论文部分内容阅读
数字微镜器件(DMD)具有较高的刷新速率和衍射效率,是理想的动态计算全息图加载器件。采用发光二极管(LED)作为光源来代替激光可以有效减少由激光的时间和空间相干性带来的散斑噪声。提出了一种以LED为光源、以DMD为计算全息图承载器的全息显示系统。研究了DMD进行全息显示的调制特性,分析了LED作为再现光源导致像质变差的原因,并用数值仿真的方法验证了LED的相干性和准直度对DMD全息显示系统再现像像质的影响。根据仿真分析结果,采用滤色片和空间滤波器来提高LED的相干性,同时采用非球面准直透镜来改善光的利用效率,最终得到了较好的显示效果。
Digital micromirror device (DMD) with high refresh rate and diffraction efficiency, is the ideal dynamic computing hologram loading device. The use of light-emitting diodes (LEDs) as a light source instead of a laser can effectively reduce the speckle noise caused by the temporal and spatial coherence of the laser. A holographic display system with LED as light source and DMD as hologram carrier is proposed. The modulation characteristics of the holographic display of the DMD are studied. The reason why the quality of the LED as a reproducing light source is deteriorated is analyzed. The effect of the coherence and the collimation of the LED on the reproduced image quality of the holographic DMD display system is verified by numerical simulation. According to the simulation results, the color filter and the spatial filter are used to improve the coherence of the LED, and the aspheric collimating lens is used to improve the light utilization efficiency. Finally, a better display effect is obtained.