Test carrier analysis system

In a test carrier analysis system for the analytical determination of a component of a fluid sample comprising:

• test carriers comprising a base layer and test layers fixed thereto;
• said test layers containing a reagent system for reacting with said component to produce a detectable change and including a fluid reservoir layer and a color formation layer, the color formation layer being movably connected to the base layer to move between an initial position wherein the color formation layer is not in fluid contact with the fluid reservoir layer and a second position wherein the color formation layer is pressed against the fluid reservoir layer in fluid-exchange contact therewith,
• and an evaluation apparatus comprising pressure means for pressing the color formation layer against the fluid reservoir layer in fluid-exchanging contact therewith, an optical means for the reflometric determination of the color variation of the color formation layer by a reference measurement, wherein the diffuse reflection of a reference surface is determined, and a sample measurement in which the diffuse reflection of the color formation layer is determined, the improvement comprising the control unit controlling the evaluation apparatus to cause the reference measurement and the sample measurement to be carried out in turn by means of the same optical unit on the color formation layer, the color formation layer also serving as the reference surface, after the color formation layer is pressed against the fluid reservoir layer by the pressure means.