0004] Therefore, a focus synchronization method is needed that can still switch between any two camera modules for focus synchronization even when a mobile phone has more and more camera modules. Summary of the Invention

[0005] In view of the above problems, the present invention is proposed to provide a focusing synchronization method, apparatus and electronic device for multi-camera module applications.

[0006] According to a first aspect of the present invention, a focus synchronization method for a multi-camera module application is provided, comprising:

[0007] Identify the two target camera modules that have been illuminated;

[0008] Obtain the focal length parameters of the two target camera modules respectively;

[0009] Based on the focal length parameters of the two target camera modules, the focal length overlap range, the preset near-focus ratio, and the preset hyperfocal distance ratio are determined.

[0010] Based on the focal length overlap range, preset near-focus ratio, and preset hyperfocal distance ratio of the two target camera modules, the two target camera modules are controlled to synchronize focus.

[0011] Optional focal length parameters include near focal length and hyperfocal length;

[0012] Based on the focal length parameters of the two target camera modules, the focal length overlap range is determined, including:

[0013] Select the maximum near focal length from the two target camera modules;

[0014] The maximum hyperfocal distance is selected from the hyperfocal distances of the two target camera modules; the range between the maximum near focal distance and the maximum hyperfocal distance constitutes the focal length overlap range.

[0015] Optionally, based on the focal length overlap range, preset near-focus ratio, and preset hyperfocal distance ratio of the two target camera modules, control the two target camera modules to synchronize focus, including:

[0016] Based on the focal overlap range, preset near-focus ratio, and preset hyperfocal distance ratio of the two target camera modules, the Dac values ​​of the input motor drive chips corresponding to the focal overlap range of the two target camera modules are calculated respectively.

[0017] Based on the DAC value of their respective input motor driver chips, the two target camera modules are controlled to synchronize focus.

[0018] Optionally, based on the focal length overlap range, preset near-focus ratio, and preset hyperfocal distance ratio of the two target camera modules, the Dac values ​​of the input motor drive chips corresponding to the focal length overlap range of the two target camera modules are calculated, including:

[0019] Based on the focal length overlap range, the first camera module and the preset close-focus ratio are determined from the two target camera modules. The preset close-focus ratio is the close-focus ratio coefficient of the first camera module relative to the other target camera module, and it is obtained in advance.

[0020] Based on the pre-recorded near focal length Dac, hyperfocal length Dac values ​​of the first camera module and the preset near focal length ratio, the near focal length Dac value corresponding to the focal length overlap range of the first camera module is obtained.

[0021] Based on the focal length overlap range, the second camera module and the preset hyperfocal distance ratio are determined from the two target camera modules. The preset hyperfocal distance ratio is the hyperfocal distance ratio coefficient of the second camera module relative to the other target, and it is obtained in advance.

[0022] Based on the pre-recorded near-focal distance Dac value, hyperfocal distance Dac value, and preset hyperfocal distance ratio of the second camera module, the hyperfocal distance Dac value corresponding to the focal length overlap range of the second camera module is obtained.

[0023] Optionally, based on the focal length overlap range, a first camera module and a preset close-focus ratio are determined from the two target camera modules, including:

[0024] From the two target camera modules, the target camera module with the smaller near focal length is selected as the first camera module;

[0025] Obtain the preset near-focus ratio of the first target camera module relative to another target camera module.

[0026] Optionally, based on the focal length overlap range, a second camera module and a preset hyperfocal length ratio are determined from the two target camera modules, including:

[0027] From the two target camera modules, the target camera module with the smaller hyperfocal distance is selected as the second camera module;

[0028] Obtain the preset hyperfocal distance ratio of the second target camera module relative to another target camera module.

[0029] Optionally, the method also includes:

[0030] Determine whether the Dac value is within ±25% of the preset correction Dac value;

[0031] If they are present, the two target camera modules will successfully synchronize their focus; otherwise, the two target camera modules will fail to synchronize their focus.

[0032] According to a second aspect of the present invention, a focus synchronization device for multi-camera module applications is provided, comprising:

[0033] The camera illumination module is used to identify the two target camera modules that are illuminated.

