5G mobile phone communication terminal capable of automatically focusing and projecting and automatic focusing method thereof

Abstract

The invention discloses an automatic focusing projection 5G mobile phone communication terminal and an automatic focusing method thereof. The terminal comprises a projection module, a focusing acquisition camera, a focusing driving device, a central processing unit, a motion sensor unit and a radio frequency communication unit. The central processing unit is used for carrying out image acquisition and contrast analysis on a projection picture, searching a contrast peak value based on a gradient ascending method to determine an optimal focusing position, and outputting a driving signal to control the focusing driving device to move the lens group along the optical axis to realize millisecond-level automatic focusing; and meanwhile, compensation is carried out by combining motion data such as a gyroscope and an accelerometer, so that a picture is kept clear in a moving scene. According to the terminal, flight time distance measurement can be selected to realize cooperative focusing of coarse adjustment and fine adjustment, and a stepping motor can be replaced by magnetic suspension driving so as to reduce mechanical wear. Compared with a manual focusing mobile phone, real-time, quick and accurate automatic focusing is realized, and the mobile phone has the advantages of convenience in operation, high stability and rich application scenes.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of electronic communication and optical display technology, and particularly relates to an automatically focusing projection 5G mobile phone communication terminal and an automatic focusing method thereof. BACKGROUND

[0002] The existing projection display equipment is mainly fixed projectors, which are bulky and heavy, and usually need stable power supply environment and external audio and video signal source to work, lacking portability and independence. Such products are more suitable for indoor fixed use, and it is difficult to meet the immediate use needs of users in mobile office, outdoor demonstration and entertainment and leisure scenarios.

[0003] Traditional smart phones take communication, calculation and multimedia application as the core function, although they have high portability, but they do not support large size projection display. When sharing the screen with multiple people, the smart phone is limited by the screen size and cannot replace the projector to play the advantage of large screen display.

[0004] Therefore, some manufacturers have proposed a mobile phone terminal scheme integrating projection function, namely so-called "projection mobile phone". In the early design of such products, a manual focusing structure is mostly used, and the user needs to adjust the optical lens mechanically through a knob or sliding mechanism to obtain a clear picture. However, manual focusing has obvious deficiencies: first, the use steps are complicated, and the terminal position or projection distance needs to be adjusted every time it changes; second, the mechanical transmission parts are prone to wear in frequent operation, resulting in a decrease in precision; third, the adjustment result depends on the user's subjective judgment, and often produces deviation, making it difficult to ensure the continuous clarity of the picture.

[0005] With the improvement of user requirements for mobile projection experience, some projection mobile phones try to introduce automatic focusing technology. However, these technologies are mostly simple transplantation of traditional camera automatic focusing schemes, and lack targeted optimization for the characteristics of the projection scene. In camera shooting, picture focusing only involves small range imaging under instantaneous shutter, while projection picture involves large area and continuous optical imaging, which puts higher requirements on focusing speed, stability and adaptive ability in dynamic environment. The existing technology is obviously insufficient in this regard.

[0006] In addition, the existing automatic focusing method also has shortcomings in algorithm and hardware cooperation. Most schemes only rely on single image contrast calculation, and lack deep coupling with motion sensors and optical driving mechanisms. When the projection mobile phone is used in a mobile or vibrating environment, the algorithm is difficult to respond to environmental disturbances in time, resulting in delayed or failed focusing, and blurred and jittered picture. On the other hand, the existing driving structure mostly uses traditional motors, which are limited by step precision and mechanical friction, and are difficult to achieve sub-micron precise displacement control, with limited service life.

[0007] In summary, the prior art has the following significant deficiencies: 1. Fixed projectors are large in size and cannot be portable, and do not have communication functions; 2. Ordinary smartphones lack projection functions and cannot meet the demand for large-screen sharing; 3. Projection phones generally rely on manual focusing, which is tedious, severely worn, and limited in precision; 4. Existing automatic focusing algorithms are transplanted from the camera field and lack targeted optimization for projection scenes; 5. There is a lack of coordination with motion sensors and optical driving devices, and the picture stability is poor in a moving scene; 6. The driving mechanism is limited by mechanical friction and precision bottlenecks, making it difficult to support high-frequency and long-time dynamic focusing.

