JP2706006B2 - Astronomical telescope - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reflection type astronomical telescope having a third mirror.

[0002]

2. Description of the Related Art FIG. 5 is a conceptual diagram for explaining a schematic configuration of a celestial astronomical telescope. In the figure, reference numeral 11 denotes a main mirror unit structure provided with a primary mirror and the like, 12 denotes a barrel top structure provided with a primary focus correction system and a secondary mirror, and 13 denotes a barrel constituting a barrel holding the primary mirror and the secondary mirror. Part structure, 14 is a gantry structure that constitutes the gantry, and 15 is a Nasmith table for installing observation equipment.

FIG. 6 is an explanatory view schematically showing an optical system in an astronomical telescope. In the figure, reference numeral 1 denotes a primary mirror that reflects light from a celestial body; 51, a primary focus at which an image is formed by light reflected by the primary mirror 1; and 2, a primary focus provided before the primary focus 51 (primary mirror side). A secondary mirror 52 is a Cassegrain focal point where an image is formed by the light reflected by the secondary mirror 2, a third mirror 3 reflects light traveling from the secondary mirror 2 to the Cassegrain focal point 51, and 53 is reflected by the third mirror 3. This is a Nasmith focus where an image is formed by the light.

[0004] Reference numerals 4a to 4g denote mirrors or lenses constituting a Kuude relay system for guiding light toward the Nasmith Smith focus 53 to a Coude focus 54.

Next, astronomical observation using an astronomical telescope will be described. An imaging device and a spectroscope are installed at the main focal point 51, the Cassegrain focal point 52, the Nasmith focal point 53, and the Kuude focal point 54, respectively. At the time of observation, the astronomical telescope tracks the diurnal motion of the celestial body by driving the two axes of the altitude axis and the azimuth axis. An astrophotograph is created by an imaging device, and a spectrum is analyzed by a spectroscope.

At the time of observation at the Cassegrain focal point 52, the third mirror 3 on the optical path from the secondary mirror 3 to the Cassegrain focal point 52 is removed. Further, the third mirror 3 is attached for observation at the Nasmith Smith focus 53 or the Coude focus 54. Then, when performing observation at the Nasmith Smith focal point 53, the mirror 4a is removed, and an observation device placed on the Nasmith Smith table 15 is used. In addition,
Although only one Nasmith focus 53 is shown in FIG. 6, another Nasmith focus may be set on the opposite side (to the right of the third mirror 3 in FIG. 6). Another one
At the time of observation at the two Nasmith focal points, the third mirror 3
Light is reflected in a direction opposite to the direction shown in FIG.

[0007]

Since the astronomical telescope having the third mirror is constructed as described above, when switching from the observation at the Nasmith focus 53 or the Coude focus 54 to the observation at the Cassegrain focus 52, the third mirror is used. 3 needs to be removed, but in a conventional astronomical telescope, the third
The mirror 3 was manually attached and detached. In the case where the main mirror 1 has a large diameter, the diameter of the third mirror 3 also becomes large, and there is a problem that the work efficiency is reduced in a manual attaching / detaching operation, which leads to a reduction in the efficiency of the observation operation.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and has as its object to provide an astronomical telescope that can easily set a third mirror to a set position and remove the third mirror from the set position.

[0009]

The astronomical telescope according to the present invention is installed outside the optical path of the light reflected by the sub-mirror, and one end of the third mirror housed outside the optical path is connected to a light-shielding tube. A linear actuator to be moved in the cylinder length direction, and a linear mirror installed outside the optical path of the reflected light in a direction orthogonal to the cylinder length direction of the light shielding cylinder and orthogonal to the drive direction of the linear actuator. And a rail for guiding the end.

The astronomical telescope according to the second aspect of the present invention is provided with a first third mirror which is arranged outside the optical path of the reflected light and which is installed when guiding the reflector to the first Nasmyth focus. A first guide rail having a portion forming the same angle as the angle and a portion parallel to the storage portion of the first third mirror;
A first direct-acting cylinder for generating a driving force for moving the third mirror along the first guide rail; and a first linear cylinder disposed outside the optical path of the reflected light, for guiding the reflecting mirror to the second Nasmith Smith focus. A second guide rail having a portion at the same angle as the installation angle of the second third mirror to be installed and a portion parallel to the storage portion of the second third mirror, and a second third mirror And a second direct-acting cylinder that generates a driving force for moving the cylinder along the second guide rail.

[0011]

According to the first aspect of the invention, the linear actuator and the rail cooperate to move the third mirror between the storage location outside the optical path and the installation location for observation.