[0034] The data acquisition module is used to acquire the focal length parameters of the two target camera modules respectively;

[0035] The calculation and processing module is used to determine the focal length overlap range, preset near-focus ratio, and preset hyperfocal distance ratio based on the focal length parameters of the two target camera modules.

[0036] The focus synchronization module is used to control the two target camera modules to synchronize focus based on the focal length overlap range, preset near-focus ratio, and preset hyperfocal distance ratio of the two target camera modules.

[0037] According to a third aspect of the present invention, an electronic device is provided, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the aforementioned focus synchronization method for a multi-camera module application.

[0038] According to a fourth aspect of the present invention, a computer-readable storage medium is provided having a computer program stored thereon that, when executed by a processor, implements the aforementioned focus synchronization method for a multi-camera module application.

[0039] The above-described one or more technical solutions in the embodiments of this specification have at least the following technical effects:

[0040] This specification provides a focus synchronization method, apparatus, and electronic device for multi-camera module applications. The method involves identifying two target camera modules to be illuminated; then acquiring the focal length parameters of each target camera module; subsequently determining the focal length overlap range, a preset near-focus ratio, and a preset hyperfocal distance ratio based on these parameters; and finally controlling the two target camera modules to synchronize focus based on these parameters. Thus, when a mobile phone has multiple camera modules, precise focus synchronization between two target camera modules can be achieved, and the calibration result can be corrected based on the calibration DAC value.

[0041] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0042] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference figures denote the same parts throughout the drawings.

[0043] In the attached diagram:

[0044] Figure 1 A schematic diagram of an electronic device according to an embodiment of the present invention is shown.

[0045] Figure 2 A flowchart of a focus synchronization method for a multi-camera module application in an embodiment of the present invention is shown.

[0046] Figure 3 A schematic diagram of a multi-camera module according to an embodiment of the present invention is shown.

[0047] Figure 4 A graph showing the relationship between the Dac value and the image distance in an embodiment of the present invention is provided.

[0048] Figure 5 A block diagram of a focus synchronization device for a multi-camera module application is shown in an embodiment of the present invention.

[0049] icon:

[0050] 100 - Electronic equipment; 10 - Focusing synchronization device for multi-camera module applications; 11 - Camera lighting module; 12 - Data acquisition module; 13 - Calculation and processing module; 14 - Focusing synchronization module; 20 - Memory; 30 - Processor; 40 - Communication unit. Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0052] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0053] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0054] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0055] Please see Figure 1 , Figure 1 This is a structural block diagram of an electronic device 100 provided in this embodiment. Figure 1 As shown, the electronic device may include a focus synchronization device 10 for multi-camera module applications, a memory 20, a processor 30, and a communication unit 40. The memory 20 stores machine-readable instructions that can be executed by the processor 30. When the electronic device 100 is running, the processor 30 and the memory 20 communicate with each other via a bus. The processor 30 executes the machine-readable instructions and performs the focus synchronization method for multi-camera module applications.

[0056] The memory 20, processor 30, and communication unit 40 are electrically connected directly or indirectly to each other to achieve signal transmission or interaction. For example, these components can be electrically connected to each other through one or more communication buses or signal lines. The focus synchronization device 10 for multi-camera module applications includes at least one software function module that can be stored in the memory 20 in the form of software or firmware. The processor 30 is used to execute the executable module stored in the memory 20 (e.g., the software function module or computer program included in the focus synchronization device 10 for multi-camera module applications).

[0057] The memory 20 may be, but is not limited to, random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), etc.

[0058] In some embodiments, processor 30 is used to perform one or more functions described in this embodiment. In some embodiments, processor 30 may include one or more processing cores (e.g., a single-core processor (S) or a multi-core processor (S)). By way of example only, processor 30 may include a central processing unit (CPU), an application-specific integrated circuit (ASIC), an application-specific instruction-set processor (ASICP), a graphics processing unit (GPU), a physical processing unit (PPU), a digital signal processor (DSP), a field-programmable gate array (FPGA), a programmable logic device (PLD), a controller, a microcontroller unit, a reduced instruction set computer (RISC), or a microprocessor, or any combination thereof.