[0008] Therefore, how to integrate projection functions in a mobile communication terminal and achieve fast, accurate, stable and sustainable automatic focusing has become a technical problem that needs to be solved in the field.

[0009] Therefore, the prior art still needs to be improved. SUMMARY

[0010] In view of the above problems of the prior art that projection phones rely on manual focusing, automatic focusing is slow, the picture is unstable in a dynamic scene, the driving device is easily worn, and it is difficult to ensure clarity in low light environments, the existing solutions cannot meet the actual needs of users in mobile office, entertainment and outdoor applications. Therefore, the present application provides an automatic focusing projection 5G mobile communication terminal, which integrates a projection module, a focusing acquisition camera, a focusing driving device, a central processing unit and a motion sensor, realizes fast, accurate and stable automatic focusing, and further introduces a focusing strategy combining distance measurement coarse adjustment and gradient ascent fine adjustment, a dynamic compensation mechanism, a magnetic suspension driving structure and an infrared assisted focusing scheme in low light environment. Therefore, the limitations of the prior art are effectively overcome, and the applicability and user experience of the terminal are significantly improved.

[0011] The technical solutions of the present application are as follows: The present application provides an automatic focusing projection 5G mobile communication terminal, comprising: a projection module, a focusing acquisition camera, a focusing driving device, a central processing unit, a motion sensor unit and a radio frequency communication unit; The focusing acquisition camera is used to acquire the image of the projected picture of the projection module; The central processing unit calculates the contrast metric based on the image, and uses the gradient ascent method to search for the peak value of the contrast metric to determine the best focusing position; The central processing unit outputs a driving signal to the focusing driving device, so that the lens group of the projection module moves to the best focusing position, and real-time automatic focusing is realized. The central processing unit also performs dynamic compensation based on the angular velocity or acceleration data of the motion sensor unit, so as to maintain projection clarity in a moving scene.

[0012] In one embodiment, the focusing driving device is a micro stepping motor, the step angle of the stepping motor is not greater than 1.8°, and the linear displacement precision corresponding to a single step is 5-10 microns.

[0013] In one embodiment, the central processing unit uses second-order difference or threshold criterion as a stop condition in the search process, so as to complete focusing within milliseconds.

[0014] In one embodiment, the motion sensor unit includes a gyroscope, an accelerometer, and a geomagnetic sensor, which are used to provide kinematic data to correct the contrast metric.

[0015] In one embodiment, the projection module is a micro projection unit, supports a projection size of not less than 100 inches, and has an over-temperature, over-voltage, and over-current protection circuit.

[0016] In one embodiment, the terminal further includes a night vision camera and a near-infrared light emitting device, which are used to assist the focusing acquisition camera in collecting clear images under low light conditions.

[0017] In one embodiment, the terminal includes a battery with a capacity of not less than 20,000 mAh, supports 66W fast charging, and can continuously project for at least 15 hours under full power.

[0018] In one embodiment, the automatic focusing includes: realizing coarse adjustment based on time-of-flight ranging or infrared ranging, and realizing fine adjustment based on the contrast metric of the focusing acquisition camera, so as to realize cooperative focusing of "coarse adjustment + fine adjustment".

[0019] In one embodiment, the focusing driving device is a magnetic levitation driving mechanism, which controls the movement of the lens group along the optical axis by electromagnetic force, so as to realize frictionless sub-micron displacement adjustment.

[0020] Another aspect of the present application also provides an automatic focusing method of an automatically focusable projection 5G mobile phone communication terminal, the method comprising: collecting a projection picture image; calculating a contrast metric based on the image and searching for a contrast peak value using a gradient ascent method; outputting a driving signal to a focusing driving device to drive the lens group to move to a best focusing position; Compensation in combination with motion sensor data during lens movement; When insufficient ambient light is detected, near-infrared auxiliary lighting is enabled to ensure accuracy of the focusing process.

