The present invention relates to a device which can steer at the same time RF waves and optical beams with different amounts of steerage being applied to the RF waves verses the optical beams.
This invention combines two technological thrusts, namely, optical beam steering and RF wave beam steering using a common reflective surface. The combination provides a single aperture that steers both types of beams simultaneously, yet differently.
In the prior art, both RF beam steerers and optical beam steerers are known. In terms of optical beams steerers, exemplary prior art designs include those disclosed by U.S. Pat. Nos. 5,093,740; 5,943,159 and 5,963,682.
A combination RF and optical beam steerer include an optically transparent substrate having first and second major surfaces, the first surface having disposed thereon an array of conductive elements associated with a radio frequency beam steerer and the second surface thereof having an array of elements disposed thereon associated with an optical beam steerer. The spacing of the elements in the RF beam steerer is at least 10 times the wavelength of the optical energy to be steered by the device so that the RF beam steerer appears to be essentially optically transparent to the optical energy. Further, in order for the optical beam steerer to function as a ground plane for the RF beam steerer, the array associated with the optical beam steerer preferably has a spacing 1000 times less than the wavelength of the RF energy to be steered.