Automotive Rearview Mirror FPC

Automotive rearview mirror FPC is a core segmented category of flexible printed circuits, specially used for signal transmission and connection of automotive rearview mirror systems, and is the "nerve center" between the rearview mirror and core components such as automotive electronic control unit (ECU), power supply system, sensors (such as angle sensors, light sensors), and actuators (such as adjustment motors, heating sheets). Compared with traditional rigid printed circuit boards (PCBs), automotive rearview mirror FPC has the core advantages of bendability, foldability, thinness, light weight and dense wiring, which can accurately adapt to the narrow and special-shaped installation space inside the automotive rearview mirror, flexibly fit the arc structure of the rearview mirror shell and the movement track of rotating components, effectively save internal space, simplify the assembly process of the rearview mirror, improve production efficiency, and reduce the overall weight of the rearview mirror, helping automobiles save energy and reduce consumption.

As one of the first enterprises in China to layout the flexible electronics industry, Honflex Electronics has become a core supplier in the field of automotive rearview mirror FPC, serving many mainstream domestic and foreign automakers and automotive electronics Tier1 suppliers, relying on nearly 20 years of FPC R&D and production experience. The company's automotive rearview mirror FPC products cover various types such as single-sided boards, double-sided boards, multi-layer boards and rigid-flex boards. According to the customer's rearview mirror design scheme and functional requirements, it can customize products of different specifications and performances, fully adapting to the needs of various rearview mirrors of fuel vehicles and new energy vehicles (pure electric, hybrid), covering entry-level, mid-range, high-end and other full-scenario models, and realizing the "one-stop" flexible circuit solution supply from product design, sample proofing, mass production to after-sales service.

Core Structural Characteristics

Based on the installation environment and functional requirements of automotive rearview mirrors (needing to withstand frequent rotation, alternating high and low temperatures outdoors, erosion of wind, rain and sand for a long time, and having extremely high requirements for signal transmission accuracy and mechanical stability), Honflex Electronics' automotive rearview mirror FPC products have been targeted optimized in structural design, taking into account flexibility, reliability and signal stability. All structural designs have been repeatedly verified by Honflex Electronics' laboratory to adapt to long-term on-board use scenarios. The core structural characteristics are as follows:

1. Substrate Selection: High-end Flexible Substrate, Balancing Flexibility and Durability

The core substrate of the product adopts imported or domestic high-end polyimide (PI) substrate with a thickness range of 0.025mm-0.1mm. Compared with ordinary PI substrates, it has better flexibility, heat resistance, mechanical strength and insulation performance. The PI substrate itself has good chemical corrosion resistance and weather resistance, which can effectively resist the erosion of rainwater, sand and dust, oil stains, ultraviolet rays, etc. in the on-board outdoor environment, avoiding substrate aging, embrittlement and cracking; its bending times can reach more than 100,000 times, and the minimum bending radius can reach 0.5mm, which can flexibly adapt to the frequent bending needs of the rotating components of the rearview mirror, and will not cause substrate fracture or signal interruption due to long-term repeated rotation. In addition, the surface of the substrate has been specially passivated, which greatly improves the bonding force between the copper foil and the substrate, effectively avoiding problems such as copper foil falling off and delamination under the on-board vibration and rotation environment, and extending the service life of the product. Honflex Electronics selects high-quality substrate suppliers through a strict substrate procurement control system, establishes a supplier evaluation mechanism, and ensures that each batch of substrates meets the automotive industry ISO/TS 16949 quality system standard.

