Speckle suppression in digital in-line holographic microscopy through liquid crystal dynamic scattering

We demonstrate speckle noise reduction in an in-line holographic imaging system using a zwitterion-doped liquid crystal dynamic scatterer (LCDS) cell diffuser. Integrated into a minimally modified bright-field microscope, the LCDS actively modulates the system's spatial coherence. The proposed solution suppresses coherent artifacts without introducing bulky moving parts while enhancing image resolution and preserving overall system simplicity. Quantitative performance tested on a phase and amplitude test targets, as well as a phase-amplitude biological sample, shows significant noise reduction and the method's versatility. Although validated in a holographic in-line setup, the approach is applicable to other imaging techniques requiring compact, vibration-free speckle suppression.