[0021] In summary, the present application proposes an automatic focusing projection 5G mobile communication terminal, through the depth cooperation of the projection module, focusing acquisition camera, central processing unit, focusing driving device and motion sensor, realizes fast, accurate and stable automatic focusing under different projection distances, different postures and different lighting conditions. The present application adopts a double-layer search strategy combining range finding coarse adjustment and contrast fine adjustment, and completes focusing within milliseconds; motion sensor data compensation is introduced to maintain clarity in dynamic scenes; at the same time, magnetic levitation driving is used to replace traditional stepping motors, achieving frictionless, long-life, high-precision lens adjustment; combined with night vision camera and infrared auxiliary lighting, the applicability of weak light scenes is expanded. This technical solution not only breaks through the limitations of existing projection phones relying on manual focusing, instability in dynamic scenes, and failure in low light environments, but also exhibits higher practicality and reliability in terms of battery life and system integration, which can significantly improve user experience and promote the integration of mobile projection and communication terminals.

[0022] Compared with existing projection mobile phones and automatic focusing solutions, the present application exhibits several unexpected technical advantages: Firstly, in terms of focusing speed, traditional automatic focusing mostly relies on a single contrast search algorithm, which has a wide search interval and slow convergence, often taking hundreds of milliseconds or even seconds to complete focusing. The present application uses a time-of-flight ranging module or infrared ranging to quickly lock the coarse adjustment interval, and applies gradient ascent method for fine adjustment search within the interval, shortening the iteration path. Experimental results show that the average focusing time of the present application under typical 1.5 meter projection distance can be shortened to 50 milliseconds, which is an order of magnitude higher than existing solutions, belonging to unexpected technical effects.

[0023] Secondly, in terms of focusing accuracy and stability, existing solutions mostly do not consider the inevitable movement and shaking of the terminal during use, resulting in significant decline in picture clarity. The present application introduces motion sensor data into the contrast algorithm in real time, and performs posture compensation at the algorithm level, so that the contrast curve still maintains clear peak characteristics in dynamic scenes, ensuring continuous clarity of the picture in moving state. This effect breaks through the limitation of existing automatic focusing only in static scenes, and belongs to the improvement that existing technology has not anticipated.

[0024] Again, in terms of driving reliability, traditional projection phones generally use a miniature stepping motor as the only focusing actuator, which is prone to wear, loss of step or noise problems over time. The magnetic suspension driving alternative proposed by the application uses electromagnetic suspension to achieve frictionless displacement, avoiding mechanical wear, significantly extending the service life, and achieving sub-micron adjustment accuracy. This driving method is first applied in the field of projection phones, and its long-term stability and low noise characteristics have brought unexpected breakthroughs to the industry.

[0025] In addition, in terms of low light and special environment adaptability, existing focusing algorithms usually rely on visible light images, which are prone to failure when there is insufficient light or lack of texture in the picture. The application introduces a near-infrared lighting and night vision camera coordination mechanism, enabling automatic focusing to work normally in completely dark or low-light scenes. This capability exceeds the expectations of ordinary users and technical personnel for the usability of projection phones, and is a typical unexpected technical effect.

[0026] Finally, in terms of endurance and energy consumption control, the application combines a large-capacity battery with a power consumption management strategy to achieve more than 15 hours of continuous projection time, while ensuring the stable operation of focusing and communication functions. In the context of existing technology, long-time projection is often accompanied by rapid power consumption and overheating problems. The application balances energy efficiency and system stability, further highlighting its uniqueness.

[0027] In summary, the application not only far exceeds existing technology in terms of focusing speed, accuracy and stability, but also achieves unexpected improvements in dynamic compensation, frictionless driving, low-light adaptability and energy management. These improvements cannot be derived by those skilled in the art based on conventional ideas, and reflect significant creativity. BRIEF DESCRIPTION OF DRAWINGS

[0028] The application will be further described below in conjunction with the drawings and embodiments. In the drawings: Figure 1 A structural block diagram of the automatically focusable projection 5G mobile phone communication terminal provided by the application is provided. Figure 2 A principle block diagram of the automatically focusable projection 5G mobile phone communication terminal provided by the application is provided. Figure 3 A step flowchart of the automatic focusing method of the automatically focusable projection 5G mobile phone communication terminal provided by the application is provided. DETAILED DESCRIPTION

[0029] To make the purpose, technical solutions and effects of the application clearer and more explicit, the application will be further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the application and not to limit the application. The embodiments of the application are described below with reference to the drawings.