2. Copper Foil Structure: Precision Copper Foil, Ensuring Signal Transmission Accuracy

Electrolytic copper foil or rolled copper foil is used, with a thickness range of 12μm-70μm, which can be flexibly selected according to the rearview mirror signal transmission needs (such as motor adjustment signals, heating control signals, imaging signals, etc.). Among them, high-end intelligent rearview mirror FPC products adopt rolled copper foil, which has finer grains, better conductivity and lower resistance, which can effectively reduce high-frequency signal transmission loss, ensure real-time and accurate transmission of high-frequency signals such as rearview mirror imaging and anti-glare, and avoid problems such as blurred imaging and delayed anti-glare response; ordinary electric adjustable rearview mirror FPC adopts high-quality electrolytic copper foil, balancing performance and cost-effectiveness, meeting basic signal transmission needs. The copper foil adopts the precision etching process independently developed by Honflex Electronics, and the minimum line width and line spacing can reach 0.03mm/0.03mm, which can realize a denser circuit layout, integrate more signal interfaces in a limited space, and adapt to the development trend of rearview mirror integration and multi-function (such as integrating cameras, turn signals, welcome lights and other functions). Relying on advanced etching equipment, Honflex Electronics can ensure the precision and consistency of copper foil lines, with errors controlled within ±5μm, greatly improving the signal transmission stability of products.

3. Cover Layer Design: Double Protection, Improving Environmental Adaptability

The surface of the product is provided with two layers of protective structures, namely Cover Lay and Solder Mask. The double protection greatly improves the environmental adaptability and reliability of the product, adapting to the harsh outdoor on-board environment. The cover film adopts a flexible PI cover film, which is accurately attached to the surface of the copper foil circuit to play the role of insulation, wear resistance, oxidation resistance and water vapor resistance, and does not affect the flexibility of the product, ensuring that the product can smoothly fit the special-shaped structure and rotating components inside the rearview mirror; the solder mask adopts high-end solder mask ink with high temperature resistance, wear resistance, chemical corrosion resistance and UV resistance, which is printed on the surface of the cover film to further improve the product's resistance to high and low temperature impact, vibration, dust and water, and can effectively resist the impact of high and low temperature changes, wind, rain, sand and dust, UV irradiation, etc. in the on-board outdoor environment, protect the circuit from damage, and avoid short circuit, signal interruption and other faults. In addition, for the interface part of the rearview mirror FPC (the part connected to the ECU, sensor, and actuator), a reinforcing plate design is adopted to improve the mechanical strength of the interface, avoid interface deformation and line breakage during plugging and unplugging, and ensure the stability of the connection. Honflex Electronics' cover layer lamination process adopts high-temperature lamination technology to ensure the close fit between the cover film, copper foil and substrate, without bubbles or peeling, further improving the reliability of the product.

4. Special-shaped Structure Customization: Adapting to the Complex Installation Space and Rotation Needs of Rearview Mirrors

The internal space of the automotive rearview mirror is small and the structure is complex. The rearview mirror design schemes of different models are quite different, and it is necessary to adapt to the movement track of the rotating components, so the requirements for the shape, bending angle, size, bending life, etc. of the FPC are different. Honflex Electronics has strong customization capabilities for special-shaped structures, and can customize special-shaped FPC products of different shapes, bending angles and sizes according to the rearview mirror drawings, installation space dimensions, rotation angles and functional requirements provided by customers. The product can realize multi-dimensional bending and folding, can accurately fit the installation position of the rearview mirror shell, display module and motor, pass through narrow installation gaps, effectively utilize the idle space inside the rearview mirror, simplify the overall assembly structure of the rearview mirror, and reduce the assembly difficulty. At the same time, in the process of special-shaped structure design, Honflex Electronics' R&D team will conduct stress analysis and fatigue testing, optimize the circuit layout and the structure of the bending part, avoid problems such as circuit crowding and stress concentration in the bending part, and ensure that the product will not be damaged due to bending fatigue during long-term frequent rotation. Up to now, the company has completed the customization of hundreds of special-shaped automotive rearview mirror FPC products, adapting to the rearview mirror design needs of different automakers, and accumulating rich customization experience.

