SU754243A1 - Device for measuring telescope-reflector tube bending - Google Patents

Description

The invention relates to instrument making and can be used to measure the bending of telescopic reflector tubes.

Known measurement devices' 5

the bends of the telescope-reflector tube have an alignment mark / installed in the focal plane of the tube, a beam splitter installed between the main and secondary mirrors of the tube, a flat-10 parallel plate bonded to the secondary mirror of the tube, an analyzer of the alignment image of the alignment mark installed in the focal plane of the tube [1 ]. 15

However, the placement of the beam splitter and the plane-parallel plate in the course of all rays during the operation of the telescope when observing astronomical objects leads to large energy losses.

It is also known a device in which, instead of a beam splitter and a plane-parallel plate, a long-focus lens was inserted (25 mm, 2000 mm, 4000 mm), mounted on the outer tube body, using an objective tube so that the optical axes of the lens lens and pipes

2

were parallel, and a system of reflectors for the optical connection of the device with the Tube under control. The displacement analyzer is installed in the focal plane of the lens objective and is attached to the objective tube [2].

However, the device has insufficient accuracy in measuring pipe bending due to the fact that the device measures differential bending (the difference in bending of the pipe being monitored and the long-focus telescopic system consisting of an objective tube, to one of the landing flanges of which is attached a long-focal lens lens) .

The aim of the invention is to improve the accuracy of measurements of the bending of the tube of the telescope-reflector.

This goal is achieved by the fact that, in the tube bending measurement device, an alignment mark is placed in the rear focal plane of the lens objective optically conjugated by the beam splitter with the analyzer plane, the central non-working part of the secondary mirror of the telescope is equipped with an additional coaxial with it

3

754243

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a mirror forming an afocal system together with its main mirror, and a system of reflectors made in the form of two pentaprisms, the entrance face of the first of which overlaps half the light diameter of the lens objective, and the exit face is parallel to the entrance opposite face of the second pentaprism, placed in front of the additional mirror, and the angle between the axes of the lens objective and the telescope, equal to the angle between the normal to the output face of the second pentaprism and the optical axis of the additional mirror, is .0 / 48, where ϋ is the light second auxiliary mirror diameter, d -'rasstoyanie along the optical axis between the main and auxiliary mirrors.

The drawing shows a diagram of a device for measuring pipe bending.

Device consisting of the main '

1 and an additional 2 mirrors, contains, a short-focus (7 = 100, ..., 200 mm) lens lens 3, mounted on one of the stretch marks connecting the secondary mirror to the pipe body (in Fig. 1 the extensions and the body are not shown), the beam splitter 4 and, installed in the focal plane of the lens 3, alignment mark 5 and the displacement analyzer b, an additional mirror 7 placed in the non-working part of the (central) secondary mirror 2 and forming an afocal system together with the main mirror 1, and a system of reflectors made in the form two petapryzm, the entrance face the first of which 8 overlaps half of the light diameter of the lens objective 3, and the output face is parallel to the input opposite face of the second pentaprism 9 placed in front of the additional mirror 7.

The optical axis of the lens object va 3 is located at an angle β = ₇ / 4εί (0 ₇ is the light diameter of the mirror 7,

8 - - the distance on the optical axis between the mirrors 1 and 7) to the optical axis of the telescope.

The radius of curvature of the mirror 7 is 25 ^ (5 ₂ ~ distance from the secondary zerkgsha 2 to the focus of the main mirror 1), mirrors 2 and 7 are coaxial.

The device works as follows.

The luminous flux of the mark 5, after being reflected by the light holder 4, passes the lens objective 3. Half of the beam of parallel rays emerging from the lens 3 passes through the peptprisms 8 and 9, reflects from mirrors 7 and 1, passes the lens objective 3., in the focal plane of which on the optical axis analyzer; b offset; an image of an alignment mark is built.

The second half of the parallel beam that emerged from the lens objective is reflected from the mirrors.

1 and 7, passes the pentaprism 8 and 9, and a lens objective 3, in the focal plane of which a second image of the alignment mark is built on the optical axis of the bias analyzer 5.

The appearance of pipe bending leads to tilting the mirror 2 by an angle <y ₂ (rad), a mirror 1 by an angle _{ί £} {rad) and de-centering them d £ (mm).

Since mirror 7 is coaxial with the mirror

2 and rigidly fastened to it, then it leans on the angle οί ₇ = and focuses on D? . When bent, both images of the alignment mark diverge in the direction perpendicular to the optical axis of the lens 3 by the value E, determined from the ratio

2 = 4 (οί, + οί ₇ + 2 ^ 7 ”)

Analyzer b offset measures _; , E - the mutual displacement of two images of the alignment mark caused by the bending of the pipe.

The accuracy of measuring the bending of the pipe is further increased by the fact that the inclinations and displacements of the assembly consisting of the lens objective 3, the beam splitter 4, the alignment mark 5 and the displacement analyzer b, as well as the random displacement of the lens objective 3 in this assembly do not affect the accuracy of the measurement of the bow bending.

Claims (1)

Claim 1. A device for measuring the bending of a reflecting telescope tube, whose optical system consists of a primary and secondary mirrors, containing an alignment mark, a lens lens, an alignment mark image displacement analyzer installed in the focal plane of the lens objective, a system of reflectors for optical communication of the device with a controlled telescope , characterized in that, in order to improve accuracy, the alignment mark is placed in the rear focal plane of the lens objective optically conjugated by a beam splitter with The analyzer’s intensity, the central non-working part of the secondary mirror of the telescope is equipped with an additional mirror coaxial with it, forming together with its main mirror an afocal system, and the system of reflectors is made in the form of two pentarals, the first face of which covers half the light diameter of the lens objective, and the output face parallel to the entrance face which is opposite to it the second pentalriz5 754243 ό we, placed in front of the additional mirror, the angle between the optical axes of the lens objective and the telescope, equal to the angle between the normal to the output face of the second pentaprism and the optical axis of the additional mirror, is 0/46, where 0 is the light diameter of the additional mirror, (5 is the optical distance axes between the main and additional mirrors.