摘要
自行研制的外部导入宽可调谐激光的积分球光源中为了提高光辐射场的均匀性和稳定性,采用球内旋转漫射板方法去除激光相干性产生的散斑。为了定量评价退相干效果和漫射板旋转速率之间的关系,使用响应度均匀性经过校正的CCD对积分球出口成像,计算不同积分时间、不同转速条件下的散斑对比度。实验结果表明,漫射板只需在很低的速率下旋转就能完全去除散斑噪声。漫射板不旋转时,散斑对比度约为30%;散斑完全去除时,对比度降为5%。
In the newly developed laser-illuminated integrating sphere source, speckle in the image from the source is effectively removed by rotating diffusers in the sphere to improve the uniformity and stability of the radiation field. The specific relationship between the speckle removal effect and the rotation frequency of the diffusers is evaluated. Speckle contrast of the exit port image is calculated under different rotating speed and different CCD integrating time. We have checked that the speckle noise is reduced to a negligible level by rotating the diffuser at very low frequencies. The speckle contrast is approximately 30% when the diffusers are motionless, and it is reduced to 5% when the speckle is removed.
出处
《光电工程》
CAS
CSCD
北大核心
2010年第5期32-36,共5页
Opto-Electronic Engineering
基金
863项目(2007AA12Z106)
关键词
激光散斑
积分球
漫射板
散斑对比度
laser speckle
integrating sphere
diffusers
speckle contrast
