WO2020202696A1 - Method for manufacturing optical element - Google Patents

Method for manufacturing optical element Download PDF

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Publication number
WO2020202696A1
WO2020202696A1 PCT/JP2020/001007 JP2020001007W WO2020202696A1 WO 2020202696 A1 WO2020202696 A1 WO 2020202696A1 JP 2020001007 W JP2020001007 W JP 2020001007W WO 2020202696 A1 WO2020202696 A1 WO 2020202696A1
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WIPO (PCT)
Prior art keywords
support
optical element
cutting
manufacturing
polishing
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PCT/JP2020/001007
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French (fr)
Japanese (ja)
Inventor
光樹夫 栗田
司 荻野
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株式会社ロジストラボ
国立大学法人京都大学
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Publication of WO2020202696A1 publication Critical patent/WO2020202696A1/en

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B13/00—Machines or devices designed for grinding or polishing optical surfaces on lenses or surfaces of similar shape on other work; Accessories therefor
    • B24B13/005—Blocking means, chucks or the like; Alignment devices
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B13/00—Machines or devices designed for grinding or polishing optical surfaces on lenses or surfaces of similar shape on other work; Accessories therefor
    • B24B13/04—Machines or devices designed for grinding or polishing optical surfaces on lenses or surfaces of similar shape on other work; Accessories therefor grinding of lenses involving grinding wheels controlled by gearing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B41/00—Component parts such as frames, beds, carriages, headstocks
    • B24B41/06—Work supports, e.g. adjustable steadies
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B3/00—Simple or compound lenses
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/08—Mirrors

Definitions

  • the present invention relates to a method for manufacturing an optical element.
  • Patent Document 1 discloses a method of forming an aspherical mirror by deforming the material of the aspherical mirror by applying a force to the ring in a state where the material of the aspherical mirror is housed inside the ring. In this method, an aspherical mirror having a desired shape is formed by releasing the force applied to the ring after deforming it into an aspherical shape and then removing a minute region near the outer circumference.
  • Non-Patent Document 1 discloses an SMP (Stressed Mirror Polishing) method in which a stress is applied to the edge of a disk-shaped material to polish the material in a state where the disk-shaped glass is bent.
  • SMP Structured Mirror Polishing
  • a polishing pad is placed inside the ring in a state where the material is housed in a ring having a size substantially equal to the size of the aspherical mirror to be formed. Polish the material by rotating.
  • the magnitude of the force applied to the material differs between the region near the center of the polishing pad and the region near the outer circumference. Therefore, there is a difference in the magnitude of the force applied to the material between the region near the center of the material that the region near the center of the polishing pad contacts and the region outside the material that the region near the center of the polishing pad does not contact.
  • the variation of the force applied to the vicinity of the outer edge of the material becomes large and the polishing accuracy of the surface in the vicinity of the outer edge is lowered.
  • Non-Patent Document 1 there is a problem that a complicated mechanism is required to apply stress to the material to be polished. Further, there is also a problem that it is necessary to perform additional processing using an ion beam in order to repair the deformation that occurs when the stress is released after polishing.
  • an object of the present invention is to provide a method for manufacturing an optical element by forming a surface with high accuracy without applying stress and bending the material.
  • the method for manufacturing an optical element of the present invention includes a mounting step of mounting the material on a plurality of supports supporting the material of the optical element, and a cutting position corresponding to the contour line of the optical element using a polishing pad. It has a polishing step of polishing the material to a position outside the radius of at least the polishing pad, and a cutting step of cutting the material at the cutting position after the polishing step.
  • the material is supported by a plurality of inner supports provided in the region inside the cutting position in the material and a plurality of outer supports provided in the region outside the cutting position.
  • the material may be placed on the surface.
  • the material may be polished with the plurality of outer supports supporting the material at the position.
  • the support reaction force generated at each of the plurality of support positions while the plurality of inner supports support the material is generated at each of the plurality of support positions when the optical element is installed on the telescope.
  • the material may be polished in a state where the plurality of outer supports support the material so as to be equal to the reaction force generated in.
  • the optical element is installed in the telescope by a support reaction force generated at each of the plurality of support positions in a state where the plurality of inner supports support the material before the above-described setting step.
  • the support position determination step of determining the support reaction force at each of the plurality of support positions and the plurality of support positions using the finite element method is performed so as to be equal to the reaction force generated at each of the plurality of support positions in the state. You may also have more.
  • the material may be placed so that the positions of the plurality of supports are symmetrical with respect to the center line of the material.
  • the manufacturing method further includes a step of covering the material with a protective film between the polishing step and the cutting step, and in the cutting step, the cutting position of the material covered with the protective film.
  • the material may be cut by injecting pressurized water into the material.
  • an optical element can be manufactured by forming a surface with high accuracy without applying stress and bending the material.
  • FIG. 1 is a diagram for explaining an outline of the manufacturing method M of the optical element 1 according to the present embodiment.
  • the optical element 1 is, for example, an aspherical optical element having an aspherical surface, and is a mirror used in a large telescope.
  • the manufacturing method M is a method for manufacturing an optical element 1 having an aspherical surface by polishing a material 2 having a flat surface.
  • the material 2 shown in FIG. 1 is a plate having a straight side and a curved side, but the shape of the material 2 is arbitrary and may be polygonal or circular.
  • the size of the material 2 is arbitrary, but for example, the longer width is 1000 mm or more, and the material 2 has a thickness of about 10 mm to 100 mm.
  • the material of the material 2 is, for example, glass, ceramics, resin or metal.
  • the material 2 larger than the optical element 1 to be manufactured is polished, and then the material 2 is cut at the cutting position C corresponding to the contour line of the optical element 1 to obtain the optical element. 1 is manufactured.
  • the distance from the cutting position C to the outer edge of the material 2 is at least equal to or greater than the radius of the polishing pad used for polishing. It is more preferable that the distance from the cutting position C to the outer edge of the material 2 is equal to or larger than the diameter of the polishing pad (that is, twice or more the radius).
  • the diameter of the polishing pad is, for example, 100 mm.
  • the optical element 1 Since the distance from the cutting position C to the outer edge of the material 2 is equal to or greater than the radius of the polishing pad, the optical element 1 is polished under the same conditions as the inside of the cutting position C even at the peripheral position of the cutting position C. Sufficient polishing accuracy can be ensured in all areas.
  • polishing is performed under the same conditions as the inside of the cutting position C, so that the polishing accuracy can be further improved.
  • FIG. 2 is a diagram for explaining details of a method for manufacturing the optical element 1.
  • FIG. 3 is a flowchart showing a process of manufacturing the optical element 1.
  • FIG. 2A is a schematic view showing a state in which the material 2 being polished is viewed from the side of the surface to be polished.
  • FIG. 2B is a schematic view showing a state in which the material 2 being polished is viewed from the side.