5. Reinforced Structure Design: Adapting to Frequent Rotation Scenarios

Aiming at the core scenario of frequent rotation of automotive rearview mirrors (the daily rotation times can reach dozens of times, and the cumulative rotation times can reach tens of thousands of times in long-term use), Honflex Electronics has carried out reinforced design on the key parts of the automotive rearview mirror FPC products, further improving the mechanical stability and service life of the products. In the bending and rotating parts of the FPC, a design of locally thickened substrate or additional reinforcing tape is adopted to disperse the stress generated during rotation, avoiding the line breaking and falling off due to long-term stress; in the connection part between the FPC and the motor and sensor, an integrated connection design is adopted to reduce the connection nodes and reduce the risk of node loosening and poor contact during rotation; at the same time, the circuit layout is optimized to avoid the lines vulnerable to stress from the bending center, ensuring the integrity of the lines and the stability of signal transmission during rotation. These reinforced designs have undergone long-term fatigue tests in Honflex Electronics' laboratory to ensure that the product can adapt to the rotation needs of the entire life cycle of the automotive rearview mirror, and the failure rate is controlled at an extremely low level.

Main Performance Advantages

Relying on Honflex Electronics' R&D strength, advanced production technology and strict quality control, the company's automotive rearview mirror FPC products are comprehensively superior to the industry average in performance. Aiming at the special use scenarios of automotive rearview mirrors (frequent rotation, harsh outdoor environment, multi-signal collaborative transmission), it focuses on core advantages such as high reliability, high signal stability and high environmental adaptability, while taking into account lightweight, thinness and customization, as follows:

1. High Reliability, Adapting to Long-term and Frequent On-board Use Needs

The product has passed strict reliability tests, fully complying with the automotive industry ISO/TS 16949 quality system standard and AEC-Q200 (passive component reliability test standard), and can withstand various harsh tests in the on-board environment. The service life can reach more than 15 years, which is synchronized with the service life of the entire vehicle. The specific performance is as follows: in the vibration test, it can withstand the vibration environment of 10-2000Hz and acceleration of 10G, without line breakage or signal interruption, adapting to various vibration scenarios during vehicle driving (such as bumpy roads, engine vibration), avoiding abnormal rearview mirror functions caused by vibration; in the impact test, it can withstand the impact force of 50G, which can resist the impact caused by sudden situations such as vehicle collision and emergency braking, ensuring that the product will not be damaged by impact; in the fatigue test, it can achieve more than 100,000 repeated bendings, and the product performance has no obvious attenuation after bending, which can long-term adapt to the frequent rotation state of the rearview mirror; in the lead-free soldering test, the soldered interface has high strength and stable conductivity, avoiding poor contact, signal interruption and other faults caused by poor soldering; in the rotation durability test, after 50,000 repeated rotations, the product can still maintain stable signal transmission and mechanical performance without any faults. Honflex Electronics has established a complete reliability test system, and each product must go through multiple rounds of reliability tests (vibration test, impact test, fatigue test, high and low temperature test, etc.) before leaving the factory, and unqualified products are resolutely not allowed to leave the factory to ensure stable product quality.

2. High Signal Stability, Ensuring Accurate Realization of Various Rearview Mirror Functions

The signal transmission quality of the automotive rearview mirror directly affects the stability and accuracy of functions such as adjustment, heating, imaging, and anti-glare, which is related to driving safety. Honflex Electronics' automotive rearview mirror FPC achieves high signal stability through optimized circuit design, adoption of high-end materials and precision processes, effectively avoiding signal delay, transmission error, signal interruption and other problems. The product has low signal transmission loss. At 1GHz frequency, the signal attenuation is ≤0.5dB/cm, which can effectively ensure the stable transmission of high-frequency signals such as motor adjustment, heating control and imaging, ensuring precise rearview mirror adjustment, uniform heating and clear imaging; at the same time, the product has excellent electromagnetic compatibility (EMC), passed EMI (Electromagnetic Interference) and EMS (Electromagnetic Susceptibility) tests, which can effectively resist electromagnetic interference in the on-board environment (such as electromagnetic signals generated by engines, air conditioners, radars and other equipment), and will not generate electromagnetic interference itself, affecting the normal operation of other automotive electronic equipment; in addition, the product adopts impedance matching design, and the impedance deviation is controlled within ±10%, which further improves the stability and consistency of signal transmission, ensuring stable realization of various rearview mirror functions under different working conditions. Honflex Electronics' R&D team continuously optimizes the circuit layout through simulation and actual testing, reduces signal interference, and ensures the stability of signal transmission.