[0059] For ease of explanation, only one processor is described in electronic device 100. However, it should be noted that electronic device 100 in this embodiment may also include multiple processors, and therefore the steps performed by one processor as described in this embodiment may also be performed jointly or individually by multiple processors. For example, if the server's processor performs steps A and B, it should be understood that steps A and B may also be performed jointly by two different processors or individually by one processor. For example, one processor performs step A, and a second processor performs step B, or the first and second processors jointly perform steps A and B.

[0060] In this embodiment, the memory 20 is used to store the program, and the processor 30 is used to execute the program after receiving the execution instruction. The process definition method disclosed in any implementation of this embodiment can be applied to the processor 30, or implemented by the processor 30.

[0061] The communication unit 40 is used to establish a communication connection between the electronic device 100 and other devices via a network, and to send and receive data via the network.

[0062] In some implementations, the network can be any type of wired or wireless network, or a combination thereof. By way of example only, the network may include wired networks, wireless networks, fiber optic networks, telecommunications networks, intranets, the Internet, local area networks (LANs), wide area networks (WANs), wireless local area networks (WLANs), metropolitan area networks (MANs), public switched telephone networks (PSTNs), Bluetooth networks, ZigBee networks, or near field communication (NFC) networks, or any combination thereof.

[0063] In this embodiment, the electronic device 100 may be, but is not limited to, smartphones, tablets, personal digital assistants (PDAs), etc. This embodiment does not impose any restrictions on the specific type of electronic device, but the electronic device in this embodiment has multiple camera modules for taking pictures.

[0064] Understandably, Figure 1 The structure shown is for illustrative purposes only. The electronic device 100 may also have... Figure 1 Showing more or fewer components, or having with Figure 1 The different configurations shown. Figure 1 The components shown can be implemented using hardware, software, or a combination thereof.

[0065] based on Figure 1 The implementation architecture of this embodiment provides a focus synchronization method for multi-camera module applications, which is based on... Figure 1 The electronic device 100 shown performs the following based on Figure 1 The structural diagram of the electronic device 100 shown illustrates in detail the steps of the focus synchronization method for the multi-camera module application provided in this embodiment, in conjunction with... Figure 2 As shown, the focus synchronization method used in this multi-camera module includes steps 101 to 104:

[0066] Step 101: Identify the two target camera modules that are illuminated.

[0067] In this embodiment, the electronic device 100 is described using a mobile phone as an example, in conjunction with... Figure 3As shown, this phone has three camera modules: an ultra-wide-angle camera module (Ultra Wide), a standard wide-angle camera module (Wide), and a periscope camera module (Tele). The ultra-wide-angle camera module has a focus range of 5cm to infinity and a hyperfocal distance of 30cm. The standard wide-angle camera module has a focus range of 10cm to infinity and a hyperfocal distance of 500cm. The periscope camera module has a focus range of 30cm to infinity and a hyperfocal distance of 900cm. These are the parameters of the camera modules.

[0068] When a mobile phone takes a picture, two camera modules are usually illuminated. The illuminated camera module is designated as the target camera module. For example, when taking a picture, the wide-angle camera module and the periscope camera module are usually illuminated, and these two modules are considered the target camera modules. The mobile phone can determine which camera module is illuminated by identifying its field of view. Generally, the field of view of an ultra-wide-angle camera module is greater than 100 degrees, the field of view of a typical wide-angle camera module is 70-85 degrees, and the field of view of a periscope camera module is 55-70 degrees.

[0069] Step 102: Obtain the focal length parameters of the two target camera modules respectively;

[0070] After identifying the two target camera modules to be illuminated, their focal length parameters can be obtained. It should be noted that in this embodiment, the focal length parameters mainly include near-focal distance and hyperfocal distance, where near-focal distance refers to the closest focal length within the focusing range. For example, if an ultra-wide-angle camera module has a focusing range of 5cm to infinity and a hyperfocal distance of 30cm, then the focal length parameters of this target camera module are a near-focal distance of 5cm and a hyperfocal distance of 30cm.

[0071] Step 103: Based on the focal length parameters of the two target camera modules, determine the focal length overlap range, the preset near-focus ratio, and the preset hyperfocal distance ratio;

[0072] For the two illuminated target camera modules to achieve focus synchronization, their focal length overlap range must first be determined. The focal length overlap range refers to the focus range within which both target camera modules can achieve a clear image. For example, combining... Figure 3 As shown, the focal length overlap range between the ultra-wide-angle camera module and the wide-angle camera module is 10cm-500cm; the focal length overlap range between the wide-angle camera module and the periscope camera module is 30cm-900cm.