  • the minimum value D of the distance between the cutting position C and the outer edge is equal to or greater than the radius R of the polishing pad 20.
  • the method for manufacturing the optical element 1 will be described in detail with reference to FIGS. 2 and 3.
  • the material 2 is polished while the material 2 is supported by a plurality of supports. Specifically, a plurality of inner supports 11 (indicated by black circles in FIG. 2A) provided in the region r1 inside the cutting position C in the material 2, and the region r2 outside the cutting position C.
  • the material 2 is polished while the material 2 is supported by a plurality of outer supports 12 (indicated by white circles in FIG. 2A) provided in the above.
  • 10 inner supports 11 are provided in the region r1 and 12 outer supports 12 are provided in the region r2.
  • FIG. 2B only a part of the inner support 11 and the outer support 12 are schematically shown.
  • the inner support 11 and the outer support 12 are elastic objects, and have, for example, a spring, a hydraulic cylinder, an air cylinder, or an elastic resin.
  • the inner support 11 and the outer support 12 are preferably objects whose support position (for example, length) and the magnitude of the support reaction force can be adjusted.
  • the elastic force of each inner support 11 is such that the support reaction force generated at each support position of the plurality of inner supports 11 is equal to the reaction force generated at each support position when the optical element 1 is installed on the telescope. It is designed to be.
  • the support reaction force generated at each of the plurality of support positions when the plurality of inner supports 11 support the material 2 is generated at the plurality of support positions when the optical element 1 is installed on the telescope.
  • the support position determination step is executed before the polishing step is executed (S1).
  • the support position is represented, for example, as a position relative to the position of the center of gravity of the material.
  • a finite element method is used to determine a plurality of support positions and support reaction forces (that is, elastic forces of the inner support 11 and the outer support 12) at each of the plurality of support positions. ..
  • the support position is represented by the distance and direction from the origin, for example, with the fixed position as the origin and the direction of the line connecting the two fixed positions as the reference direction.
  • the support position may be represented by the distance and direction from the center of gravity of the material 2.
  • the position of the inner support 11 in the region r1 is determined, and then the position of the outer support 12 in the region r2 is determined.
  • at least three are fixed points (outer supports 12A, 12B, 12C in the example shown in FIG. 2) in which the height of the support is fixed.
  • a metal rod is provided at the fixed point. It is preferable that the fixing point is provided at a position as close to the outer edge of the material 2 as possible.
  • the position of the inner support 11 in the region r1 it is finite so that the deformation due to its own weight when the completed optical element 1 (that is, the mirror after cutting from the material 2) is mounted on the telescope is sufficiently small. Analyze using the element method. Once the position of the inner support 11 is determined, the support reaction force of each inner support 11 is calculated by analysis using the finite element method.
  • the finite element method is performed so that the deformation due to the own weight of the region r1 is sufficiently small while the support reaction force of the inner support 11 is at a predetermined value.
  • a plurality of outer supports 12 are added to the region r2 by analysis using. Once the position of the outer support 12 is determined, the support reaction force of each outer support 12 is calculated by analysis using the finite element method.
  • a plurality of positions (hereinafter referred to as a plurality of measurement positions) of the optical elements measured in a state where the optical elements having the same shape as the optical element 1 to be manufactured are installed in the telescope. ), Measurement data indicating the magnitude of the reaction force may be acquired.
  • the magnitude of the reaction force at the plurality of measurement positions is equal to the value indicated by the acquired measurement data.
  • the positions and elastic forces of the plurality of inner supports 11 and the positions and elastic forces of the plurality of outer supports 12 are searched for. A plurality of inner supports 11 and a plurality of outer supports 12 having the elastic force determined in this manner are prepared, and the plurality of inner supports 11 and the plurality of outer supports 12 are installed at the determined support positions.
  • the positions where the plurality of inner supports 11 are installed are before and after the material 2 is cut, and the changes in the supporting reaction forces that occur at each of the plurality of positions where the plurality of inner supports 11 support the material 2 are relative. It is preferable that the position is small.
  • the material 2 is supported by the plurality of inner supports 11 and the plurality of outer supports 12 in the state before cutting shown in FIG. 1A.
  • the support reaction force generated at each of the plurality of support positions during the process is compared with the support reaction force generated at each of the plurality of support positions in the state after cutting shown in FIG. 1 (c).
  • the positions where the plurality of inner supports 11 and the plurality of outer supports 12 are installed are determined so that the difference between the support reaction force before cutting and the support reaction force after cutting is minimized.
  • the material 2 After installing the plurality of inner supports 11 and the plurality of outer supports 12 at the determined support positions, the material 2 is placed so that the material 2 is supported by the plurality of inner supports 11 and the plurality of outer supports 12.
  • the mounting step is executed (S2). At this time, the material 2 is placed so that the positions of the plurality of inner supports 11 and the plurality of outer supports 12 are symmetrical with respect to the center line of the material 2. By placing the material 2 in this way, it becomes easy to place the material 2 at a predetermined position with high accuracy.
  • the polishing step is executed with the material 2 supported by the plurality of inner supports 11 and the plurality of outer supports 12 (S3).
  • the support reaction force generated at each of the plurality of support positions while the plurality of inner supports 11 support the material 2 is applied to each of the plurality of support positions when the optical element 1 is installed on the telescope.
  • the material 2 is polished with the plurality of outer supports 12 supporting the material 2 so as to be equal to the generated reaction force. Further, in the polishing step, at a position where the change in the supporting reaction force generated at each of the plurality of supporting positions where the plurality of inner supports 11 support the material 2 is relatively small before and after cutting the material 2.
  • the material 2 may be polished with the plurality of outer supports 12 supporting the material 2.
  • the polishing pad 20 is rotated and moved over the entire area of the material 2.
  • the radius R of the polishing pad 20 is smaller than the minimum value of the distance between the cutting position C and the outer edge of the material 2 (for example, D shown in FIG. 2A). Therefore, by moving the polishing pad 20 to the vicinity of the outer edge of the material 2, polishing can be performed in a state where the center position of the polishing pad 20 is in contact with the position of the cutting position C. Therefore, the cutting position can be obtained even in the vicinity of the cutting position C.
  • the material 2 can be polished under the same conditions as the region r1 inside C.
  • the material 2 is cut at the cutting position C.
  • a protective film forming step of covering the material 2 with a protective film before cutting the material 2 (S4).
  • a protective film containing fluorine is applied to the material 2 by spraying to form a protective film.
  • a cutting step of cutting the material 2 at the cutting position C is executed (S5).
  • the method of cutting the material 2 is arbitrary, but in order to reduce the stress applied to the material 2, the material 2 is sprayed with pressurized water at the cutting position C in the material 2 covered with the protective film. It is preferable to use a water jet method for cutting.
  • FIG. 4 is a diagram for explaining the effect of manufacturing the optical element 1 by using the manufacturing method M.
