JP2005219185A - Machining method - Google Patents
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- JP2005219185A JP2005219185A JP2004032190A JP2004032190A JP2005219185A JP 2005219185 A JP2005219185 A JP 2005219185A JP 2004032190 A JP2004032190 A JP 2004032190A JP 2004032190 A JP2004032190 A JP 2004032190A JP 2005219185 A JP2005219185 A JP 2005219185A
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- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2215/00—Press-moulding glass
- C03B2215/40—Product characteristics
- C03B2215/41—Profiled surfaces
- C03B2215/412—Profiled surfaces fine structured, e.g. fresnel lenses, prismatic reflectors, other sharp-edged surface profiles
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Abstract
Description
本発明は、加工方法に関し、特に光学素子の成形用金型を加工するのに好適な加工方法に関する。 The present invention relates to a processing method, and more particularly to a processing method suitable for processing a mold for molding an optical element.
従来より、例えば光ピックアップ装置用の対物レンズなどの高精度光学素子の成形用金型の光学転写面加工には、すくい面のノーズ半径が0.1〜1.5mm程度、頂角が40〜60°程度の単結晶ダイヤモンド製のRバイトが使用されており、それにより光学転写面形状が例えば一般非球面方程式で表現される単一面で構成される場合には、超精密加工機を使用することにより切削加工のみで高精度な光学転写面を得ることが可能である。一方、より微細な形状構造を有する光学転写面を創成加工する際には、特許文献1に記載するように、さらに微細なノーズ半径を有するRバイトが使用されている。
特許文献1に記載する微細なノーズ半径を有するRバイトを用いることで、より精密な光学転写面の創成が可能となった。ところで、近年における光ピックアップ装置の分野では、青紫色レーザなどを用いてより高密度な情報の記録及び/又は再生を行うことが望まれており、これに対して、光ピックアップ装置に用いる光学素子に、少なくとも一方の光学機能面が光軸を中心とした複数の光学機能領域に分割され、該複数の光学機能領域のうちの少なくとも1つが、光軸を中心とした輪帯状の領域に分割され、かつ各輪帯に所定数の不連続な段差が設けられるとともに、当該不連続な段差が設けられた輪帯が連続的に配された回折構造を設けようとする試みがある。しかるに、このような段差のある微細な回折構造を光学素子に形成するためには、その金型の光学面を、100μm以下の幅で輪帯状に深く切削する必要がある。ところが、上述したRバイトでは、縁部が干渉してしまい、そのように狭い幅で輪帯形状を切削することはできない。 By using the R bite having a fine nose radius described in Patent Document 1, a more precise optical transfer surface can be created. By the way, in the field of optical pickup devices in recent years, it is desired to record and / or reproduce information with higher density using a blue-violet laser or the like. Further, at least one of the optical functional surfaces is divided into a plurality of optical functional areas centered on the optical axis, and at least one of the plurality of optical functional areas is divided into a ring-shaped area centered on the optical axis. In addition, there is an attempt to provide a diffraction structure in which a predetermined number of discontinuous steps are provided in each annular zone and the annular zones provided with the discontinuous steps are continuously arranged. However, in order to form such a fine diffractive structure with a step in an optical element, it is necessary to cut the optical surface of the mold deeply in a ring shape with a width of 100 μm or less. However, in the above-described R cutting tool, the edge part interferes, and the annular zone shape cannot be cut with such a narrow width.
本発明は、かかる問題に鑑みてなされたものであり、例えば回折レンズに代表されるような光学素子の成形用金型の加工に好適であり、高精度な加工面を形成できる加工方法を提供することを目的とする。 The present invention has been made in view of such a problem. For example, the present invention is suitable for processing a mold for molding an optical element represented by a diffractive lens, and provides a processing method capable of forming a highly accurate processed surface. The purpose is to do.
