Abstract: A optical system and imaging device provide simultaneous or sequential optogenetic stimulation of different locations within a biological sample and fluorescence imaging of the locations. The systems include an illumination array with multiple electrically addressable elements that select a spatial pattern of illumination, an optical fiber bundle with fibers coupled between the array element and target locations at the sample, a fluorescence illumination source, and an imaging system for measuring fluorescence returning from the target locations. The optical imaging devices include a housing and a sample connector configured for receiving a first optical fiber bundle connection including multiple optical fibers. The sample connector has an indexing feature to maintain a fixed relationship between the fibers and internal optical paths of the device.