JPH1114912A - Telescope device loaded into satellite - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a telescope device loaded into satellite in which distortion occurring on a primary mirror is reduced by constituting a screw part by cast iron. SOLUTION: The back surface of the primary mirror 21 is a flat surface, and the back surface of the primary mirror 21 is joined to a supporting constituting body 36 by plural jointed parts. A hole 41 is formed on the part of the back surface of the mirror 21, and the screw part 12 is stuck to the hole 41 by adhesive 40. A hole 43 for a screw is formed on a position corresponding to the screw part 42 stuck to the mirror 21 on the body 36. The hole 43 of the body 36 is stuck to the part 12 of the mirror 21 by a common screw 44, and the mirror 21 is fixed to the body 36. The part 12 is formed of the cast iron. Consequently, the difference of coefficient of thermal expansion between the fused quartz which is the constituting material of the mirror 21 and the cast iron which is the constituting material of the part 12 becomes smaller in comparison with the difference between the fused quarts and conventional stainless, so that the distortion occurring on the mirror 21 is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a telescope mounted on a satellite which is mounted on an observation satellite or the like and used for, for example, optical communication or image observation.

[0002]

2. Description of the Related Art A conventional telescope mounted on a satellite will be described with reference to FIGS.

In FIG. 3, a primary mirror 31 constituting a telescope is shown.
Has a concave surface with a large diameter and reflects light arriving from the outside (hereinafter abbreviated as incident light) in the direction of the sub-mirror 32 as shown by an arrow Y1. The secondary mirror 32 has a smaller diameter than the primary mirror 31 and reflects the light reflected by the primary mirror 31 in the direction of arrow Y2. That is, the light reflected by the sub-mirror 32 travels in the direction of the primary mirror 31, passes through the light transmission part 33 at the center of the primary mirror 31, and
For example, the light is sent to an optical system 34 arranged behind, for example, one light detection element 35. The light detection element 35 is constituted by a photodiode, a CCD element, or the like, and detects an optical signal coming from the outside.

The primary mirror 31 is screwed to a support structure 36 at a plurality of locations and is supported and fixed. The secondary mirror 32 is supported by a support structure 36 by a truss structure. For example, the sub-mirror 32 is supported by three wires 38 extending inward from an annular wire 37 surrounding the sub-mirror, and the space between the annular wire 37 and the support structure 36 is supported by a plurality of wires 39 arranged in parallel. ing.

Here, a structure for fixing the primary mirror 31 to the support structure 36 will be described with reference to FIG. FIG. 9 is a sectional view showing a part of each of the primary mirror 31 and the support structure 36. A hole 41 is formed in a part of the back surface of the main mirror 31, and a screw component 42 is fixed to the hole 41 with an adhesive. Further, a screw hole 43 is formed in the support structure 36 at a position corresponding to the screw component 42 fixed to the main mirror 31.

The screw holes 43 of the support structure 36 are provided.
And the screw part 42 of the primary mirror 31 are fixed with a common screw 44, and the primary mirror 31 is fixed to the support structure 36. Although FIG. 9 shows only one portion of the portion where the primary mirror 31 is fixed to the support structure 36 in FIG. 9, the fixing portion is provided at a plurality of portions.

By the way, in the above-described telescope device for mounting on a satellite, since the support structure 36 is made of stainless steel, the screw part 42 fixed to the back surface of the main mirror 31 is also made of stainless steel.

[0008]

In the above-mentioned conventional telescope for on-board satellite, the main mirror 31 is made of quartz, and the screw part 42 fixed to the back of the main mirror 31 is also made of stainless steel. I have. Therefore, when used in a place where the temperature change is large, such as in a space environment, the difference between the thermal expansion coefficients of the main mirror 31 and the screw part 42 causes the main mirror 31 to which the screw part 42 is fixed.
A portion may be distorted and the primary mirror 31 may be cracked.

Further, an adhesive is used for fixing the screw part 42. In this case, the adhesive shrinks during drying, and the primary mirror 31 at the bonded portion is distorted by tensile stress.
For this reason, the performance of the telescope is deteriorated or damaged.

An object of the present invention is to solve the above-mentioned conventional disadvantages, and an object of the present invention is to provide a satellite-mounted telescope apparatus in which distortion generated in a primary mirror is reduced.

[0011]

According to a first aspect of the present invention, there is provided a telescope for use on a satellite, which comprises: a primary mirror for reflecting incident light; and a primary mirror which is disposed opposite to the primary mirror and reflects the reflected light from the primary mirror. A satellite mount comprising: a secondary mirror that reflects in the mirror direction; a screw component fixed to a plurality of locations on the back surface of the primary mirror and having screw holes; and a support structure that supports and fixes the primary mirror using the screw component. In the telescope device for use, the screw part is made of cast iron.

