Photoaddressed spatial light modulators (PSLM) based on nematic liquid crystals using hydrogenated amorphous silicon-carbon films (a-Si1-xCx,:H) and p-i-n structures as photosensitive layers are designed and studied. It is shown that an application of a-Si1-xCx:H p-i-n diodes greatly improved the operation speed of a PSLM, increased the film transparency and decreased the absorption of the red readout light. As a result, the readout light intensity could become ≈ 20 times larger. The maximum diffraction efficiency of the PSLM was achieved for a write-in light intensity of 40μLW/cm2, with a resolution (FWHM) of the diffraction efficiency of 54 mm-1. The optical response of the PSLM was observed in the frequency range from 1 Hz to 100 Hz.