1. A device, comprising: a detector, configured to capture frames according to a frame acquisition time; a focusing element; and an illumination source configured, in cooperation with the focusing element and the detector, to generate at least first and second images of the illumination source on the detector within a given frame, the first image and the second images forming a spatial sequence and being spatially separated from each other on the focal plane of the detector by at least one pixel, the first and the second images being generated in a temporal sequence, the illumination source having a time delay between generating the first image and the second image, the time delay being less than or equal to the frame acquisition time of the detector.