Next, a second aspect of the present invention is a primary mirror that reflects incident light, a sub-mirror that is arranged to face the primary mirror and reflects light reflected by the primary mirror in the primary mirror direction, In a satellite-mounted telescope apparatus comprising: a screw component having a screw hole fixed to a plurality of positions on the back surface of the mirror; and a support structure for supporting and fixing the primary mirror using the screw component, the support structure has a peripheral annular shape. And a plurality of support portions projecting inwardly from the annular portion to intersect with the radius of the annular portion and having a screw hole formed at the tip thereof, and for a screw formed in the support portion. The main mirror is fixed to the support structure by fastening the hole and the screw hole of the screw component with a common screw.

A third aspect of the present invention is characterized in that, in the second aspect, the screw component is made of cast iron.

According to the configuration of the present invention described above, the screw parts fixed to a plurality of positions of the primary mirror are formed of cast iron. Therefore, the difference in the coefficient of thermal expansion between the quartz glass, which is a constituent material of the primary mirror, and the cast iron, which forms the screw part, is reduced, and the distortion generated in the primary mirror can be reduced.

Further, a supporting structure for supporting and fixing the primary mirror is provided with a plurality of peripheral annular portions and a plurality of screw holes formed in the distal end of the annular structural portion and projecting inwardly from the annular portion so as to intersect with the radius of the annular portion. The main mirror is fixed to the support structure by fastening a screw hole formed in the support portion and a screw hole of the screw component with a common screw. At this time, even if there is a difference in the thermal expansion rate between the primary mirror and the support structure, the stress generated due to the difference in the thermal expansion rate acts in the direction of rotating the entire primary mirror. For this reason, an excessive force does not act on the support portion of the primary mirror and the like, and distortion generated in the primary mirror is reduced. In this case, the difference in the coefficient of thermal expansion between the primary mirror and the support structure becomes less significant, and the degree of freedom in selecting the material of the support structure increases.

Further, the screw component is formed of cast iron, and the support structure projects from the peripheral annular portion and the radius of the annular portion inward from the annular portion, and a screw hole is formed at the tip thereof. By using a plurality of support portions, distortion generated in the primary mirror as described above can be reduced.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the first invention will be described below with reference to FIGS. In FIG. 1, the main mirror 21 constituting the telescope device mounted on a satellite has a concave surface having a large diameter, and the incident light is reflected by a sub-mirror 32 as shown by an arrow Y1.
Reflect in the direction. The secondary mirror 32 has a smaller diameter than the primary mirror 21, and reflects the light reflected by the primary mirror 21 in the direction of arrow Y2. The light reflected by the sub-mirror 32 travels in the direction of the main mirror 21, passes through the light transmission part 33 at the center of the main mirror 21, to the optical system 34 disposed, for example, behind the main mirror 21, and then to the photodetector 35. Sent. The light detecting element 35 is constituted by a photodiode, a CCD element, or the like, and detects an optical signal coming from the outside.

The primary mirror 21 is provided with a support structure 3 to be described later.
6 are supported and fixed at a plurality of positions by an example of screwing. The secondary mirror 32 is supported by a support structure 36 by a truss structure. For example, the secondary mirror 32 has three wires 38 extending inward from an annular wire 37 surrounding it.
The annular wire 37 and the support structure 36 are supported by a plurality of wires 39 arranged in parallel.

Here, a structure for fixing the primary mirror 21 to the support structure 36 will be described with reference to FIG. Primary mirror 2
1 has a flat surface, and the back surface of the main mirror 21 and the support structure 36 are joined at a plurality of joints. FIG. 2 is a cross-sectional view of a part of these joints. A hole 41 is formed in a part of the back surface of the main mirror 21, and a screw component 42 is fixed to the hole 41 with an adhesive 40. In addition, a screw hole 43 is formed in the support structure 36 at a position corresponding to the screw component 42 fixed to the main mirror 21.

Then, the screw holes 43 of the support structure 36 are formed.
And the screw part 42 of the main mirror 21 are fixed with a common screw 44, and the main mirror 21 is fixed to the support structure 36. Note that FIG. 9 described above shows only one portion of the portion where the main mirror 21 is fixed to the support structure 36, which has been described above. However, the fixing portion is provided at a plurality of portions. And
The screw part 42 is formed of cast iron.

By using the screw component 42 having the above-described configuration, the primary mirror 21 to which these components are fixed has a difference in thermal expansion coefficient between quartz glass, which is a component thereof, and cast iron, which is a component of the screw component. It is smaller than the difference from the conventional stainless steel, and the distortion generated in the primary mirror is reduced.

