Understanding LED Display Scan Modes: How Does 1/4 Scan vs. 1/8 Scan Impact Display Performance?
When selecting and configuring an LED display, parameters like pixel pitch, brightness, and refresh rate are often top of mind. However, the scan mode is another crucial technical specification that should not be overlooked. It directly affects display brightness, refresh stability, power load distribution, and the overall cost structure of the screen system.
The scan mode refers to how the LED driver IC controls the row-column signals within a module. For example, in a 1/4 scan, every 4 rows of LED pixels share a single set of driving circuits, with each group being lit sequentially during one refresh cycle. In contrast, a 1/8 scan means that 8 rows share the same driver resources, with more rows lit in a time-multiplexed manner.
From a technical standpoint, the larger the scan ratio (such as 1/8 or 1/16), the shorter the duration each row is illuminated within a unit of time. As a result, the overall screen brightness tends to decrease. Therefore, under the same voltage conditions, a 1/4 scan typically offers higher brightness compared to a 1/8 scan. However, 1/8 scan designs generally require fewer driver ICs and simpler wiring, leading to lower overall hardware costs.
This article will further explore the structural differences, driving logic, performance characteristics, and applicable scenarios of 1/4 scan versus 1/8 scan technologies. The goal is to help LED display buyers make more informed and balanced technical decisions between performance and cost.
Table of Contents
Toggle1. What Is the Scan Mode in an LED Display?
The scan mode in an LED display refers to the method by which the driver IC lights up the LED pixels through a combination of row and column control using time-division multiplexing logic during the display control process. It determines how many rows of pixels are lit at any given moment and is one of the core control parameters in LED display technology.
Modern LED displays often contain tens of thousands—or even hundreds of thousands—of LED lamps. If each individual pixel were driven by its own dedicated circuit, the result would be prohibitively expensive, with highly complex circuitry and significantly increased power consumption. To strike a balance between performance and cost, the industry widely adopts row-column scanning, also known as dynamic scanning.
Why Use Scan Mode Instead of Point-by-Point Control?
The main reasons for using scan mode are:
To reduce the number of driver ICs: A single IC controls multiple rows of LEDs, significantly cutting hardware costs.
To simplify PCB routing: It avoids the complexity and high cost associated with point-to-point wiring and multi-layer board design.
To lower power consumption and ease thermal management: Time-division lighting distributes peak current loads, improving overall thermal performance.
How Scan Mode Works
The essence of scan mode is time-division multiplexing, where not all pixels are lit simultaneously within a full image refresh cycle. Instead, pixel rows are activated in sequence based on predefined groupings. For example:
In a 1/4 scan, the module is divided into four row groups. The driver IC controls one group at a time in each refresh cycle, meaning only 1/4 of the rows are lit at any given moment.
In a 1/8 scan, the module is divided into eight row groups, and 1/8 of the rows are lit sequentially until a full refresh cycle is completed.
Because scanning frequencies typically operate in the hundreds or even thousands of hertz, the human eye cannot detect the rapid switching. As a result, the displayed image appears continuous and stable.
Static Drive vs. Dynamic Scan
Drive Type | Description | Advantages | Disadvantages |
---|---|---|---|
Static Drive | Each pixel has a dedicated signal and is continuously lit | High brightness, excellent stability, precise grayscale | High cost, more hardware complexity |
Dynamic Scan (e.g., 1/4, 1/8) | Multiple pixels share driver channels and are lit sequentially | Lower cost, simplified structure, energy-efficient | Slightly lower brightness, more complex control logic |
2. 1/4 Scan vs. 1/8 Scan: Detailed Comparison of Technical Parameters and Structural Differences
The choice of driving method in an LED display directly impacts brightness, refresh rate, hardware architecture, and overall cost control. Below is a comprehensive comparison between 1/4 scan and 1/8 scan in terms of key technical parameters and structural design:
Aspect | 1/4 Scan | 1/8 Scan |
---|---|---|
Driving Method | Lights up 1/4 of the LED rows in the module at a time. Completes one full refresh in 4 cycles. | Lights up 1/8 of the LED rows at a time. Completes one full refresh in 8 cycles. |
Refresh Speed | Relatively slower: More LEDs are driven simultaneously, resulting in higher data load and processing pressure. | Relatively faster: Fewer LEDs are lit per cycle, enabling quicker data transfer and lighter driver load. |
Display Brightness | Higher: Longer illumination time per row contributes to greater screen stability and higher brightness output. | Slightly lower: Each pixel remains lit for a shorter time, resulting in comparatively lower overall brightness. |
Cost Structure | Lower: Requires fewer driver ICs, simpler PCB routing, ideal for budget-sensitive projects. | Slightly higher: Requires more driver chips and complex wiring to achieve faster scan rates. |
Typical Applications | Suitable for basic indoor LED displays, budget-friendly fine-pitch screens, and text-based information boards. | Commonly used in high-brightness outdoor displays, large stage screens, sports venues, and traffic guidance signs where brightness and refresh rate are critical. |
When comparing scan modes, don’t just focus on the scan ratio. You should also consider factors such as pixel density, intended application, and target brightness.
