WO2019235566A1

WO2019235566A1 - Fixture, optical device, and method for manufacturing optical device

Info

Publication number: WO2019235566A1
Application number: PCT/JP2019/022527
Authority: WO
Inventors: 直人飯田; 威男馬目
Original assignee: 京セラ株式会社
Priority date: 2018-06-08
Filing date: 2019-06-06
Publication date: 2019-12-12
Also published as: JPWO2019235566A1

Abstract

A fixture for fixing an optical component to a fixing table is provided with: a holding component to which the optical component is fixed; a first member to which the holding component is fixed; a third member which is fixed to the fixing table; a second member which connects and fixes the first member and the third member and bolts for fastening the holding component to the first member, the first member to the second member, and the second member to the third member, respectively. A first virtual plane across which the holding component and the first member face each other, a second virtual plane across which the first member and the second member face each other, and a third virtual plane across which the second member and the third member face each other do not lie in the same plane.

Description

Fixing device, optical device, and method of manufacturing optical device

The present disclosure relates to a fixture, an optical device, and a method for manufacturing the optical device for fixing an optical component.

Optical parts used in optical devices such as telescopes need to be fixed with high precision in position and angle. Some are used in various environments such as outer space and cryogenic temperature (see Non-Patent Document 1). As a fixture for fixing an optical component to an optical device with high accuracy, for example, Patent Literature 1 describes a fixture with six degrees of freedom. Patent Document 2 describes that an optical component is positioned and fixed using a position adjusting instrument and then bonded and fixed using an adhesive.

JP 2004-354616 A Japanese Patent Laid-Open No. 5-107433

A fixing device according to an embodiment of the present disclosure is a fixing device that fixes an optical component to a fixing base, the holding component to which the optical component is fixed, the first member to which the holding component is fixed, and the fixing A third member fixed to a base; a second member for connecting and fixing the first member and the third member; the holding component as the first member; and the first member as the second member. And a bolt for fastening the second member to the third member. In addition, a first virtual plane in which the holding component and the first member face each other, a second virtual plane in which the first member and the second member face each other, the second member, and the third member Are not on the same plane as the third virtual planes facing each other.

A fixing device according to an embodiment of the present disclosure is a fixing device that fixes an optical component to a fixing base, the holding component to which the optical component is fixed, the first member to which the holding component is fixed, A fourth member for connecting and fixing the fixing base and the first member, the holding part as the first member, the first member as the fourth member, and the fourth member as the fixing base, respectively. And a bolt to be fastened. A first imaginary plane in which the holding component and the first member oppose each other; a second imaginary plane in which the first member and the fourth member oppose each other; the fourth member and the fixing base; Are not on the same plane as the fourth virtual planes facing each other.

An optical device according to an embodiment of the present disclosure includes the fixing device.

In addition, the method for manufacturing an optical device according to an embodiment of the present disclosure includes a step of positioning an optical component on a stage movable in three different directions, and the positioning of the optical component on three different surfaces. And a step of fixing the stage and the angle to the fixing base with a fixing device whose position and angle can be adjusted, and a step of removing the stage from the optical component.

It is a top view which shows an example of the outline of the optical apparatus of this embodiment. An example of the fixing device of this embodiment is shown, (a) is a perspective view, and (b) is a cross-sectional view taken along the line AA 'in (a). It is a perspective view which shows the optical apparatus of this embodiment, and the stage for positioning an optical component.

The optical device according to the present disclosure will be described with reference to the drawings by taking an optical device for an astronomical telescope as an example. FIG. 1 is a plan view illustrating an example of an outline of the optical device according to the present embodiment.