[0030] The automatic focusing projection 5G mobile phone communication terminal provided by the embodiment is used for Figure 1 、 Figure 2 , and comprises: a projection module 1, a focusing acquisition camera 2, a focusing driving device 3, a central processing unit 4, a motion sensor unit 5 and a radio frequency communication unit 6. The focusing acquisition camera 2 is used for acquiring an image of a projection picture projected by the projection module 1. The central processing unit 4 calculates a contrast measure based on the image and searches a peak value of the contrast measure by using a gradient ascent method to determine an optimal focusing position. The central processing unit 4 outputs a driving signal to the focusing driving device 3, so that a lens group of the projection module 1 moves to the optimal focusing position, and real-time automatic focusing is realized. The central processing unit 4 also performs dynamic compensation based on angular velocity or acceleration data of the motion sensor unit 5, so that projection clarity is maintained in a moving scene.

[0031] The overall architecture of the automatic focusing projection 5G mobile phone communication terminal is as follows: the projection module 1 and an optical lens group thereof are fixed in a mobile phone internal shell, the lens group can be linearly displaced along an optical axis; the focusing acquisition camera 2 is arranged near a projection light path to acquire a projection picture; the focusing driving device 3 (a micro stepping motor or a magnetic suspension driving device) transmits driving force to the lens group through mechanical transmission; the central processing unit 4 (CPU / SoC) is responsible for image acquisition, contrast calculation, gradient ascent search, motion compensation and driving control; the motion sensor unit 5 (including a gyroscope and an accelerometer) provides real-time posture and acceleration information; and the radio frequency communication unit 6 is responsible for 5G and other wireless connections. The overall architecture guarantees real-time performance and reliability of image acquisition, judgment, driving and motion information closed-loop cooperation.

[0032] Specifically, the projection module 1 is composed of a high-efficiency light source assembly (such as an RGB LED or a single-mode laser), a digital light processing device (a DMD chip or an LCoS chip), and a multi-piece aspheric lens group. The output brightness of the light source is adjustable in the range of 200-400 lumens, ensuring clear projection even in complex lighting environments. The lens group uses aspheric elements to reduce distortion and aberration, and a moving channel along the optical axis is reserved for the focus driving device 3 to perform precise displacement. The focus acquisition camera 2 is installed near the projection module 1, with an imaging field of view covering the main projection area, and its pixel is not less than 2 million, which can acquire and transmit the projection image to the central processing unit 4 in real time. The central processing unit 4 selects a multi-core SoC with GPU co-processing capability, runs a real-time operating system, and can complete tasks such as image acquisition, contrast measurement, gradient search, motion compensation, and drive signal output within 10ms. The motion sensor unit 5 includes a gyroscope and an accelerometer, with a sampling rate as high as 1kHz. After Kalman filtering fusion, the data is input to the central processing unit for dynamic correction. Through the close cooperation of multiple modules, the invention realizes the dual attributes of communication and high-performance projection in a single terminal.

[0033] The central processing unit 4 adopts the latest Mediatek MT6878 5G SOC, which adopts the industry-leading TSMC third-generation 4nm chip production process. MT6878 integrates the latest ARMv8.2 CPU IP, with 4 big cores (CA78) and 4 small cores (CA55), and the latest OpenOS, which can support various modern smartphone applications, including engaging multimedia experiences, heavy-duty games, and multitasking productivity. MT6878 also integrates the Arm Mali-G615 MC2 GPU IP, which can render 2D and 3D graphics to enhance visual experience. The MDLA in MT6878 can meet the latest AI trends, achieving maximum effective performance in AI multimedia, AI games, AI cameras, and modern social video experiences. The MDLA is also designed to ensure that AI-enhanced technology can work sustainably and for the longest duration under various conditions. MT6878 combines CPU, DSP, and hardware co-processor, providing a powerful modem subsystem that supports NR Sub6, LTE Cat 16, Category 24 HSDPA downlink and Category 7 HSUPA uplink data rates, and Class 12 GPRS and EDGE. MT6878 is also used with Mediatek's latest Wi-Fi 6E / BT 5.4 connection chip MT6637, which can provide the most dynamic and dominant connection solution in the industry.

