Illumination Angle Three-Dimensional Model for Speckle Noise Suppression in Laser Projector

Angle diversity is widely used for speckle noise reduction in laser projector system. In this paper, the limitation of the existing model for illumination angles producing uncorrelated speckle patterns is discussed. A three-dimensional model of the variation illumination angles in spherical coordinate system is set up. A new parameter ΔΦ is brought in and the formula of the magnitude of the transverse component of the scattering vector difference is derived. Based on the new derivation, the minimal angle difference is investigated theoretically and numerical calculation in spherical coordinate system.