A method includes capturing measurements of optical signals transmitted from an optical phased array that includes (i) multiple array elements each having an antenna element and a phase modulator and (ii) an additional antenna element spaced apart from the array elements. The method also includes performing digital holography using the measurements to identify relative phases of the array elements with respect to a phase of the additional antenna element. In addition, the method includes modifying phases provided by at least some of the phase modulators of at least some of the array elements to bring the array elements more closely into phase with one another.