Abstract: An alternate eye 3-d projection system has a projector projecting alternate eye left and right images, has alternating eye 3-d glasses alternating between left and right lens transmissiveness, and has a phase delay unit synchronizing the left lens transmissiveness to left images and right lens transmissiveness to right images. A timing shutter is driven through a mechanical link to the projector primary mechanism at a frequency proportional to the frequency of the transition between images. A sensor outputs pulses according to the rotationally frequency of the timing shutter. The phase delay unit receives the pulses, a multiplier multiplies the frequency of the pulses, a phase lock loop locks on to the frequency and a counter counts the pulses. After a preset delay the counter outputs a pulse. The delay is adjustable. The counter pulse enables a 60 KHz oscillator. The oscillations are counted by another counter and passed to a transmitter.