Dynamic coherence control of random lasers and its effect on speckle and edge sharpness of images

In this Letter, we designed a random laser based on a nematic liquid crystal with titanium nitride nanoparticles, which has low spatial coherence, and its spatial coherence can be dynamically manipulated by the applied voltage.In a scattering environment, the speckle effect can be effectively suppressed using the random laser as the light source, and the speckle degree is controlled by the applied voltage.Moreover, with the decrease of the spatial coherence of the random laser, the imaging edges become blurred.We provided a quantitative way to optimize the image quality between uniformity and edge sharpness while improving the signal-to-noise ratio.