The optical device 10 includes a slit 20 that allows the electromagnetic wave W from the outside to pass therethrough, a primary mirror 40 and a secondary mirror 50 that reflect the electromagnetic wave W, and a camera 60 that is an imaging unit. The electromagnetic wave W that has passed through the slit 20 is reflected in the order of the primary mirror 40, the secondary mirror 50, and the primary mirror 40, and is guided to the camera 60. Various lenses or mirrors may be arranged between the main mirror 40 and the camera 60. These optical components are each fixed to a fixed base 5 and accommodated in a low temperature holding mechanism (not shown) having a window portion, and temperature fluctuations are suppressed. The electromagnetic wave W that has entered the optical device 10 from the outside travels along the optical path, is imaged by the camera 60, and can analyze information on the observation object.

FIG. 2 shows an example of the fixing device of the present embodiment, (a) is a perspective view, and (b) is a cross-sectional view taken along the line AA 'in (a). As shown in FIG. 2, the fixing device 1 includes a holding component 3 to which an optical component 60 (61) such as a camera, a lens, and a mirror is fixed, a first member 1 a to which the holding component 3 is fixed, and a fixing base 5. A third member 1c fixed to the first member, a second member 1b for connecting and fixing the first member 1a and the third member 1c, the holding component 3, the first member 1a, the second member 1b, and the third member 1c. And a plurality of bolts for fastening the fixing base 5 to each other, and the optical component 61 is fixed to the fixing base 5. That is, the holding component 3 is fixed to the first member 1 a and is not fixed to the other second member 1 b, the third member 1 c, and the fixing base 5. The first member 1 a is fixed to the second member 1 b and is not fixed to the third member 1 c and the fixing base 5. The second member 1b is fixed to the third member 1c and is not fixed to the fixed base 5.

The size of the upper surface of the fixed base 5 is, for example, a length in the X direction of 330 mm to 600 mm and a length in the y direction of 150 mm to 600 mm.

The fixing device 1 includes a first virtual plane 2a in which the holding component 3 and the first member 1a face each other, a second virtual plane 2b in which the first member 1a and the second member 1b face each other, and a second member 1b. And the third virtual plane 2c where the third member 1c faces each other are not on the same plane. By configuring the fixture 1 in such a configuration, the position and angle of the optical component 60 (61) can be highly accurately within the three planes of the first virtual plane 2a, the second virtual plane 2b, and the third virtual plane 2c. Can be adjusted. That is, the optical component 60 (61) arranged with three-dimensional degrees of freedom can be fixed to the fixed base 5 by absorbing the directions of a total of six axes including the three directions and the three in-plane angles. The first virtual plane 2a, the second virtual plane 2b, and the third virtual plane 2c are not on the same plane. The first virtual plane 2a and the second virtual plane 2b intersect with each other instead of being parallel. The second virtual plane 2b and the third virtual plane 2c intersect each other rather than in parallel, and the first virtual plane 2a and the third virtual plane 2c intersect each other rather than in parallel. .

The fixing device 1 can fix the optical component 60 (61) with high accuracy and can be used in various environments such as outer space and cryogenic temperature. In the conventional 6-degree-of-freedom fixing device shown in Patent Document 1, there is a risk that the position and angle may be shifted when the optical component is fixed, and the accuracy may deteriorate. However, in the fixing device 1 of the present disclosure, the optical component 60 (61 ) Can be fixed with high accuracy. Further, in the 6-degree-of-freedom fixing device shown in Patent Document 1, there is a fear that the device may be loosened and the position and angle of the optical component may change after the optical component is fixed. Even after fixing 60 (61), it is possible to reduce the change in the position and angle of the optical component 60 (61). Moreover, in the fixing device which fixed the optical component using the adhesive shown in the conventional patent document 2, there is a concern about the reliability of the adhesive, and the performance is likely to deteriorate in an environment such as outer space and cryogenic temperature. In the fixing device 1 of the present disclosure, the performance is unlikely to deteriorate even in an environment such as outer space and cryogenic temperature.

