Dispersion of speckle suppression efficiency for binary DOE structures: spectral domain and coherent matrix approaches

作者：Lapchuk, Anatoliy; Prygun, Olexandr; Fu, Minglei; Le, Zichun^*; Xiong, Qiyuan; Kryuchyn, Andriy

来源：Optics Express, 2017, 25(13): 14575-14597.

DOI：10.1364/OE.25.014575

• DIFFRACTIVE OPTICAL-ELEMENTS
• LASER PROJECTION DISPLAYS
• REDUCTION
• SPEED

We present the first general theoretical description of speckle suppression efficiency based on an active diffractive optical element ( DOE). The approach is based on spectral analysis of diffracted beams and a coherent matrix. Analytical formulae are obtained for the dispersion of speckle suppression efficiency using different DOE structures and different DOE activation methods. We show that a one-sided 2D DOE structure has smaller speckle suppression range than a two-sided 1D DOE structure. Both DOE structures have sufficient speckle suppression range to suppress low-order speckles in the entire visible range, but only the two-sided 1D DOE can suppress higher-order speckles. We also show that a linear shift 2D DOE in a laser projector with a large numerical aperture has higher effective speckle suppression efficiency than the method using switching or step-wise shift DOE structures. The generalized theoretical models elucidate the mechanism and practical realization of speckle suppression.

• 出版日期2017-6-26
• 单位浙江工业大学