Passive thermal shaving structure of primary and secondary mirrors in telescope system

Abstract

This invention provides a passive thermal aberration structure for a telescope system's primary and secondary mirrors, comprising a load-bearing mechanism; a secondary mirror support assembled to the load-bearing mechanism; a compensation rod assembled to the secondary mirror support, wherein the installation direction of the compensation rod is parallel to the optical axis direction of the primary and secondary mirrors, and the compensation rod is made of a high-expansion material; and a secondary mirror focusing mechanism installed to the compensation rod, wherein the secondary mirror focusing mechanism is used to install the secondary mirror. The passive thermal aberration structure for the primary and secondary mirrors of this invention optimizes the structure, enabling the primary and secondary mirrors of the telescope system to maintain high optical precision even under temperature changes, while remaining simple, small in size, and occupying minimal space.

Description

Technical Field

[0001] This invention relates to the field of optoelectronic equipment technology, and more specifically, to a passive thermal differential correction structure for the primary and secondary mirrors of a telescope system. Background Technology

[0002] In modern large-aperture off-axis optical systems, the optical aperture is large, and the installation distance between the primary and secondary mirrors is generally on the order of meters. If carbon steel (with a linear expansion coefficient of 1×10-5) is used as the material, a temperature change of 5℃ will result in a change in the position of the primary and secondary mirrors of 1000×1×10-5×5, which is equal to 0.05 millimeters. This dimensional change will exceed the optical accuracy requirements and is unacceptable.

[0003] To meet the high-precision requirements for the spatial distance between the primary and secondary mirrors, the conventional approach is to install a six-bar adjustment mechanism on the secondary mirror, or to use Invar alloy, a material with near-zero expansion, as the material for the load-bearing components. However, the six-bar adjustment mechanism is complex to adjust and requires real-time correction using a calibration target when the temperature changes, making it difficult to meet customer requirements. At the same time, the load-bearing structure is large in size and complex in shape, and using Invar alloy is costly, has poor machinability, and has low stiffness and high density, resulting in relatively heavy products. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art.

[0005] Therefore, the present invention provides a passive thermal differential correction structure for the primary and secondary mirrors of a telescope system.

[0006] This invention provides a passive thermal differential correction structure for the primary and secondary mirrors of a telescope system, comprising:

[0007] Load-bearing mechanism;

[0008] The secondary mirror support is assembled into the load-bearing mechanism;

[0009] A compensation rod is assembled to the secondary mirror support, and the installation direction of the compensation rod is parallel to the optical axis direction of the primary and secondary mirrors. The compensation rod is made of a high-expansion material.

[0010] A secondary lens focusing mechanism is installed on the compensation rod, wherein the secondary lens focusing mechanism is used to install the secondary lens;

[0011] The spatial distance between the primary and secondary mirrors is L, the distance from the center of the fixing hole of the compensating rod away from the primary mirror to the center of the primary mirror is L2, the distance from the center of the fixing screw used to fix the end of the compensating rod to the center of the mounting hole of the secondary mirror is L1, the temperature change is Δt, the linear expansion coefficient of the compensating rod material is α1, and the expansion coefficient of the load-bearing mechanism or the secondary mirror support is α2. Then, each parameter meets the following requirements.

[0012] ΔL = ΔL2 - ΔL1 = 0;

[0013] Among them, ΔL1=L1·α1·Δt, ΔL2=L2·α2·Δt.

[0014] The passive thermal differential correction structure for the primary and secondary mirrors of the telescope system proposed in this invention includes a load-bearing mechanism, a secondary mirror support, a compensating rod, and a secondary mirror focusing mechanism. The load-bearing mechanism provides installation space for other structures or components. Specifically, the secondary mirror support is fixedly connected to the load-bearing mechanism, and a compensating rod made of a high-expansion material is mounted on the secondary mirror support. The secondary mirror focusing mechanism is mounted on the compensating rod. Therefore, when the external temperature changes, in order to satisfy ΔL = ΔL2 - ΔL1 = 0, and for the change in the spatial distance between the primary and secondary mirrors to approach zero, the values ​​of ΔL1 = L1·α1·Δt and ΔL2 = L2·α2·Δt need to be sufficiently close. Thus, when the compensating rod, which has a high coefficient of thermal expansion, is affected by temperature, its ΔL1 value changes significantly, while the load-bearing mechanism or secondary mirror support, which has a lower coefficient of thermal expansion, shows a smaller change in its ΔL2 value under this condition, thereby making the value of ΔL approach zero. In other words, this technical solution uses two materials with different coefficients of thermal expansion in its structural design to eliminate or reduce the influence of temperature on changes in the spatial distance between the primary and secondary mirrors. Compared to existing technologies, this invention optimizes the structure, making it simple, small in size, and requiring less space, while ensuring that the primary and secondary mirrors of the telescope system still meet the high optical precision requirements under temperature variations.