If the project has a tight budget and moderate image quality requirements, 1/4 scan offers better cost-performance.
If the display requires high refresh rates, camera flicker resistance, or will operate in bright outdoor environments, 1/8 scan or even 1/16 scan is strongly recommended.
3. How Does Scan Mode Affect Display Performance?
In practical applications, the scan mode of an LED display is more than just an electrical design parameter—it directly influences image refresh behavior, brightness output, operational stability, and even the overall system lifespan. Below is a detailed explanation from three critical dimensions:
1. Refresh Rate and Flicker Performance
Refresh rate refers to the number of times per second the display updates its image. It’s a vital metric for screen stability, motion handling, and compatibility with cameras or recording equipment.
With 1/8 scan, only 1/8 of the LED rows are activated at any given time. This smaller data load allows for faster data processing and quicker switching cycles, making it easier to achieve high refresh rates such as 3840Hz or even 7680Hz.
This is especially important in scenarios like live broadcasting, stage performances, and high-speed filming, where image stability is crucial. A higher refresh rate helps eliminate visual artifacts like scan lines, flickering, or ghosting.
In comparison, 1/4 scan must light up more rows at once under the same driving conditions. This places a heavier load on the system, which may slightly compromise refresh performance—posing a risk of flicker in environments that require strict camera compatibility.
2. Brightness Performance
In LED displays, brightness is not only a function of driving current but also closely tied to the effective illumination time per LED.
Under the same driving current and duty cycle, 1/4 scan allows each LED to remain on longer within a given time window, which generally results in higher perceived brightness. This is advantageous in environments that demand strong visual impact—such as shopping malls, transit hubs, and indoor advertising spaces.
While 1/8 scan provides a shorter illumination time per LED, it can compensate for brightness by increasing the drive current or optimizing PWM dimming algorithms. In practice, well-optimized 1/8 scan systems can achieve brightness levels comparable to or equal to those of 1/4 scan displays.
3. Operational Stability and System Lifespan
During prolonged operation, heat buildup and IC load are key factors affecting the stability and longevity of LED displays.
In 1/4 scan, more LEDs are lit simultaneously, which increases the instantaneous current demand on both the driver IC and the power supply. This leads to faster heat accumulation. If cooling is insufficient, it can cause reduced stability and accelerated LED degradation due to thermal stress.
Conversely, 1/8 scan distributes the load more evenly, even though the ICs operate at higher switching frequencies. The thermal distribution is more balanced, helping to keep the display’s operating temperature within optimal ranges. This contributes to better system reliability and longer lifespan.
4. How to Choose the Right Scan Mode Based on Project Requirements
Different application scenarios place varying demands on LED display performance—factors such as brightness, refresh rate, camera compatibility, and budget all influence the choice of scan mode. Below is a comparative guide to help determine the most suitable scan mode for common use cases:
Application Type | Recommended Scan Mode | Rationale |
---|---|---|
Indoor Meetings / Showrooms | 1/4 or 1/8 | For budget-conscious projects featuring mainly text or static graphics under soft ambient lighting, 1/4 scan is typically sufficient. If the project requires enhanced image detail, smooth motion playback, or better photo/video compatibility, 1/8 scan is preferable. |
Stage Performances / Film Shoots | 1/8 Scan | Environments involving filming or live production demand very high refresh rates to avoid scan lines or flickering on camera. 1/8 scan enables easier achievement of ≥3840Hz refresh rates, ensuring clear and stable image performance under professional lenses. |
Outdoor Advertising Displays | 1/8 Scan | Outdoor environments require high brightness, stability, and robust thermal management. Combined with high-brightness LEDs and current compensation, 1/8 scan delivers stable long-term performance that withstands direct sunlight and 24/7 operation. |
Churches / Rental LED Screens | 1/8 Scan | Many church or rental displays involve mobile setups, temporary installations, and variable lighting conditions. 1/8 scan offers better adaptability, higher image quality, and is suitable for displaying text, visuals, and video content—enhancing the on-site visual experience. |
Information Boards / Price Displays | 1/4 Scan | These applications typically prioritize cost-efficiency, with mostly static numeric or text-based content. 1/4 scan is sufficient and provides excellent value for use in supermarkets, bus stops, or directional signage. |
For live-streamed events, camera shooting, or close viewing distance, prioritize 1/8 scan for high refresh performance.
