SU911176A1 - Spectrometer - Google Patents

Description

(54) SPECTROMETER

I

The invention relates to a measurement technique and is particularly suitable for photoelectric spectrum recording.

Optical schemes of spectrometers with interference selective amplitude modulation, based on a two-beam interferometer with two separate channels, are known.

However, these devices do not have the stability of the interference pattern, which leads to a decrease in the modulation amplitude.

The closest to the invention according to the technical essence is a spectrometer with an interference selective amplitude modulation with a reverse-circular course of a duchi, containing a polarizer, a beam splitter, two interference-phase gratings, a mirror, a mullor, a compensator and an analyzer in which both interfering beams pass through the same elements of the optical circuit in opposite directions, as a result of which the interference pattern is distinguished by an increased stability and a decrease in the amplitude of the random phase stirovok elements of the optical circuit does not occur

The disadvantages of the known spectrometer are the presence of distortions of the apparatus function, the incomplete use of the resolving power of diffraction gratings, and the effect of the constant composition of the recording radiation.

to

The purpose of the invention is to eliminate distortion of the hardware fraction and the resolution power of the spectrometer.

Delivered yel is reached; the fact that the spectrometer containing along

ts beam polarizer, a beam splitter installed at its entrance, two diffraction gratings, a mirror and a modulator, a polarizer and an analyzer are introduced, the analyzer and the beam splitter are made in the form

Claims (2)

20 polarization grids, with their threads in the light fixture parallel to the strokes of diffraction gratings, the analyzer is set at an angle f. the optical axis 391 after the beam split at the spectrometer output, while the polarizer and the anat chopper are set so that their planes are perpendicularly mutually perpendicular, and the priming plane of the analyzer is hijacked 45 with streaks of diffraction arrays; full cross section of the light beam. The drawing shows an optical spectrometer circuit. The spectrometer contains a polarizer 1, a linear polarization, a polarization grid 2, which is a beam splitter, diffraction gratings 3 and 4, a mirror 5, which make up a circular contour and implement the principle of selective interference, an electro-optical modulator 6, which allows change the path difference, the grid analyzer 7, reducing the oscillations in one plane and dividing the output beam by two. The net beam splitter (anatazator) is made by applying a flat metal layer (by spraying or photographic method) in the form of a grid of threads with a predetermined period on a transparent substrate. The spectrometer works as follows. A parallel tsuchek natural link, the passage through polarizer 1 and turning into linear polarization, falls on the net beam splitter 2, where it is divided into two beams, polarized in two mutually perpendicular planes. These two beams, passing a circular contour consisting of a mirror 5, diffraction gratings 3 and 4, an electro-optical modulator 6 facing each other, the arch of the rf light scatter S in an oahin beam, i 1 Electr optics motor 6, the main directions of which are the electric field coincides with the polarization planes of the forward and reverse beams passing through it, the difference in travel between them changes. The operation of an electro-optic modulator is based on the Pockels effect, in which, in the case of an imposition on a crystal, for example, Gel AS, an electric backside, double refraction penetrates, and the difference between the ordinary and extraordinary rays appears. The grid analyzer 7 reduces the vibrations into one plane, which interfere with each other. In addition, the grid analyzer 7 divides the beam incident on it into two. 6 Due to the perpendicularity of the polarization planes of the analyzer in transmitted and reflected light, the interfering oscillations of the incident O1 radiation; they are called additionally out of phase relative to each other by JT. When using two receivers connected in opposite directions, the difference between the signals produced by the radiation receivers is recorded. In this case, the constant components are subtracted, and the variables are added. In the proposed spectrometer, the hardware function in the process of interference modulation is not distorted even twice as much as in the known, which allows recording of a continuous spectrum, and using a broadband receiving-recording path with full use of the resolution power of diffraction gratings and without phase distortions hardware function. The presence of two output beams, the variable components of the intensities of which are in antiphase, allows the laser to reach the luminosity of the instrument to the luminosity of the wind spectrometer and eliminate the influence of the constant component of these intensities, for example, by using two receivers connected opposite to each other. The invention contains a spectrometer with a beam splitter located along the beam, two diffraction gratings, a mirror, a modulator, which is associated with a polarizer and analyzer with the de-distortion circuit of the instrument function and the resolving power of the spectrometer, and an analyzer and beam splitter made in the form of polarization grids, their threads in the splitter are parallel to the diffraction gratings, the analyzer is installed under the diffractor to the optical axis after the splitter at the output of the spectrometer, while and analyzer polarizers are set so that their polarization planes mutually perpendicular, plane floor and analyzer polarization is an angle of 45 strokes with diffraction gratings formed electrooptic modulator and occupies the full cross section of the light beam. Sources of information taken into account in the examination 1. Manko V. Infrared methods in space research. M., Mir, 1977, p. 324-328. 2. USSR author's certificate N 128393, cl. Gi OIJ S / S, 1961.