Operating spectrometer beyond optics correction range - by adjusting optics spacings to maintain optimal sensitivity

摘要

A process is claimed for operating a spectrometer over a wavelength range greater than that for which its imaging optics are corrected, the spectrometer having an illuminating beam path for uniform illumination of a predetermined region of an object in the object plane, an observation beam path for producing an intermediate image of the illuminated region in an intermediate image plane in which is located a measurement aperture in front of a sensor, and a monochromator mounted in one or each beam path. The novelty is that, depending on the wavelength selected by means of the monochromator (2), (a) the mutual spacings of the optical elements in the observation beam path are modified so that a sharp intermediate image is produced in the intermediate image plane or a conjugate plane; and/or (b) the mutual spacings of the optical elements in the illuminating beam path are modified so that for any selected wavelength, the same optical beam path is retained through these elements. ADVANTAGE - The process maintains optimal sensitivity of the spectrometer.