Existing HDTV Scanning Backlights


Some manufacturers have added scanning backlights to their high-end HDTV’s to reduce perceived motion blur.

From Sony website (sony.com):

“The model also features Sony’s MotionFlow XR 960 featuring a precise backlight control that is synchronized with the liquid crystal movement from frame to frame creating clearer, sharper moving images.”
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From Samsung website (samsung.com):

“Backlight technology: Samsung’s backlight regulates output precisely in synchronization with the screen refresh to lessen the time it is lit, reducing ghosting and motion blur.”
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From Elite(tm) HDTV website (elitelcdtv.com):

“FluidMotion, which combines an advanced frame creation system with unique scanning backlight technology, to create a greater than 240Hz effect – improving picture clarity and smoothness in movies and sports content.”
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From Panasonic website (panasonic.com):

“a super high speed 1920 Backlight Scanning for higher moving picture resolution during fast action scenes”
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Several manufacturers have come up with different terminologies to describe the motion blur reduction benefits on LCD, including Sony’s “XR 960” and Samsung’s “CMR 960”. Samsung’s Clear Motion Rate (CMR) utilizes combination of motion interpolation (i.e. converting 60fps into 120fps or 240fps) and a scanning backlight. This combination works together to greatly reduce motion blur on LCD displays.

However, motion interpolation have disadvantages that interfere with computer use and video gaming including input lag and motion interpolation artifacts. Input lag manifests itself as lag in mouse/keyboard response during computer use, and as lag in controls during video games. Thus, motion interpolation is generally not suitable for computer monitors, due to low latencies required.

A major notable exception: Certain newer Sony HDTV’s in the HX950 series and KDL-55W905A., have a new special “Motionflow Impulse” setting (similiar to LightBoost) that works better for computers and video games, without using motion interpolation. It works very well in eliminating most motion blur on these Sony HDTV’s, and works in Game Mode.

Newer strobe backlight technologies are getting better. Older scanning backlights from 2010 and prior did not work very well, had terrible performance. Also, BENQ did an early strobe backlight with AMA-Z in 2006 that did not work very well compared to today. Newer scanning backlights or strobe backlights (2012 and newer) are significantly superior. Some strobe backlight technologies (e.g. LightBoost) permit an order-of-magnitude reduction in motion blur.  PixPerAn motion tests have shown that recent LightBoost LCD displays have 92% less motion blur than a standard 60 Hz LCD display!  In comparison, regular 120 Hz LCD’s only have 50% less motion blur than 60 Hz LCD’s.

It is now possible to design a scanning backlight or strobed backlight suitable for computer and gaming use, to completely eliminate LCD motion blur. This is currently being successfully done in some models of ASUS, BENQ and Samsung 120 Hz computer monitors. See the LightBoost HOWTO to configure your display.

In addition, it is also now possible for all manufacturers to design a scanning or strobe backlight with existing technologies, utilizing off-the-shelf components, from freely available knowledge, and without using motion interpolation. See Electronics Hacking: Creating a Strobe Backlight. Such backlights can be engineered to have nearly no input lag. This makes them computer and video-game friendly. For more information about scanning/strobed/flashing backlight design, see the Scanning Backlight FAQ.