[0015] The passive thermal differential correction structure for the primary and secondary mirrors of the telescope system according to the above-described technical solution of the present invention may also have the following additional technical features:

[0016] In the above technical solution, the end of the compensation rod away from the main mirror is fixedly connected by a fixing screw, and the end closer to the main mirror is connected by a flexible hinge.

[0017] In this technical solution, since the compensating rod expands due to temperature changes, one end is fixedly connected by a bolt, while the other end, which will float during expansion, is connected using a flexible hinge to accommodate the expansion. Specifically, the flexible hinge connection can be a hinge or similar method, and is not specifically limited here.

[0018] The above technical solution also includes:

[0019] A guide component is disposed at the end of the compensating rod near the flexible hinge connection to guide the angle of the compensating rod during expansion.

[0020] This technical solution also includes a guide component to ensure that the angle and installation direction of the compensating rod do not change during thermal expansion. Specifically, the guide component can be a guide block structure with a guide groove formed on the compensating rod, and the guide block and guide groove forming a sliding connection. Of course, the above is only one specific structure of the guide component; any structure that can achieve the guiding function of the compensating rod falls within the protection scope of this technical solution, and no further limitations are imposed here.

[0021] In the above technical solution, one end of the secondary lens focusing mechanism is fixedly connected to the compensation rod, and the other end is connected by a flexible hinge.

[0022] In this technical solution, since the material expansion coefficient of the secondary lens focusing mechanism is low and the secondary lens focusing mechanism is mounted on the compensation rod, there is a large difference in thermal expansion between the two. In order to ensure that the secondary lens focusing mechanism is not deformed by tension, one end of the secondary lens focusing mechanism is fixedly connected to the compensation rod, and the other end is flexibly connected.

[0023] In the above technical solution, the load-bearing mechanism is composed of a load-bearing plate, and the secondary mirror support is assembled to the load-bearing plate.

[0024] In this technical solution, the load-bearing mechanism can be a load-bearing plate structure, which is made of carbon steel or titanium alloy to ensure a low coefficient of thermal expansion.

[0025] The above technical solution also includes:

[0026] The thermal insulation structure is assembled to the load-bearing plate.

[0027] This technical solution also includes a thermal insulation structure to ensure uniform temperature distribution within the load-bearing structure during temperature changes, thereby reducing structural bending deformation caused by temperature gradients.

[0028] In the above technical solution, the expansion coefficient of the load-bearing mechanism is the same as that of the secondary mirror support.

[0029] In this technical solution, the expansion coefficients of the load-bearing mechanism and the secondary mirror support are consistent to avoid the secondary mirror support from collapsing and falling off during the expansion process.

[0030] In the above technical solution, the primary mirror is assembled into the primary mirror chamber.

[0031] In this technical solution, the primary mirror is supported by the primary mirror chamber, ensuring the stability of the primary mirror installation.

[0032] Additional aspects and advantages of the invention will become apparent in the following description or may be learned by practice of the invention. Attached Figure Description

[0033] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0034] Figure 1 This is a cross-sectional view of the passive heat dissipation structure of the primary and secondary mirrors of the telescope system of the present invention;

[0035] Figure 2 This is a half-sectional view of the passive thermal differential structure of the primary and secondary mirrors of the telescope system of the present invention;

[0036] Figure 3 This is a structural diagram of the secondary mirror focusing mechanism, compensation rod, secondary mirror support, and guide parts in the passive thermal difference elimination structure of the primary and secondary mirrors of the telescope system of the present invention.

[0037] in, Figures 1 to 3 The correspondence between the reference numerals and component names in the attached drawings is as follows:

[0038] 1. Secondary mirror; 2. Secondary mirror focusing mechanism; 3. Primary mirror chamber; 4. Load-bearing mechanism; 5. Thermal insulation structure; 6. Compensation rod; 7. Secondary mirror support; 8. Guide components. Detailed Implementation

[0039] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0040] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0041] The following reference Figures 1 to 3 This describes the passive thermal differential structure of the primary and secondary mirrors of a telescope system provided according to some embodiments of the present invention.

[0042] Some embodiments of this application provide a passive thermal differential structure for the primary and secondary mirrors of a telescope system.

