Abstract: The invention relates to a device for scanning still images as applicable in particular to high-definition television (HDTV) systems. In accordance with customary practice, the entire still image is converted by an optical system having an oscillating mirror to an image which passes in front of a linear sensor having photosensitive elements. Diffusion of the optical system causes detachment of dark areas which are adjacent to bright areas. In order to prevent this detachment, the movement of a shutter provided with slits is synchronized with the movement of the mirror so as to occult part of the image which passes in front of the sensor, thus leaving only the zone located at the level of the sensor.