Energy-efficient dispersion compensation for digital micromirror device

Due to the wave nature of light, the diffraction pattern generated by an optical device is sensitive to the shift of wavelength. This fact significantly compromises the digital micromirror device (DMD) in the applications, such as full-color holographic display and multi-color fluorescence microscopy. The existing dispersion compensation techniques for DMD involve adding diffractive elements, which causes a large amount of waste of optical energy. Here, we propose an energy-efficiency dispersion compensation method, based on a dispersive prism, for DMD. This method simulates the diffraction pattern of the optical fields reflected from the DMD with an angular spectrum model. According to the simulation, a prism and a set of optical components are introduced to compensate for the angular dispersion of DMD-modulated optical fields. In the experiment, our method reduced the angular dispersion, between the 532nm and 660nm light beams, by a factor of ~85. Compared to the methods based on diffractive elements, our method improved the optical energy efficiency by a factor of ~2.