FFD

10/27/2001

FFD - Fast Forward Direction: A technology developed by Mitsubishi to speed up transition of LCD cells to new gray levels. (Colors are displayed by setting gray levels for red, yellow and blue). NTSC TV requires that colors change levels in 33ms. HDTV may require colors to change in 16ms. If the change is not completed within the required time an intermediate gray level or color will appear. This is perceived as blurring.

While most modern (circa 2001) LCDs can switch to full on or full off in less than 16ms, changing to intermediate levels can take much longer. The conventional method of setting color/gray scale has been just to set the appropriate voltage and wait. FFD attempts to speed up transitions by first turning the cell on or off -- as appropriate -- then, when the gray level is approximately the desired level, switching to the holding voltage. This technique results in far faster switching of gray/color levels. Moreover, FFD does not require changes to the underlying physical screen construction. It is compatible with almost any sort of LCD.

One infers that an FFD controller calibrated for one display technology might not perform well with a display with different switching characteristics.

Mitsubishi plans to ship FFD controllers in 2002.

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