Further, as another embodiment of the fixed component, in FIG. 2, the second member 1b and the third member 1c may be regarded as one fourth member. In this case, the first virtual plane 2a in which the holding component 3 and the first member 1a oppose each other, the second virtual plane 2b in which the first member 1a and the fourth member oppose each other, the fourth member, and the fixing base 5 Are not on the same plane as the fourth virtual plane 2d facing each other. By configuring the fixture 1 in such a configuration, the position and angle of the optical component 60 (61) can be highly accurately within the three planes of the first virtual plane 2a, the second virtual plane 2b, and the fourth virtual plane 2d. Can be adjusted. That is, the optical component 60 (61) arranged with three-dimensional degrees of freedom can be fixed to the fixed base 5 by absorbing the directions of a total of six axes including the three directions and the three in-plane angles. The first virtual plane 2a, the second virtual plane 2b, and the fourth virtual plane 2d are not coplanar. The first virtual plane 2a and the second virtual plane 2b intersect each other instead of being parallel. The second virtual plane 2b and the fourth virtual plane 2d intersect with each other instead of being parallel, and the first virtual plane 2a and the fourth virtual plane 2d intersect with each other instead of being parallel. .

The holding component 3, the first member 1a, the second member 1b, and the third member 1c have through holes for passing bolts. For example, the first virtual plane 2a is a boundary surface, the first member 1a is a through hole, the holding component 3 is a screw hole, the second virtual plane 2b is a boundary surface, the second member 1b is a through hole, and the first member 1a is With the screw hole and the third virtual plane 2c as a boundary surface, a through hole is formed in the second member 1b, a screw hole is formed in the third member 1c, a through hole 1e is formed in the third member 1c, and a screw hole 1f is formed in the fixing base 5. Fasten with bolts.

In addition, in FIG.2 (b), although the case where the 3rd member 1c is fastened with the volt | bolt 1d to the fixing stand 5 is shown, it is the same also when fastening other members.

At this time, the outer diameter of the bolt is 0.1 mm to 10 mm, particularly preferably 0.5 mm to 1 mm smaller than the inner diameter of the through hole. With such a setting, when each component constituting the fixture 1 is fastened with a bolt, each of the first virtual plane 2a, the second virtual plane 2b, the third virtual plane 2c, and the fourth virtual plane 2d Within the plane, the position of the optical component 60 (61) can be adjusted within a range of 0.1 mm to 10 mm or 0.5 mm to 1 mm. The screw hole 1f is, for example, an internal space formed by a coil insert. When the coil insert is used, the bolt is fastened to the coil insert with a washer interposed therebetween.

Further, the facing surfaces of the holding component 3, the first member 1a, the second member 1b, and the third member 1c that are opposed to each other preferably have an open porosity of 0.5 area% or less.

If the open porosity is within the above range, the possibility of floating fine particles invading into the open pores is reduced, so that highly accurate positioning is facilitated.

Furthermore, the average diameter of the open pores on the facing surface is preferably 3 μm or less, and the maximum diameter is preferably 10 μm or less.

If the average diameter and the maximum diameter of the open pores are within the above range, the possibility that large floating fine particles enter the open pores is reduced, and it becomes easier to perform positioning with higher accuracy.

In order to obtain the open porosity, the average diameter and the maximum diameter of the open pores, polishing is performed with a copper disk using diamond abrasive grains having an average particle diameter D50 of 3 μm in the depth direction from the surface of the member to be observed. Then, it grind | polishes with a tin disc using the diamond abrasive grain whose average particle diameter D50 is 0.5 micrometer. A polished surface obtained by such polishing is used as an observation surface.

Then, using an optical microscope, the magnification of the observation surface is set to 100 times, and the measurement object is photographed at four places, for example, the horizontal length is 720 μm and the vertical length is 540 μm. Next, in the photographed image, a region excluding the peripheral part (area is 226856 μm ² ) is set as a measurement range, and measurement is performed at four locations using image analysis software (for example, Win ROOF, manufactured by Mitani Corporation). By analyzing the range, the equivalent circle diameter of the pores can be obtained.

In addition, the threshold value of the equivalent circle diameter of the open pores may be 0.868 μm.

