Device for observing an object, present in a sample, comprising: - a holder, able to receive the sample, the holder defining a plane, called the sample plane, in which the sample lies when it is placed on the holder; - a light source, able to emit a light beam, called the incident light beam, in order to illuminate the object; - an image sensor, for acquiring an image representative of radiation back scattered by the object under the effect of an illumination by the incident light beam; - a screen, lying facing the holder, so as to be exposed to radiation back scattered by the object when the latter is illuminated by the incident light beam, so as to form, on the screen, an image (I 20), called a scattergram, representative of said back-scattered radiation; - the screen comprising a first face (20 1) exposed to the back-scattered radiation, the area of the first face being larger than 100 cm 2; - the image sensor being configured to acquire an image (I 30) of the scattergram formed on the screen; the device also comprising a reflective element, which is placed between the screen and the object, and which is able to reflect a portion of the incident light beam along an axis of incidence perpendicular or substantially perpendicular to the plane of the sample, the reflective element being securely fastened to the first face (20 1) of the screen; the device being characterized in that it comprises a binding medium lying between the reflective element and the screen, the binding medium allowing the reflective element to be fastened to the screen, the device being such that the reflective element and/or the binding medium are configured to absorb at least 50% of the back-scattered radiation propagating between the object and the screen. - a holder, able to receive the sample, the holder defining a plane, called the sample plane, in which the sample lies when it is placed on the holder; - a light source, able to emit a light beam, called the incident light beam, in order to illuminate the object; - an image sensor, for acquiring an image representative of radiation back scattered by the object under the effect of an illumination by the incident light beam; - a screen, lying facing the holder, so as to be exposed to radiation back scattered by the object when the latter is illuminated by the incident light beam, so as to form, on the screen, an image (I 20), called a scattergram, representative of said back-scattered radiation; - the screen comprising a first face (20 1) exposed to the back-scattered radiation, the area of the first face being larger than 100 cm 2; - the image sensor being configured to acquire an image (I 30) of the scattergram formed on the screen; the device also comprising a reflective element, which is placed between the screen and the object, and which is able to reflect a portion of the incident light beam along an axis of incidence perpendicular or substantially perpendicular to the plane of the sample, the reflective element being securely fastened to the first face (20 1) of the screen; the device being characterized in that it comprises a binding medium lying between the reflective element and the screen, the binding medium allowing the reflective element to be fastened to the screen, the device being such that the reflective element and/or the binding medium are configured to absorb at least 50% of the back-scattered radiation propagating between the object and the screen. the device also comprising a reflective element, which is placed between the screen and the object, and which is able to reflect a portion of the incident light beam along an axis of incidence perpendicular or substantially perpendicular to the plane of the sample, the reflective element being securely fastened to the first face (20 1) of the screen; the device being characterized in that it comprises a binding medium lying between the reflective element and the screen, the binding medium allowing the reflective element to be fastened to the screen, the device being such that the reflective element and/or the binding medium are configured to absorb at least 50% of the back-scattered radiation propagating between the object and the screen.