[0012] The first guide rail and the first linear motion cylinder in the invention described in claim 2 cooperate to form the first guide rail.
Is moved between the storage location outside the optical path and the installation location for observation, and the second guide rail and the second linear motion cylinder cooperate to form the second third mirror. The mirror is moved between a storage place outside the optical path and a setting place set for observation.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing the periphery of a third mirror of an astronomical telescope according to one embodiment of the present invention. In the figure, 3a, 3
b is a third mirror (3a shows the one at the time of storage, 3b shows the one at the time of unfolding. That is, it is actually one. Similarly, a symbol a is the one at the time of storage. , And the symbol “b” indicates a state at the time of expansion.
As shown in FIG. ), 21a,
21b is a mirror cell that supports the third mirrors 3a and 3b.

Reference numeral 22 denotes a linear actuator (hereinafter, referred to as a linear motor) such as a linear motor that moves in the axial direction of a light shielding tube 41 provided in the lens barrel. Reference numerals 23a and 23b fix the mirror cells 21a and 21b to the linear motor 22. Pins 24 are rails laid on a plane perpendicular to the axis of the light-shielding cylinder 41 in a direction perpendicular to the direction of movement of the linear motor 22, and 25a and 25b are connection members 27a and 27b fixed to the mirror cells 21a and 21b. To the moving bodies 28a, 2
8b, 28a and 28b are rails 2
Reference numeral 29 denotes a moving body that moves on the upper surface of the moving member 4.

Reference numeral 42 denotes a bearing for rotating the light shielding cylinder 41 by 180 °. The light-shielding cylinder 41 is rotated 180 ° via a bearing 42 by driving a motor (not shown), whereby the third mirrors 3a and 3b are rotated 180 °.
Rotated. Reference numeral 43 denotes a window provided in the light-shielding cylinder 41 for guiding the light reflected by the third mirror 3b to the Nasmith focus, and 44 denotes a gantry. Reference numeral 61 denotes light reflected by the secondary mirror.

Next, the operation will be described. First, it is assumed that the third mirror 3 is at the position indicated by the solid line in FIG. 1 (that is, the position of the third mirror 3a). In this case, the light reflected by the secondary mirror directly reaches the Cassegrain focus.

In this state, when observation is performed at the Nasmith focus or the Coude focus, the third mirror 3 is controlled by the control device (not shown) to move the third mirror 3 to the position indicated by the chain line in FIG. (The position of the mirror 3b).

More specifically, the linear motor 22 generates a driving force in the C → N direction shown in FIG. 1 according to a command from the control device, and one end of the mirror cell 21, that is, one end of the third mirror 3 is pushed down. Further, since the mirror cell 21 is also fixed to the moving body 28 moving on the rail 24, the other end of the mirror cell 21, that is, the other end of the third mirror 3 is connected to the linear motor 2
2 in a direction orthogonal to the driving direction.

When the moving body 28 reaches a predetermined position (the position of the moving body 28b in FIG. 1), the driving of the linear motor 23 is stopped. At this time, the moving body 28 is
(Position of the moving body 28b in FIG. 1)
, And is bonded and held to a stopper 29 made of, for example, a magnetic material.

As a result, the third mirror is at a position where the light reflected by the sub-mirror is blocked (the position of the third mirror 3b in FIG. 1, usually at an angle of 45 ° with respect to the light incident direction). It will be set. In this state, the light reflected by the secondary mirror passes through the window 43 and reaches the Nasmyth focus.

In this state, in order to house the third mirror 3, the linear motor 22 is energized and the pin 23 is
What is necessary is just to pull up from the position of the pin 23b to the position of the pin 23a.

FIG. 2 is a front sectional view showing the periphery of a third mirror of an astronomical telescope according to a second embodiment of the present invention. Also,
3 is a top view and FIG. 4 is a side view. In each of the drawings, reference numeral 31 denotes a third mirror (hereinafter, third mirror 3 depending on the position).
1a or the third mirror 31b. ), 32
Is a mirror cell of the third mirror 31, and 33 is a guide rail along which the mirror cell 32 moves. The guide rail 33 has a bent portion forming an angle of 45 °.

Numeral 34 denotes a linear motion cylinder for pushing up the mirror cell 32, and numeral 35 denotes a guide roller which moves along the guide rail 33. Also, 36 is the other third mirror provided opposite one third mirror 31, 37 is the mirror cell of the third mirror, 38 is the other guide rail, 39 is the other linear motion cylinder, and 40 is the other It is a guide roller. Also, 61 indicates reflected light from the secondary mirror, and 44 indicates a gantry.

Next, the operation will be described. First, the two third mirrors 31 and 36 are in the storage position (the third mirror 31 in FIG. 2).
a, 36a). In this state, the light reflected by the secondary mirror directly reaches the Cassegrain focus. Here, when performing observation at the first Nasmyth focus, the control device (not shown) drives the linear motion cylinder 34.

That is, the mirror cell 32 and the third mirror 31 are moved by the drive of the linear motion
Descend along 3 Then, when the third mirror 31b is installed at the installation position, the linear motion cylinder 34 stops. In this state, the light reflected by the secondary mirror is reflected by the third mirror 31b and reaches the first Nasmyth focus.

