Patent ID: 8759081

Claim:
A test element for use with an analytical unit with an optical emitter to emit light for the optical analysis of a fluid sample, comprising: a substrate and a microfluidic channel structure that is enclosed by the substrate and a cover layer, wherein the channel structure comprises a measuring chamber with at least one inlet opening; the test element has a first level, which faces the cover layer and in which the optical analysis of the fluid sample is carried out, and a second level, which interconnects with the first level in such a manner that the first level is disposed between the cover layer and the second level; a part of the measuring chamber that extends through the first level forms a measuring zone that connects to a part of the measuring chamber extending at least in part into the second level that constitutes a mixing zone, wherein the mixing zone of the measuring chamber contains a reagent for detecting an analyte in the fluid sample that reacts with the fluid sample; the mixing zone disposed in the second level has a rounded floor; two optical deflection devices are disposed in the first level by means of which, for the optical analysis of the fluid sample, light incident upon the test element is deflected such that the light is deflected through the first level essentially parallel to the cover layer and traverses the measuring zone of the measuring chamber along an optical axis; and the incident light is deflected parallel to the cover layer by means of the first deflection device and is guided out of the test element by means of the second deflection device.