For price-sensitive projects without complex video content, 1/4 scan offers substantial cost savings.
Always match the scan mode with the supported configuration of the LED module, including the control system, LED type, and environmental conditions for a fully optimized solution.
5. Common Misconceptions and Purchasing Tips: Avoiding Pitfalls in Scan Mode Selection
In real-world LED display procurement or system integration projects, scan mode is often underestimated—or even overlooked. However, it directly impacts image quality, system refresh performance, stability, and overall compatibility. Below are the most common misconceptions and practical recommendations for buyers, integrators, and decision-makers:
Misconception 1: A Higher Scan Ratio Is Always Better
Many assume that higher scan ratios (e.g., 1/8, 1/16) automatically mean better image quality or more advanced systems. In reality, selecting the scan ratio should be based on a balanced evaluation of budget, application type, brightness requirements, and camera compatibility.
Higher scan ratios support better refresh performance and smoother image rendering, ideal for stages, filming environments, or control centers with strict dynamic visual demands.
Lower scan ratios offer advantages in brightness, energy efficiency, and cost control, making them suitable for signage, commercial displays, or basic rental use cases.
▶ Recommendation: Choose based on the actual application—not simply “the higher, the better.”
Misconception 2: Low Refresh Rate Doesn’t Impact Viewing
While low refresh rates may appear acceptable to the naked eye, they become a major issue in mobile filming, livestreaming, or event recording, where visible “scan lines,” flicker, or moiré patterns can occur.
▶ Recommendation: For any camera-involved setup, use LED modules with ≥1920Hz refresh rate. For livestreaming or professional staging, ≥3840Hz is recommended to ensure a clean, stable image on camera.
Misconception 3: Module Refresh Rate Equals Full Screen Refresh Rate
Some buyers mistakenly believe that if a module supports high refresh, the entire screen will perform accordingly. In fact, actual system performance also depends on the sending card processing power, receiver bandwidth, and signal cable quality.
▶ Recommendation: When evaluating refresh capability, consider not only module specs but also whether the sending cards, receiving cards, and power supplies are properly matched. Always request a live demo to verify visual performance.
Misconception 4: Scan Mode Can Be Freely Changed
In late project stages or after budget revisions, some users attempt to switch from a 1/8 scan module to 1/4 (or vice versa) to save costs or improve performance. However, scan modes involve different circuit layouts, driver logic, and firmware configurations. Improper swapping can cause display anomalies, brightness inconsistencies, or system errors.
▶ Recommendation: Always consult the manufacturer or a qualified technical supplier before changing scan modes. Forced replacement without validation may result in costly rework.
Practical Purchasing Advice
At the project planning stage, confirm the scan mode and drive architecture of LED modules with your supplier to ensure compatibility with the control system and avoid late-stage risks.
For custom installations or rental displays, scan mode affects the IC count, power configuration, PCB design, and total cost structure—and should be included in your budget evaluation.
Clearly specify scan mode as a technical parameter in RFQs, BOMs, and bid documents to avoid mismatches or integration issues caused by incompatible module models.
Prefer vendors or engineering teams who offer end-to-end system integration and pre-sale technical evaluation, ensuring smooth execution from selection to deployment and maintenance.
Conclusion
While scan mode may not be as visually apparent as pixel pitch, it plays a crucial behind-the-scenes role in determining overall LED display performance, system stability, and project cost-efficiency. From brightness and refresh rate to driver structure and wiring complexity, the scan mode you choose has a lasting impact on how your display performs and how efficiently it operates.
By thoroughly understanding the differences between 1/4 scan and 1/8 scan, and their respective application scenarios, you’ll be equipped to make more informed, balanced, and cost-effective decisions during the planning and configuration stages—avoiding compatibility issues or unnecessary resource waste from chasing the wrong specifications.
If you’re planning a project and need expert guidance on scan mode selection or want a deeper understanding of LED control systems and driver architecture, feel free to contact the professional team at LEDScreenParts.com. We’re here to provide customized technical support and full-service implementation solutions tailored to your needs.