請求項1に記載の加工方法は、ダイヤモンドからなる切れ刃のすくい面に、金型の回転軸に対して交差する方向に少なくとも100μm以内の長さで直線状に延在する直線部を含む第1の縁部と、前記第1の縁部より長く且つ前記第1の縁部の端部に接続する直線状の第2の縁部及び第3の縁部とを形成したダイヤモンド工具を用いて、少なくとも一方の光学機能面が光軸を中心とした複数の光学機能領域に分割され、該複数の光学機能領域のうちの少なくとも1つが、光軸を中心とした輪帯状の領域に分割され、かつ各輪帯に所定数の不連続な段差が設けられるとともに、当該不連続な段差が設けられた輪帯が連続的に配された構造である回折構造を有する光学素子を成形するための金型の光学転写面を加工する加工方法であって、
前記金型を回転させながら、その光学転写面に複数段の階段を有する輪帯溝を加工する場合において、前記ダイヤモンド工具の第1の縁部を用いて第1の深さ位置まで前記光学転写面を加工する第1ステップと、更に前記ダイヤモンド工具を前記第1の深さ位置より浅い第2の深さ位置まで前記ダイヤモンド工具を戻す第2ステップと、更に前記ダイヤモンド工具を前記回転軸と交差する方向に移動することで前記光学転写面を加工する第3ステップと、を有し、前記輪帯溝内において、段が深い順に階段を加工することを特徴とする。
The processing method according to claim 1, wherein the rake face of the cutting edge made of diamond includes a linear portion extending linearly with a length of at least 100 μm in a direction intersecting the rotation axis of the mold. Using a diamond tool formed with one edge and a linear second edge and a third edge that are longer than the first edge and connected to the end of the first edge , At least one optical functional surface is divided into a plurality of optical functional areas centered on the optical axis, and at least one of the plurality of optical functional areas is divided into ring-shaped areas centered on the optical axis, In addition, a predetermined number of discontinuous steps are provided in each annular zone, and a gold for molding an optical element having a diffractive structure in which the annular zones provided with the discontinuous steps are continuously arranged. A processing method for processing an optical transfer surface of a mold,
In the case of processing an annular groove having a plurality of steps on the optical transfer surface while rotating the mold, the optical transfer to the first depth position using the first edge of the diamond tool. A first step of machining a surface; a second step of returning the diamond tool to a second depth position shallower than the first depth position; and further intersecting the rotation axis with the diamond tool. And a third step of processing the optical transfer surface by moving in a direction in which the step is processed, and the steps are processed in the descending order of the steps in the annular groove.
本発明について、図面を参照して説明する。図1は、本発明にかかる加工方法に用いると好適なダイヤモンド工具Tの先端のすくい面側から見た図(a)及びその側面図(b)である。図1(a)において、ダイヤモンド工具Tは、直線状に延在する先端の第1の縁部T1(100μm以下)と、第1の縁部T1の両端から直交する方向に直線状に延在する第2の縁部T2と第3の縁部T3とを有し、これらによって方形状のすくい面T5を形成している。第2の縁部T2は、第3の縁部T3から離隔するように延在する第4の縁部T4に接続されている。ここで方形とは、互いに平行に延在する縁部T2,T3のうち短い方の第2の縁部T2における第4の縁部T4側の端部(先端から距離βの位置)から、第1の縁部T1に平行な線T6を引くことで、縁部T1,T2、T3,線T6で囲われる領域をいうものとする。尚、本明細書中、縁部同士が接続するとは、縁部同士が直接接続している場合のほか、他の単一もしくは複数の直線及び/又は円弧を介して間接的に接続している場合も含む。 The present invention will be described with reference to the drawings. FIG. 1 is a view (a) and a side view (b) of a diamond tool T as viewed from the rake face side suitable for use in the machining method according to the present invention. In FIG. 1 (a), the diamond tool T extends linearly in a direction perpendicular to the first edge T1 (100 μm or less) of the tip extending linearly and both ends of the first edge T1. The second edge portion T2 and the third edge portion T3 are formed to form a rectangular rake face T5. The second edge T2 is connected to a fourth edge T4 that extends away from the third edge T3. Here, the square shape refers to the end portion (position of the distance β from the tip) on the fourth edge portion T4 side of the shorter second edge portion T2 of the edge portions T2 and T3 extending in parallel with each other. By drawing a line T6 parallel to one edge T1, a region surrounded by the edges T1, T2, T3 and the line T6 is meant. In this specification, the term “edges are connected to each other” means that the edges are indirectly connected via other single or plural straight lines and / or arcs in addition to the case where the edges are directly connected to each other. Including cases.
