An imaging device including at least one imaging array and image formation optics that provide a field of view corresponding to the imaging array. At least one illumination module (which includes at least one source of coherent illumination) produces planar light illumination that substantially overlaps the field of view corresponding to the imaging array. Illumination control circuitry modulates the power level of illumination produced by the source of coherent illumination during each photo-integration time period of the imaging array to thereby reduce speckle noise in images captured by the imaging array. The illumination control circuitry preferably modulates the power level of illumination by controlling the number and/or duration of time periods corresponding to different power levels of illumination produced by the source of coherent illumination during each photo-integration time period of the imaging array. Moreover, the illumination control circuitry preferably controls number and/or duration of the time periods such that substantially constant energy is produced by the source of coherent illumination over the time periods (thereby enabling the different speckle patterns produced over the timer periods to optimally cancel each other out).