Abstract: In an optical fittering device comprising at least two fitters, the first filter (EF1) is tilted by an angle of incidence whose value is adjusted to bring the cut-off limit of the first filter (EF1) closer to one of the sides of the line of the illumination beam (FLA), which reduces the optical density of the first filter, while the association in series of the first (EF1) and second (EF2) filters enables to obtain a high-pass filtering whose global density corresponds to the sum of the densities of the first and second filters and whose cut-off limit is lower than that obtained by a single filter tilted to its optimum angle. A third filter (EF3) mounted in parallel with respect to the first and second filters (EF1 and EF2) enables to obtain, at the level of the common collection path (TCC), a band eliminating filtering whose cut-off limits are positioned on either side of the illumination line with a view to an optimum analysis of the low frequency lines.

Abstract: The spectrometry apparatus of the present invention includes, in addition to conventional analysis, a first diaphragm having a first chosen variable aperture for spatially filtering a coherent-excitation beam. The apparatus also includes a first deflector stage (DF1) for sweeping an excitation beam over a sample according to a first chosen deflection. Additionally, there is included a second diaphragm having a second variable aperture conjugate with the first aperture for filtering the incoherent-scattering beam. The spectrometry apparatus further provides a second deflector stage placed downstream in order to sweep the spectral image of the incoherent-scattering beam thus filtered over the multichannel detection module according to a second chosen deflection.

Abstract: A sample which is exposed to excitation radiation scatters light to a separator filter. The scattered light includes a Raman spectrum. The separator filter reflects, a spectral band of the radiation which it receives and transmits, the remainder of the radiation which it receives. The reflected spectral band is centered on the excitation radiation. The spectral band is collected and guided to a band-eliminating filter in order to eliminate therefrom a spectral band which is narrower than the reflected spectral band, and which embraces the wavelength of the excitation radiation. The band-eliminating filter has a steep elimination slope. A signal corresponding to the reflected spectral band, from which the narrow band has been eliminated in this way, is combined with the radiation transmitted by the separator filter and the combined radiations are supplied to a detection and analysis unit.

Abstract: The filtration means filter the exciter radiation (EX) in a first forward direction from generator means (LS) to the specimen (EC), by allowing a second spectral band (BZ) of predetermined spectral width (l) and centered on a selected frequency corresponding to the wavelength of the exciter radiation (L0) to pass and stopping a first spectral band (FZ) complementary to the second spectral band (BZ), while substantially simultaneously with this first filtration operation, these filtration means further filter the analysis radiation (ON) in a second direction that is the reverse of the first direction, by allowing the first spectral band (FZ) to pass and stopping the second spectral band (BZ).

Abstract: The invention relates to a spectrometry installation comprising an inlet, optical fiber means suitable for receiving an inlet beam and delivering a spectrally dispersed image of the beam which image is limited to a selected spectral band, a multi-channel detection module receiving said spectral image, and processor means. The optical filter means are provided with a deflector stage. Control means are associated with the optical deflector means to define the spectral band in terms of center frequency and band width, and control means are associated therewith for displacing the spectral image over the detection module. An electronic control unit is provided to control the control means and to control the processor means in a plurality of operating modes, each of which comprises joint control of the selected spectral band, of the displacement of the spectral image, and of the processor means, for the purpose of selectively using a particular set of detector components.