[0043] like Figures 1 to 3 As shown, the first embodiment of the present invention proposes a passive thermal differential correction structure for the primary and secondary mirrors of a telescope system, comprising:

[0044] 4. Load-bearing mechanism;

[0045] The secondary mirror support 7 is assembled to the load-bearing mechanism 4;

[0046] The compensation rod 6 is assembled to the secondary mirror support 7, and the installation direction of the compensation rod 6 is parallel to the optical axis direction of the primary and secondary mirrors 1. The compensation rod 6 is made of a high expansion material.

[0047] The secondary lens focusing mechanism 2 is installed on the compensation rod 6, wherein the secondary lens focusing mechanism 2 is used to install the secondary lens 1;

[0048] The spatial distance between the primary and secondary mirrors 1 is L, the distance from the center of the fixing hole of the compensating rod 6 away from the primary mirror to the center of the primary mirror is L2, the distance from the center of the fixing screw used to fix the end of the compensating rod 6 to the center of the mounting hole of the secondary mirror 1 is L1, the temperature change is Δt, the linear expansion coefficient of the material of the compensating rod 6 is α1, and the expansion coefficient of the load-bearing mechanism 4 or the secondary mirror support 7 is α2. Then, each parameter meets the following requirements.

[0049] ΔL = ΔL2 - ΔL1 = 0;

[0050] Among them, ΔL1=L1·α1·Δt, ΔL2=L2·α2·Δt.

[0051] The passive thermal differential correction structure for the primary and secondary mirrors 1 of the telescope system proposed in this invention includes a load-bearing mechanism 4, a secondary mirror support 7, a compensating rod 6, and a secondary mirror focusing mechanism 2. The load-bearing mechanism 4 provides installation space for other structures or components. Specifically, the secondary mirror support 7 is fixedly connected to the load-bearing mechanism 4. The compensating rod 6, made of a high-expansion material, is mounted on the secondary mirror support 7. The secondary mirror focusing mechanism 2 is mounted on the compensating rod 6. Therefore, when the external temperature changes, in order to satisfy ΔL = ΔL2 - ΔL1 = 0, and for the change in the spatial distance between the primary and secondary mirrors 1 to approach 0, the values ​​of ΔL1 = L1·α1·Δt and ΔL2 = L2·α2·Δt need to be sufficiently close. Thus, when the compensating rod 6, which has a high expansion coefficient, is affected by temperature, its ΔL1 value changes significantly, while the load-bearing mechanism 4 or the secondary mirror support 7, which has a lower expansion coefficient, shows a smaller change in its ΔL2 value under this condition, thereby making the ΔL value approach 0. In other words, this technical solution uses two materials with different coefficients of thermal expansion in its structural design to eliminate or reduce the influence of temperature on changes in the spatial distance between the primary and secondary mirrors 1. Compared to existing technologies, this invention optimizes the structure, making it simple, small in size, and space-saving, while ensuring that the primary and secondary mirrors 1 of the telescope system still meet the high optical precision requirements when the temperature changes.

[0052] The second embodiment of the present invention proposes a passive thermal difference reduction structure for the primary and secondary mirrors of a telescope system. Based on the first embodiment, the end of the compensation rod 6 away from the primary mirror is fixedly connected by a fixing screw, and the end closer to the primary mirror is connected by a flexible hinge.

[0053] In this embodiment, since the compensating rod 6 expands due to temperature, one end is fixedly connected by a fixing bolt, while the other end, which will float during expansion, is connected by a flexible hinge to meet the expansion requirements of the compensating rod 6. Specifically, the flexible hinge connection can be a hinge or other similar connection method, and is not specifically limited here.

[0054] The third embodiment of the present invention proposes a passive thermal differential correction structure for the primary and secondary mirrors of a telescope system, and further includes, based on any of the above embodiments:

[0055] A guide component 8 is disposed at the end of the compensating rod 6 near the flexible hinge connection to guide the angle of the compensating rod 6 during expansion.

[0056] In this embodiment, a guide component 8 is also included to ensure that the angle and installation direction of the compensation rod 6 do not change during thermal expansion. Specifically, the guide component 8 can be a guide block structure, with a guide groove formed on the compensation rod 6, and the guide block and the guide groove forming a sliding connection. Of course, the above is only one specific structure of the guide component 8, and any structure that can achieve the guiding function of the compensation rod 6 falls within the protection scope of this technical solution, and is not further limited here.

