SU593081A1 - Interference spectrometer - Google Patents

Description

both in the rays that pass through the interference part of the spectrometer, not reflected from mirrors 7 and 9, and in the rays that are emitted from these mirrors. Interference rings in the plane of the diaphragms 3 and 12 are observed only in the rays that are not reflected from mirrors 7 and 9. For the other rays, the contrast of the interference pattern is zero due to the wedge introduced by the slope of these mirrors, since the lower part of the spectrometer is only a beam-splitting scheme, and not an interferometer with reverse ray path. With lenses 13 and 15, the diaphragm 3 and 12 are projected onto the plane of the mirror chopper 16, which alternately directs the fluxes F and Fg emerging from these diaphragms, respectively, the photodetector 18. The attenuator 14 compensates for the losses in the reflection of the light beams by the chopper 16.

With differential registration, the amplified signal from the photodetector corresponds to the difference of the light fluxes Ф: and Ф2. In this spectrometer, precise scaling of the background light fluxes is necessary, i.e., the energy balance of the light beams incident on the photodetector.

Each of the compared streams alternately falling on the photodetector consists of two spatially non-coincident beams (in the instrument plane), one of which is interfering radiation in the resolvable spectral Hii interval with a DF background /, and the second beam, which corresponds to the radiation reflected from mirrors 7 and I am only von DF; -

The background luminous flux going out to the receiver side through aperture 5 is equal to

F | AF 4-DF;

Df {NKI K2 2RT (S-S,) (2)

DF2 ./Sz (+ P) .Sb (3)

The flow through the diaphragm 12 is equal to

F DFKDF |

 . K2 (K + T) (S-S) NKl K3-2RT Sb

total area of light beams in the pupil of the device; the area of the beam reflected from mirrors 7 and 9; reflection coefficients and

. transmission of the beam splitter; / reflection coefficient of the mirror, la 8; mirror reflection coefficient

7 and 9;

normalization factor depending on the luminance source, the area of the diaphragms. 3 and 12, transmit the rest of the spectrometer.

the new light fluxes: contribute to measurement,

f, v. / Cf (R-T) Kg -Si-,: K2 (S-S,) (7)

TO.,

with S | five

(eight)

K., -I- K.

Since mirrors 7, S and 9 have selective selective coatings, Kz n / Cs does not depend on the wavelength of the spectrometer tuning, and if the condition (8) is fulfilled in one part of the spectrum, the balance of light flux will not be disturbed as the instrument is rearranged.

Claims (3)

1.Fellgett R. Journ. Phys. Radium, 19, 1958, p. 237. 2. Collection of theses of the Soviet-French symposium on optical spectral instruments (3) and devices for image processing, Moscow, 1976, p. 15. 3. Optical-mechanical industry (6) I 11, 1974, p. 70 sixteen 13