Next, an embodiment of the second invention will be described with reference to FIGS. In FIG. 3, the main mirror 11 constituting the telescope has a concave surface having a large diameter, and reflects incident light in the direction of the sub-mirror 32 as indicated by an arrow Y1. The secondary mirror 32 has a smaller diameter than the primary mirror 11, and reflects the light reflected by the primary mirror 11 in the direction of arrow Y2. The light reflected by the sub-mirror 32 travels in the direction of the main mirror 11, passes through the light transmission part 33 at the center of the main mirror 11, to the optical system 34 disposed behind the main mirror 11, for example, and then to the light detection element 35. Sent. The light detecting element 35 is constituted by a photodiode, a CCD element, or the like, and detects an optical signal coming from the outside.

The primary mirror 11 is provided with a support structure 3 to be described later.
6 are supported and fixed at a plurality of positions by an example of screwing. The secondary mirror 32 is supported by a support structure 36 by a truss structure. For example, the secondary mirror 32 has three wires 38 extending inward from an annular wire 37 surrounding it.
The annular wire 37 and the support structure 36 are supported by a plurality of wires 39 arranged in parallel.

Here, the structure for fixing the main mirror 11 to the support structure 36 will be described with reference to FIG. 4 showing a front view of the joint surface between the main mirror and the support structure, and FIG.

FIG. 4A shows a back surface of the primary mirror 11, and a dashed line d1 indicating a radius of 120 degrees (O is the center) on this surface.
Three holes 211 to 213 are formed on to d3.
Then, screw parts 22 such as stainless steel nuts are provided in the holes.
1 to 223 are fixed with an adhesive.

Further, the support structure 16 shown in FIG.
3 are provided inwardly so as to intersect with the radius of the annular portion, and the support portions 241 to 243 are provided with the screw holes 251 so as to correspond to the screw components 221 to 223 on the back surface of the main mirror 11. 253 are formed. The support portions 241 to 243 in the illustrated example are perpendicular to the dashed lines D1 to D3 of the radius including the screw holes 251 to 253, and the effect of the present invention that the distortion generated in the primary mirror can be reduced is remarkable. This is an example that can occur.

Then, as shown in FIG.
1 to 243 screw holes 251 to 253 and the screw component 2
The screw holes 21 to 223 are fastened and fixed with a common screw 44.

As described above, even if there is a difference in the thermal expansion rate between the primary mirror and the supporting structure, the stress generated by the difference in the thermal expansion rate acts in the direction of rotating the entire primary mirror. For this reason, an excessive force does not act on the support portion of the primary mirror and the like, and distortion generated in the primary mirror is reduced. Thereby, the difference in the coefficient of thermal expansion between the primary mirror and the support structure becomes less significant, and the degree of freedom in selecting the material of the support structure is increased.

Next, an embodiment of the third invention will be described with reference to FIGS. In FIG. 6, the main mirror 11 constituting the telescope has a concave surface having a large diameter, and reflects incident light in the direction of the sub mirror 32 as indicated by an arrow Y1. The secondary mirror 32 has a smaller diameter than the primary mirror 11, and reflects the light reflected by the primary mirror 11 in the direction of arrow Y2. The light reflected by the sub-mirror 32 travels in the direction of the main mirror 11, passes through the light transmission part 33 at the center of the main mirror 11, to the optical system 34 arranged behind the main mirror 11, for example, and then to the photodetector 35. Sent. The light detecting element 35 is constituted by a photodiode, a CCD element, or the like, and detects an optical signal coming from the outside.

The primary mirror 11 is provided with a support structure 3 to be described later.
6 are supported and fixed at a plurality of positions by an example of screwing. The secondary mirror 32 is supported by a support structure 36 by a truss structure. For example, the secondary mirror 32 has three wires 38 extending inward from an annular wire 37 surrounding it.
The annular wire 37 and the support structure 36 are supported by a plurality of wires 39 arranged in parallel.

7 (a) and 7 (b) show a front view of a joint surface between the main mirror and the support structure, and FIG. 7 (c) shows a part of the structure for fixing the main mirror 11 to the support structure 36. Are shown and described.

FIG. 7A shows a back surface of the primary mirror 11, and a dashed line d1 showing a radius of 120 degrees (O is the center) on this surface.
Three holes 211 to 213 are formed on to d3.
Then, screw parts 221 to 2 such as cast iron nuts are provided in the holes.
23 is fixed with an adhesive.

Further, the support structure 16 shown in FIG.
3 are provided inwardly so as to intersect with the radius of the annular portion, and the support portions 241 to 243 are provided with the screw holes 251 so as to correspond to the screw components 221 to 223 on the back surface of the main mirror 11. 253 are formed. The support portions 241 to 243 in the illustrated example are perpendicular to the dashed lines D1 to D3 of the radius including the screw holes 251 to 253, and the effect of the present invention that the distortion generated in the primary mirror can be reduced is remarkable. This is an example that can occur.