図2は、図1のダイヤモンド工具を用いて加工された後の金型Mの斜視図であり、図3は、その光学転写面の概略拡大断面図である。本発明の加工方法によって加工される金型Mは、少なくとも一方の光学機能面が光軸を中心とした複数の光学機能領域に分割され、該複数の光学機能領域のうちの少なくとも1つが、光軸を中心とした輪帯状の領域に分割され、かつ各輪帯に所定数の不連続な段差が設けられるとともに、当該不連続な段差が設けられた輪帯が連続的に配された構造である回折構造を有する光学素子成形に用いられると好適である。かかる回折構造は、断面が階段状になっており、それに相補する形で、図3に示すような金型Mの光学転写面(光学素子の光学面を転写する面をいうが、ニッケル・隣・銅メッキが施されていると好ましい)に輪帯状の溝が、複数段の階段を有して形成されることとなる。尚、図3において、ダイヤモンド工具Tは、X軸方向(回転軸に近づく方向ともいう)及びZ軸方向(金型の回転軸と平行な方向ともいう)に移動可能となっている。 FIG. 2 is a perspective view of the mold M after being processed using the diamond tool of FIG. 1, and FIG. 3 is a schematic enlarged sectional view of the optical transfer surface. The mold M processed by the processing method of the present invention has at least one optical function surface divided into a plurality of optical function areas centered on the optical axis, and at least one of the plurality of optical function areas is a light beam. It is divided into ring-shaped regions centered on the axis, and each ring zone has a predetermined number of discontinuous steps, and the ring zones with the discontinuous steps are continuously arranged. It is suitable for use in molding an optical element having a certain diffractive structure. Such a diffractive structure has a stepped cross section, and is complementary to the optical transfer surface of the mold M as shown in FIG. -It is preferable that the copper plating is applied), and the annular groove is formed with a plurality of steps. In FIG. 3, the diamond tool T is movable in the X-axis direction (also referred to as a direction approaching the rotation axis) and the Z-axis direction (also referred to as a direction parallel to the rotation axis of the mold).
本発明の加工方法の一例を示す。本発明の加工は、段々と深くなる複数段の階段を備えた輪帯状の溝構造(単に溝又は輪帯溝ともいう)を形成する場合に効果的であるが、金型に形成されるべき溝構造の形状は、予め超精密加工機の制御装置にインプットされているものとする。図3に示す例では、光軸Oから外周に向かって、この順序で溝構造G1,G2、G3が光学転写面に形成されるものとするが、溝構造G1,G2は外周に向かうにつれて階段状の段差(階段ともいう)が深くなり、溝構造G3は逆に内周に向かうにつれて階段状の段差が深くなるものとする。尚、ここで「浅い」又は「深い」とは、回転軸の方向において、加工前の金型の表面からダイヤモンド工具を用いて切り込んだ場合における切り込み量により相対的に区別されるものとする。又、「直線部を含む第1の縁部」とは、直線部のみから第1の縁部を構成してもよく、或いは直線部と、その一方の端部もしくは両端に連結した別の直線部もしくは円弧とで、第1の縁部を構成しても良いことを意味する。更に、「切り込み方向」とは、回転軸に平行であって、金型に接近する方向をいうものとする。 An example of the processing method of this invention is shown. The processing according to the present invention is effective when forming a ring-shaped groove structure (simply referred to as a groove or a ring-shaped groove) having a plurality of steps that are gradually deepened, but should be formed in a mold. It is assumed that the shape of the groove structure is input in advance to the control device of the ultraprecision machine. In the example shown in FIG. 3, the groove structures G1, G2, and G3 are formed on the optical transfer surface in this order from the optical axis O toward the outer periphery, but the groove structures G1 and G2 are stepped toward the outer periphery. It is assumed that the stepped step (also referred to as a staircase) becomes deeper and the stepped stepped portion becomes deeper toward the inner periphery of the groove structure G3. Here, “shallow” or “deep” is relatively distinguished by the depth of cut when a diamond tool is used to cut from the surface of the mold before processing in the direction of the rotation axis. In addition, the “first edge including a straight portion” may constitute the first edge only from a straight portion, or another straight line connected to one end or both ends of the straight portion. It means that the first edge may be constituted by a part or an arc. Furthermore, the “cutting direction” is a direction parallel to the rotation axis and approaching the mold.
