The trend towards larger COB modules is significant, effectively reducing display seams and improving flatness.

In the wave of LED display industry upgrades towards ultra-high definition and immersive experiences, COB (Chip-on-Board) modules are ushering in a critical period of explosive growth in large-size applications. Traditional SMD packaging, limited by LED chip brackets and surface mount technology, suffers from significant seams and insufficient flatness in large-size splicing. COB, with its integrated packaging and design, achieves significantly reduced seams and a leap forward in overall screen flatness through innovative large-size module structures and precision manufacturing processes, becoming the optimal solution for ultra-large screens and ultra-large area displays, typically around 100 inches. From 2025 to 2026, COB large-size modules will transition from high-end customization to standardized mass production, with market penetration rapidly increasing, reshaping the product form and application boundaries of the display industry.

I. Core Breakthrough in Large-Size Design: From Structure to Process, a Dual-Driven Approach to Reduce Gaps and Improve Flatness

The large-size COB module is not simply about enlarging the substrate size, but rather a systematic solution to the challenges of seam and flatness in large-size scenarios through a three-pronged approach of structural reconstruction, process optimization, and material upgrades. This achieves an experience upgrade from "partial perfection" to "global uniformity."

1. Large-Size Module Design: Directly Reducing the Number of Seams, Eliminating Visual Interference at the Source

Traditional small-size modules (such as 300×168.75mm) result in dense seams in large-size screens, creating a strong sense of horizontal segmentation. Since 2025, the industry has introduced innovative solutions such as the 150×337.5mm vertical large module, halving the width of a single module and directly reducing the number of horizontal seams by approximately 50%. Taking a 135-inch screen with a 16:9 aspect ratio as an example, a small module solution requires 12 horizontally spliced ​​units, while a large module only requires 6. This significantly reduces the sense of screen fragmentation and greatly improves the continuity of dynamic videos and panoramic images. Simultaneously, the large-size module is compatible with the 600mm universal cabinet standard, achieving standardized compatibility and balancing large-scale production with engineering delivery efficiency.

2. Precision Manufacturing Process: Overcoming the Core Bottleneck of Large-Size Flatness

Large-size modules are prone to "concave" deformation due to insufficient structural rigidity, affecting display consistency. The industry has solved this problem through two major technological breakthroughs:

High-rigidity structural design: Adopting a 2.25:1 aspect ratio vertical module improves structural strength, effectively suppresses micro-concavity in the center of the module, and controls the overall screen flatness tolerance to **≤0.1mm**, far exceeding the industry standard, completely eliminating "wavy" appearance and image distortion.

High-precision packaging and calibration: COB full-board potting encapsulation combined with a nano-anti-glare coating achieves pixel-level optical uniformity; before leaving the factory, full-screen 32-point color consistency calibration is performed, with a ΔE color accuracy value < 1.5 and a full-screen color deviation Δu'v' < 0.003, ensuring seamless color and brightness across the entire large-size screen.

3. Material and technology synergy: Enhanced performance support

High thermal conductivity substrate: Utilizing aluminum nitride ceramic or high thermal conductivity aluminum substrates, the heat dissipation path is shortened, reducing thermal resistance to below 4.8K/W, suppressing localized thermal expansion and deformation of the large-size screen, and ensuring long-term operational stability.

Flip-chip common cathode drive: The flip-chip process eliminates gold wire interference, and the common cathode drive independently adjusts the voltage of the RGB chips, reducing light decay and color shift. Combined with HDR high dynamic range processing, it improves image detail while reducing seams.

II. Prominent Scenario Value: Large-Size COB Modules Reshape the High-End Display Landscape

The core value of large-size COB modules lies in their precise matching of the experience needs of ultra-large screens and ultra-large area scenarios. This creates a differentiated barrier in high-end commercial, professional-grade display, and immersive consumer applications, driving the shift from high-end customization to large-scale adoption.

1. High-End Commercial Display: Core Solution for Command Centers and Conference Scenarios

Command Centers/Monitoring and Dispatch: Ultra-large area COB screens (over 500㎡ per unit) achieve seamless splicing across the entire area. Commanders can quickly capture overall information. Splicing gaps are <0.2mm, virtually invisible visually, making them standard equipment in core command scenarios such as military, transportation, and energy.

