大家好 小弟第一次在此板發文 不知道是否能在此板請求協助翻譯 若不適合請告知我會把此文刪除 小弟英文程度不佳 原文如下 The advantages besides the lack of moving parts are the quasi-parallel measurement of the whole spectrum, which reduces the measuring time. Further advantages are the robustness and the small dimensions. The Seya-Namioka arrangement is further advantageous because of fewer optical elements, which have to be adjusted. In case of imaging gratings mainly so-called flat field gratings are used. This type of grating offers the advantage of a plane focal line, which can be detected by the plane line array without big imaging errors. Nevertheless, plane grating spectrometers as the Czerny-Turner show improved optical properties because of better compensation possibilities of imaging errors. Usually, the most efficient diffraction order of the grating is detected by the array; the detection of other orders is avoided by design or suppressed by several means (filters, ray traps). One has to say, that array spectrometers show some disadvantages, too: The integral illumination over the full wavelength range increases the stray light, compared with monochromatic set-ups. Furthermore, the sensitivity is lower than of a monochromator, which can even be fitted out with a photo multiplier. The precision and resolution is normally less than that of laboratory instruments with a turnable dispersive element. The first array spectrometers included original gratings, manufactured by holography (interference of a splitted laser beam) or mechanical ruling. Holographic gratings show less stray light because of their better surface quality than those of mechanically proceeded ones. Furthermore, it is possible to produce holographic gratings with reduced imaging errors by a special design of the exposure arrangement. Such master gratings are replicated into epoxy layers (with an aluminium reflexion layer and a protection coating) to reduce the costs of the spectrometer. A further price reduction is obtained with a replication of the master gratings by injection moulding into a plastics material, e.g. PMMA. This technique is useable for less demanding applications because of a deterioration of the optical properties. --

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