The grating substrate includes a first base substrate and a plurality of grating units on the first base substrate. The grating unit includes two control layers, a barrier structure between the two control layers, and a plurality of movable particles in a closed cavity surrounded by the barrier structure and the two control layers. The two control layers include a first control layer and a second control layer. The first control layer is located on a side of the second control layer distal from the first base substrate, and the two control layers are configured to control movement of the plurality of particles. The particles satisfy at least one of the following conditions: the particles have a refractive index smaller than a refractive index of the first control layer, or the particles are non-transparent particles.