基于光纤振动的激光散斑抑制方法的研究

Research of laser speckle suppression method based on fiber vibration

为了解决激光显微成像系统中散斑的抑制问题,采用散斑暗区比方法研究了光纤振动对显微散斑图像的影响。实验中采用波长为532nm的激光作为显微系统光源,利用光纤振动对激光显微图像散斑进行抑制;同时采用CCD图像传感采集系统对样品表面进行的显微成像,并对光纤在不同振动电压下的显微图像暗区比进行了分析。结果表明,随着振动电压的增大,图像的散斑暗区比会逐渐减小,当电压为2.6V时,图像散斑暗区比达到5.64%,散斑对比度为4.17%,接近人眼分辨率4%,可达到良好的散斑抑制效果。

In order to eliminate the speckle in laser microscopic imaging system,effect of optical fiber vibration on microscopic speckle images was studied by comparing the speckle dark ratio. In this experiment,with laser at 532 nm wavelength as light source of the microscopic system,with the optical fiber vibration to eliminate the image speckle and a CCD image sensor acquisition system to collect the microscopic images of the sample surface,images dark ratios were analyzed at different vibration voltages. The results show that with the increase of the vibration voltage,the speckle dark ratio of the images will reduce gradually. When the voltage is 2. 6V,the image speckle dark ratio can reach 5. 64%,speckle contrast is 4. 17% close to human eye resolution of 4%. This method can achieve good speckle elimination effect.