Motion Resolution / MPRT

MPRT vs. Pixel Response Time (GtG)

MPRT (Moving Picture Response Time) is often confused with GtG (Gray-to-Gray) response time, but they measure fundamentally different phenomena. GtG measures how quickly a pixel transitions between two colors, a property of the pixel itself. MPRT measures display persistence: how long a pixel remains continuously visible on screen. A display can have fast GtG (pixel colors change rapidly) but high MPRT (each frame stays bright for a long duration), or conversely, slow GtG with improved MPRT through strobing technology.

The Sample-and-Hold Mechanism

Most modern LCD and OLED displays operate in sample-and-hold mode: they display a complete frame and hold it lit until the next refresh cycle replaces it. When a viewer's eyes track a moving object on screen, the object's image remains stationary on the viewer's retina while the eye moves to follow it. This creates a smear or blur effect across the retina, independent of how fast individual pixels change color. This persistence blur occurs in both LCD and OLED displays during normal sample-and-hold operation, despite OLEDs having pixel response times below 0.1 milliseconds.

MPRT and Refresh Rate Relationship

For non-strobed sample-and-hold displays, MPRT is approximately 1000 milliseconds divided by the refresh rate in Hertz. A 60Hz display has roughly 16.67ms of MPRT; a 120Hz display approximately 8.33ms; a 240Hz display roughly 4.17ms; and a 144Hz display approximately 6.9ms. Higher refresh rates proportionally reduce persistence blur, but do not eliminate the sample-and-hold effect itself. Even at 360Hz (2.8ms per frame), persistence remains inherent to standard LCD and OLED operation.

Reducing Motion Blur Without Higher Refresh Rates

Motion blur reduction can be achieved independent of refresh rate through strobing technology. On LCDs, this involves flashing the backlight on and off between frames, reducing how long each image persists on the retina. On OLEDs, the equivalent is accomplished by rapidly turning pixels on and off. These strobing techniques can achieve significant blur reduction even at lower refresh rates, though specific magnitude figures vary by implementation and require direct measurement.

Measurement Methods

The UFO MPRT test, developed by Blur Busters, displays vertical bars scrolling horizontally across the screen. Display persistence causes the bars to thicken and overlap; MPRT is measured by identifying the pair of bars that touch edge-to-edge without overlapping or leaving a gap. Third-party measurement labs like RTINGS use pursuit/panning cameras to approximate eye-tracking of moving graphics, typically scrolling at 960 pixels per second, to quantify motion blur independently.

The "1ms MPRT" Myth

Marketing claims of "1ms MPRT" on non-strobing displays are misleading. Achieving true 1ms MPRT without strobing would theoretically require 1000Hz refresh rate, 1000fps source content, and reliable 1ms pixel response times across the display, none of which are currently standard. When a manufacturer claims 1ms MPRT without specifying strobing technology, the claim should be treated as a marketing exaggeration rather than a measured specification.

VESA ClearMR Standard

In August 2022, VESA introduced ClearMR (Clear Motion Ratio) as an alternative motion-blur measurement standard. ClearMR tiers range from ClearMR 3000 to ClearMR 9000, with higher numbers indicating less blur. For example, ClearMR 7000 indicates a ratio of 6500 to 7500 percent more clear pixels than blurry pixels. VESA developed ClearMR because MPRT alone does not capture blur quality when displays use image enhancement techniques, such as overshoot and undershoot, that can introduce visual artifacts despite low measured MPRT. The VESA ClearMR certification program limits these enhancement techniques during testing, allowing consumers to compare motion blur quality fairly across certified displays.

Community Heuristics

Display-enthusiast communities (such as Blur Busters forums) have circulated an informal rule: roughly one pixel of blur is added per millisecond of display persistence per 1000 pixels per second of on-screen motion. This heuristic is widely referenced but has not been independently validated or peer-reviewed, and should be understood as a community rule-of-thumb rather than an established measurement standard.