[0057] The fourth embodiment of the present invention proposes a passive thermal difference reduction structure for the primary and secondary mirrors of a telescope system. Based on any of the above embodiments, one end of the secondary mirror focusing mechanism 2 is fixedly connected to the compensation rod 6, and the other end is flexibly connected.

[0058] In this embodiment, since the secondary lens focusing mechanism 2 has a low coefficient of thermal expansion and is mounted on the compensation rod 6, there is a large difference in thermal expansion between the two. In order to ensure that the secondary lens focusing mechanism 2 is not deformed by tension, one end of the secondary lens focusing mechanism 2 is fixedly connected to the compensation rod 6, and the other end is flexibly connected.

[0059] The fifth embodiment of the present invention proposes a passive thermal differential structure for the primary and secondary mirrors of a telescope system. Based on any of the above embodiments, the load-bearing mechanism 4 is composed of a load-bearing plate, and the secondary mirror support 7 is assembled to the load-bearing plate.

[0060] In this embodiment, the load-bearing mechanism 4 can be a load-bearing plate structure, which is made of carbon steel or titanium alloy to ensure a low coefficient of thermal expansion.

[0061] The sixth embodiment of the present invention proposes a passive thermal differential correction structure for the primary and secondary mirrors of a telescope system, and further includes, based on any of the above embodiments:

[0062] The thermal insulation structure 5 is assembled to the load-bearing plate.

[0063] In this embodiment, a thermal insulation structure 5 is also included to ensure that the load-bearing mechanism 4 has a uniform temperature distribution when the temperature changes, thereby reducing the possibility of structural bending deformation caused by temperature gradients.

[0064] The seventh embodiment of the present invention proposes a passive thermal differential structure for the primary and secondary mirrors of a telescope system, and based on any of the above embodiments, the expansion coefficients of the load-bearing mechanism 4 and the secondary mirror support 7 are consistent.

[0065] In this embodiment, the expansion coefficients of the load-bearing mechanism 4 and the secondary mirror support 7 are kept consistent to prevent the secondary mirror support 7 from collapsing and falling off during the expansion process.

[0066] The eighth embodiment of the present invention proposes a passive thermal difference reduction structure for the primary and secondary mirrors of a telescope system, and based on any of the above embodiments, the primary mirror is assembled into the primary mirror chamber 3.

[0067] In this embodiment, the primary mirror is supported by the primary mirror chamber 3, ensuring the stability of the primary mirror installation.

[0068] In this specification, the illustrative expressions of the terms used do not necessarily refer to the same embodiments or examples. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0069] Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this invention shall be included within the scope of protection of this invention.

Claims

1. A passive athermalization structure of primary and secondary mirrors of a telescopic system, characterized in that, include: A load-bearing mechanism, wherein the load-bearing mechanism is composed of a load-bearing plate; Secondary mirror support, the secondary mirror support is assembled to the load-bearing plate, and the load-bearing mechanism has the same coefficient of thermal expansion as the secondary mirror support; A compensation rod is assembled to the secondary mirror support, and the installation direction of the compensation rod is parallel to the optical axis direction of the primary and secondary mirrors. The compensation rod is made of a high-expansion material. The end of the compensation rod away from the primary mirror is fixedly connected by a fixing screw, and the end closer to the primary mirror is connected by a flexible hinge. A guide component is provided at the end of the compensating rod near the flexible hinge connection to guide the angle of the compensating rod during expansion; A secondary lens focusing mechanism is installed on the compensation rod. The secondary lens focusing mechanism is used to install the secondary lens. One end of the secondary lens focusing mechanism is fixedly connected to the compensation rod, and the other end is flexibly connected. The thermal insulation structure is assembled to the load-bearing plate to ensure uniform temperature distribution of the load-bearing mechanism and reduce structural bending deformation caused by temperature gradient. The spatial distance between the primary and secondary mirrors is L, the distance from the center of the fixing hole of the compensating rod away from the primary mirror to the center of the primary mirror is L2, the distance from the center of the fixing screw used to fix the end of the compensating rod to the center of the mounting hole of the secondary mirror is L1, the temperature change is Δt, the linear expansion coefficient of the compensating rod material is α1, and the expansion coefficient of the load-bearing mechanism or the secondary mirror support is α2. Then, each parameter meets the following requirements. ΔL = ΔL2 - ΔL1 = 0; Where ΔL1 = L1•α1•Δt, ΔL2 = L2•α2•Δt.

2. The passive thermal differential correction structure for the primary and secondary mirrors of the telescope system according to claim 1, characterized in that, The primary mirror is assembled into the primary mirror chamber.

Images