Ultra-fast speed, low grating lobe optical beam steering using unequally spaced phased array technique

In this paper, we present a low grating lobe optical beam steering technique using an unequally spaced phased array, in which the required spacings among the phase elements are quantitatively analyzed so that the grating lobe can be minimized by destructive interference. A large grating lobe is one of the major drawbacks of optical phased array technology because it limits the light efficiency and the quality of the light beam. Thus, the low grating lobe technique presented in this paper could substantially improve the light efficiency and the quality of light beam, and could potentially be used in a variety of applications such as fast speed ladar beam steering, large size high resolution displays, and wide bandwidth free space optics communications.