加工を行うには、まず金型Mを光軸(回転軸ともいう)Oの回りに回転させ、ダイヤモンド工具Tの第1の縁部T1を、金型Mの光学転写面(ここでは上面)に対して押し当てながら光軸Oから外周側に向かって(X軸方向に)移動させ、溝構造G3におけるここでは4段目の段(溝構造G3内で最も深い段)に対応した基準位置(点線の位置であり、溝構造G3の最も内周側の位置)で、光軸Oに対して平行に且つ金型Mに更に押しつける方向(Z軸方向)に第1の位置まで移動させる(第1のステップ)。すると、ダイヤモンド工具Tが金型Mの光学転写面を切削加工し、輪帯状の溝が形成されるが、溝の底面は第1の縁部T1により切削され、溝の側面は第2の縁部T2及び第3の縁部T3により切削される。更にX軸方向の位置を維持しつつ、ダイヤモンド工具Tを加工面から遠ざかる方向に第2の位置まで移動し即ち戻し(第2のステップ)、更にダイヤモンド工具Tを光軸Oから離れる方向に移動させることで溝構造G3の光軸Oから遠い方の側面(内周面)が第2の縁部T2により切削される(第3のステップ)。これを複数回繰り返すことで、複数段の階段を備えた溝構造G3が加工形成される。 In order to perform processing, first, the mold M is rotated around an optical axis (also referred to as a rotation axis) O, and the first edge T1 of the diamond tool T is moved to the optical transfer surface (here, the upper surface) of the mold M. The reference position corresponding to the fourth step (the deepest step in the groove structure G3) in the groove structure G3 here is moved from the optical axis O toward the outer peripheral side (in the X-axis direction) while being pressed against the groove structure G3. (The position of the dotted line, the position on the innermost peripheral side of the groove structure G3) is moved to the first position in the direction further pressed against the mold M (Z-axis direction) in parallel with the optical axis O (Z-axis direction). First step). Then, the diamond tool T cuts the optical transfer surface of the mold M to form a ring-shaped groove, but the bottom surface of the groove is cut by the first edge T1, and the side surface of the groove is the second edge. Cutting is performed by the portion T2 and the third edge T3. Further, while maintaining the position in the X-axis direction, the diamond tool T is moved away from the processing surface to the second position, that is, returned (second step), and the diamond tool T is further moved away from the optical axis O. By doing so, the side surface (inner peripheral surface) farther from the optical axis O of the groove structure G3 is cut by the second edge T2 (third step). By repeating this a plurality of times, the groove structure G3 having a plurality of steps is formed.
一方、次いで溝構造G2を加工する場合には、以下のようにする。ダイヤモンド工具Tを溝構造G2を加工するための基準位置と等しいZ軸方向位置にセットした状態で、光軸Oに近づく方向(X軸方向)に移動させ、溝構造G2におけるここでは4段目の段(溝構造G2内で最も浅い段)に対応した基準位置(実線の位置であり、溝構造G2の最も外周側の位置)で、光軸Oに対して平行に且つ金型Mに押しつける方向(Z軸方向)に第1の位置まで移動させる(第1のステップ)。すると、ダイヤモンド工具Tが金型Mの光学転写面を切削加工し、輪帯状の溝が形成されるが、溝の底面は第1の縁部T1により切削され、溝の側面は第2の縁部T2及び第3の縁部T3により切削される。更にX軸方向の位置を維持しつつ、ダイヤモンド工具Tを加工面から遠ざかる方向に第2の位置まで移動し即ち戻し(第2のステップ)、更にダイヤモンド工具Tを光軸Oに近づける方向に移動させることで溝構造G2の光軸Oに近い方の側面(外周面)が第3の縁部T3により切削される(第3のステップ)。これを複数回繰り返すことで、複数段の階段を備えた溝構造G2が加工形成される。更に、ダイヤモンド工具Tを溝構造G1を加工するための基準位置と等しいZ軸方向位置にセットした状態で、光軸Oに近づく方向(X軸方向)に移動させ、上述と同様にして溝構造G1の加工を行う。その加工後、形成すべき溝がなければ、ダイヤモンド工具Tを光軸に近づく方向に移動させて加工を終了する。溝構造G1〜G3の加工順序にはこだわらず、例えば溝構造G1の加工を最初に行ったり、ランダムに行っても良い。 On the other hand, when the groove structure G2 is subsequently processed, the following is performed. The diamond tool T is moved in the direction approaching the optical axis O (X-axis direction) in a state in which the diamond tool T is set at the Z-axis direction position equal to the reference position for processing the groove structure G2, and the fourth step in the groove structure G2 here. Is pressed against the mold M in parallel with the optical axis O at a reference position corresponding to the step (the shallowest step in the groove structure G2) (the position of the solid line and the outermost periphery of the groove structure G2). Move to the first position in the direction (Z-axis direction) (first step). Then, the diamond tool T cuts the optical transfer surface of the mold M to form a ring-shaped groove, but the bottom surface of the groove is cut by the first edge T1, and the side surface of the groove is the second edge. Cutting is performed by the portion T2 and the third edge T3. Further, while maintaining the position in the X-axis direction, the diamond tool T is moved to the second position in the direction away from the machining surface, that is, returned (second step), and further moved in a direction to bring the diamond tool T closer to the optical axis O. By doing so, the side surface (outer peripheral surface) closer to the optical axis O of the groove structure G2 is cut by the third edge T3 (third step). By repeating this a plurality of times, the groove structure G2 having a plurality of steps is formed. Further, the diamond tool T is moved in the direction approaching the optical axis O (X-axis direction) in a state in which the diamond tool T is set at the Z-axis direction position equal to the reference position for processing the groove structure G1, and the groove structure is the same as described above. G1 is processed. After the machining, if there is no groove to be formed, the diamond tool T is moved in the direction approaching the optical axis, and the machining is finished. Regardless of the processing order of the groove structures G1 to G3, for example, the processing of the groove structure G1 may be performed first or randomly.
