Device and method for analyzing samples

A device for determining parameters of a fluid-containing sample, the device being implemented to be introduced into in a system for individually irradiating samples with light of a light source, which emits light in direction of an optical axis that extends in an essentially vertical direction, this system including a detector for measuring the light coming from a single sample, and this detector having a detection direction that lies on an optical axis, which is essentially parallel to the optical axis of the light source, and the device including at least one reflective surface implemented to deflect the light of the light source into an essentially horizontal irradiation direction for irradiating the sample, wherein the detection direction of the detector is positioned offset to the optical axis of the light source in such a way that only the light coming from the individual sample, but not the light emitted by the light source or deflected by the reflective surface, roaches the detector, wherein the system includes an essentially horizontal carrier with an opening for microplates, and wherein the device has the dimensions of a standard microplate and includes a mirror having the reflective surface and a support surface assigned to the mirror for placing a cuvette containing a sample, the device including an opening in the region of the support surface for passage of light triggered in the sample or reflected by the sample to the detector.