Blood treatment machine for extracorporeal blood treatment and system for recognizing blood or blood constituents in a tubing line

A medical system for optically detecting at least one blood constituent in a tubing line at a blood treatment machine for extracorporeal blood treatment, the medical system comprising:

• the blood treatment machine for extracorporeal blood treatment, the blood treatment machine comprising:
• a machine housing,
• electrically conductive shielding against electromagnetic radiation that at least partly shields an inside region of the electrically conductive shielding from electromagnetic radiation from an outside region of the electrically conductive shielding,
• a tubing receptacle apparatus arranged on the outside region of the electrically conductive shielding, the tubing receptacle apparatus comprising a tubing receptacle region configured for a reversible, holding reception of a tubing portion of a medical tubing line,
• a first light guide configured as an illumination source leading to the tubing receptacle region, the first guide light comprising a first end portion and a second end portion,
• a second light guide comprising a third end portion and a fourth end portion, the second light guide being present in addition to the first light guide and being configured as light guide leading away from the tubing receptacle region for the purpose of transmitting light that emerges from the tubing portion, and
• an aperture region in the electrically conductive shielding against electromagnetic radiation, the first light guide and the second light guide being led from the outside region to the inside region of the electrically conductive shielding through the aperture region;
• an electronic measuring apparatus arranged in the inside region of the electrically conductive shielding, the electronic measuring apparatus comprising:
• an electrical light source that emits light into the first light guide, and
• an optical sensor that receives light emerging from the second light guide.