| 摘要 |
A spectrometer is provided having a carrier, a light input for measurement light disposed on the carrier, a diffraction grating disposed on the carrier for dispersing the measurement light received from the light input, an opto-electronic detector disposed on the carrier for receiving and detecting the measurement light dispersed by the diffraction grating, at least one optical component for imaging the measurement light on the detector through the diffraction grating, a base board fastened to said carrier for supporting the opto-electronic detector, wherein the opto-electronic detector is fastened at a predetermined position on the base board, and wherein the base board and the carrier include positioning members for relatively positioning the base board on the carrier in a predetermined position. Preferably, the detector is a detector chip excluding a housing and fastened in a predetermined position on the base board. Both, carrier and base board have cooperating positioning members for positioning the base board on the carrier. The base board is preferably an electronic circuit board being fastened to the carrier in such a manner so as to allow a thermal expansion, and wherein the position of the fastening point P relative to the position of the detector on the base board is chosen such that the thermal expansion of the base board substantially compensates the drift of the spectral light component relative to the detector for at least an intermediate wavelength of the measured spectrum, the drift being caused by the thermal expansion of the diffraction grating and the carrier. In addition, the materials of the carrier, the base board, and the diffraction grating are selected with respect to their thermal expansion coefficients such that the temperature drift of the spectrum is substantially compensated for the entire measured spectrum. For most applications, the spectrometer is also sufficiently temperature compensated when using plastic components and is easily and economically produced.
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