激光显示中散斑对比度的降低

Speckle Contrast Reduction in Laser Display

激光显示中,散斑的存在严重影响了画面质量,降低了图像的清晰度。文章阐述了散斑的形成机理,简要介绍了减弱散斑可采取的多种方法,详细介绍了引入旋转光纤对于减弱散斑噪声的作用,并以绿光为例用实验验证了此法的可行性。光纤的引入一方面利于激光传输,减小了能量损失,而且光纤的旋转使得散斑结构不断变化,屏幕上形成"沸腾"的散斑,散斑结构的叠加使散斑的对比度有了显著的降低。

In laser display system, speckle noise which is produced by the good coherence of laser has a serious destruction to the articulation of image. This paper, firstly, summarizes how laser speckle was formed. Then,many methods to reduce the speckle were introduced briefly. In the hard core of the paper, speckle contrast reduction using a rotating optical fiber in a laser display system was expounded in detail and confirmed through experiments by taking green beam as an example. The introduction of optical fiber was advantageous to laser transmission, reducing the energy loss, with the fiber rotating the speckle on the screen was being able to change continuously and ＂boiling＂ speckle patterns emerged on the screen,leading to the speckle contrast being reduced greatly.