Variable duty cycle optical pulses

An apparatus for impressing an optical beam, the apparatus comprising:

• a DC power supply generating a DC voltage;
• a voltage control unit (VCU) generating an AC voltage;
• an electro-optic field modulator configuration coupled to receive the optical beam and the DC and AC voltages from the DC power supply and the VCU, the electro-optic field modulator configuration modulating the received optical beam based on the DC and AC voltages applied to the electro-optic field modulator configuration to produce an optical signal of tuned duty cycle pulses having an output power corresponding to an output power versus drive voltage curve with a characteristic half-wave voltage, Vpi, situated midway between a pair of zero power transmittance derivative power points on the curve, wherein the output power satisfies the criteria of having a single maximum value within the bit slot, minimum values at the bit boundaries, and zero derivatives of the output power with respect to time only at the maximum value within the bit slot and the minimum values at the bit boundaries,
• the tuned duty cycle pulses
• having a duty cycle defined by the magnitudes of the DC and AC voltages and a frequency defined by the frequency of the AC voltage for providing a predetermined amount of destructive optical interference for tuning the duty cycle and the duty cycle is inversely related to the bit period;
• and
• a controller coupled to the DC power supply and the VCU, the controller generating at least one control signal to control respective magnitudes of the DC and AC voltages for setting the AC voltage and setting the DC voltage such that the maximum power transmittance point on the curve is less than 100% for tuning the duty cycle.