[0073] In other words, the larger near focal length is selected from the near focal length values ​​of the two target camera modules; the larger hyperfocal length is selected from the hyperfocal lengths of the two target camera modules; and the range between the larger near focal length and the larger hyperfocal length constitutes the focal length overlap range.

[0074] It should be noted that if the near-focal distance values ​​of the two target camera modules are equal, either one will be selected. Similarly, if the hyperfocal distances of the two target camera modules are equal, either one will be selected. Of course, this situation rarely occurs.

[0075] It should be explained that the preset close-focus ratio and preset hyperfocal distance ratio are preset and stored on the mobile phone. For each target camera module, there may be multiple preset close-focus ratios and preset hyperfocal distance ratios, or none at all.

[0076] Specifically, the number of camera modules in the mobile phone is fixed and known. For example, the mobile phone in this embodiment has three camera modules. The parameters of these camera modules are also known. Based on this, all possible combinations of the illuminated target camera modules can be listed. Therefore, for any combination, their focal length overlap range can be determined. For focus synchronization, the two target camera modules need to be determined, where the near-focal distance (DAC) value and the hyperfocal distance (DAC) value correspond to the near-focal distance and hyperfocal distance within the focal length overlap range.

[0077] It's important to explain that the DAC values ​​corresponding to the near-focal distance and hyperfocal distance of each target camera module are pre-measured and programmed. When combined with other target camera modules, due to focus synchronization requirements, additional near-focal distance and hyperfocal distance DAC values ​​corresponding to the overlapping focal length range may be needed. These near-focal distance and hyperfocal distance DAC values ​​may or may not be equal to their respective DAC values. Therefore, given all possible combinations of camera modules, it's possible to determine which DAC values ​​are still required. Considering the slight differences between each target camera module, a method is needed to calculate the DAC values ​​of the camera module at different focusing distances for the same mobile phone model.

[0078] In this embodiment, for any target camera module, the required DAC values ​​for different focal lengths can be determined first. Then, the DAC values ​​at the corresponding focusing distances are pre-measured and burned in. Afterward, the preset near-focus ratio and preset hyperfocal distance ratio at these focal lengths are calculated. The target camera module may have one or more preset near-focus ratios, or even none. The same applies to the preset hyperfocal distance ratio. This mainly depends on the focal length overlap range between the target camera module and other target camera modules.

[0079] For example, in this embodiment, the periscope camera module of the mobile phone, when lit together with a general wide-angle camera module, has a focal length overlap range of 30-900cm. The two endpoints of this focal length overlap range are equal to its own near-focal distance and hyperfocal distance. Therefore, the periscope camera module can achieve focus synchronization based on its own DAC values ​​corresponding to its near-focal distance and hyperfocal distance, without needing to measure and calculate a preset near-focal distance ratio and a preset hyperfocal distance ratio. However, for a general wide-angle camera module, it is necessary to measure the DAC value at 30cm and 900cm to calculate the preset near-focal distance ratio and preset hyperfocal distance ratio, as shown in the following formula:

[0080] K1=(Dac 30 -Dac 超 ) / (Dac 近 -Dac 超 )*100%

[0081] K2=(Dac 900 -Dac 超 ) / (Dac 近 -Dac 超 )*100%

[0082] Where K1 is the preset near-focus ratio, K2 is the preset hyperfocal distance ratio, and Dac 30 The DAC value is the value when focused at 30cm. 900 The Dac value is the value when focused at 900 cm. 近 This is the Dac value when focusing at close focal length. 超 This is the Dac value when focusing at hyperfocal distance.

[0083] For the same type of camera module, each module has slightly different values, resulting in different DAC values ​​when focusing at the same distance. It's easy to understand that each camera module of the same model will have a different DAC value for near-focal distance. 近 Value and hyperfocal distance Dac 超 The values ​​are all slightly different.

[0084] Therefore, by using the above method, for the same type of camera module, a certain number of camera modules can be selected for measurement and recording, thereby obtaining the required preset near-focus ratio and preset hyperfocal distance ratio.