When performing observation at the second Nasmis focus or Cassegrain focus, the direct acting cylinder 34 receives a drive command in the reverse direction. That is, the mirror cell 32 and the third mirror 31b are pulled up along the guide rail 33 and are stored at the storage position. Then, when performing observation at the second Nasmith Smith focus, the third mirror 36 is moved from the storage position to the installation position (the position of the third mirror 36b in FIG. 2) by the linear motion cylinder 39.

By providing the guide rails 33 and 38 having the 45 ° bent portions as described above, the third mirrors 31 and 3 are provided.
Strict precision is not required when installing 6 at the installation position. Therefore, the stop accuracy of the linear motion cylinders 34 and 39 may be coarse. In addition, the angle of the bend is set to 45 according to the observation requirements.
The angle may be other than °.

Further, when two Nasmith focuses are used as dedicated observation places, respectively, such that the first Nasmith focus is used for optical observation and the second Nasmith focus is used for infrared observation. According to the embodiment, there is no need to replace the reflection film set on the third mirror or replace the third mirror.

Since the heat generated by the optical telescope deteriorates the seeing, in each of the above-described embodiments, a heat pipe is provided near the linear motor 22 and the linear motion cylinders 34 and 39, which are heat generating elements, to cool them. You may.

[0030]

As described above, according to the first aspect of the present invention, the linear actuator for moving one end of the third mirror in the lengthwise direction of the light-shielding tube and the light-shielding tube for the other end of the third mirror are provided. The third mirror is removed when switching the observation position from the Cassegrain focal point to the Nasmith focal point or the Coude focal point or vice versa. It is possible to change the direction of the optical path without any change, and obtain an effect of improving the efficiency of the observation operation.

According to the second aspect of the present invention, the astronomical telescope is provided with a guide rail for guiding the first third mirror to a place for installing and storing the first third mirror, and a first third mirror. A first linear motion cylinder for moving the mirror along the first guide rail, and a second linear movement cylinder for installing and storing the second third mirror.
A second guide rail for guiding the third mirror of the second
Since the second linear motion cylinder for moving the mirror along the second guide rail is provided, when the observation position is switched to the Cassegrain focus, the first Nasmith Smith focus or the second Nasmith Smith focus, There is no need to replace the third mirror or replace the reflecting film installed on the third mirror, and the accuracy may be rough when setting the third mirror at the installation position.
There is an effect that a product that does not require precise parts can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing the periphery of a third mirror of an astronomical telescope according to an embodiment of the present invention.

FIG. 2 shows a third example of an astronomical telescope according to another embodiment of the present invention;
It is front sectional drawing which shows the periphery of a mirror.

FIG. 3 is a sectional view showing a section taken along a line III-III of FIG.

FIG. 4 is a sectional view showing a section taken along line IV-IV of FIG.

FIG. 5 is a conceptual diagram for explaining a schematic configuration of an astronomical telescope.

FIG. 6 is an explanatory view schematically showing an optical system of the astronomical telescope.

[Explanation of symbols]

 3a, 3b Third mirror 22 Linear motor (linear actuator) 24 Rail 31a, 31b Third mirror (first third mirror) 33 Guide rail (first guide rail) 34 Linear cylinder (first linear cylinder) ) 36a, 36b Third mirror (second third mirror) 38 Guide rail (second guide rail) 39 Linear cylinder (second linear cylinder)

Claims (2)

(57) [Claims] 1. An astronomical telescope having a third mirror for guiding reflected light, which is light reflected by a primary mirror and then reflected by a secondary mirror, to a Nasmith focus, is installed outside the optical path of the reflected light,
A linear actuator for moving one end of the third mirror housed outside the optical path in a tube length direction of a light-shielding tube supporting the third mirror; A astronomical telescope, comprising: a rail installed outside an optical path of the reflected light in a direction orthogonal to a driving direction of an actuator, and a rail for guiding the other end of the third mirror. 2. An astronomical telescope having a third mirror for guiding reflected light, which is light reflected by a primary mirror and then reflected by a secondary mirror, to a Nasmith focus, wherein the third mirror is a first Nasmith focus corresponding to the first Nasmith focus. A third mirror and a second third mirror corresponding to the second Nasmyth focus, and are disposed outside the optical path of the reflected light;
A portion forming the same angle as the installation angle of the first third mirror installed when guiding the reflected light to the first Nasmith Smith focus and a portion parallel to the housing portion of the first third mirror are provided. A first guide rail having a first guide rail, and a first guide rail for generating a driving force for moving the first third mirror along the first guide rail.
A linear motion cylinder, and disposed outside the optical path of the reflected light,
A part having the same angle as the installation angle of the second third mirror and a part parallel to the storage part of the second third mirror, which are installed when guiding the reflected light to the second Nasmith Smith focus, A second guide rail having a second driving force for moving the second third mirror along the second guide rail.
An astronomical telescope comprising a linear motion cylinder.