Further, the holding component 3, the first member 1a, the second member 1b, and the third member 1c may have a rectangular parallelepiped shape, for example.

At least one of the holding component 3, the first member 1 a, the second member 1 b, and the third member 1 c has an average linear expansion coefficient of ± 1.5 × 10 ⁻⁶ / K from the use temperature (for example, 10 K or less) to room temperature It consists of the following ceramics or glass. Examples of such ceramics include ceramics mainly composed of cordierite, lithium aluminosilicate, potassium zirconium phosphate or mullite.

The ceramics in which cordierite is the main component include Ca in the range of 0.4 to 0.6% by mass in terms of CaO, Al in the range of 2.3 to 3.5% by mass in terms of Al ₂ O ₃ and Mn. and Cr may include MnCr ₂ O ₄ 0.7 wt% to 0.6 wt% in terms of the following. This ceramic can have an average coefficient of linear expansion of ± 20 × 10 ⁻⁹ / K or less.

The ceramic whose main component is lithium aluminosilicate may contain 20% by mass or less of silicon carbide.

Also, as an example of glass, glass mainly composed of titanium silicate can be given. If a member made of ceramics or glass having a small average linear expansion coefficient is used, since the change in shape is small even when exposed to a large temperature change, the member has high reliability.

Here, when at least one of the holding component 3, the first member 1a, the second member 1b, and the third member 1c is made of ceramics, the average linear expansion coefficient of the members made of ceramics in accordance with JIS R 1618: 2002. You can ask for.

When at least one of the holding component 3, the first member 1a, the second member 1b, and the third member 1c is made of glass, the average linear expansion coefficient of the member made of glass is obtained in accordance with JIS R 3251: 1995. Good.

In addition, what is necessary is just to measure using the optical heterodyne method 1 optical path interferometer, when the average linear expansion coefficient of each member is +/- ^1x10 < ^-6 > / K or less.

The main component in ceramic refers to a component occupying 60% by mass or more out of a total of 100% by mass of components constituting the target ceramic. In particular, the main component may be a component that occupies 95% by mass or more out of a total of 100% by mass of the components constituting the target ceramic. What is necessary is just to obtain | require the component which comprises ceramics using an X-ray-diffraction apparatus (XRD). The content of each component is obtained by identifying the component, then obtaining the content of the element constituting the component using an X-ray fluorescence analyzer (XRF) or an ICP emission spectroscopic analyzer, and converting it to the identified component. Good. The same applies to glass.

The bolt may be made of at least one of an iron-cobalt alloy, an iron-cobalt-carbon alloy, an iron-nickel alloy, and an iron-nickel-cobalt alloy.

This is because such an alloy has an average coefficient of linear expansion close to that of ceramics.

In particular, the bolt may be made of a low thermal expansion metal such as iron-36 wt% nickel alloy (trade name is Invar (registered trademark, Imphy Alloys)). The coil insert and washer used for fastening with the bolt may be stainless steel such as SUS304, SUS304L, SUS304N1, SUS304N2, SUS316, SUS317, SUS312L, SUS329J1 or SUS329J4L. This is because these stainless steels have high corrosion resistance.

With the above configuration, the optical component 60 (61) can be fixed to the fixing base 5 with high accuracy, for example, with an accuracy of 1 μm or less, using the fixing device 1.

In particular, the holding component 3, the first member 1a, the second member 1b, and the third member 1c all have an average linear expansion coefficient of ± 1.5 × 10 ⁻⁶ / K or less from the use temperature (for example, 10K or less) to room temperature. It may be made of ceramics or glass.

The optical device of the present disclosure includes a fixing device 1, and the optical device 10 illustrated in FIG. 3 includes an optical component 60, the fixing device 1, and a fixing base 5 that supports the fixing device 1. Is about 600 mm × 600 mm × 600 mm. In the present embodiment, the fixture 1 is housed in the low temperature holding mechanism together with the optical component 60. Therefore, it is preferable that the fixing device 1 is comprised from the above low thermal expansion materials.