[0085] In practical applications, based on the actual lighting combination, and combined with the measured and burned near-focal distance DAC, 近 Value and hyperfocal distance Dac 超This value determines the required Dac value when the camera is illuminated alongside different camera modules, i.e., the Dac value corresponding to the focus overlap range. For example, when a periscope camera module and a general wide-angle camera module are illuminated together, the focus overlap range is 30-900cm. After obtaining the preset near-focus ratio and preset hyperfocal distance ratio of the general wide-angle camera module relative to the periscope camera module, the Dac values ​​for focusing at 30cm and 900cm can be calculated using the following formulas:

[0086] Dac 30 =Dac 超 +(Dac 近 -Dac 超 )*K1

[0087] Dac 900 =Dac 超 +(Dac 近 -Dac 超 )*K2

[0088] Among them, Dac 30 This refers to the DAC value of a typical wide-angle camera module when focusing at 30cm. 900 This refers to the DAC value of a typical wide-angle camera module when it is focused at 900cm.

[0089] Step 104: Based on the focal length overlap range, preset near-focus ratio, and preset hyperfocal distance ratio of the two target camera modules, control the two target camera modules to synchronize focus.

[0090] In this embodiment, focusing refers to changing the image distance, which is essentially changing the distance from the lens optical center to the image sensor. When two target camera modules are working simultaneously, they need to focus synchronously within the focal length overlap range.

[0091] As is easily understood, a camera module mainly consists of a lens, a voice coil motor, a photosensitive chip, and a driver chip. The driver chip precisely controls the movement distance and direction of the coil within the motor, thereby moving the lens to achieve perfect focusing. Specifically, the mobile phone control terminal inputs a DAC value (or DAC code value) to the driver chip. The driver chip then supplies current to the voice coil motor's coil based on the DAC value, utilizing the magnetic field within the voice coil motor to generate the force that drives the coil (lens).

[0092] During focus synchronization, the DAC values ​​of the input motor drive chips of the two target camera modules can be calculated based on the focal length overlap range, preset near-focus ratio, and preset hyperfocal distance ratio of the two target camera modules. Then, based on the DAC values ​​of their respective input motor drive chips, the two target camera modules can be controlled to perform focus synchronization.

[0093] Specifically, based on the focal length overlap range, a first camera module and a preset close-focus ratio are determined from two target camera modules. The preset close-focus ratio is the close-focus ratio coefficient of the first camera module relative to the other target camera module, and it is pre-programmed. As mentioned above, for a target camera module, its preset close-focus ratio may be one or more, or even none, depending on the other target camera module that it is paired with. If the close-focus distance of the target camera module is less than or equal to the close-focus distance of the other target camera module, then the target camera module is set as the first camera module, and the preset close-focus ratio corresponding to the other target camera module is selected from its preset close-focus ratios.

[0094] Then, based on the pre-programmed near-focal distance (Dac) and hyperfocal distance (Dac) values ​​of the first camera module, as well as the preset near-focal distance ratio, the near-focal distance (Dac) value corresponding to the first camera module within the focal length overlap range is calculated. For details, please refer to the preceding content.

[0095] Similarly, based on the focal length overlap range, a second camera module and a preset hyperfocal distance ratio are determined from the two target camera modules. The preset hyperfocal distance ratio is the hyperfocal distance ratio coefficient of the second camera module relative to the other target, and it is pre-programmed. As mentioned above, for a target camera module, its preset near-focus ratio may be one or more, or even none, specifically determined based on the other target camera module that it is combined with and illuminated. If the hyperfocal distance of the target camera module is less than or equal to the hyperfocal distance of the other target camera module, then the target camera module is designated as the second camera module; and the preset hyperfocal distance ratio corresponding to the other target camera module is selected from its preset hyperfocal distance ratios.

[0096] Then, based on the pre-recorded near-focal distance Dac value, hyperfocal distance Dac value, and preset hyperfocal distance ratio of the second camera module, the hyperfocal distance Dac value corresponding to the focal length overlap range of the second camera module is obtained.

[0097] In addition, after calculating the near focal length Dac value or hyperfocal length Dac value corresponding to the focal length overlap range, the obtained Dac value can be verified. The verification steps include:

[0098] Determine whether the Dac value is within ±25% of the preset correction Dac value;

[0099] If they are present, the two target camera modules will successfully synchronize their focus; otherwise, the two target camera modules will fail to synchronize their focus.

