Coarse and fine projective optical metrology system

Described herein is a projective optical metrology system including: a light target (2) formed by a first number of light sources (4a-4c) having a pre-set spatial arrangement; and an optical unit (6) including an optoelectronic image sensor (10), which receives a light signal (R 1 , R 2 ) coming from the light target (2) and defines two different optical paths for the light signal towards the optoelectronic image sensor (10). The two optical paths are such that the light signal forms on the optoelectronic image sensor at most an image (I 1 ;I 2 ) of the light target that can be processed for determining at least one quantity indicating the mutual arrangement between the light target and the optical unit.