Optical phased array for depolarized optical beam control

A method for steering an optical beam having a polarization state with a first polarized component and a second polarized component, said method comprising the steps of:

• directing the optical beam into a first layer of transparent electro-optically active material sandwiched between two electrode layers, the layer of electro-optically active material oriented so as to phase shift only one polarized component;
• applying drive voltages to the electrode layers;
• rotating the polarization state of the optical beam to produce a rotated optical beam;
• and
• directing the rotated optical beam into a second layer of transparent electro-optically active material sandwiched between two electrode layers, the layer of electro-optically active material oriented so as to phase shift only one polarized component.

An optical phased array comprising:

• an optical window oriented to receive an incident optical beam having a polarization state with a first polarized component and a second polarized component, the second polarized component orthogonal to the first polarized component;
• a first upper transparent electrode layer positioned beneath said optical window;
• a first transparent electro-optic layer positioned beneath said first upper transparent electrode layer, said first transparent electro-optic layer receiving said incident optical beam and aligned so as to phase shift a first polarized component;
• a first lower transparent electrode layer positioned beneath the first transparent electro-optic layer such that the first transparent electro-optic layer is sandwiched between the first upper transparent electrode layer and the first lower transparent electrode layer;
• a polarization rotator positioned beneath the first lower transparent electrode layer, the polarization rotator receiving the incident optical beam from the first transparent electro-optic layer and rotating its polarization state;
• a second upper transparent electrode layer positioned beneath the polarization rotator;
• a second transparent electro-optic layer positioned beneath the second upper transparent electrode layer, the second transparent electro-optic layer receiving the optical beam from the polarization rotator and aligned so as to phase shift a polarized component parallel to the first polarized component;
• a second lower transparent electrode layer positioned beneath the second electro-optic layer such that the second transparent electro-optic layer is sandwiched between the second upper transparent electrode layer and the second lower transparent electrode layer;
• a first voltage controller connected to the first upper transparent electrode layer and to the first lower transparent electrode layer to control a first set of voltages between the first upper transparent electrode layer and the first lower transparent electrode layer, the first set of voltages creating local variations of refractive index in the first transparent electro-optic layer;
• and
• a second voltage controller connected to the second upper transparent electrode layer and to the second lower transparent electrode layer to control a second set of voltages between the second upper transparent electrode layer and the second lower transparent electrode layer, the second set of voltages creating local variations of refractive index in the second transparent electro-optic layer.