A device for line-scanning optical coherence tomographic microscopy, comprising: a spectrally broadband light source; a sensor with a one-dimensional sensing surface; an interferometric microscope comprising a reference arm, at the end of which is arranged a reflecting reference surface, an object arm configured to receive an object to be imaged, a beam splitter coupling said object arm and reference arm to said light source and to said sensor, and at least a first microscope objective arranged on said object arm; a one-dimensional confocal spatial filtering device (212, 213) configured to interact with said light source in order to illuminate said object along a focal line located in an object space of said first microscope objective, and configured to select the light backscattered by said object and coming from said focal line, so as to form a one-dimensional image of said focal line on the detection surface; a device (235, 237) for unidirectional scanning of said focal line comprising a reflecting surface and means for rotating the reflecting surface along an axis of rotation substantially perpendicular to an optical axis (z) of the first microscope objective, said reflective surface being arranged on said object arm, upstream of said first microscope objective, such that the object arm does not include any optical element for the optical conjugation of the reflecting surface and an entrance pupil of the first microscope ojective, the device for unidirectional scanning being configured to scan the focal line in a lateral direction (y) substantially perpendicular to the optical axis (z) of said first microscope objective; a processing unit configured to produce at least one two-dimensional tomographic en-face image of said object to be observed, arranged in a plane (x, y) substantially perpendicular to said optical axis of the microscope objective, from a plurality of one-dimensional interferometric images of the object that are produced by the interferometric microscope for different positions of said focal line during said unidirectional scanning and are acquired by said sensor. a spectrally broadband light source; a sensor with a one-dimensional sensing surface; an interferometric microscope comprising a reference arm, at the end of which is arranged a reflecting reference surface, an object arm configured to receive an object to be imaged, a beam splitter coupling said object arm and reference arm to said light source and to said sensor, and at least a first microscope objective arranged on said object arm; a one-dimensional confocal spatial filtering device (212, 213) configured to interact with said light source in order to illuminate said object along a focal line located in an object space of said first microscope objective, and configured to select the light backscattered by said object and coming from said focal line, so as to form a one-dimensional image of said focal line on the detection surface; a device (235, 237) for unidirectional scanning of said focal line comprising a reflecting surface and means for rotating the reflecting surface along an axis of rotation substantially perpendicular to an optical axis (z) of the first microscope objective, said reflective surface being arranged on said object arm, upstream of said first microscope objective, such that the object arm does not include any optical element for the optical conjugation of the reflecting surface and an entrance pupil of the first microscope ojective, the device for unidirectional scanning being configured to scan the focal line in a lateral direction (y) substantially perpendicular to the optical axis (z) of said first microscope objective; a processing unit configured to produce at least one two-dimensional tomographic en-face image of said object to be observed, arranged in a plane (x, y) substantially perpendicular to said optical axis of the microscope objective, from a plurality of one-dimensional interferometric images of the object that are produced by the interferometric microscope for different positions of said focal line during said unidirectional scanning and are acquired by said sensor.