Multiwavelength readhead for use in the determination of analytes in body fluids

一种用于样品中的分析物浓度测定的读取头，包括用于接收样品的读取区；包含用于输出在多个波长上的光的多个发光元件的光源；具有输入端和输出端的光导管；用于接收来自光导管输出端的光，并用基本平行光束照明样品的透镜；和用于检测响应照明样品的来自样品的光的检测器。与光源光学连接的光导管输入端用来接收多个发光元件输出的光。光导管的输入端具有从多个光学元件中的至少一个的中心偏移的中心。光导管引导从光源接收的光的大部分到光导管输出端。 A readhead (10) for use in the determination of the concentration of an analyte in a sample comprises a read area (30) for receiving the sample, a light source (12) including a plurality light emitting elements for outputting light at a plurality of wavelengths such as a multiwavelength surface mount light emitting diode (SMD LED), a light guide (16) having an input end and an output end (18), a lens (22) for receiving light from the output end (18) of the light guide and for illuminating the sample with a substantially collimated beam of light (26), and a detector (34) for detecting light (36) from the sample in response to illuminating the sample. The input end of the light guide (16) being optically coupled to the light source (12) for receiving light output by the plurality of light emitting elements. The input end of the light guide (16) has a center that is offset from the center of at least one of the plurality of light elements. The light guide (16) guides a substantial portion of the light received from the light source to the output end of the light guide. An acrylic light guide (16) having a square cross-section creates an even illumination distribution for each wavelength at the output end (18) of the light guide (16) even though LED dies of an SMD LED are offset from the center of the light guide (16).