[0100] The verification method is as follows:

[0101] Combination Figure 4 As shown. Substitute the values ​​into the formula to calculate the known focal length of the lens, and the minimum focal length D.inf Hyperfocal distance D macro And AF near-focus correction Dac inf Hyperfocal correction Dac macro The distance in D can be obtained using the following formula. target The ratio k:

[0102] A = (D inf *f) / (D inf -f)

[0103] B = (D) macro *f) / (D macro -f)

[0104] C = (D target *f) / (D target -f)

[0105] M=(AB) / (Dac inf -Dac macro )

[0106] D actarget =(C-B+M*Dac) macro ) / M

[0107] k=(Dac target -Dac inf ) / (Dac macro -Dac inf )*100%

[0108] The main method utilizes Gaussian formula in optical imaging: 1 / u + 1 / v = 1 / f, where u is the object distance, v is the image distance, and f is the lens focal length. Here, A represents the image distance at the telephoto end, B represents the image distance at the near-focal end, C represents the image distance at the target distance, and D represents the image distance at the target distance. inf For the telephoto object distance, D macro For near-focal distance, D target The target object distance is given. These three image distances (A / B / C) are all derived using the Gaussian formula.

[0109] Where M is the ratio of the telephoto image distance minus the near-focal distance image distance to the telephoto Dac minus the near-focal distance Dac. It should be explained that the motor's Dac value and lens displacement have a linear relationship, such as... Figure 4 As shown, M is the calculated slope. With the slope M, the target value's Dac can be calculated using the target image distance (corresponding lens displacement) and the near focal length image distance (corresponding lens displacement). target It's worth it, since we already have Dac target Then k can be calculated using the proportional formula.

[0110] Following the method described above, the required Dac for any target value (i.e., focus distance) can be calculated according to actual needs. target Value, this Dac target The value can be used as the correction DAC value.

[0111] It should be noted that this method differs somewhat in accuracy from the first method, as the first method uses measured values ​​for proportional calculations, resulting in higher accuracy. However, this method is helpful for verifying and calibrating focus-synchronization DACs, preventing unclear focusing.

[0112] In summary, this embodiment provides a focus synchronization method for multi-camera module applications. It involves identifying two target camera modules to be illuminated; then acquiring the focal length parameters of each target camera module; subsequently determining the focal length overlap range, a preset near-focus ratio, and a preset hyperfocal distance ratio based on these parameters; and finally controlling the two target camera modules to synchronize focus based on these parameters. Thus, when a mobile phone has multiple camera modules, precise focus synchronization between two target camera modules can be achieved, and the calibration results can be corrected based on the calibration DAC value.

[0113] Based on the same inventive concept, combined with Figure 5 As shown, this embodiment of the invention also provides a focus synchronization device 10 for multi-camera module applications, including a camera lighting module 11, a data acquisition module 12, a calculation and processing module 13, and a focus synchronization module 14.

[0114] Camera illumination module 11 is used to identify the two target camera modules that are illuminated;

[0115] Data acquisition module 12 is used to acquire the focal length parameters of the two target camera modules respectively;

[0116] The calculation and processing module 13 is used to determine the focal overlap range, the preset near-focus ratio, and the preset hyperfocal distance ratio based on the focal length parameters of the two target camera modules.

[0117] The focus synchronization module 14 is used to control the two target camera modules to perform focus synchronization based on the focal length overlap range, preset near-focus ratio and preset hyperfocal distance ratio of the two target camera modules.

[0118] In an optional implementation, the computation processing module 13 is further configured to:

[0119] Focal length parameters include near focal length and hyperfocal length;

[0120] Based on the focal length parameters of the two target camera modules, the focal length overlap range is determined, including:

[0121] Select the maximum near focal length from the two target camera modules;

[0122] The maximum hyperfocal distance is selected from the hyperfocal distances of the two target camera modules; the range between the maximum near focal distance and the maximum hyperfocal distance constitutes the focal length overlap range.

[0123] In an alternative implementation, the focus synchronization module 14 is further configured to:

[0124] Based on the focal overlap range, preset near-focus ratio, and preset hyperfocal distance ratio of the two target camera modules, the Dac values ​​of the input motor drive chips corresponding to the focal overlap range of the two target camera modules are calculated respectively.