[0034] The projection module 1 adopts a Yaming optical FLA8+ micro projection module, preferably with a size of 44.2mm*44.5mm*10mm, which can be perfectly embedded in the mobile phone. It supports a maximum of 100-inch resolution of 854*480 projection screen, and has over-temperature, over-voltage and over-current protection functions. The module has a precise focusing mechanical structure, which realizes real-time automatic fast and accurate focusing in combination with a high-precision stepping motor. In particular, after the mobile phone moves, the focal length changes and the projection screen is not clear, and this focusing system can perfectly solve such problems.

[0035] The audio PA adopts an AW88394 digital power amplifier, which is a digital interface Smart K audio power amplifier integrated with Boost, which can realize 10.25V high-voltage output and improve output power; the built-in DSP integrates the latest sound effect and loudspeaker protection algorithm MEC, and the output power is 5.3W (THD+N=1% @8Ω load), and the overall efficiency is as high as 80%. The 2W high-power loudspeaker strengthens the human voice penetration, and ensures that the sound played by the mobile phone can be clearly heard in a noisy environment.

[0036] The radio frequency communication unit 6 adopts an MTK sheet MT6197, which is a multi-mode multi-band radio frequency system chip adopting a 12-nanometer FinFET process, supporting 2G to 5G full-standard communication, and having high integration and advanced radio frequency characteristics.

[0037] In a further embodiment, the focusing driving device 3 is a micro stepping motor, and the step angle of the stepping motor is not greater than 1.8°, and the linear displacement precision corresponding to a single step is 5-10 microns.

[0038] Specifically, in the embodiment of the application, the focusing driving device 3 adopts a micro stepping motor, the step angle of which is typically 1.8°, and the linear displacement is realized through a 3mm diameter screw transmission mechanism. When 1 / 32 micro-step subdivision is adopted, the displacement per step can be accurately 0.25 microns, which fully meets the needs of high-definition picture focusing. The central processing unit 4 controls the motor through a driving chip, and the output pulse sequence follows a trapezoidal speed curve: first accelerate to the highest speed (not more than 2000 steps / second), keep constant speed at this speed, then decelerate and stop, to avoid out-of-step or vibration caused by inertia. The motor is provided with a Hall limit switch and a current detection circuit, which automatically triggers a stop command when the lens moves to the boundary position, or automatically enters a protection mode and retreats to a safe interval when an overload current is detected. In actual tests, the average response time of the stepping motor driving scheme is controlled within 100-150 milliseconds, the repeated positioning accuracy is ±1.5 microns, and the cumulative running life exceeds 1000 hours without significant degradation.

[0039] In another embodiment, the central processing unit 4 employs a second-order difference or threshold criterion as a stopping condition in the search process to complete focusing within milliseconds.

[0040] Specifically, the central processing unit 4 executes a contrast-based focusing algorithm. The system first pre-processes the image acquired by the focusing camera 2, including median filter denoising, histogram equalization, and brightness normalization, to eliminate the influence of environmental light changes. Then the picture is divided into multiple ROIs (regions), each of which is 64x64 or 128x128 pixels, and the gray variance σ² and edge intensity integral Σ|∇I| are calculated respectively. A unified contrast index C = α·σ² + β·Σ|∇I| is obtained through a linear fusion formula, where α and β are dynamic adjustment weights, ensuring that the algorithm can stably operate in both high-texture and low-texture scenes. In the search process, the central processing unit drives the lens group to move according to a preset step size (e.g., 5-10 microns) and calculates the contrast index change in real time. The gradient ascent method is used, and when ΔC approaches 0 and Δ²C changes from positive to negative, it is determined that the peak focus point is reached. The average focusing time of this method in the test scene is 50 milliseconds, with an accuracy rate of more than 98%, which is 3-4 times faster than the traditional global search method.

[0041] In further embodiments, the motion sensor unit 5 includes a gyroscope, an accelerometer, and a geomagnetic sensor for providing kinematic data to correct the contrast metric.

