this invention describes a device for optical stimulation of cells and other biological structures . it has an ability to target multiple cells and / or multiple sub - cellular targets . the stimulation optical pattern on each cell can be independently controlled with individual frequencies . the light sensitivity of the cells can be imparted as a result of genetic expression of surface and / or subsurface proteins , chemical modification of existing proteins , or via the release of caged entities which in turn act to stimulate the cell through chemical means . the embodiment is capable of functioning on neurons but can also be used for other cells . it can perform optimal stimulation with sub - cellular resolutions , record the activity of the targeted cells and perform processing to ensure calibration .