摘要:
The invention relates to a spectrometer (10) with a dispersive element (16) that can be displaced between at least two positions. In the first position, the simply dispersed radiation (44) of a selected wavelength is reflected directly back in the incident beam path (42), while in the second position the dispersed radiation (32) of the selected wavelength can be directed to a reflective element (30) that is positioned such that the radiation (34) can be directed at least one more time across the dispersive element (16) and then back to the incident beam path (38). The spectrometer is provided with a device, for example, a mirror, an echelle grating or a prism that deflects the beam from the plane of dispersion, which is arranged in such a manner that the simply dispersed beam (34) runs in another plane than the multiply dispersed beam (36). The mirror (30) is inclined by an axis (54) that extends parallel to the plane of dispersion and perpendicular to the incident beam (32).
摘要:
The invention relates to an Echelle polychromator and can be employed in instruments for the spectrophotometric investigation of radiation sources. It is characterized in that, connected in series with the polychromator, there is a dispersive and polychromatic illuminating device, which is formed from an entrance slit arrangement, collimator optics, prism and camera optics, the entrance slit arrangements of the polychromator and of the illuminating device consisting of a main slit for limiting the bundle in the grating dispersion direction and a transverse slit for limiting the bundle in the direction of the dispersion of the prism in the Echelle polychromator. The whole of the wavelength range, which is to be processed by the polychromator, is imaged completely with negligible aberration on the transverse slit of the Echelle polychromator as a spectrum of the illuminating device. The dispersion of the illuminating device runs in the direction of the transverse dispersion of the prism of the Echelle polychromator. The dispersion-induced geometric width of the spectrum of the illuminating device for the whole of the wavelength region that is to be processed by the polychromator is less than the width of the transverse slit of the Echelle polychromator. Parts of the bundle of rays of the spectrum of the illuminating device are blocked out by the transverse slit of the Echelle polychromator.
摘要:
The invention relates to an arrangement and method for multielement analyse of chemical elements in which light cables are used to transmit spectral lines or bands produced by an optical dispersion means from a sample material radiation to an array of photodetectors. The light cable end-portions are inserted as many as required for a definite analyzing program into holes of a plug-in unit and are associated via a mask to definite photodetectors. The plug-in unit is displaceable relative to the mask so that the spectral informations from definite light cables associated to definite spectral lines or bands are evaluated in groups which require similar or equal excitation conditions. The latter are adjustable by respective means.
摘要:
The invention relates to an optical system for spectral analysis devices particularly for use in atomic emission spectroscopy in which the aberrations, astigmatis and coma are compensated separately, comprising two concave spherical reflectors adjacently arranged and having their vertices equidistantly located relative to a center of a dispersing member. The latter has a dispersion plane at right angles to the dispersing structure of the dispersing member and to its surface, the vertices are located in said dispersion plane. The center beams originating from an excitation light source are reflected at the reflectors in reflection planes which are at right angles to the dispersion plane. The light entrance of the optical system comprises two slits the images of which coincide in a focal plane. The center of the focal plane and the light entrance have a same distance to the dispersion plane and are located on different sides of the latter.
摘要:
An Echelle spectrometer arrangement (10) with internal order separation contains an Echelle grating (34) and a dispersing element (38) for order separation so that a two-dimensional spectrum having a plurality of separate orders (56) can be generated, an imagine optical system (18, 22, 28, 46), a flat-panel detector (16), and predispersion means (20) for predispersing the radiation into the direction of traverse dispersion of the dispersion element (38). The arrangement is characterized in that the predispersion means (20) comprise a predispersion element which is arranged along the optical path behind the inlet spacing (12) inside the spectrometer arrangement. The imaging optical system is designed in such a manner that the predispersed radiation can be imaged onto an additional image plane (24) which does not have any boundaries in the predispersion direction and which is arranged along the optical path between the predispersion element (20) and the echelle grating (34). Optical means (20, 68) in the area of the predispersed spectrum are arranged to influence the spatial and/or the spectral beam density distribution on the detector (16).
摘要:
The invention relates to a spectrometer arrangement (10) having a spectrometer for producing a spectrum of radiation from a radiation source on a detector (34), comprising an optical imaging Littrow arrangement (18, 20) for imaging the radiation entering the spectrometer arrangement (16) in an image plane, a first dispersion arrangement (28, 30) for the spectral decomposition of a first wavelength range of the radiation entering the spectrometer arrangement, a second dispersion arrangement (58, 60) for the spectral decomposition of a second wavelength range of the radiation entering the spectrometer arrangement, and a common detector (34) arranged in the image plane of the imagine optics, characterized in that the imaging optical arrangement (18, 20) comprises an element (20) that can be moved between two positions (20, 50), wherein the radiation entering the spectrometer arrangement in the first position is guided via the first dispersion arrangement and in the second position via the second dispersion arrangement.
摘要:
A method for the wavelength calibration of echelle spectra, in which the wavelengths are distributed across number of orders is characterised by the steps: recording of a line-rich reference spectrum with known wavelengths for a number of the lines, determination of the position of a number of peaks of the reference spectrum in the recorded spectrum, selection of at least two first lines of known order, position and wavelength, determination of a wavelength scale for the order in which the known lines lie, by means of a fit function γm(x), determination of a provisional wavelength scale γ?m 1(x) for at least one neighboring order m 1, by means of addition/subtraction of a wavelength difference γFSR which corresponds to a free spectral region, according to γm 1 ?(x)=γm(x)γFSR with γFSR=γm(x)/m, determination of the wavelengths of lines in said neighboring order m 1, by means of the provisional wavelength scale γ 1(x), replacement of the provisional wavelength of at least two lines by the reference wavelength for said lines as obtained in step (a) and repeat of steps (d) to (g) for at least one further neighboring order.
摘要:
A spectrometer assembly (10) is disclosed. The assembly includes a light source (11) with a continuous spectrum. A pre-monochromator (2) generates a spectrum with a relatively small linear dispersion from which a spectral portion is selectable, the spectral bandwidth of the spectral portion being smaller than or equal to the bandwidth of the free spectral range of the order in the echelle spectrum. The centre wavelength of the selected spectral interval is measurable with maximum blaze efficiency. The assembly also includes an echelle spectrometer (4) with means for wavelength calibration, an entrance slit (21) at the pre-monochromator (2), an intermediate slit assembly (50) with an intermediate slit (3) and a spatially resolving light detector (5) in the exit plane of the spectrometer for the detection of wavelength spectra.
摘要:
An Echelle polychromator 50 has disposed upstream thereof a pre-monochromator 14 comprising a prism 20. The linear dispersion of the pre-monochromator 14 is variable by varying the angular dispersion of the prism 20. A particular spectral position and the close vicinity thereof are analyzed by an Echelle grating 54 with high resolution. Care must be taken that, on the one hand, the detector array 66 of the Echelle polychromator 50 is fully exploited in response to the central wavelength respectively observed and that, on the other hand, interfering orders are kept away from the Echelle polychromator 50. The linear dispersion of the pre-monochromator is variable for this purpose.
摘要:
An adjustable Echelle spectrometer arrangement which can be used in single- and multi-element analysis by the emission or absorption of optical radiation. To compensate all the manufacturing and setup errors, the only arrangements present are those to change the height of the entry slit arrangement above the base plate and to rotate the dispersion prism about a first axis, approximately parallel to its roof edge, and about a second axis, that is vertical thereto. This compensates for the effect of errors associated with component and setup parameters which results from greater tolerances, without impairing mechanical and thermal stability and imaging quality.