Electrostatic actuation for diffractive optical devices

A method for controlling a beam of optical radiation, the method comprising:

• directing the beam of optical radiation toward a device comprising:
• a first planar substrate having a first face and comprising a first diffractive structure disposed on the first face;
• a second planar substrate having a second face and comprising a second diffractive structure disposed on the second face;
• a first planar electrode disposed on the first face;
• a second planar electrode disposed on the second face;
• and
• a mount holding the second planar substrate parallel to the first planar substrate, with the second face adjacent to the first face and with the first and second planar electrodes in mutual proximity, while permitting the second planar substrate to move transversely relative to the first planar substrate;
• and
• applying an electrical potential between the first and second planar electrodes with a voltage sufficient to shift the second diffractive structure transversely relative to the first diffractive structure, thereby modifying an optical property of the beam.

A method for fabricating an optical device, comprising:

• forming a first diffractive structure on a first face of a first planar substrate;
• forming a second diffractive structure on a second face of a second planar substrate;
• depositing a first planar electrode on the first face;
• depositing a second planar electrode on the second face;
• mounting the second planar substrate parallel to the first planar substrate, with the second face adjacent to the first face and with the first and second planar electrodes in mutual proximity, while permitting the second planar substrate to move transversely relative to the first planar substrate;
• and
• coupling a control circuit to apply an electrical potential so as to shift the second diffractive structure transversely relative to the first diffractive structure.