[0042] More specifically, the module of the motion sensor unit 5 is composed of a three-axis gyroscope and a three-axis accelerometer with a sampling frequency higher than 500Hz. The central processing unit 4 fuses the angular velocity and acceleration based on an extended Kalman filter to output the attitude angle and acceleration vector in real time. When calculating the contrast curve, this attitude information is used to correct the positional offset and blurring effect of the ROI region. When the angular velocity is greater than 30° / s or the acceleration is greater than 1.5g, the system immediately reduces the moving speed of the stepper motor and narrows the search step size to prevent focusing failure due to rapid movement. In a moving or vibrating environment, the invention can still complete focusing within 100 milliseconds, with a success rate of more than 95%.

[0043] The gyroscope uses TDK InvenSense's ICM-42607-P, which is a high-performance 6-axis motion tracking sensor (IMU) that integrates a 3-axis gyroscope and a 3-axis accelerometer in a compact package, enabling screen rotation, game control, augmented reality, fitness tracker step counting, motion tracking, inertial navigation, etc.

[0044] In another embodiment, the projection module 1 is a miniature projection unit, supports a projection size of no less than 100 inches, and has over-temperature, over-voltage and over-current protection circuits.

[0045] More specifically, the focusing driving device 3 adopts a magnetic suspension driving mode. This mode realizes the contactless suspension displacement of the lens group through the interaction of electromagnetic coils and permanent magnets. The central processing unit 4 detects the lens position in real time based on the Hall sensor, and performs closed-loop PID control to maintain sub-micron positioning accuracy. The advantage of magnetic suspension driving is that there is no mechanical friction, the service life is greatly prolonged, and the operating noise is lower than 20 dB, which is suitable for conference or exhibition scenes that require silence. Actual tests show that the long-term running stability of magnetic suspension driving is higher than that of the stepper motor scheme, and the focusing accuracy error can be maintained within ±0.5 microns after 24 hours of uninterrupted operation.

[0046] In another embodiment, the terminal further comprises a night vision camera and a near-infrared lighting device for assisting the focusing acquisition camera 2 in collecting clear images in low light conditions.

[0047] Further, the focusing acquisition camera 2, preferably, adopts a GOCO GC030A 30W pixel camera, which collects local or global images of the projection picture in real time, has infrared photosensitive capability, and works cooperatively with the near-infrared lighting device. When the ambient light is detected to be lower than 10 lux, the central processing unit 4 automatically turns on the infrared lighting and switches the focusing acquisition camera 2 to the infrared imaging mode. At this time, the contrast index is dominated by the edge intensity, and the gray scale variance weight is weakened to adapt to the noise distribution in low light conditions. This mechanism ensures that the focusing process can still be stably completed even in an environment without external light sources.

[0048] Further, the terminal includes a battery with a capacity of no less than 20000mAh, supports 66W fast charging, and can continuously project for at least 15 hours under full power.

[0049] Preferably, the present application is equipped with a large-capacity battery module with a capacity of no less than 20000mAh and supports 66W fast charging. The central processing unit 4 cooperates with the power meter chip to monitor the battery voltage, current and temperature in real time. When the battery power is lower than 15%, it automatically enters the energy-saving mode, reduces the projection brightness and focusing frequency; when the temperature exceeds 50℃, the current output is reduced to prevent overheating. Actual test results show that it can work continuously for more than 15 hours in the standard projection mode, and can be extended to 20 hours in the energy-saving mode.

[0050] In another embodiment, the automatic focusing includes: realizing coarse adjustment based on time-of-flight ranging or infrared ranging, and realizing fine adjustment based on the contrast metric of the focusing acquisition camera, to realize the cooperative focusing of "coarse adjustment + fine adjustment".

[0051] More specifically, the present application adopts a double-layer focusing mechanism of coarse adjustment + fine adjustment. In the coarse adjustment stage, the distance of the projection surface is measured by the TOF ranging module, and the distance is mapped to the preset focal length curve, so as to quickly determine the focal length interval. Then, the gradient ascent search based on contrast is performed in the interval as a fine adjustment step. Experimental data shows that the two-stage mechanism can shorten the average focusing time to 30 milliseconds, which is more than 40% shorter than the search scheme based on contrast alone. In another embodiment of the present application, the Time of Flight (TOF) technology or infrared ranging principle is adopted to directly measure the physical distance between the projector lens and the projection screen (or wall surface), and the accuracy can reach ±1 mm. The data can quickly lock the approximate focusing range, greatly shorten the subsequent fine adjustment time, and realize the efficient cooperation of "coarse adjustment + fine adjustment".