  • FIG. 4A is a diagram showing the flatness near the outer edge of the optical element 1 manufactured by the manufacturing method M, and the shading corresponds to the thickness of the optical element 1. The smaller the difference in shade, the greater the flatness.
  • FIG. 4B is a diagram showing the flatness near the outer edge of the optical element manufactured by polishing a material having the same shape as the final shape of the optical element to be manufactured. Comparing FIG. 4A and FIG. 4B, the change in shading in FIG. 4A is much smaller than the change in shading in FIG. 4B, and the optical element using the manufacturing method M is used. It can be seen that the flatness of the optical element 1 is improved by manufacturing 1.
  • the polishing pad 20 is used to reach a position at least outside the radius of the polishing pad 20 from the cutting position C corresponding to the contour line of the optical element 1.
  • the optical element 1 is manufactured by cutting the material 2 at the cutting position C.
  • the vicinity of the center of the polishing pad 20 also comes into contact with the vicinity of the cutting position C, so that the material 2 is polished under the same conditions as the region r1 inside the cutting position C even in the vicinity of the cutting position C. be able to.
  • the manufacturing method M by manufacturing the optical element 1 by using the manufacturing method M, it is possible to improve the processing accuracy in the vicinity of the outer edge of the optical element 1 without applying stress to the material 2 and bending the material 2. As a result, according to the manufacturing method M, it is possible to manufacture the high quality optical element 1 at low cost.
  • the manufacturing method M may be applied to the manufacturing of the optical element having a spherical surface.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Grinding And Polishing Of Tertiary Curved Surfaces And Surfaces With Complex Shapes (AREA)
  • Optical Elements Other Than Lenses (AREA)
  • Constituent Portions Of Griding Lathes, Driving, Sensing And Control (AREA)

Abstract

An optical element 1 manufacturing method that has: a placement step in which a raw material 2 of an optical element 1 is placed on a plurality of support bodies 11, 12 that support the raw material 2; a polishing step in which a polishing pad 20 is used and the raw material 2 is polished to at least a position further on the outside, by the radius of the polishing pad 20, than a cutting position C corresponding to an contour of the optical element 1; and a cutting step in which the raw material 2 is cut at the cutting position C after the polishing step.

Description

光学素子の製造方法Manufacturing method of optical element
　本発明は、光学素子を製造する方法に関する。 The present invention relates to a method for manufacturing an optical element.
　大型の望遠鏡には、高精度の非球面鏡が搭載されている。特許文献１には、非球面鏡の素材をリングの内側に収容した状態でリングに力を加えて非球面鏡の素材を変形させることにより非球面形状の鏡を成形する方法が開示されている。当該方法においては、非球面形状に変形させた後にリングに加えた力を解放し、その後、外周の近傍の微小領域を除去することにより所望の形状の非球面鏡が形成される。 The large telescope is equipped with a high-precision aspherical mirror. Patent Document 1 discloses a method of forming an aspherical mirror by deforming the material of the aspherical mirror by applying a force to the ring in a state where the material of the aspherical mirror is housed inside the ring. In this method, an aspherical mirror having a desired shape is formed by releasing the force applied to the ring after deforming it into an aspherical shape and then removing a minute region near the outer circumference.
　また、非特許文献１には、円盤状の素材の縁にストレスを加えて、円盤状のガラスを曲げた状態で素材を研磨するＳＭＰ（Stressed Mirror Polishing）法が開示されている。 Further, Non-Patent Document 1 discloses an SMP (Stressed Mirror Polishing) method in which a stress is applied to the edge of a disk-shaped material to polish the material in a state where the disk-shaped glass is bent.
特開２０１０－００６６９３号公報JP-A-2010-006693
　特許文献１に記載された方法においては、除去される素材を少なくするために、形成する非球面鏡の大きさとほぼ等しい大きさのリング内に素材が収容された状態で、リングの内側で研磨パッドを回転させることにより素材を研磨する。ところが、研磨パッドの中心付近の領域と外周付近の領域とでは、素材に加わる力の大きさが異なる。したがって、研磨パッドの中心付近の領域が接触する素材の中央付近の領域と、研磨パッドの中心付近の領域が接触しない素材の外側の領域とでは、素材に加わる力の大きさに差が生じる。その結果、素材の外縁付近に加わる力のばらつきが大きくなり、外縁付近における表面の研磨精度が低下してしまうという問題があった。 In the method described in Patent Document 1, in order to reduce the amount of material to be removed, a polishing pad is placed inside the ring in a state where the material is housed in a ring having a size substantially equal to the size of the aspherical mirror to be formed. Polish the material by rotating. However, the magnitude of the force applied to the material differs between the region near the center of the polishing pad and the region near the outer circumference. Therefore, there is a difference in the magnitude of the force applied to the material between the region near the center of the material that the region near the center of the polishing pad contacts and the region outside the material that the region near the center of the polishing pad does not contact. As a result, there is a problem that the variation of the force applied to the vicinity of the outer edge of the material becomes large and the polishing accuracy of the surface in the vicinity of the outer edge is lowered.
　また、非特許文献１に記載されたＳＭＰ法においては、研磨する対象となる素材にストレスを加えるために複雑な機構が必要になるという問題があった。さらに、研磨後にストレスを解放した際に生じる変形を補修するために、イオンビームを用いて追加工する必要があるという問題もあった。 Further, in the SMP method described in Non-Patent Document 1, there is a problem that a complicated mechanism is required to apply stress to the material to be polished. Further, there is also a problem that it is necessary to perform additional processing using an ion beam in order to repair the deformation that occurs when the stress is released after polishing.
　そこで、本発明はこれらの点に鑑みてなされたものであり、ストレスを加えて素材を曲げることなく高精度に面を形成して光学素子を製造する方法を提供することを目的とする。 Therefore, the present invention has been made in view of these points, and an object of the present invention is to provide a method for manufacturing an optical element by forming a surface with high accuracy without applying stress and bending the material.
　本発明の光学素子の製造方法は、光学素子の素材を支持する複数の支持体に前記素材を載置する載置工程と、研磨パッドを用いて、前記光学素子の輪郭線に対応する切断位置よりも少なくとも前記研磨パッドの半径以上外側の位置まで前記素材を研磨する研磨工程と、前記研磨する工程の後に、前記切断位置で前記素材を切断する切断工程と、を有する。 The method for manufacturing an optical element of the present invention includes a mounting step of mounting the material on a plurality of supports supporting the material of the optical element, and a cutting position corresponding to the contour line of the optical element using a polishing pad. It has a polishing step of polishing the material to a position outside the radius of at least the polishing pad, and a cutting step of cutting the material at the cutting position after the polishing step.