FIG. 3 is a perspective view showing the optical device of the present embodiment and a stage for positioning optical components.

A method for manufacturing the optical device 10 of the present disclosure will be described with reference to FIG. In the method of manufacturing the optical device 10 according to the present disclosure, the optical component 60 (61) is attached to the stage 6 that is movable in three different directions and positioned, and the positioned optical component 60 (61) is different in three. There are a step of fixing to the fixing base 5 with a fixing device 1 whose position and angle can be adjusted in one plane, and a step of removing the stage 6 from the optical component 60 (61).

As the fixing device 1, the fixing device 1 of the present disclosure is suitable.

Hereinafter, details of the method of manufacturing the optical device 10 of the present disclosure will be described using the fixing device 1 illustrated in FIG. 1 as an example. The optical component 60 (61) such as a camera is on the optical path of the electromagnetic wave W reflected by the primary mirror 40 and the secondary mirror 50, and its position and angle need to be accurately fixed. Specifically, it is required to arrange three-dimensionally at a submicron level position and at an angle of several seconds or less.

First, the primary mirror 40 and the secondary mirror 50 are fixed at predetermined positions of the fixed base 5.

Next, the holding component 3 is attached to a stage 6 that can move in three different directions. Here, the holding component 3 is, for example, a camera base. The three different directions are the X direction, the Y direction, and the Z direction shown in FIG. 3, and are the three directions orthogonal to each other. The stage 6 is, for example, a high-precision XYZ stage that enables the holding component 3 to move in three orthogonal directions. As the stage 6, an XY axis stage 6a (for example, TSD-602SLWP manufactured by Sigma Koki Co., Ltd.) and a Z axis stage 6b (manufactured by Sigma Koki Co., Ltd., TSD-603RLWP) can be used in combination. The holding component 3 is attached to the stage 6 in a state where adjustment in a direction substantially parallel to the optical axis of the electromagnetic wave W and two directions perpendicular thereto can be performed.

Next, the holding part 3 is positioned using the stage 6. For positioning, for example, a mirror (collation mirror) 61 is mounted on the holding component 3 before the camera 60 is mounted, and a He-Ne laser is used to enter the main mirror 40 and the mirror (collation mirror) 61. Then, the interference with the light reflected from the primary mirror 40 is measured with an optical interferometer, and the holding component 3 may be set at a desired position and angle. For example, the angle formed by both reflected waves when a parallel electromagnetic wave W is incident is adjusted to be within 2 seconds. When the optical axis height of the interferometer and the optical device 10 does not match, the direction of the optical device 10 is appropriately rotated to measure the interference between the light incident on the primary mirror 40 and the light reflected from the primary mirror 40. May be.

Next, the third member 1c and the fixing base 5 are connected with bolts 1d.

Next, the first member 1a is temporarily fixed to the holding component 3 with bolts in a state where the position and angle can be adjusted in the first virtual plane 2a. Similarly, the second member 1b and the third member 1c, and the first member 1a and the second member 1b are temporarily fixed in the second imaginary plane 2b and the third imaginary plane 2c, respectively, in a state where the position and angle can be adjusted. The order of temporary fixing of the first member 1a, the second member 1b, and the third member 1c is not particularly limited.

Next, the first member 1a and the holding component 3, the second member 1b and the third member 1c, the first member 1a and the second member 1b are finally tightened with bolts, and the holding component 3 is fixed to the first member 1a and the second member 1b. The member 1b and the third member 1c are fixed to the fixing base 5 sequentially. Here, the order of the final fastening of the first member 1a, the second member 1b, and the third member 1c is not particularly limited.

姿勢 Fine adjustment of the posture of the holding part 3 is possible by temporarily fixing before final tightening. Moreover, the stress applied at the time of fastening of the fixing device 1 can be reduced, and breakage of the fixing device 1 can be suppressed.