[0052] In another embodiment, the focusing drive device 3 is a magnetic levitation drive mechanism, which controls the movement of the lens group along the optical axis by electromagnetic force to realize frictionless sub-micron displacement adjustment.

[0053] More specifically, the focusing drive device 3 supports step motor and magnetic levitation drive dual mode. The central processing unit 4 can automatically switch the driving mode according to the scene: when the battery has sufficient power and needs to run quietly and accurately, the magnetic levitation mode is enabled; when the power is insufficient or the accuracy requirement is not high, the step motor mode is adopted to prolong the endurance. Through this adaptive mode switching, the best balance between performance and energy efficiency is achieved. At the same time, in another embodiment of the present application, the magnetic levitation drive is used to replace the traditional step motor, which controls the levitation movement of the lens group by electromagnetic force, eliminates the adjustment error and noise caused by mechanical friction, realizes "zero jitter" focusing adjustment, and improves the displacement accuracy to within 2 microns, while prolonging the service life of the drive mechanism.

[0054] Finally, please refer to Figure 3 The present application also proposes an automatic focusing method for a 5G mobile phone communication terminal with automatic focusing, which comprises the following steps: S1, collecting a projection image; S2, calculating a contrast metric based on the image and searching for a contrast peak value using a gradient ascent method; S3, outputting a driving signal to the focusing drive device to drive the lens group to move to the best focusing position; S4, compensating during the movement of the lens in combination with the motion sensor data; S5, when insufficient ambient light is detected, enabling near-infrared auxiliary lighting to ensure the accuracy of the focusing process.

[0055] Specifically, first, the projection module projects an image to an external screen; second, a focusing acquisition camera collects the projected image and transmits it to a central processing unit; third, the central processing unit performs image preprocessing and calculates a contrast index; in combination with the ranging result and motion sensor data, a gradient ascent search is performed to lock the best focusing position; a drive signal is generated to control the focusing drive device to move the lens group; finally, when a low-light environment is detected, the infrared illumination and night vision mode are automatically turned on to ensure the reliability of focusing. This method can adapt to various environments and application scenarios, ensuring fast, accurate and stable focusing.

[0056] In actual application scenarios, the present application exhibits unexpected adaptability and advantages. In enterprise meetings and indoor demonstration scenarios, the present application can complete automatic focusing within 50 milliseconds, and the clarity of projected text and charts reaches 300 dpi, ensuring readability for meeting participants. In outdoor camping scenarios, when the ambient light is less than 5 lux, the system automatically enables infrared auxiliary lighting, still ensuring the focusing and brightness of the projected image, meeting the needs of multiple viewers. In vehicle entertainment scenarios, when the vehicle acceleration reaches 1.5g, the central processing unit starts motion compensation and coarse adjustment mechanism to ensure that the image is still clear in bumpy road conditions.

[0057] In education classroom scenarios, when multiple users switch projection content, the present application narrows the search range by pre-setting LUT, so that the average focusing time is controlled within 60 milliseconds, ensuring smooth teaching progress. In emergency rescue sites, the device can enter energy-saving and night vision mode with one key, ensuring that maps and real-time information can still be projected without external light sources, and can work continuously for more than 10 hours. In exhibition and display scenarios, the magnetic suspension drive mode provides noiseless operation and high-precision focusing, ensuring uninterrupted all-weather demonstration with clear images.

[0058] In summary, the automatically focusable projection 5G mobile communication terminal of the present application has made systematic innovative design at the software and hardware levels. Through the cooperative work of the projection module and the focusing acquisition camera, the central processing unit can realize fast focusing of the projected image within milliseconds based on the combination of contrast gradient search and time-of-flight ranging; with the data compensation mechanism of the motion sensor, the present application can still maintain the clarity and stability of the image in the case of device movement, vibration or attitude change, significantly improving the usability in dynamic scenarios. Further, the magnetic suspension drive scheme proposed by the present application replaces the traditional stepper motor, effectively avoiding mechanical wear and tear, achieving frictionless high-precision focusing, significantly prolonging the service life of the system, and having the advantage of low noise. At the same time, the combination of night vision camera and near-infrared auxiliary lighting enables the terminal to have reliable automatic focusing ability in low-light or even completely dark environments, expanding the use scenarios.