Then, as shown in FIG.
1 to 243 screw holes 251 to 253 and the screw component 2
The screw holes 21 to 223 are fastened and fixed with a common screw 44.

According to the above description, the present invention firstly supports the support structure 16.
With the above configuration, even if there is a difference in the thermal expansion rate between the primary mirror 11 and the support structure, the stress generated due to the difference in the thermal expansion rate acts in the direction of rotating the entire primary mirror. For this reason, an excessive force does not act on the support portion of the primary mirror and the like, and distortion generated in the primary mirror is reduced. This makes the difference in the coefficient of thermal expansion between the primary mirror and the support structure less significant and has the significant advantage of increasing the degree of freedom in selecting the material of the support structure. Further, the present invention uses the screw component 12 having the above-described configuration in addition to the improved structure of the support structure 16, so that the primary mirror to which these components are fixed can be configured with respect to the quartz glass which is the component material. The difference in the coefficient of thermal expansion with cast iron is smaller than that of conventional stainless steel,
The distortion generated in the primary mirror can be reduced.

[0036]

The satellite telescope apparatus according to the present invention includes any one of the above three elements, and has a remarkable advantage that distortion generated in the primary mirror is reduced.

That is, the first of the three elements of the present invention is:
The second is that the difference in the coefficient of thermal expansion is reduced by changing the constituent material of the screw component attached to the main mirror made of quartz glass to cast iron to reduce the difference in the coefficient of thermal expansion. A plurality of support portions projecting inward from the annular portion to intersect with the radius of the annular portion and having a screw hole formed at the tip thereof, and a screw hole formed in the support portion. With the configuration of the support structure in which the screw hole of the screw component is fastened with a common screw, the stress generated by the difference in the thermal expansion coefficient between the primary mirror and the support structure is converted into a direction in which the entire primary mirror is rotated, and the primary mirror is rotated. Is to reduce the distortion that occurs in
Thirdly, it is a combination of the first and second elements.

[Brief description of the drawings]

FIG. 1 is a perspective view for explaining a satellite mounted telescope device according to one embodiment of the first invention.

FIG. 2 is a cross-sectional view for explaining a part of the onboard satellite telescope device according to the embodiment of the first invention.

FIG. 3 is a perspective view for explaining a satellite mounted telescope device according to one embodiment of the second invention;

FIGS. 4 (a) and (b) are both figures according to the second invention.
FIG. 2 is a front view for explaining a part of the onboard satellite telescope device of the embodiment.

FIG. 5 is a cross-sectional view for explaining a part of a telescope device mounted on a satellite according to one embodiment of the second invention.

FIG. 6 is a perspective view for explaining a satellite-mounted telescope device according to one embodiment of the third invention.

FIGS. 7 (a) to 7 (c) are all drawings according to the third invention.
(A) and (b) are front views and (c) is a cross-sectional view for explaining a part of the telescope device mounted on a satellite according to the embodiment.

FIG. 8 is a perspective view for explaining a conventional telescope device mounted on a satellite.

FIG. 9 is a cross-sectional view illustrating a part of a conventional telescope mounted on a satellite.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Primary mirror 12 ... Screw part 16 ... Support structure 33 ... Light transmission part 34 ... Optical system 35 ... Light detection element 37 ... Annular wire 38, 39 ... Wire 40 ... Adhesive material 41 ... Hole 43 ... Screw hole 44 ... Screws 211 to 213 ... holes 221 to 223 ... screw parts 241 to 243 ... support parts 251 to 253 ... screw holes d1 to d3, D1 to D3 ... radius O ... center Y1, Y2 ... light reflection direction

Claims (3)

[Claims] 1. A primary mirror for reflecting incident light, a sub-mirror arranged opposite to the primary mirror to reflect reflected light of the primary mirror in the direction of the primary mirror, and fixed to a plurality of locations on the back surface of the primary mirror. And a supporting structure for supporting and fixing the primary mirror using the screw component, a satellite mounted telescope apparatus, wherein the screw component is made of cast iron. Telescope for satellites. 2. A primary mirror for reflecting incident light, a sub-mirror disposed opposite to the primary mirror and reflecting the reflected light of the primary mirror in the primary mirror direction, and fixed to a plurality of locations on the back surface of the primary mirror. A telescopic device mounted on a satellite, comprising: a screw component having a screw hole and a support structure that supports and fixes the primary mirror using the screw component. It is composed of a plurality of support parts projecting inwardly intersecting with the radius of this annular part and having a screw hole formed at the tip thereof,
And a screw hole formed in the support portion and a screw hole of the screw component are fixed with a common screw, and the primary mirror is fixed to the support structure. 3. The satellite mounted telescope apparatus according to claim 2, wherein the screw part is made of cast iron.