摘要 |
A new method for phase locking the color wheel in a color field-sequential projection display. At periodic interrupts, the method determines which color wheel index mark should be driven into coincidence with the Vsync signal. It does this by measuring the delay between Vsync and any index mark and then based on the current state of the spoke-sync counter and this delay value, a new next state is determined to drive the nearest index mark to Vsync to the Vsync position. At worst case this technique requires only one-half a color wheel revolution of phase correction to re-lock the system when the TV channel is changed and for the 5/2 and 7/2 spoke-sync modes, popular 50 Hz and 60 Hz modes, only one-quarter revolution of phase correction of the color wheel is required for re-lock.
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