A one-dimensional, ultrasmall pixel liquid-crystal (LC) device is experimentally demonstrated. The device has a one-dimensional array of ten 1 mm long, interdigitated, reflective gold electrodes on a glass substrate and a common transparent electrode on the opposite substrate. The interdigitated electrodes are 2 microm wide, separated by a 1 microm interelectrode gap. Operating as a dynamic, reflective, 3 microm pitch diffractive grating, the device simulates the performance of a reflective, ultrasmall, 3 microm pixel, spatial light modulator (SLM). It was shown that, for a proper choice of LC cell thickness (less than 2 microm), LC material (Merck's BL006 high-birefringence mixture), and driving conditions, the device can attain relatively high diffraction efficiency, thus demonstrating the practical feasibility of a 3 microm pixel, LC SLM.