[0125] Based on the DAC value of their respective input motor driver chips, the two target camera modules are controlled to synchronize focus.

[0126] In an alternative implementation, the focus synchronization module 14 is further configured to:

[0127] Based on the focal length overlap range, the first camera module and the preset close-focus ratio are determined from the two target camera modules. The preset close-focus ratio is the close-focus ratio coefficient of the first camera module relative to the other target camera module, and it is obtained in advance.

[0128] Based on the pre-recorded near focal length Dac, hyperfocal length Dac values ​​of the first camera module and the preset near focal length ratio, the near focal length Dac value corresponding to the focal length overlap range of the first camera module is obtained.

[0129] Based on the focal length overlap range, the second camera module and the preset hyperfocal distance ratio are determined from the two target camera modules. The preset hyperfocal distance ratio is the hyperfocal distance ratio coefficient of the second camera module relative to the other target, and it is obtained in advance.

[0130] Based on the pre-recorded near-focal distance Dac value, hyperfocal distance Dac value, and preset hyperfocal distance ratio of the second camera module, the hyperfocal distance Dac value corresponding to the focal length overlap range of the second camera module is obtained.

[0131] In an alternative implementation, the focus synchronization module 14 is further configured to:

[0132] From the two target camera modules, the target camera module with the smaller near focal length is selected as the first camera module;

[0133] Obtain the preset near-focus ratio of the first target camera module relative to another target camera module.

[0134] In an alternative implementation, the focus synchronization module 14 is further configured to:

[0135] From the two target camera modules, the target camera module with the smaller hyperfocal distance is selected as the second camera module;

[0136] Obtain the preset hyperfocal distance ratio of the second target camera module relative to another target camera module.

[0137] In an alternative implementation, the focus synchronization module 14 is further configured to:

[0138] Determine whether the Dac value is within ±25% of the preset correction Dac value;

[0139] If they are present, the two target camera modules will successfully synchronize their focus; otherwise, the two target camera modules will fail to synchronize their focus.

[0140] In summary, this embodiment provides a focus synchronization device for multi-camera module applications. It identifies two target camera modules to be illuminated; then, it acquires the focal length parameters of each target camera module; based on these parameters, it determines the focal length overlap range, a preset near-focus ratio, and a preset hyperfocal distance ratio; finally, it controls the two target camera modules to synchronize focus based on these parameters. Thus, when a mobile phone has multiple camera modules, precise focus synchronization between two target camera modules can be achieved, and the calibration result can be corrected based on the calibration DAC value.

[0141] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working process of the focusing synchronization device for the multi-camera module application described above can be referred to the corresponding process in the aforementioned method, and will not be elaborated further here.

[0142] Based on the above, this embodiment provides a readable storage medium storing a computer program, which, when executed by a processor, implements the focus synchronization method for multi-camera module applications in any of the aforementioned embodiments.

[0143] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working process of the readable storage medium described above can be referred to the corresponding process in the aforementioned method, and will not be elaborated further here.

[0144] In summary, this embodiment provides a focus synchronization method, apparatus, and electronic device for multi-camera module applications. The method involves identifying two target camera modules to be illuminated; then acquiring the focal length parameters of each target camera module; subsequently determining the focal length overlap range, a preset near-focus ratio, and a preset hyperfocal distance ratio based on these parameters; and finally controlling the two target camera modules to synchronize focus based on these parameters. Thus, when a mobile phone has multiple camera modules, precise focus synchronization between two target camera modules can be achieved, and the calibration results can be corrected based on the calibration DAC value.

[0145] The above are merely various embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A focus synchronization method for multi-camera module applications, characterized in that, include: Identify the two target camera modules that have been illuminated; Obtain the focal length parameters of the two target camera modules respectively; The focal length parameters include near focal length and hyperfocal length; Choose the larger near focal length from the two target camera modules; Choose the larger hyperfocal distance from the two target camera modules; The range between the larger near focal length and the larger hyperfocal length constitutes the focal length overlap range. Based on the focal length overlap range, a first camera module and a preset close-focus ratio are determined from the two target camera modules. The preset close-focus ratio is the close-focus ratio coefficient of the first camera module relative to the other target camera module, and it is obtained by pre-programming. Based on the focal length overlap range, a second camera module and a preset hyperfocal distance ratio are determined from the two target camera modules. The preset hyperfocal distance ratio is the hyperfocal distance ratio coefficient of the second camera module relative to the other target, and is obtained by pre-programming. Based on the focal length overlap range, preset near-focus ratio, and preset hyperfocal distance ratio of the two target camera modules, the two target camera modules are controlled to synchronize focus.