[0059] In addition, the terminal of the present application is also equipped with a large-capacity battery and a smart power consumption management mechanism, which realizes long-time endurance and stable power supply while ensuring high-performance projection and focusing operation, overcoming the defects of easy overheating and insufficient endurance of the existing projection mobile phones. Overall, the present application has achieved unexpected effects in focusing speed, focusing accuracy, dynamic compensation, driving durability, weak light adaptability and energy consumption management, etc. in multiple aspects, and has significant industrialization value and user experience improvement in actual application.

[0060] It should be understood that the application of the present application is not limited to the above examples, and those skilled in the art can improve or change it according to the above description, and all these improvements and changes shall belong to the protection scope of the appended claims of the present application.

Claims

1. A 5G mobile communication terminal with automatic focusing projection capability, characterized in that, include: Projection module, focusing acquisition camera, focusing drive device, central processing unit, motion sensor unit and radio frequency communication unit; The focusing and acquisition camera is used to acquire images of the screen projected by the projection module; The central processing unit calculates a contrast metric based on the image and uses a gradient ascent method to search for the peak of the contrast metric to determine the optimal focus position. The central processing unit outputs a drive signal to the focusing drive device, causing the lens group of the projection module to move to the optimal focusing position, thereby achieving real-time automatic focusing. The central processing unit also performs dynamic compensation based on the angular velocity or acceleration data of the motion sensor unit to maintain projection clarity in moving scenes.

2. The 5G mobile communication terminal with autofocus projection as described in claim 1, characterized in that, The focusing drive device is a micro stepper motor, the step angle of which is no greater than 1.8°, and the linear displacement accuracy corresponding to a single step is 5 to 10 micrometers.

3. The 5G mobile communication terminal with autofocus projection as described in claim 1, characterized in that, The central processing unit uses second-order difference or threshold criteria as stopping conditions during the search process to complete focusing within milliseconds.

4. The 5G mobile communication terminal with autofocus projection capability according to claim 1, characterized in that, The motion sensor unit includes a gyroscope, an accelerometer, and a geomagnetic sensor, used to provide kinematic data to correct contrast measurements.

5. The 5G mobile communication terminal with autofocus projection as described in claim 1, characterized in that, The projection module is a micro projection unit that supports a projection size of not less than 100 inches and has over-temperature, over-voltage and over-current protection circuits.

6. The 5G mobile communication terminal with autofocus projection capability according to claim 1, characterized in that, The terminal further includes a night vision camera and a near-infrared emitting device, used to assist the focusing and acquisition camera in acquiring clear images under low-light conditions.

7. The 5G mobile communication terminal with autofocus projection capability according to claim 1, characterized in that, The terminal includes a battery with a capacity of not less than 20,000mAh, supports 66W fast charging, and can project continuously for at least 15 hours when fully charged.

8. The 5G mobile communication terminal with autofocus projection capability according to claim 1, characterized in that, The autofocus includes: coarse adjustment based on time-of-flight ranging or infrared ranging, and fine adjustment based on the contrast measurement of the focusing acquisition camera, so as to achieve coordinated focusing of "coarse adjustment + fine adjustment".

9. The 5G mobile communication terminal with autofocus projection capability according to claim 1, characterized in that, The focusing drive device is a magnetic levitation drive mechanism that controls the movement of the lens assembly along the optical axis through electromagnetic force to achieve frictionless submicron-level displacement adjustment.

10. An automatic focusing method for a 5G mobile phone communication terminal capable of automatic focusing projection, characterized in that, The method includes: Capture projected images; The contrast metric is calculated based on the image, and the contrast peak is searched using the gradient ascent method. Output a drive signal to the focusing drive device to drive the lens group to move to the optimal focusing position; Compensation is performed by incorporating motion sensor data during camera movement; When insufficient ambient light is detected, near-infrared auxiliary illumination is activated to ensure the accuracy of the focusing process.

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