An apparatus for extracorporeal blood treatment, in particular a dialysis machine, comprising a body for accommodating operational components for the extracorporeal blood treatment, and wherein a monitor unit which is adapted to be non-orientable or at least to be non-tiltable relative to the body and includes a display unit , wherein the monitor unit includes a display content representation influencing device which is arranged to influence the visibility of information represented on the display unit, and the display unit is arranged to simultaneously display at least two different display contents; characterized in that the display content representation influencing device comprises an antireflection coating means disposed on a display surface of the display unit which is arranged to coat at least a portion of the display surface, the display content representation influencing device further comprises a silvering means disposed on the display surface of the display unit which is arranged to silver at least a portion of the display surface, the display content representation influencing device is arranged to influence the visibility of the at least two display contents simultaneously represented on the display unit so that from a first viewing direction and/or a first distance of a first user (A) to/from the first display unit one of the at least two display contents is visible and from a second viewing direction and/or a second distance of a second user (B) to/from the display unit another one of the at least two display contents is visible, wherein the display content representation influencing device is a filter adapted to be electronically controlled for changing its light transmission properties, wherein the filter is configured as a parallax barrier. wherein a monitor unit which is adapted to be non-orientable or at least to be non-tiltable relative to the body and includes a display unit , wherein the monitor unit includes a display content representation influencing device which is arranged to influence the visibility of information represented on the display unit, and the display unit is arranged to simultaneously display at least two different display contents; characterized in that the display content representation influencing device comprises an antireflection coating means disposed on a display surface of the display unit which is arranged to coat at least a portion of the display surface, the display content representation influencing device further comprises a silvering means disposed on the display surface of the display unit which is arranged to silver at least a portion of the display surface, the display content representation influencing device is arranged to influence the visibility of the at least two display contents simultaneously represented on the display unit so that from a first viewing direction and/or a first distance of a first user (A) to/from the first display unit one of the at least two display contents is visible and from a second viewing direction and/or a second distance of a second user (B) to/from the display unit another one of the at least two display contents is visible, wherein the display content representation influencing device is a filter adapted to be electronically controlled for changing its light transmission properties, wherein the filter is configured as a parallax barrier. <EOS>