a method for developing a map of objects in a region surrounding a location is disclosed . the method includes interrogating the region along a detection axis with a series of optical pulses and detecting reflections of the optical pulses that originate at objects located along the detection axis . a multi - dimensional map of the region is developed by scanning the detection axis about the location in at least one dimension . the reflections are detected via a single - photon detector that is armed using a sub - gating scheme such that the single - photon detector selectively detects photons of reflections that originate only within each of a plurality of zones that collectively define the detection field . in some embodiments , the optical pulses have a wavelength within the range of 1350 nm to 1390 nm , which is a spectral range having a relatively high eye - safety threshold and a relatively low solar background .