　前記載置工程において、前記素材における前記切断位置の内側の領域に設けられた複数の内側支持体、及び前記切断位置の外側の領域に設けられた複数の外側支持体で前記素材を支持するように前記素材を載置してもよい。 In the pre-described step, the material is supported by a plurality of inner supports provided in the region inside the cutting position in the material and a plurality of outer supports provided in the region outside the cutting position. The material may be placed on the surface.
　前記研磨工程において、前記切断工程において前記素材を切断する前と後とで、前記複数の内側支持体が前記素材を支持する複数の支持位置それぞれに生じる支持反力の変化が相対的に小さくなる位置において前記複数の外側支持体が前記素材を支持する状態で前記素材を研磨してもよい。 In the polishing step, the change in the support reaction force generated at each of the plurality of support positions where the plurality of inner supports support the material becomes relatively small before and after cutting the material in the cutting step. The material may be polished with the plurality of outer supports supporting the material at the position.
　前記研磨工程において、前記複数の内側支持体が前記素材を支持している状態で複数の支持位置それぞれに生じる支持反力が、前記光学素子が望遠鏡に設置された状態で前記複数の支持位置それぞれに生じる反力と等しくなるように前記複数の外側支持体が前記素材を支持する状態で前記素材を研磨してもよい。 In the polishing step, the support reaction force generated at each of the plurality of support positions while the plurality of inner supports support the material is generated at each of the plurality of support positions when the optical element is installed on the telescope. The material may be polished in a state where the plurality of outer supports support the material so as to be equal to the reaction force generated in.
　前記製造方法は、前記載置工程の前に、前記複数の内側支持体が前記素材を支持している状態で前記複数の支持位置それぞれに生じる支持反力が、前記光学素子が望遠鏡に設置された状態で前記複数の支持位置それぞれに生じる反力と等しくなるように、有限要素法を用いて前記複数の支持位置と、前記複数の支持位置それぞれにおける支持反力を決定する支持位置決定工程をさらに有してもよい。 In the manufacturing method, the optical element is installed in the telescope by a support reaction force generated at each of the plurality of support positions in a state where the plurality of inner supports support the material before the above-described setting step. The support position determination step of determining the support reaction force at each of the plurality of support positions and the plurality of support positions using the finite element method is performed so as to be equal to the reaction force generated at each of the plurality of support positions in the state. You may also have more.
　前記載置工程において、前記複数の支持体の位置が前記素材の中心線に対して左右対称になるように前記素材を載置してもよい。 In the above-described placement step, the material may be placed so that the positions of the plurality of supports are symmetrical with respect to the center line of the material.
　前記製造方法は、前記研磨工程と前記切断工程との間に、保護膜で前記素材を覆う工程をさらに有し、前記切断工程において、前記保護膜で覆われた状態の前記素材における前記切断位置に加圧された水を噴射することにより前記素材を切断してもよい。 The manufacturing method further includes a step of covering the material with a protective film between the polishing step and the cutting step, and in the cutting step, the cutting position of the material covered with the protective film. The material may be cut by injecting pressurized water into the material.
　本発明によれば、ストレスを加えて素材を曲げることなく高精度に面を形成して光学素子を製造することができるという効果を奏する。 According to the present invention, there is an effect that an optical element can be manufactured by forming a surface with high accuracy without applying stress and bending the material.
本実施形態に係る光学素子の製造方法の概要を説明するための図である。It is a figure for demonstrating the outline of the manufacturing method of the optical element which concerns on this embodiment. 光学素子を製造する方法の詳細を説明するための図である。It is a figure for demonstrating the detail of the method of manufacturing an optical element. 光学素子を製造する工程を示すフローチャートである。It is a flowchart which shows the process of manufacturing an optical element. 製造方法を用いて光学素子を製造することによる効果を説明するための図である。It is a figure for demonstrating the effect by manufacturing an optical element by using a manufacturing method.
［光学素子１の製造方法の概要］
　図１は、本実施形態に係る光学素子１の製造方法Ｍの概要を説明するための図である。光学素子１は、例えば、表面が非球面状の非球面光学素子であり、大型望遠鏡で使用される鏡である。製造方法Ｍは、平坦面を有する素材２を研磨することにより、表面が非球面状の光学素子１を製造するための方法である。 [Outline of manufacturing method of optical element 1]
FIG. 1 is a diagram for explaining an outline of the manufacturing method M of the optical element 1 according to the present embodiment. The optical element 1 is, for example, an aspherical optical element having an aspherical surface, and is a mirror used in a large telescope. The manufacturing method M is a method for manufacturing an optical element 1 having an aspherical surface by polishing a material 2 having a flat surface.
　図１に示す素材２は直線状の辺と曲線状の辺を有する板であるが、素材２の形状は任意であり、多角形であってもよく円形であってもよい。素材２の大きさは任意であるが、例えば長い方の幅が１０００ｍｍ以上であり、１０ｍｍから１００ｍｍ程度の厚みを有する。素材２の材質は、例えば、ガラス、セラミックス、樹脂又は金属である。 The material 2 shown in FIG. 1 is a plate having a straight side and a curved side, but the shape of the material 2 is arbitrary and may be polygonal or circular. The size of the material 2 is arbitrary, but for example, the longer width is 1000 mm or more, and the material 2 has a thickness of about 10 mm to 100 mm. The material of the material 2 is, for example, glass, ceramics, resin or metal.
　図１に示すように、製造方法Ｍにおいては、製造する光学素子１よりも大きい素材２を研磨した後に、光学素子１の輪郭線に対応する切断位置Ｃにおいて素材２を切断することにより光学素子１を製造する。切断位置Ｃから素材２の外縁までの距離は、少なくとも研磨に用いる研磨パッドの半径以上である。切断位置Ｃから素材２の外縁までの距離が、研磨パッドの直径以上（すなわち半径の２倍以上）であることがさらに好ましい。研磨パッドの直径は、例えば１００ｍｍである。 As shown in FIG. 1, in the manufacturing method M, the material 2 larger than the optical element 1 to be manufactured is polished, and then the material 2 is cut at the cutting position C corresponding to the contour line of the optical element 1 to obtain the optical element. 1 is manufactured. The distance from the cutting position C to the outer edge of the material 2 is at least equal to or greater than the radius of the polishing pad used for polishing. It is more preferable that the distance from the cutting position C to the outer edge of the material 2 is equal to or larger than the diameter of the polishing pad (that is, twice or more the radius). The diameter of the polishing pad is, for example, 100 mm.
