A device for observing a sample comprising: - a holder, intended to hold the sample; - a first light source, configured to emit an incident light wave that propagates to the sample; - a first image sensor, configured to acquire, in a first mode, a first image ( I 1) of the sample illuminated by the incident light wave, the holder being configured to hold the sample between the first light source and the first image sensor in such a way that no magnifying optics are placed between the sample and the first image sensor, the first image sensor being exposed to a light wave called the exposure light wave, the first image ( I 1) defining a first field of observation (Ω 1) of the sample; the device also comprising: - a second image sensor, which is different from the first image sensor, optically coupled to an optical system having a magnification higher than 1, so as to acquire, in a second mode, a second image ( I 2) of the sample, held on the holder, in a second field of observation (Ω 2) that is smaller than the first field of observation (Ω 1), the optical system being arranged between the sample and the second image sensor, and being configured to form, in the second mode, an image of the sample on the second image sensor; - a mechanism for moving the sample relative to the first image sensor and to the optical system, so as to alternate between: ▪ the first mode, in which the sample is placed in the field of observation (Ω 1) of the first image sensor, so as to acquire the first image ( I 1); ▪ the second mode, in which the sample is placed in the field of observation (Ω 2) of the second image sensor, so as to acquire the second image ( I 2). - a holder, intended to hold the sample; - a first light source, configured to emit an incident light wave that propagates to the sample; - a first image sensor, configured to acquire, in a first mode, a first image ( I 1) of the sample illuminated by the incident light wave, the holder being configured to hold the sample between the first light source and the first image sensor in such a way that no magnifying optics are placed between the sample and the first image sensor, the first image sensor being exposed to a light wave called the exposure light wave, the first image ( I 1) defining a first field of observation (Ω 1) of the sample; - a second image sensor, which is different from the first image sensor, optically coupled to an optical system having a magnification higher than 1, so as to acquire, in a second mode, a second image ( I 2) of the sample, held on the holder, in a second field of observation (Ω 2) that is smaller than the first field of observation (Ω 1), the optical system being arranged between the sample and the second image sensor, and being configured to form, in the second mode, an image of the sample on the second image sensor; - a mechanism for moving the sample relative to the first image sensor and to the optical system, so as to alternate between: ▪ the first mode, in which the sample is placed in the field of observation (Ω 1) of the first image sensor, so as to acquire the first image ( I 1); ▪ the second mode, in which the sample is placed in the field of observation (Ω 2) of the second image sensor, so as to acquire the second image ( I 2). ▪ the first mode, in which the sample is placed in the field of observation (Ω 1) of the first image sensor, so as to acquire the first image ( I 1); ▪ the second mode, in which the sample is placed in the field of observation (Ω 2) of the second image sensor, so as to acquire the second image ( I 2).