In demos, I found the display looked impressive; my eye perceived that the still images scrolling across the 47-inch demo display stayed steady.
According to LG, the company can achieve 480Hz by using a "scanning backlight" technology that turns the Cold Cathode Fluorescent Lamp (CCFL) backlight on and off in sequence, one rectangle at a time, to reduce motion blur. When this scanning backlight technology is implemented together with LG's 240Hz technology, the display can effectively refresh the image at 480Hz — and the result should lead to improved image quality during scenes that have linear motion.
The prototype display panel also has a 4ms motion picture response time, down from the typical 6ms in a 240Hz display, and 8ms in 120Hz displays; this spec should also boost quality of fast moving images, says the company. LG also credits the scanning backlight technology with enabling the display to how better brightness and contrast than current LCD TV panels can provide; this display comes closer to approaching the ideal of plasma technology, which traditionally offers the best blacks in the HDTV game.
The benefit here is that LG is doing this with CCFL backlight technology, currently the most cost-effective LCD backlight technology available. LED backlights can also do selective switching to improve brightness and contrast, but LED backlit TVs carry a premium cost in electronics. "It's all a question of design trade-offs and economics," says Bruce Berkhoff, board director of LG Display.
Increasingly, energy consumption is of concern to LCD panel manufacturers — given the ongoing push for environmentally friendly products. There's even pending legislation in California that could make it a requirement that HDTV manufacturers only sell their most ecologically sound models in that state. LG addresses power concerns by allowing you to reduce the backlight's brightness — a move that can reduce energy.
LG expects the first TV panels with TruMotion 480Hz to become available in the second half of 2009. While it is possible that we'll see an actual HDTV using the panel this year, it's a better bet that we'll see the first actual TV to use the display at CES 2010.