Mitchell Kevin J, Turtaev Sergey, Padgett Miles J, Čižmár Tomáš, Phillips David B
Opt Express. 2016 Dec 12;24(25):29269-29282. doi: 10.1364/OE.24.029269.
The dynamic spatial control of light fields is essential to a range of applications, from microscopy to optical micro-manipulation and communications. Here we describe the use of a single digital micro-mirror device (DMD) to generate and rapidly switch vector beams with spatially controllable intensity, phase and polarisation. We demonstrate local spatial control over linear, elliptical and circular polarisation, allowing the generation of radially and azimuthally polarised beams and Poincaré beams. All of these can be switched at rates of up to 4kHz (limited only by our DMD model), a rate ∼2 orders of magnitude faster than the switching speeds of typical phase-only spatial light modulators. The polarisation state of the generated beams is characterised with spatially resolved Stokes measurements. We also describe detail of technical considerations when using a DMD, and quantify the mode capacity and efficiency of the beam generation. The high-speed switching capabilities of this method will be particularly useful for the control of light propagation through complex media such as multimode fibers, where rapid spatial modulation of intensity, phase and polarisation is required.
光场的动态空间控制对于从显微镜到光学微操纵及通信等一系列应用至关重要。在此，我们描述了使用单个数字微镜器件（DMD）来生成并快速切换具有空间可控强度、相位和偏振的矢量光束。我们展示了对线性、椭圆和圆偏振的局部空间控制，能够生成径向和方位角偏振光束以及庞加莱光束。所有这些光束都可以以高达4kHz的速率进行切换（仅受我们的DMD型号限制），该速率比典型的仅相位空间光调制器的切换速度快约2个数量级。通过空间分辨斯托克斯测量对所生成光束的偏振态进行了表征。我们还描述了使用DMD时的技术考量细节，并对光束生成的模式容量和效率进行了量化。这种方法的高速切换能力对于控制光通过诸如多模光纤等复杂介质的传播将特别有用，在这种情况下需要对强度、相位和偏振进行快速空间调制。