3. High Environmental Adaptability, Resisting Harsh Outdoor On-board Environment

Automotive rearview mirrors are exposed to the outdoors for a long time, and the environment where they are located is complex and changeable, facing various tests such as alternating high and low temperatures, humidity changes, wind, rain, sand and dust, oil stains, UV irradiation, etc., which has extremely high requirements for the environmental adaptability of the FPC. Honflex Electronics' automotive rearview mirror FPC has excellent environmental adaptability and can work stably in various harsh environments: the working temperature range is -40℃~125℃, which can work normally in extremely cold (such as northern winter, temperature as low as -40℃) and extremely hot (such as southern summer exposure, rearview mirror surface temperature as high as 120℃ above) environments, without problems such as substrate embrittlement, line oxidation, and signal abnormality; the storage temperature range is -55℃~150℃, which can adapt to the storage and transportation environments in different regions, avoiding product damage caused by improper storage and transportation environment; in terms of moisture resistance, it can work continuously for 1000 hours in an environment with relative humidity of 85% (40℃), with no obvious change in performance, and can resist the erosion of outdoor rainwater and water vapor; in terms of chemical corrosion resistance, it can resist the erosion of on-board oil stains, rainwater, detergents and other chemical substances, and will not have problems such as substrate expansion and line short circuit; in terms of UV resistance, after long-term UV irradiation test, the product has no aging, discoloration, performance attenuation and other phenomena, and can adapt to long-term outdoor use; in addition, the product has waterproof and dustproof performance, passed the IP65 protection level test, which can effectively prevent dust and rainwater from entering the circuit, ensuring long-term stable operation of the product. Honflex Electronics conducts long-term aging tests on products by simulating different on-board outdoor environments to ensure that products can work stably in various harsh environments.

4. Lightweight and Thin, Helping Automobile Energy Saving and Consumption Reduction and Assembly Optimization

With the development of the automotive industry towards lightweight and energy-saving, the demand for lightweight on-board electronic components is becoming increasingly urgent. As one of the core external on-board components, the lightweight of the automotive rearview mirror is of great significance to the overall energy saving and consumption reduction of the automobile and driving stability. Honflex Electronics' automotive rearview mirror FPC products adopt thin substrate and precision structure design, and the overall thickness of the product can be controlled between 0.1mm-0.3mm. Compared with traditional rigid PCB, the weight is reduced by more than 60%, which can effectively reduce the overall weight of the automotive rearview mirror, thereby reducing the overall weight of the automobile, helping the automobile save energy and reduce consumption (for every 10kg reduction in vehicle weight, the fuel consumption per 100 kilometers can be reduced by 0.05-0.1L). At the same time, the thin and lightweight design can further save the internal space of the rearview mirror, providing more possibilities for the miniaturization and integration design of the rearview mirror. For example, it can realize the integrated design of the rearview mirror with cameras, turn signals and welcome lights, improving the sense of technology and aesthetics of the automobile appearance; in addition, the lightweight design of the product can also reduce the wind resistance and vibration load during vehicle driving, reduce the loss of the product caused by vibration and wind resistance, further improve the service life and reliability of the product, and simplify the assembly process of the rearview mirror, improving assembly efficiency. On the premise of ensuring product performance, Honflex Electronics continuously optimizes the product structure to maximize the lightweight and thinness of the product.

