A light detection and ranging, "LIDAR", system arranged to survey a scene , the system comprising: a light source arranged to output light having a first characteristic; a spatial light modulator, "SLM", arranged to receive the light from the light source and output spatially-modulated light in accordance with computer-generated holograms displayed on the spatial light modulator ; a holographic controller arranged to output a plurality of computer-generated holograms to the spatial light modulator , wherein each computer-generated hologram is arranged to form structured light having a corresponding pattern in a replay field within the scene , and the holographic controller is further arranged to change the pattern of the structured light formed in the replay field by at least one of the plurality of computer-generated holograms; a light detector arranged to receive light having the first characteristic from the scene and output a light response signal, wherein the light detector comprises an array of light detecting elements , and an optical system associated with the array of light detecting elements , the optical system arranged such that each light detecting element receives light having the first characteristic from a respective sub-area of the replay field within the scene , wherein at least one of the plurality of computer-generated holograms is arranged to form a pattern of structured light comprising a plurality of discrete light spots of uniform brightness having a particular shape, wherein the light spots are spatially separated from each other and each light spot is arranged to illuminate a corresponding sub-area of the replay field within the scene . a light source arranged to output light having a first characteristic; a spatial light modulator, "SLM", arranged to receive the light from the light source and output spatially-modulated light in accordance with computer-generated holograms displayed on the spatial light modulator ; a holographic controller arranged to output a plurality of computer-generated holograms to the spatial light modulator , wherein each computer-generated hologram is arranged to form structured light having a corresponding pattern in a replay field within the scene , and the holographic controller is further arranged to change the pattern of the structured light formed in the replay field by at least one of the plurality of computer-generated holograms; a light detector arranged to receive light having the first characteristic from the scene and output a light response signal, wherein the light detector comprises an array of light detecting elements , and an optical system associated with the array of light detecting elements , the optical system arranged such that each light detecting element receives light having the first characteristic from a respective sub-area of the replay field within the scene , wherein at least one of the plurality of computer-generated holograms is arranged to form a pattern of structured light comprising a plurality of discrete light spots of uniform brightness having a particular shape, wherein the light spots are spatially separated from each other and each light spot is arranged to illuminate a corresponding sub-area of the replay field within the scene . <EOS>