　切断位置Ｃから素材２の外縁までの距離が研磨パッドの半径以上であることにより、切断位置Ｃの周辺位置においても、切断位置Ｃの内側と同等の条件で研磨されるので、光学素子１の全ての領域において十分な研磨精度を確保することができる。切断位置Ｃから素材２の外縁までの距離が研磨パッドの直径以上であることにより、切断位置Ｃの内側と同じ条件で研磨されるので、さらに研磨精度を高めることができる。 Since the distance from the cutting position C to the outer edge of the material 2 is equal to or greater than the radius of the polishing pad, the optical element 1 is polished under the same conditions as the inside of the cutting position C even at the peripheral position of the cutting position C. Sufficient polishing accuracy can be ensured in all areas. When the distance from the cutting position C to the outer edge of the material 2 is equal to or larger than the diameter of the polishing pad, polishing is performed under the same conditions as the inside of the cutting position C, so that the polishing accuracy can be further improved.
［光学素子１の製造方法の詳細説明］
　図２は、光学素子１を製造する方法の詳細を説明するための図である。図３は、光学素子１を製造する工程を示すフローチャートである。図２（ａ）は、研磨中の素材２を研磨する対象の面の側から見た状態を示す模式図である。図２（ｂ）は、研磨中の素材２を側方から見た状態を示す模式図である。図２（ａ）に示すように、切断位置Ｃと外縁との距離の最小値Ｄは、研磨パッド２０の半径Ｒ以上である。
　以下、図２及び図３を参照しながら、光学素子１の製造方法を詳細に説明する。 [Detailed description of manufacturing method of optical element 1]
FIG. 2 is a diagram for explaining details of a method for manufacturing the optical element 1. FIG. 3 is a flowchart showing a process of manufacturing the optical element 1. FIG. 2A is a schematic view showing a state in which the material 2 being polished is viewed from the side of the surface to be polished. FIG. 2B is a schematic view showing a state in which the material 2 being polished is viewed from the side. As shown in FIG. 2A, the minimum value D of the distance between the cutting position C and the outer edge is equal to or greater than the radius R of the polishing pad 20.
Hereinafter, the method for manufacturing the optical element 1 will be described in detail with reference to FIGS. 2 and 3.
　素材２を研磨する際には、光学素子１が望遠鏡に設置された状態に近い状態で素材２を支持しておくことが望ましい。具体的には、図２に示すように、複数の支持体で素材２を支持した状態で素材２を研磨する。具体的には、素材２における切断位置Ｃの内側の領域ｒ１に設けられた複数の内側支持体１１（図２（ａ）においては黒丸で示している）、及び切断位置Ｃの外側の領域ｒ２に設けられた複数の外側支持体１２（図２（ａ）においては白丸で示している）で素材２を支持した状態で素材２を研磨する。図２に示す例においては、領域ｒ１に１０個の内側支持体１１が設けられており、領域ｒ２に１２個の外側支持体１２が設けられている。なお、図２（ｂ）においては、一部の内側支持体１１及び外側支持体１２のみを模式的に示している。 When polishing the material 2, it is desirable to support the material 2 in a state in which the optical element 1 is close to the state in which it is installed in the telescope. Specifically, as shown in FIG. 2, the material 2 is polished while the material 2 is supported by a plurality of supports. Specifically, a plurality of inner supports 11 (indicated by black circles in FIG. 2A) provided in the region r1 inside the cutting position C in the material 2, and the region r2 outside the cutting position C. The material 2 is polished while the material 2 is supported by a plurality of outer supports 12 (indicated by white circles in FIG. 2A) provided in the above. In the example shown in FIG. 2, 10 inner supports 11 are provided in the region r1 and 12 outer supports 12 are provided in the region r2. Note that, in FIG. 2B, only a part of the inner support 11 and the outer support 12 are schematically shown.
　内側支持体１１及び外側支持体１２は弾性を有する物体であり、例えば、ばね、油圧シリンダー、空気シリンダー又は弾性樹脂を有する。内側支持体１１及び外側支持体１２は、支持位置（例えば長さ）と支持反力の大きさとを調整可能な物体であることが好ましい。それぞれの内側支持体１１の弾性力は、複数の内側支持体１１それぞれの支持位置に生じる支持反力が、光学素子１が望遠鏡に設置された状態でそれぞれの支持位置に生じる反力と等しくなるように設計されている。 The inner support 11 and the outer support 12 are elastic objects, and have, for example, a spring, a hydraulic cylinder, an air cylinder, or an elastic resin. The inner support 11 and the outer support 12 are preferably objects whose support position (for example, length) and the magnitude of the support reaction force can be adjusted. The elastic force of each inner support 11 is such that the support reaction force generated at each support position of the plurality of inner supports 11 is equal to the reaction force generated at each support position when the optical element 1 is installed on the telescope. It is designed to be.
　図３に示すように、複数の内側支持体１１が素材２を支持している状態で複数の支持位置それぞれに生じる支持反力が、光学素子１が望遠鏡に設置された状態で複数の支持位置それぞれに生じる反力と等しくなる支持位置及び支持反力を決定するべく、研磨工程を実行する前に支持位置決定工程を実行する（Ｓ１）。支持位置は、例えば素材の重心位置に対する相対位置として表される。 As shown in FIG. 3, the support reaction force generated at each of the plurality of support positions when the plurality of inner supports 11 support the material 2 is generated at the plurality of support positions when the optical element 1 is installed on the telescope. In order to determine the support position and the support reaction force that are equal to the reaction force generated in each, the support position determination step is executed before the polishing step is executed (S1). The support position is represented, for example, as a position relative to the position of the center of gravity of the material.
　支持位置決定工程においては、例えば有限要素法を用いて、複数の支持位置と、複数の支持位置それぞれにおける支持反力（すなわち、内側支持体１１及び外側支持体１２の弾性力）とを決定する。支持位置は、例えば固定した位置を原点として、固定した２点の位置を結ぶ線の方向を基準方向として、原点からの距離及び方向により表される。支持位置は、素材２の重心点からの距離及び方向により表されてもよい。 In the support position determination step, for example, a finite element method is used to determine a plurality of support positions and support reaction forces (that is, elastic forces of the inner support 11 and the outer support 12) at each of the plurality of support positions. .. The support position is represented by the distance and direction from the origin, for example, with the fixed position as the origin and the direction of the line connecting the two fixed positions as the reference direction. The support position may be represented by the distance and direction from the center of gravity of the material 2.
　一例として、まず、領域ｒ１における内側支持体１１の位置を決めた後に、領域ｒ２における外側支持体１２の位置を決定する。複数の外側支持体１２のうち、少なくとも３つは、支持の高さが固定された固定点（図２に示す例における外側支持体１２Ａ、１２Ｂ、１２Ｃ）とする。固定点には、例えば金属のロッドが設けられる。固定点は、素材２におけるできるだけ外縁に近い位置に設けることが好ましい。 As an example, first, the position of the inner support 11 in the region r1 is determined, and then the position of the outer support 12 in the region r2 is determined. Of the plurality of outer supports 12, at least three are fixed points ( outer supports 12A, 12B, 12C in the example shown in FIG. 2) in which the height of the support is fixed. For example, a metal rod is provided at the fixed point. It is preferable that the fixing point is provided at a position as close to the outer edge of the material 2 as possible.
