SU673864A1 - Diffraction spectrograph - Google Patents

Description

(54) DIGITAL SPECTROGRAPH

I

The invention relates to the field of spectral instrumentation and can be used in the development of spectrographs and monochromators.

Known diffraction spectrographs and monochromatic tori, built on a vertical symmetric circuit 1,

The closest technical solution to the present invention is a diffraction spectrograph, universal in dispersion, constructed according to a vertical symmetric scheme

The disadvantages of this type of spectrographs include the complexity of the design associated with the need to use interchangeable gratings and the impossibility of obtaining a high-intensity spectrum in different orders of the same grating.

The aim of the image is to simplify the design of the spectrograph by using the same diffraction grating to obtain high intensity diffracted radiation in the beam.

In other words, the range of diffraction angles and registration of the studied spectral region in different orders of the spectrum at different linear dispersions.

This is achieved due to the fact that the diffraction grating of the proposed spectrograph has rectangular bars with two working mirror edges and is set so that the angle f between the projection of the incident beam onto the plane perpendicular to the grating lines and the normal to the grating satisfies the relations St m -8j for the right and left spectral orders, respectively, where Sj and rf are the light angles

5 ka lattice.

FIG. Figure 1 shows one of the options for constructing the proposed spectrograph; in fig. 2 — diffraction grating with a rectangular groove profile,

0 both faces are mirrored.

The spectrograph contains an entrance slit 1 located in the focus of the lens.

the collimator 2, the diffraction grating 3, the focusing lens 4 and the photographic plate 5. The projection of the incident beam onto the plane perpendicular to the grating grooves is normal to the grating yrontfjc j and j are the grating brightness angles.

The spectrograph works as follows.

The entrance slit 1 is illuminated by the investigated radiation, which, after the objective of the collimator 2, hits the diffraction grating 3. On the array there is a sequential specular reflection of radiation from each of the two faces of the strokes. The angle between the z lines of the strokes is 90 ° C, so the axis of the beam reflected from the array coincides with the direction from the center of the grid to the center of the camera lens for any angles / within the specified limits. By rotating the diffraction grating around the axis lying: In the plane of the grooves and parallel to them, the required wavelength range and spectral order are established on the photographic plate. that the radiation incident on it is successively reflected from each of the two mirror edges of the grating grooves, works as an angular reflector and makes it possible to combine the direction of the mirror reflection from the grating, corresponding to the maximum energy of the diffracted radiation, with a direction from the center of the grating to the center of the camera lens DD of any diffraction angles in the intervals, to 0-8, where are the light angles of the grating.

When consistently reflecting from each of the two faces of the Strokes in brilliance, any length can be obtained.

waves in k "YuM order,

satisfying relationship

K to

for right and left orders, respectively, where Ы is the lattice constant.

As a result, the region of wavelengths that can. to be obtained with a high intensity, it expands significantly, which makes it possible to record a given spectral region at different diffraction angles in different orders of the spectrum, i.e. to obtain spectra with different linear dispersion. A dispersion universally universal spectrograph with one such grating is equivalent to a spectrograph with a set of gratings whose light angles change 0-S.

and about-.,.

with within

fn

Claims (2)

1. Paysakhson I. V. Optics of spectral instruments. 2nd iad. L., Mashinostroevoe 1975j with. 127. 2. Tarasov KI Spectral devices. L. Mechanical Engineering, 1968, with. 175-176.