The present invention proposes a medical heat exchanger for heating with a light emitter. The heat exchanger disclosed here has at least one fluid chamber having at least one outside wall which forms the fluid chamber with a fluid-tight seal, such that the fluid chamber is configured for receiving and/or conducting the medical fluid and such that the fluid chamber has at least one component, which is configured as a light absorber and is arranged within the fluid chamber in at least some sections so that there is direct contact between the component configured as the light absorber and the medical fluid in at least some sections when receiving and/or conducting the medical fluid and wherein the outside wall of the fluid chamber has at least one light-transmitting section, so that the light emitted by the light emitter can heat the absorber without any local temperature peaks on the medical heat exchanger.