2. The focusing synchronization method for multi-camera module applications according to claim 1, characterized in that, The step of controlling the two target camera modules to synchronize focus based on the focal length overlap range, preset near-focus ratio, and preset hyperfocal distance ratio of the two target camera modules includes: Based on the focal length overlap range, preset near-focus ratio, and preset hyperfocal distance ratio of the two target camera modules, the Dac values ​​of the input motor drive chips corresponding to the focal length overlap range of the two target camera modules are calculated respectively. Based on the DAC value of their respective input motor driver chips, the two target camera modules are controlled to synchronize focus.

3. The focusing synchronization method for multi-camera module applications according to claim 2, characterized in that, The step involves calculating the Dac values ​​of the input motor drive chips for the two target camera modules within their respective focal length overlap ranges, preset near-focus ratios, and preset hyperfocal distance ratios, including: Based on the pre-programmed near focal length Dac and hyperfocal length Dac values ​​of the first camera module and the preset near focal length ratio, the near focal length Dac value of the first camera module corresponding to the focal length overlap range is obtained. Based on the pre-recorded near focal length Dac value, hyperfocal length Dac value, and preset hyperfocal length ratio of the second camera module, the hyperfocal length Dac value corresponding to the focal length overlap range of the second camera module is obtained.

4. The focusing synchronization method for multi-camera module applications according to claim 3, characterized in that, The step of determining the first camera module and the preset near-focus ratio from the two target camera modules based on the focal length overlap range includes: From the two target camera modules, the target camera module with the smaller near focal length is selected as the first camera module; Obtain the preset close-focus ratio of the first camera module relative to another target camera module.

5. The focusing synchronization method for multi-camera module applications according to claim 3, characterized in that, The step of determining the second camera module and the preset hyperfocal distance ratio from the two target camera modules based on the focal length overlap range includes: From the two target camera modules, the target camera module with the smaller hyperfocal distance is selected as the second camera module; Obtain the preset hyperfocal distance ratio of the second camera module relative to another target camera module.

6. The focusing synchronization method for multi-camera module applications according to claim 2, characterized in that, The method further includes: Determine whether the Dac value is within ±25% of the preset correction Dac value; If they are present, the two target camera modules will successfully synchronize their focus; otherwise, the two target camera modules will fail to synchronize their focus.

7. A focusing synchronization device for multi-camera module applications, characterized in that, include: The camera illumination module is used to identify the two target camera modules that are illuminated. The data acquisition module is used to acquire the focal length parameters of the two target camera modules respectively; The focal length parameters include near focal length and hyperfocal length; The calculation and processing module is used to select the larger near focal length from the near focal lengths of the two target camera modules; and to select the larger hyperfocal length from the hyperfocal lengths of the two target camera modules; wherein the range between the larger near focal length and the larger hyperfocal length constitutes a focal length overlap range; and based on the focal length overlap range, to determine a first camera module and a preset near focal ratio from the two target camera modules, wherein the preset near focal ratio is a near focal ratio coefficient of the first camera module relative to the other target camera module, and is pre-programmed. Based on the focal length overlap range, a second camera module and a preset hyperfocal distance ratio are determined from the two target camera modules. The preset hyperfocal distance ratio is the hyperfocal distance ratio coefficient of the second camera module relative to the other target, and is obtained by pre-programming. The focus synchronization module is used to control the two target camera modules to perform focus synchronization based on the focal length overlap range, preset near-focus ratio, and preset hyperfocal distance ratio of the two target camera modules.

8. An electronic device, characterized in that, The electronic device includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the focus synchronization method for the multi-camera module application as described in any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, It stores a computer program that, when executed by a processor, implements the focus synchronization method for a multi-camera module application as described in any one of claims 1-6.

Images