　領域ｒ１における内側支持体１１の位置を決める際には、完成状態の光学素子１（すなわち素材２から切断した後の鏡）を望遠鏡に搭載した時の自重による変形が十分に小さくなるように有限要素法を用いて解析する。内側支持体１１の位置が決まると、有限要素法を用いた解析により、それぞれの内側支持体１１の支持反力が算出される。 When determining the position of the inner support 11 in the region r1, it is finite so that the deformation due to its own weight when the completed optical element 1 (that is, the mirror after cutting from the material 2) is mounted on the telescope is sufficiently small. Analyze using the element method. Once the position of the inner support 11 is determined, the support reaction force of each inner support 11 is calculated by analysis using the finite element method.
　領域ｒ２における外側支持体１２の位置を決める際には、内側支持体１１の支持反力が定められた値になっている状態で領域ｒ１の自重による変形が十分に小さくなるように有限要素法を用いて解析することにより、領域ｒ２に複数の外側支持体１２を追加する。外側支持体１２の位置が決まると、有限要素法を用いた解析により、それぞれの外側支持体１２の支持反力が算出される。 When determining the position of the outer support 12 in the region r2, the finite element method is performed so that the deformation due to the own weight of the region r1 is sufficiently small while the support reaction force of the inner support 11 is at a predetermined value. A plurality of outer supports 12 are added to the region r2 by analysis using. Once the position of the outer support 12 is determined, the support reaction force of each outer support 12 is calculated by analysis using the finite element method.
　支持位置及び支持反力を決定するために、製造しようとする光学素子１と同じ形状の光学素子が望遠鏡に設置された状態で測定された光学素子の複数の位置（以下、複数の測定位置という）における反力の大きさを示す測定データを取得してもよい。この場合、複数の内側支持体１１及び複数の外側支持体１２を用いて素材２を支持した状態において、複数の測定位置における反力の大きさが、取得した測定データが示す値に等しくなるように、複数の内側支持体１１の位置と弾性力、及び複数の外側支持体１２の位置と弾性力を探索する。このようにして決定した弾性力を有する複数の内側支持体１１及び複数の外側支持体１２を準備し、決定した支持位置に複数の内側支持体１１及び複数の外側支持体１２を設置する。 In order to determine the support position and the support reaction force, a plurality of positions (hereinafter referred to as a plurality of measurement positions) of the optical elements measured in a state where the optical elements having the same shape as the optical element 1 to be manufactured are installed in the telescope. ), Measurement data indicating the magnitude of the reaction force may be acquired. In this case, when the material 2 is supported by the plurality of inner supports 11 and the plurality of outer supports 12, the magnitude of the reaction force at the plurality of measurement positions is equal to the value indicated by the acquired measurement data. In addition, the positions and elastic forces of the plurality of inner supports 11 and the positions and elastic forces of the plurality of outer supports 12 are searched for. A plurality of inner supports 11 and a plurality of outer supports 12 having the elastic force determined in this manner are prepared, and the plurality of inner supports 11 and the plurality of outer supports 12 are installed at the determined support positions.
　なお、複数の内側支持体１１を設置する位置は、素材２を切断する前と後とで、複数の内側支持体１１が素材２を支持する複数の位置それぞれに生じる支持反力の変化が相対的に小さくなる位置であることが好ましい。このような位置を特定するために、支持位置決定工程においては、図１（ａ）に示す切断前の状態において複数の内側支持体１１と複数の外側支持体１２とで素材２を支持している間における複数の支持位置それぞれに生じる支持反力と、図１（ｃ）に示す切断後の状態における複数の支持位置それぞれに生じる支持反力とを比較する。 The positions where the plurality of inner supports 11 are installed are before and after the material 2 is cut, and the changes in the supporting reaction forces that occur at each of the plurality of positions where the plurality of inner supports 11 support the material 2 are relative. It is preferable that the position is small. In order to specify such a position, in the support position determination step, the material 2 is supported by the plurality of inner supports 11 and the plurality of outer supports 12 in the state before cutting shown in FIG. 1A. The support reaction force generated at each of the plurality of support positions during the process is compared with the support reaction force generated at each of the plurality of support positions in the state after cutting shown in FIG. 1 (c).
　そして、切断前の支持反力と切断後の支持反力との差が最小になるように、複数の内側支持体１１及び複数の外側支持体１２を設置する位置を決定する。複数の内側支持体１１に対応する複数の支持位置それぞれにおける支持反力の切断前後の差の平均値が最小になるように、複数の内側支持体１１及び複数の外側支持体１２を設置する位置を決定してもよい。 Then, the positions where the plurality of inner supports 11 and the plurality of outer supports 12 are installed are determined so that the difference between the support reaction force before cutting and the support reaction force after cutting is minimized. Positions where the plurality of inner supports 11 and the plurality of outer supports 12 are installed so that the average value of the difference between the support reaction forces before and after cutting at each of the plurality of support positions corresponding to the plurality of inner supports 11 is minimized. May be determined.
　決定した支持位置に複数の内側支持体１１及び複数の外側支持体１２を設置した後に、複数の内側支持体１１及び複数の外側支持体１２で素材２を支持するように素材２を載置する載置工程を実行する（Ｓ２）。この際、複数の内側支持体１１及び複数の外側支持体１２の位置が素材２の中心線に対して左右対称になるように素材２を載置する。このように載置することで、高い精度で予め決定した位置に素材２を載置しやすくなる。 After installing the plurality of inner supports 11 and the plurality of outer supports 12 at the determined support positions, the material 2 is placed so that the material 2 is supported by the plurality of inner supports 11 and the plurality of outer supports 12. The mounting step is executed (S2). At this time, the material 2 is placed so that the positions of the plurality of inner supports 11 and the plurality of outer supports 12 are symmetrical with respect to the center line of the material 2. By placing the material 2 in this way, it becomes easy to place the material 2 at a predetermined position with high accuracy.
　続いて、複数の内側支持体１１及び複数の外側支持体１２で素材２を支持した状態で研磨工程を実行する（Ｓ３）。研磨工程においては、複数の内側支持体１１が素材２を支持している状態で複数の支持位置それぞれに生じる支持反力が、光学素子１が望遠鏡に設置された状態で複数の支持位置それぞれに生じる反力と等しくなるように複数の外側支持体１２が素材２を支持する状態で素材２を研磨する。また、研磨工程においては、素材２を切断する前と後とで、複数の内側支持体１１が素材２を支持する複数の支持位置それぞれに生じる支持反力の変化が相対的に小さくなる位置において複数の外側支持体１２が素材２を支持する状態で素材２を研磨してもよい。 Subsequently, the polishing step is executed with the material 2 supported by the plurality of inner supports 11 and the plurality of outer supports 12 (S3). In the polishing step, the support reaction force generated at each of the plurality of support positions while the plurality of inner supports 11 support the material 2 is applied to each of the plurality of support positions when the optical element 1 is installed on the telescope. The material 2 is polished with the plurality of outer supports 12 supporting the material 2 so as to be equal to the generated reaction force. Further, in the polishing step, at a position where the change in the supporting reaction force generated at each of the plurality of supporting positions where the plurality of inner supports 11 support the material 2 is relatively small before and after cutting the material 2. The material 2 may be polished with the plurality of outer supports 12 supporting the material 2.