Then, the stage 6 is removed from the holding part 3, the mirror (collation mirror) 61 is removed, and the camera 60 is attached. The stage 6 is removed because the stage 6 is made of a material having a high linear expansion coefficient, for example, steel.

The embodiments of the present disclosure have been described above. However, the present disclosure is not limited to the above-described embodiments, and various modifications, improvements, combinations, and the like can be made without departing from the scope of the present disclosure.

DESCRIPTION OF SYMBOLS 1 Fixing tool 1a 1st member 1b 2nd member 1c 3rd member 1d Bolt 1e Through-hole 1f Screw hole 2a 1st virtual plane 2b 2nd virtual plane 2c 3rd virtual plane 2d 4th virtual plane 3 Holding component 5 Fixing base 6 Stage 10 Optical device 20 Slit 40 Primary mirror 50 Secondary mirror 60 Optical component (camera)
61 Optical parts (mirrors)

Claims

A fixing device for fixing an optical component to a fixing base,
A holding part to which the optical part is fixed;
A first member to which the holding component is fixed;
A third member fixed to the fixed base;
A second member for connecting and fixing the first member and the third member;
A bolt for fastening the holding component to the first member, the first member to the second member, and the second member to the third member;
A first imaginary plane in which the holding component and the first member face each other;
A second imaginary plane in which the first member and the second member oppose each other;
A fixing device in which the second virtual plane and the third member facing each other are not on the same plane.
At least one of the holding part, the first member, the second member, and the third member is made of ceramic or glass having an average linear expansion coefficient of ± 1.5 × 10 −6 / K or less, and the bolt is The fixing device according to claim 1, comprising at least one of iron-cobalt alloy, iron-cobalt-carbon alloy, iron-nickel alloy, and iron-nickel-cobalt alloy.
2. The facing surfaces of the holding component, the first member, the second member, and the third member facing each other have an open porosity of 0.5 area% or less (excluding 0 area%). Or the fixing device of 2.
The holding component, the first member, the second member, and the third member have a through hole through which the bolt passes, and the outer diameter of the bolt is 0.1 mm to 10 mm larger than the inner diameter of the through hole. The fixing device according to any one of claims 1 to 3, which is small.
A fixing device for fixing an optical component to a fixing base,
A holding part to which the optical part is fixed;
A first member to which the holding component is fixed;
A fourth member for connecting and fixing the fixing base and the first member;
A bolt for fastening the holding component to the first member, the first member to the fourth member, and the fourth member to the fixing base,
A first imaginary plane in which the holding component and the first member face each other;
A second imaginary plane in which the first member and the fourth member oppose each other;
The fourth fixture and the fourth imaginary plane on which the fixing base faces each other are not on the same plane.
At least one of the holding part, the first member, and the fourth member is made of ceramic or glass having an average linear expansion coefficient of ± 1.5 × 10 −6 / K or less, and the bolt is made of iron-cobalt The fixing device according to claim 5, comprising at least one of an alloy, an iron-cobalt-carbon alloy, an iron-nickel alloy, and an iron-nickel-cobalt alloy.
The facing surfaces of the holding component, the first member, and the fourth member facing each other have an open porosity of 0.5 area% or less (excluding 0 area%). Fixing device.
The holding part, the first member, and the fourth member have a through hole through which the bolt passes, and an outer diameter of the bolt is 0.1 mm to 10 mm smaller than an inner diameter of the through hole. The fixing device according to any one of 1 to 7.
An optical device comprising the fixing device according to any one of claims 1 to 8.
Attaching and positioning the optical component on a stage movable in three different directions;
Fixing the positioned optical component to a fixing base with a fixing device whose position and angle can be adjusted in three different planes;
Removing the stage from the optical component,
Manufacturing method of optical device.
Attaching and positioning the optical component on a stage movable in three different directions;
Fixing the positioned optical component to a fixing base with the fixing device according to any one of claims 1 to 8,
Removing the stage from the optical component,
Manufacturing method of optical device.