High-End Conferences/Corporate Showrooms: 100-inch integrated COB conference all-in-one machines (108-inch, 135-inch, 163-inch) replace traditional multi-screen splicing, achieving an immersive visual experience. By 2025, COB penetration in this scenario exceeded 40%, becoming the mainstream choice for high-end conference rooms.

2. Professional-Grade Display: Image Quality Guarantee for Broadcasting and XR Shooting

Broadcasting Studios: Large-size COB screens, without LED bracket obstructions, offer excellent optical uniformity, meeting the color and detail reproduction requirements of 4K/8K ultra-high-definition live broadcasts, making them core equipment in high-end studios.

XR Virtual Shooting: The high flatness and low reflectivity of COB screens are well-suited for virtual shooting scenarios, eliminating noticeable seams and light/shadow breaks, supporting realistic blending of virtual and real scenes. Shipments of large-size COB modules in the XR field are projected to increase by over 60% year-on-year in 2025-2026.

3. Consumer and Cultural Tourism Scenarios: Penetration from High-End to Mass Market

High-End Home Theaters: 100-inch COB giant screens (such as 135-inch products priced below 200,000 RMB) are replacing laser TVs and projectors, rapidly entering the high-net-worth family market with their high brightness, high contrast, and burn-in-free advantages.

Cultural and Tourism Commercial Complexes: Irregularly shaped and curved large-size COB screens create an immersive light and shadow experience, combined with high protection features suitable for semi-outdoor scenarios, becoming an innovative display carrier for commercial landmarks and cultural and tourism projects.

III. Market and Trends: Accelerated Penetration of Large-Size Displays Defines Future Display Standards

The trend of large-size COB modules is transforming from a "technological trend" to a "market mainstream," leading to a dual restructuring of the industry landscape and application scenarios. The next three years will see a period of rapid growth.

1. Rapid Increase in Market Size and Penetration Rate

The global COB display terminal market size reached 10.17 billion yuan in 2025, with large-size modules (single-piece area ≥ 0.5㎡) accounting for over 35%. DISCIEN data shows that in the first quarter of 2025, COB technology accounted for 23.6% of sales in the small-pitch & micro-pitch market, with large-size scenarios showing significantly higher growth rates than the overall market. The market size of large-size COB modules is projected to grow by over 55% year-on-year in 2026-2027, exceeding 12 billion yuan globally by 2029, becoming the core growth engine of the COB industry.

2. Clear Industry Trends: Standardization, Integration, and Globalization

Module Standardization: Large-size specifications such as 150×337.5mm are becoming mainstream, driving large-scale production and cost reduction. The overall cost of large-size COB modules is expected to decrease by over 40% in 2026 compared to 2024.

Product Integration: Upgrading from "module + enclosure" to "integrated whole machine," integrating control systems, power supplies, and audio components to achieve plug-and-play functionality and shorten installation and debugging cycles by over 30%.

Deepening Technological Integration: The integration of COB with quantum dot and glass-based technologies has achieved a luminous efficacy exceeding 220lm/W, further improving the color and energy-saving performance of large-size screens and adapting to more high-end application scenarios.

3. Competitive Landscape: Chinese Companies Dominate the Global Large-Size COB Market

As the core of the global COB industry, China, leveraging its advantages across the entire industry chain (domestic production of upstream substrates and phosphors, automated packaging equipment in the midstream, and application scenarios in the downstream), holds over 65% of the global large-size COB market share. Leading companies (such as Zhongqi Optoelectronics, Hangxian Optoelectronics, and Maixinwei) consolidate their market dominance through technological innovation and capacity expansion in large-size modules, while accelerating penetration into Southeast Asia, Europe, and the United States, with overseas exports growing at over 45%.

Conclusion

The deepening trend of large-size COB modules is essentially an inevitable choice for the display industry seeking ultimate visual experience and efficient scenario adaptation. By reducing seams and improving flatness, large-size COB modules completely break the traditional limitations of display scenarios, reshaping the form and value of display products from high-end command and professional broadcasting to home theaters and cultural tourism and commerce. In 2026 and beyond, with the advancement of standardization, continuous cost reduction, and accelerated technological iteration, COB large-size modules will become the core form of small-pitch & micro-pitch displays, propelling the LED industry into a new stage of "full-domain high-definition and seamless integration".