1. A method for assessing a function of a visual sensory field of a subject, the method comprising: obtaining a system comprising a processor and a sensor for use with the processor, the processor configured to present on a display or optical system visual stimuli over selected areas of the visual sensory field defined by sensory spatial dimensions defined in units of angle or length of the visual sensory field, the selected areas being centered at points on a sampling grid of the display or optical system wherein individual visual stimuli each spans a portion of the visual sensory field, and each is selectively presented in a distinct associated area, wherein the distinct associated area of at least one of said individual visual stimuli overlaps a portion less than all the distinct associated area of at least one other of said visual stimuli such that spatial aliasing of the visual stimuli of the sampling grid is minimized, and profiles of the visual stimuli are smoothly varying such that the individual visual stimuli comprise mainly spatial frequencies that are less than or equal to a highest spatial frequency that can be represented by the sampling grid, wherein the highest spatial frequency is a Nyquist sampling frequency defined by a density of the visual stimuli in the sampling grid, the sensor configured to detect responses in the subject's visual sensory field evoked by the stimuli and generate inputs representative of the responses; using the processor to present visual stimuli including the one and one other visual stimuli; using the sensor to detect responses in the subject's visual sensory field evoked by the visual stimuli including responses evoked by the one and the one other visual stimuli and generate the inputs representative of the responses evoked by at least the one and the one other visual stimuli, the processor configured so that the overlap of the distinct associated areas of the at least one and at least one other visual stimuli presented by the processor and smooth varying of the profiles of the visual stimuli presented by the processor avoid undersampling and reduce distorting effects of aliasing of high spatial frequency variations in visual function of the subject; and through the processor, processing the inputs to thereby estimate a functional response of the subject's visual sensory field at the selected areas using the detected responses.