The invention concerns a liquid crystal spatial light modulator (101) comprising: a liquid crystal layer (7); and on at least one side of the liquid crystal layer (7), at least one photovoltaic cell (456), each photovoltaic cell (456) comprising a photosensitive layer (5) comprising electron-donating (D) molecules and electron accepting (A) molecules, each photovoltaic cell (456) being arranged for spontaneous photovoltage under illumination. Electron-donating molecules and electron accepting molecules are preferably blended and form preferably an organic bulk heterojunction layer. The photosensitive layer (5) of each photovoltaic cell (456) is preferably comprised between: —an electron conducting layer (4) arranged for a transfer of an electron from its contacting photosensitive layer (5) easier than a transfer of an electron hole from its contacting photosensitive layer (5), and —an electron hole conducting layer (6) arranged for a transfer of an electron hole from its contacting photosensitive layer (5) easier than a transfer of an electron from its contacting photosensitive layer (5).