What Scan Modes Are Used in LED Displays?

As LED display technology continues to advance, people expect higher brightness, smoother refresh rates, and better overall stability. One of the key factors that determines these performance levels is the scan mode used in an LED screen. Understanding LED display scanning methods helps buyers choose the right product, especially when brightness, cost, and image quality matter.

An LED display contains thousands—or even millions—of LED lamps. If all LED pixels were lit simultaneously, the LED driver IC would require an extremely large number of pins, making the circuit complicated and very expensive. Therefore, LED displays use time-division lighting, where rows or columns of LEDs light up sequentially rather than all at once. This time-division method is what we call the LED display scan mode.

Types of LED Display Scan Modes

LED display scan modes fall into two main categories:

• Static Drive
• Dynamic Drive (Scan Drive)

Among the two, dynamic scan LED displays are far more common because they reduce hardware cost while ensuring stable performance.

1. Static Drive LED Display

A static drive LED display assigns one dedicated driver channel to each LED lamp. Because every pixel stays continuously illuminated, static scan screens achieve extremely high brightness and outstanding image stability. They do not flicker, and cameras can capture them without scan lines or distortion.

However, static LED displays require far more driver IC pins, making them significantly more expensive. As a result, they are usually reserved for high-end or professional LED applications, such as broadcast studios and premium indoor displays.

Key features of static drive LED displays:

• Very high brightness
• Extremely stable image with no flicker
• Highest level of camera compatibility
• High cost due to more driver ICs

2. Dynamic Drive LED Display (Scanning Mode)

A dynamic scan LED display uses time-division multiplexing. In this structure, LED lamps are arranged in a matrix of rows and columns. The LED driver IC divides its pins into row-selection terminals and column-data terminals. By quickly switching which row is active at any given moment, the system makes every row light up sequentially in rapid cycles.

Because of the persistence of vision effect (about 1/24 second), the human eye perceives the LEDs as continuously bright, even though only part of the screen is lit at any instant.

Dynamic LED scanning reduces driver IC usage dramatically and lowers hardware cost.

Common dynamic scan ratios include:

• 1/4 scan
• 1/8 scan
• 1/16 scan
• 1/32 scan

The number in the denominator indicates how many groups the rows are divided into. For example, a 1/16 scan LED module lights only 1 out of 16 row groups at any given moment.

Rule of thumb:
The higher the scan ratio (the larger the denominator), the lower the average brightness.

Static vs. Dynamic Scan LED Displays: A Comparison

How to Choose the Right Scan Mode

Choosing an LED display scan mode involves balancing brightness, cost, refresh rate, and power consumption. Here are several practical rules:

1. Scan Mode vs. Brightness

Higher scan ratios (such as 1/16 scan) reduce the number of lit rows at any instant, lowering average brightness. To compensate, LED driver ICs use higher pulse currents during illumination, helping the screen maintain adequate brightness.

Therefore, a 1/16 scan LED display may produce a high peak current but still maintain reasonable average power consumption.

2. Scan Mode vs. Pixel Density

• Outdoor LED displays:
  With larger LED lamps and higher brightness requirements, they usually adopt lower scan ratios such as 1/2 scan or 1/4 scan, ensuring better brightness.
• Indoor LED displays:
  Because they have high pixel density and require less brightness, they typically use 1/8 scan or 1/16 scan, reducing cost and heat output.

3. Impact on Visual Performance

Scan mode affects viewing experience in several ways:

• Refresh Rate:
  Low refresh rates can cause flicker when the viewer moves their eyes quickly. Cameras may capture scan lines, which is noticeable in poorly designed dynamic-scan screens.
• Ghosting:
  If the driver IC does not handle blanking properly, some LEDs may show faint unwanted light.

This is why a well-designed 1/16 scan LED screen can outperform a poorly designed 1/4 scan LED screen, even though the latter technically has lower scanning.

Final Thoughts

You don’t need to obsess over scan ratio numbers when buying an LED display. Instead, look at the real-world performance indicators—brightness, refresh rate, stability, and visual quality. Static drive LED displays offer the best performance but come at a premium. Dynamic scan LED displays remain the mainstream choice because they balance cost and functionality effectively.

A properly engineered LED display, regardless of whether it’s 1/8 scan or 1/16 scan, can still deliver excellent visual quality for most indoor and outdoor applications.

1. Does a higher scan ratio reduce brightness?

Yes. A higher scan ratio—such as 1/16 scan—means fewer rows are lit at once, which lowers average brightness. However, LED driver ICs use pulse-current compensation to maintain acceptable brightness levels.

2. Which scan mode is better for indoor LED screens?

Indoor LED displays typically use 1/8 or 1/16 scan because they have higher pixel density and do not require extreme brightness, making dynamic scan a cost-effective choice.

3. Will scan mode affect camera performance and visual stability?

Yes. Poorly designed scan circuits may cause flicker, scan lines, or ghosting. A well-designed 1/16 scan LED display can still deliver excellent visual stability and high refresh rates suitable for filming.