Prototypes of matrix multichannel spatial-temporal light modulators (STLM) based on liquid crystals (LC) developed so far do not match the operating capacity of optical computing systems by their characteristics (response speed, capacity), One of the ways to increase the speed of response of STLM is to realise the modulation mode that arises under deformation of near-electrode LC layers. This paper presents the results of investigation of the modulation characteristics of the STLM light valves based on twist-effect under conditions of initial distortion of LC-layer director that is caused by contact of the liquid crystal with the periodic structure of the modulator electrodes.