Suppose we have a projector with a 1920x1080 HD display chip. Displayed normally, a portion of its projected image might look like this:
Notice that the black pixel grid between the pixels is quite pronounced. This is important, because what we are going to do is fill the black space inbetween the pixels with new pixels.
The projector has a refresh rate of 120hz. Since the highest frame rate of any source material is 60 hz progressive, this allows us to display each frame twice.
With a special, computer-controlled refractor in the lens system, we can displace one of the two 1/120-second displayings of a frame by half a pixel diagonally. If that’s all we do, then each frame will get displayed like this:
Now we have twice as many pixels (not four times as many), displayed in a checkerboard pattern. Since each pixel is refreshed only 60 times per second, not 120, the pixels are half as bright, but because there are twice as many of them, the overall brightness of the image stays the same.
Notice that the black pixel grid has become virtually invisible from what it was before. However, the quality of the image has not really improved, because all we did was to copy the same information diagonally.
But — what if instead, we had the projector treat this larger set of pixels (twice as many as 1920x1080) as a single canvas, and we gave each pixel its own color, using some very sophisticated algorithms that analyze the content of the 1920x1080 source image to find object edges and things like that? Then we could produce something like this:
A dramatic improvement. And if you see it in person, as I had the chance to do at CEDIA last week, it’s even more impressive. Now I just gotta get a home theater to put one in... :)
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