Generally. speckle noise is regarded as unavoidable in holographic projection. and it results from unexpected high spatial frequency components of diffracted light at the sharp edge of pixel openings in a spatial light modulator. Speckle noise typically reduces image contrast and degrades the image quality of the holographic projection. https://www.bekindtopets.com/special-pick-Grandpa-s-Best-Prairie-Hay-quick-pick/