　研磨工程においては、研磨パッド２０を回転させながら素材２の全領域にわたって移動させる。研磨パッド２０の半径Ｒは、切断位置Ｃと素材２の外縁との距離の最小値（例えば図２（ａ）に示すＤ）よりも小さい。したがって、研磨パッド２０を素材２の外縁付近にまで移動することで、研磨パッド２０の中心位置が切断位置Ｃの位置に接する状態で研磨することができるので、切断位置Ｃの付近においても切断位置Ｃの内側の領域ｒ１と同等の条件で素材２を研磨することができる。 In the polishing process, the polishing pad 20 is rotated and moved over the entire area of the material 2. The radius R of the polishing pad 20 is smaller than the minimum value of the distance between the cutting position C and the outer edge of the material 2 (for example, D shown in FIG. 2A). Therefore, by moving the polishing pad 20 to the vicinity of the outer edge of the material 2, polishing can be performed in a state where the center position of the polishing pad 20 is in contact with the position of the cutting position C. Therefore, the cutting position can be obtained even in the vicinity of the cutting position C. The material 2 can be polished under the same conditions as the region r1 inside C.
　研磨工程が終了すると、切断位置Ｃで素材２を切断する。必須ではないが、素材２を切断する前に、保護膜で素材２を覆う保護膜形成工程を実行することが好ましい（Ｓ４）。保護膜形成工程においては、例えばフッ素を含む保護剤をスプレーで素材２に塗布することにより、保護膜を形成する。素材２の表面を保護膜で覆うことで、切断工程において生じる粉末により素材２の表面に傷が生じることを予防することができる。 When the polishing process is completed, the material 2 is cut at the cutting position C. Although not essential, it is preferable to carry out a protective film forming step of covering the material 2 with a protective film before cutting the material 2 (S4). In the protective film forming step, for example, a protective film containing fluorine is applied to the material 2 by spraying to form a protective film. By covering the surface of the material 2 with a protective film, it is possible to prevent the surface of the material 2 from being scratched by the powder generated in the cutting step.
　続いて、切断位置Ｃにおいて素材２を切断する切断工程を実行する（Ｓ５）。素材２を切断する方法は任意であるが、素材２に加わるストレスを小さくするために、保護膜で覆われた状態の素材２における切断位置Ｃに加圧された水を噴射することにより素材２を切断するウォータージェット法を用いることが好ましい。 Subsequently, a cutting step of cutting the material 2 at the cutting position C is executed (S5). The method of cutting the material 2 is arbitrary, but in order to reduce the stress applied to the material 2, the material 2 is sprayed with pressurized water at the cutting position C in the material 2 covered with the protective film. It is preferable to use a water jet method for cutting.
［試作結果］
　図４は、製造方法Ｍを用いて光学素子１を製造することによる効果を説明するための図である。図４（ａ）は、製造方法Ｍを用いて製造した光学素子１の外縁付近の平坦度を示す図であり、濃淡が光学素子１の厚みに対応している。濃淡の差が小さいほど平坦度が大きい。 [Prototype result]
FIG. 4 is a diagram for explaining the effect of manufacturing the optical element 1 by using the manufacturing method M. FIG. 4A is a diagram showing the flatness near the outer edge of the optical element 1 manufactured by the manufacturing method M, and the shading corresponds to the thickness of the optical element 1. The smaller the difference in shade, the greater the flatness.
　図４（ｂ）は、製造する光学素子の最終形状と同じ形状の素材を研磨することにより製造した光学素子の外縁付近の平坦度を示す図である。図４（ａ）と図４（ｂ）とを比較すると、図４（ａ）における濃淡の変化は、図４（ｂ）における濃淡の変化よりもはるかに小さく、製造方法Ｍを用いて光学素子１を製造することにより、光学素子１の平坦度が向上していることがわかる。 FIG. 4B is a diagram showing the flatness near the outer edge of the optical element manufactured by polishing a material having the same shape as the final shape of the optical element to be manufactured. Comparing FIG. 4A and FIG. 4B, the change in shading in FIG. 4A is much smaller than the change in shading in FIG. 4B, and the optical element using the manufacturing method M is used. It can be seen that the flatness of the optical element 1 is improved by manufacturing 1.
［製造方法Ｍによる効果］
　以上説明したように、製造方法Ｍにおいては、研磨工程において、研磨パッド２０を用いて、光学素子１の輪郭線に対応する切断位置Ｃよりも少なくとも研磨パッド２０の半径以上外側の位置まで素材２を研磨する。その後、切断位置Ｃで素材２を切断することにより光学素子１を製造する。このようにすることで、切断位置Ｃの付近にも研磨パッド２０の中心付近が接触するので、切断位置Ｃの付近においても切断位置Ｃの内側の領域ｒ１と同等の条件で素材２を研磨することができる。 [Effect of manufacturing method M]
As described above, in the manufacturing method M, in the polishing step, the polishing pad 20 is used to reach a position at least outside the radius of the polishing pad 20 from the cutting position C corresponding to the contour line of the optical element 1. To polish. After that, the optical element 1 is manufactured by cutting the material 2 at the cutting position C. By doing so, the vicinity of the center of the polishing pad 20 also comes into contact with the vicinity of the cutting position C, so that the material 2 is polished under the same conditions as the region r1 inside the cutting position C even in the vicinity of the cutting position C. be able to.
　したがって、製造方法Ｍを用いて光学素子１を製造することにより、素材２にストレスを加えて素材２を曲げることなく、光学素子１の外縁付近における加工精度を向上させることができる。その結果、製造方法Ｍによれば、質が高い光学素子１を低コストで製造することが可能になる。なお、以上の説明においては、非球面を有する光学素子１を製造する場合を例示したが、球面を有する光学素子の製造に製造方法Ｍを適用してもよい。 Therefore, by manufacturing the optical element 1 by using the manufacturing method M, it is possible to improve the processing accuracy in the vicinity of the outer edge of the optical element 1 without applying stress to the material 2 and bending the material 2. As a result, according to the manufacturing method M, it is possible to manufacture the high quality optical element 1 at low cost. In the above description, the case of manufacturing the optical element 1 having an aspherical surface has been illustrated, but the manufacturing method M may be applied to the manufacturing of the optical element having a spherical surface.
