An optical characterisation system for a zone of interest of an object of a scene, comprising: - a selection module comprising: - a matrix detector and an imaging optics which produces an image of the scene on the matrix detector via an initial beam (Bi), - a micro-mirror matrix and a first separating plate which is arranged on an optical path of the initial beam, the micro-mirror matrix and the separating plate being arranged so that the imaging optics simultaneously images the scene on the micro-mirror matrix and the matrix detector, - a processing and control unit which is configured to process the image of the scene (ImS) generated by the matrix detector to select the zone of interest of the object in the image of the scene generated by the matrix detector and to selectively activate the micro-mirrors of the matrix comprised in the zone of interest, - an analysis module comprising: - an optical collection device which is coupled to the micro-mirror matrix and which is configured to collect a beam of interest (Br) reflected by the activated micro-mirrors, - at least one characterisation device which is configured to recover the beam of interest and to characterise the zone of interest based on the beam of interest (Br). - a selection module comprising: - a matrix detector and an imaging optics which produces an image of the scene on the matrix detector via an initial beam (Bi), - a micro-mirror matrix and a first separating plate which is arranged on an optical path of the initial beam, the micro-mirror matrix and the separating plate being arranged so that the imaging optics simultaneously images the scene on the micro-mirror matrix and the matrix detector, - a processing and control unit which is configured to process the image of the scene (ImS) generated by the matrix detector to select the zone of interest of the object in the image of the scene generated by the matrix detector and to selectively activate the micro-mirrors of the matrix comprised in the zone of interest, - a matrix detector and an imaging optics which produces an image of the scene on the matrix detector via an initial beam (Bi), - a micro-mirror matrix and a first separating plate which is arranged on an optical path of the initial beam, the micro-mirror matrix and the separating plate being arranged so that the imaging optics simultaneously images the scene on the micro-mirror matrix and the matrix detector, - a processing and control unit which is configured to process the image of the scene (ImS) generated by the matrix detector to select the zone of interest of the object in the image of the scene generated by the matrix detector and to selectively activate the micro-mirrors of the matrix comprised in the zone of interest, - an analysis module comprising: - an optical collection device which is coupled to the micro-mirror matrix and which is configured to collect a beam of interest (Br) reflected by the activated micro-mirrors, - at least one characterisation device which is configured to recover the beam of interest and to characterise the zone of interest based on the beam of interest (Br). - an optical collection device which is coupled to the micro-mirror matrix and which is configured to collect a beam of interest (Br) reflected by the activated micro-mirrors, - at least one characterisation device which is configured to recover the beam of interest and to characterise the zone of interest based on the beam of interest (Br).