A speckle reduction method based on a rotating ball lens is proposed and assessed. The fast rotation of the ball lens results in angle diversity and thus reduced speckle. Furthermore, the same experiment is performed with different motor voltages, shooting distances, and laser driving currents. Efficient speckle reduction was achieved by applying our method to a complete laser projection system, resulting in a lower speckle contrast than the human speckle perception threshold of 4%. Additionally, a novel standardised speckle measurement method based on human eye characteristics was developed to evaluate the speckle contrast. The proposed method can increase opportunities for practical speckle measurement applications.

提出并评估了一种基于旋转球镜的散斑减少方法。球形透镜的快速旋转导致角度变化，从而减少了斑点。此外，在不同的电机电压，射击距离和激光驱动电流下执行相同的实验。通过将我们的方法应用于完整的激光投影系统，可以有效减少斑点，从而使斑点对比度低于人类斑点感知阈值4％。此外，开发了一种基于人眼特征的新型标准化斑点测量方法，以评估斑点对比度。所提出的方法可以增加实际斑点测量应用的机会。