　以上、本発明を実施の形態を用いて説明したが、本発明の技術的範囲は上記実施の形態に記載の範囲には限定されず、その要旨の範囲内で種々の変形及び変更が可能である。例えば、装置の全部又は一部は、任意の単位で機能的又は物理的に分散・統合して構成することができる。また、複数の実施の形態の任意の組み合わせによって生じる新たな実施の形態も、本発明の実施の形態に含まれる。組み合わせによって生じる新たな実施の形態の効果は、もとの実施の形態の効果を併せ持つ。 Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments, and various modifications and changes can be made within the scope of the gist. is there. For example, all or part of the device can be functionally or physically distributed / integrated in any unit. Also included in the embodiments of the present invention are new embodiments resulting from any combination of the plurality of embodiments. The effect of the new embodiment produced by the combination has the effect of the original embodiment.
１　光学素子
２　素材
１０　土台
１１　内側支持体
１２　外側支持体
２０　研磨パッド 1 Optical element 2 Material 10 Base 11 Inner support 12 Outer support 20 Polishing pad

Claims (7)

  1. 　光学素子の素材を支持する複数の支持体に前記素材を載置する載置工程と、
    　研磨パッドを用いて、前記光学素子の輪郭線に対応する切断位置よりも少なくとも前記研磨パッドの半径以上外側の位置まで前記素材を研磨する研磨工程と、
    　前記研磨する工程の後に、前記切断位置で前記素材を切断する切断工程と、
    　を有する光学素子の製造方法。     The mounting process of mounting the material on a plurality of supports supporting the material of the optical element, and
    A polishing step of using a polishing pad to polish the material to a position at least outside the radius of the polishing pad from the cutting position corresponding to the contour line of the optical element.
    After the polishing step, a cutting step of cutting the material at the cutting position and
    A method for manufacturing an optical element having.
  2. 　前記載置工程において、前記素材における前記切断位置の内側の領域に設けられた複数の内側支持体、及び前記切断位置の外側の領域に設けられた複数の外側支持体で前記素材を支持するように前記素材を載置する、
    　請求項１に記載の光学素子の製造方法。     In the pre-described step, the material is supported by a plurality of inner supports provided in the region inside the cutting position in the material and a plurality of outer supports provided in the region outside the cutting position. Place the material on the
    The method for manufacturing an optical element according to claim 1.
  3. 　前記研磨工程において、前記切断工程において前記素材を切断する前と後とで、前記複数の内側支持体が前記素材を支持する複数の支持位置それぞれに生じる支持反力の変化が相対的に小さくなる位置において前記複数の外側支持体が前記素材を支持する状態で前記素材を研磨する、
    　請求項２に記載の光学素子の製造方法。     In the polishing step, the change in the support reaction force generated at each of the plurality of support positions where the plurality of inner supports support the material becomes relatively small before and after cutting the material in the cutting step. Polishing the material with the plurality of outer supports supporting the material at the position.
    The method for manufacturing an optical element according to claim 2.
  4. 　前記研磨工程において、前記複数の内側支持体が前記素材を支持している状態で複数の支持位置それぞれに生じる支持反力が、前記光学素子が望遠鏡に設置された状態で前記複数の支持位置それぞれに生じる反力と等しくなるように前記複数の外側支持体が前記素材を支持する状態で前記素材を研磨する、
    　請求項２に記載の光学素子の製造方法。     In the polishing step, the support reaction force generated at each of the plurality of support positions while the plurality of inner supports support the material is generated at each of the plurality of support positions when the optical element is installed on the telescope. The material is polished with the plurality of outer supports supporting the material so as to be equal to the reaction force generated in the above.
    The method for manufacturing an optical element according to claim 2.
  5. 　前記載置工程の前に、前記複数の内側支持体が前記素材を支持している状態で前記複数の支持位置それぞれに生じる支持反力が、前記光学素子が望遠鏡に設置された状態で前記複数の支持位置それぞれに生じる反力と等しくなるように、有限要素法を用いて前記複数の支持位置と、前記複数の支持位置それぞれにおける支持反力を決定する支持位置決定工程をさらに有する、
    　請求項４に記載の光学素子の製造方法。     Prior to the pre-described step, the support reaction force generated at each of the plurality of support positions in a state where the plurality of inner supports support the material is such that the plurality of support reaction forces are generated in a state where the optical element is installed in the telescope. It further has a support position determining step of determining the plurality of support positions and the support reaction force at each of the plurality of support positions by using the finite element method so as to be equal to the reaction force generated at each of the support positions.
    The method for manufacturing an optical element according to claim 4.
  6. 　前記載置工程において、前記複数の支持体の位置が前記素材の中心線に対して左右対称になるように前記素材を載置する、
    　請求項１から５のいずれか一項に記載の光学素子の製造方法。     In the above-described placement step, the material is placed so that the positions of the plurality of supports are symmetrical with respect to the center line of the material.
    The method for manufacturing an optical element according to any one of claims 1 to 5.
  7. 　前記研磨工程と前記切断工程との間に、保護膜で前記素材を覆う工程をさらに有し、
    　前記切断工程において、前記保護膜で覆われた状態の前記素材における前記切断位置に加圧された水を噴射することにより前記素材を切断する、
    　請求項１から６のいずれか一項に記載の光学素子の製造方法。
          A step of covering the material with a protective film is further provided between the polishing step and the cutting step.
    In the cutting step, the material is cut by injecting pressurized water at the cutting position in the material covered with the protective film.
    The method for manufacturing an optical element according to any one of claims 1 to 6.
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH09239653A (en) * 1996-03-06 1997-09-16 Nikon Corp Polishing device
US7118449B1 (en) * 2004-09-20 2006-10-10 Carl Zeiss Smt Ag Method of manufacturing an optical element
JP2009166136A (en) * 2008-01-10 2009-07-30 Nano-Optonics Research Institute Grinding device to manufacture optical element, manufacturing method of optical element and precision measuring device for precisely measuring shape/dimension of metallic mold to manufacture optical element or optical element
JP2019505829A (en) * 2015-12-02 2019-02-28 カール・ツァイス・エスエムティー・ゲーエムベーハー Method for polishing optical surface and optical element

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0266944U (en) * 1988-11-11 1990-05-21

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH09239653A (en) * 1996-03-06 1997-09-16 Nikon Corp Polishing device
US7118449B1 (en) * 2004-09-20 2006-10-10 Carl Zeiss Smt Ag Method of manufacturing an optical element
JP2009166136A (en) * 2008-01-10 2009-07-30 Nano-Optonics Research Institute Grinding device to manufacture optical element, manufacturing method of optical element and precision measuring device for precisely measuring shape/dimension of metallic mold to manufacture optical element or optical element
JP2019505829A (en) * 2015-12-02 2019-02-28 カール・ツァイス・エスエムティー・ゲーエムベーハー Method for polishing optical surface and optical element

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