SU1509798A1 - Optical system for illuminating inlet aperture of spectrum device - Google Patents

Abstract

The invention relates to optical instrumentation and can be used in spectrophotometer illuminators. The purpose of the invention is to increase the stability of the lighting when working on different parts of the spectrum. When moving to another part of the spectrum, the projection lens 2, the diaphragm 3, collective 4, collector 5 and condenser 7 lenses move along the optical axis, and the concave corner reflector 12 is perpendicular to the optical axis of the system. With a fixed light source 1, a convex corner reflector 11 and an anti-vascular lens 9, the mating of the optical components is preserved. The movement of each component is proportional to the rotation of the common kinematic connection shaft. 1 s., 2 s. P. f-ly, 3 ill.

Description

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The invention relates to spectral instrumentation and can be used in the design of spectrophotometer illuminators.

The aim of the invention is to increase the stability of the illumination when working in different parts of the spectrum.

FIG. 1 shows the principal optical layout of the optical system; Fig. 2 is a kinematic system diagram;} Fig. 3 shows a kinematic diagram of a drive of a concave corner reflector.

The optical scheme of the system (Fig. 1) contains a source of light 1, a projection lens 2, a diaphragm 3 with a collective lysis 4 located near it, a collector convex-flat lens 5 with it applied on its back. flat surface first raster 6, condenser; a flat-convex lens 7 with a second raster deposited on its front flat surface and an anti-Viettiou lens 9 located directly in front of the entrance slit 10 of the spectral instrument. The lenses in each of the rasters 6 and 8 are the same, their optical axes are parallel to the optical axis of the system and the number of them in rasters is the same. All lenses, except lens 9, are made of the same material (quartz), and the spectral dependences of the change in the refractive index of the lens material 9 (fluorite) and the material of the other lenses coincide with the accuracy of a constant multiplier. A system with variable optical distortion is established between lens 2 and diaphragm 3. It contains located on the axis of the system convex corner. a virgin reflector 11, whose working faces are at an angle of 45 to the optical axis, and a concave angular virgin reflector 12. The planes of the reflector faces 11 are parallel to the corresponding planes of the reflector faces 12.

The kinematic diagram of the device is presented in FIG. Lens 2, diaphragm 3 with lens 4, lens 5 and lens 7 are mounted respectively on carriages 13, 14, 15 and 16, which can move along the optical axis due to kinematic connections, respectively 17, 18, 19 and 20. These links are identical

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structurally, they include an axis with a screw cut on it, along which the nut of the corresponding cage moves, and connected to constant gear ratios with a common kinematic link 21 by means of a kinematic pair, one of whose elements is fixed on the axis of the corresponding link, and the second is on the communications link 21. The lens 9 and the corner reflector 11 are rigidly fixed to the device body 22. The carriage 23 of the corner reflector 12 (FIG. 3) has the ability to move perpendicular to the optical axis of the device due to the kinematic link 24, which is connected to a constant gear ratio c. common kinematic connection 21. The difference of connection 24 from the described connections 17-20 is that the kinematic pair provides the movement of the carriage 23 perpendicular to the optical axis of the device, and not along it.

The optical system works as follows.

First, the optical circuit is tuned to radiation with the wavelength / io and the beam path in it is shown in FIG. The projection lens 2, through the system of corner reflectors 11 and 12, forms an image of source 1, enlarged a predetermined number of times, on the diaphragm 3, which cuts out a portion of the image of a given area. The raster 6 together with the lens 5 gives an image of this area in the plane of the second raster 8. Lens 9 displays the plane of the raster 8 on the input objective of the spectral instrument (not shown). This is described by the source image channel. It serves to illuminate the entrance slit 10 of the spectral instrument at a height. At the same time, the lens 4 creates an image of the projection lens 2 in the plane of the first raster 6. The lens 7, together with the raster 8, projects the image of the raster 6 into the plane of the entrance slit 10, This is the image transmission channel of the projecting lens. It serves as the illumination of the entrance slit 10 in width

When switching to measurements at a different wavelength H4, the alignment of the circuit is violated. This is due to the spectral dependence of the refractive index of the lens material. Since all

the lenses (except lens 9) are made of the same material, then the relative change in their focal lengths, and hence in the inter-lens gaps, is proportional to one magnitude D.

The mating (alignment) of the optical elements at the inter-lens gaps is carried out as follows. An angle of rotation proportional to D is applied to the input of the common kinematic link 21. Rotation from the axis of the common link 21 is transmitted by means of kinematic pairs of links 17-20 per pair of a screw-nut and a carriage connected to the corresponding nut, is moved along the optical axis before the optical element is set to the desired position. Lens 2 is moved relative to source 1, and lenses 4, 5, 7 are relative to lens 9.

. To compensate for the total change in the inter-lens gaps, simultaneously with the other moving optical elements, the perpendicular optical axis is displaced by the kinematic coupling 24. The corresponding planes of the corner reflectors 11 and 12 are parallel to each other. In this way, the adjustment of the optical system is restored.

A specific illumination system was used for a spectral instrument having the following parameters: focal length of the input lens F 600 mm, lens aperture ratio 1: 8, height of the entrance slit 12 mm.

The magnification of the projecting lens 1 was p-3 and remained constant for all wavelengths. Lenses 2, 5, 6, 7 and 8 are made of quartz, lens 9 is made of fluorite.

For all wavelengths in the operating frequency and spectrum, the conjugation of all the optical elements of the system, e. The optical circuit is constantly made, and this increases the stability of the output characteristics of the system and

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stability ossegtseni input spectral slit device.

Claims (3)

1. OPT 1ch system for illuminating the entrance slit of a spectral device containing a light source Projection lens, a diaphragm, a collective lens, a collector convex-flat lens with a first lens raster on a flat surface, a condenser flat-convex lens with a second lens raster on a flat surface and anti-vignetting lens, with the number of lenses in the first and the second raster is the same, characterized in that, in order to increase the stability of the light when working in different parts of the spectrum, a system of two lenses is installed between the projection lens and the diaphragm, or between the collective and collector lenses, or between the condenser and anti-viny lenses. corner reflectors with straight lines between the faces, the first of which is convex, is placed on the optical axis so that its faces are inclined relative to the optical axis at an angle of 45, the second, concave, is mounted so that it can move pendikul angles to the optical axis so that its faces are parallel to the faces of said first corner reflector, the projection lens, aperture, collectively, to the manifold of the condenser lens and become movable along the optical axis. 2. The system of claim 1, wherein the projection is collective and condenser. the lenses are made of quartz, and anti-vinetic is made of fluorite. 3. The system according to claim 2, characterized in that the projection 5 collective and condenser i lenses, the diaphragm and the second corner reflector are mounted in frames connected by a common kinematic connection with constant gear ratios. FIG. g yy