5. Strong Customization Capability, Adapting to Diversified Rearview Mirror Needs

The rearview mirror design schemes of different automakers and models are quite different, and the functional requirements are also different (such as ordinary electric adjustment, heating, anti-glare, 360° imaging, automatic folding, etc.), so the requirements for the specifications, performance, structure, etc. of the FPC are different. Honflex Electronics has complete customized R&D and production capabilities, and can provide full-process customized services from product design, sample proofing, mass production to after-sales service according to the specific needs of customers. Customers can customize FPC products of different specifications (line width and line spacing, thickness, size), different performances (signal transmission rate, environmental adaptability, bending life), and different structures (special-shaped, multi-layer, rigid-flex combination) according to the design needs of their own rearview mirrors; for high-end intelligent rearview mirrors of high-end models, high-end FPC products with high-density lines, low signal loss and high reliability can be customized to meet the needs of high-definition imaging and multi-function integration; for ordinary electric rearview mirrors of entry-level models, cost-effective FPC products can be customized to balance performance and cost. The company has a professional R&D and design team, which can quickly respond to customer needs, complete product design and simulation analysis. The sample proofing cycle is short (samples can be delivered in as fast as 3 days), and the mass production cycle can be controlled within 7-15 days, which can meet the customer's rapid mass production needs. Up to now, the company has provided customized automotive rearview mirror FPC products for many mainstream domestic and foreign automakers, accumulating rich customized experience.

Key Technical Parameters

The key technical parameters of Honflex Electronics' automotive rearview mirror FPC products strictly follow the automotive industry standards, balancing performance and practicality, and fully adapt to the signal transmission and installation needs of automotive rearview mirrors. The parameters are optimized according to the characteristics of frequent rotation of rearview mirrors and outdoor environment use. The parameters of products with different specifications can be customized according to customer needs. The core general parameters are as follows:

Application Scenarios

With excellent performance, strong customization capabilities and Honflex Electronics' brand strength, Honflex Electronics' automotive rearview mirror FPC products are widely used in rearview mirror systems of various types of vehicles, including fuel vehicles and new energy vehicles (pure electric, hybrid), adapting to entry-level, mid-range, high-end and other full-scenario models, covering various types such as traditional manual rearview mirrors, electric adjustable rearview mirrors, and intelligent rearview mirrors. All application scenarios have achieved mass supply and have been highly recognized by customers. The specific application scenarios are as follows:

1. Traditional Manual Rearview Mirror

Traditional manual rearview mirrors are mainly used in entry-level fuel vehicles and some commercial vehicles. Their core function is to provide the driver with a rear view, with a relatively simple structure. The performance requirements for FPC focus on reliability and cost-effectiveness, mainly used to connect the basic electronic components (such as small lights) inside the rearview mirror. Aiming at the needs of traditional manual rearview mirrors, Honflex Electronics has customized cost-effective automotive rearview mirror FPC products, adopting high-quality electrolytic copper foil and PI substrate, balancing signal transmission stability and cost control, which can realize the signal transmission of basic electronic components inside the manual rearview mirror, ensuring the normal realization of basic functions. The product has excellent anti-vibration and high and low temperature resistance, can adapt to the use environment of commercial vehicles and entry-level fuel vehicles (such as bumpy roads, long-term outdoor exposure), has a long service life and low failure rate. At present, the company's traditional manual rearview mirror FPC products have been mass-applied to entry-level models and commercial vehicles of many domestic mainstream automakers, and have been widely recognized by customers with stable quality and high cost-effectiveness.

2. Electric Adjustable Rearview Mirror

Electric adjustable rearview mirrors are the mainstream configuration of current mid-range models. Compared with traditional manual rearview mirrors, they have functions such as electric angle adjustment, electric folding, heating and defogging, which have higher requirements for the signal transmission stability and mechanical stability of FPC. They need to realize the stable transmission of motor adjustment signals and heating control signals, and adapt to the folding and rotating needs of rearview mirrors. Aiming at the needs of electric adjustable rearview mirrors, Honflex Electronics has optimized the product's circuit design and reinforced structure, adopted precision etching process to achieve a denser circuit layout, which can adapt to the multi-signal transmission needs of electric