Field-sequential color (FSC) technology is a display method that eliminates the need for traditional color filters by rapidly cycling through red, green, and blue (RGB) illumination in sequence. Unlike conventional displays that rely on spatial color patterning—where subpixels of different colors are arranged side by side—FSC displays present each primary color in full-screen succession at a speed fast enough for the human visual system to blend them into a full-color image. This approach offers several advantages, including higher optical efficiency, reduced power consumption, and the potential for higher resolution since it avoids the subpixel arrangement required in spatial color methods.

The core principle of FSC relies on the persistence of vision, a phenomenon where the human eye retains an image for a brief moment after the light source has disappeared. By cycling through RGB colors at a high enough frequency, the brain perceives a continuous full-color image rather than individual color flashes. The critical factor is the refresh rate, which must exceed the flicker fusion threshold—the frequency at which intermittent light appears continuous to an observer. For most people, this threshold lies between 60 Hz and 90 Hz under typical viewing conditions. To ensure smooth color blending without flicker, FSC systems typically operate at refresh rates of 180 Hz or higher, with each RGB frame displayed for an equal duration within a single cycle.

Microelectromechanical systems (MEMS) modulators play a crucial role in enabling FSC technology, particularly in microdisplay applications such as augmented reality (AR) and virtual reality (VR) headsets. MEMS-based displays, such as those using digital light processing (DLP) or laser beam scanning (LBS), can switch between colors extremely quickly. For example, DLP chips employ arrays of microscopic mirrors that tilt to reflect light either toward or away from the screen, modulating brightness at microsecond speeds. When combined with a rapidly cycling RGB light source, these modulators can produce high-quality FSC images without motion artifacts or color breakup.

One of the primary advantages of FSC over spatial color-patterning methods is improved light efficiency. In traditional LCDs, color filters absorb roughly two-thirds of the backlight’s white light, allowing only a narrow band of red, green, or blue to pass through each subpixel. In contrast, FSC displays use the full spectrum of the backlight during each color phase, significantly reducing wasted light. This efficiency gain translates to brighter images for the same power input or lower power consumption for equivalent brightness. Additionally, since FSC does not require subpixels, the effective resolution can be higher for a given pixel density, as each pixel contributes fully to all three primary colors rather than being divided into smaller subpixel elements.

However, FSC technology faces challenges related to human perception and display performance. One issue is color breakup, also known as the rainbow effect, where rapid eye movements or high-contrast scenes cause viewers to perceive fleeting flashes of individual colors. This artifact is more noticeable in peripheral vision and can be mitigated by increasing the refresh rate or employing advanced driving algorithms that adjust color sequencing dynamically. Another limitation is the requirement for high-speed display components, including fast-response light sources and modulators, which can increase system complexity and cost.

Compared to spatial color-patterning methods like RGB stripe, PenTile, or quantum dot color conversion, FSC offers distinct trade-offs. Spatial methods provide static color presentation, eliminating motion artifacts but sacrificing light efficiency and resolution density. For instance, an RGB stripe display with a 1920x1080 resolution actually consists of 5760x1080 subpixels, as each pixel is divided into three colored elements. In an FSC display, the same resolution would require only 1920x1080 pixels, with each pixel sequentially displaying red, green, and blue. This difference becomes particularly relevant in microdisplays, where pixel pitch is constrained by physical limits.

In applications such as VR headsets, FSC’s advantages are especially pronounced. The high refresh rates needed to avoid flicker align well with the demands of low-latency head-mounted displays, where frame rates of 90 Hz or higher are already standard. Furthermore, the elimination of color filters reduces the display’s thickness and weight, critical factors in wearable devices. MEMS-based LBS systems, which use lasers and scanning mirrors to project FSC images directly onto the retina, exemplify this approach, offering compact form factors and high brightness with minimal power consumption.

Future developments in FSC technology may focus on improving color accuracy and reducing artifacts through advanced modulation techniques. For example, combining FSC with adaptive frame-rate control could minimize color breakup during saccadic eye movements. Additionally, the integration of high-efficiency light sources such as micro-LEDs or laser diodes could further enhance brightness and power efficiency. Research into human visual perception may also refine the optimal sequencing patterns and refresh rates for specific use cases, balancing performance with viewer comfort.

In summary, field-sequential color technology represents a compelling alternative to spatial color-patterning methods, leveraging rapid RGB cycling and MEMS modulation to achieve high efficiency and resolution. While challenges such as color breakup and high-speed hardware requirements persist, ongoing advancements in display technology and human factors research continue to expand its viability for applications ranging from consumer electronics to specialized AR/VR systems. As display demands evolve toward higher performance and energy efficiency, FSC stands as a promising pathway for next-generation visual solutions.