ここで、本発明の作用効果を述べると、通常ダイヤモンド工具Tは片持ち状態にあり、しかも細長いすくい面を有するため、切削加工時に側面から大きな力を受けたとき、先端がしなるように変形しやすいという特性を有する。即ち、最も深い溝の側面を、ダイヤモンド工具Tを光軸に交差する方向に移動させて、第2の縁部T2又は第3の縁部T3を用いて切削しようとすると、溝の側面より大きな力を受けて、例えば本来光軸Oと平行にならなければならない側面が傾斜してしまう恐れがある。図8は、本発明者らが行った試験結果の例を示しており、側面が傾斜した溝の断面形状を示す顕微鏡写真である。 Here, the function and effect of the present invention will be described. Since the diamond tool T is normally in a cantilever state and has a long and thin rake face, it is deformed so that the tip is bent when receiving a large force from the side face during cutting. It has the characteristic that it is easy to do. That is, when the side of the deepest groove is moved in a direction intersecting the optical axis with the diamond tool T and an attempt is made to cut using the second edge T2 or the third edge T3, the side is larger than the side of the groove. Under the force, for example, there is a risk that the side surface that should be essentially parallel to the optical axis O is inclined. FIG. 8 shows an example of test results conducted by the present inventors, and is a photomicrograph showing the cross-sectional shape of a groove whose side surface is inclined.
そこで、本発明においては、溝構造G1〜G3のいずれにおいても、段が最も深い位置から加工を行うようにしているので、図4に示すように、その溝構造内で最初に加工される最も深い溝の底面が第1の縁部T1により切削され、且つその側面は第2の縁部T2及び第3の縁部T3により等しい切削抵抗力を受けながら切削されるから、側面が傾斜しない溝構造を精度良く形成でき、精度の良い光学素子を成形できる金型を製造できる。 Therefore, in the present invention, since any of the groove structures G1 to G3 is processed from the deepest position, as shown in FIG. 4, the most processed first in the groove structure. Since the bottom surface of the deep groove is cut by the first edge portion T1, and the side surface thereof is cut while receiving equal cutting resistance force by the second edge portion T2 and the third edge portion T3, the groove in which the side surface is not inclined. A mold capable of forming the structure with high accuracy and molding an optical element with high accuracy can be manufactured.
請求項2に記載の加工方法は、請求項1に記載の発明において、前記第1ステップから第3ステップを複数回繰り返すことにより、前記輪帯溝を形成することを特徴とする。 The processing method according to claim 2 is characterized in that, in the invention according to claim 1, the annular groove is formed by repeating the first step to the third step a plurality of times.
請求項3に記載の加工方法は、請求項1又は2に記載の加工方法において、前記ダイヤモンド工具の第1の縁部の長さは、前記光学素子の前記段部の光軸直交方向の最小幅より小さいことを特徴とする。光学素子に設ける回折構造の種類によっては、段部の光軸直交幅が異なる場合もあるが、その場合、ダイヤモンド工具の第1の縁部T1の長さα(図1(a)参照)を最小幅B(図3参照)より小さくすれば、ダイヤモンド工具Tを光軸に交差する方向に移動させることで全ての回折構造に対応した溝を形成できる。 The processing method according to claim 3 is the processing method according to claim 1 or 2, wherein the length of the first edge portion of the diamond tool is the maximum in the optical axis orthogonal direction of the step portion of the optical element. It is characterized by being smaller than a narrow width. Depending on the type of diffractive structure provided in the optical element, the optical axis orthogonal width of the step portion may be different. In this case, the length α (see FIG. 1A) of the first edge T1 of the diamond tool is set. If the width is smaller than the minimum width B (see FIG. 3), grooves corresponding to all the diffractive structures can be formed by moving the diamond tool T in the direction intersecting the optical axis.
請求項4に記載の加工方法は、ダイヤモンドからなる切れ刃のすくい面に、金型の回転軸に対して交差する方向に少なくとも100μm以内の長さで直線状に延在する直線部を含む第1の縁部と、前記第1の縁部より長く且つ前記第1の縁部の端部に接続する直線状の第2の縁部及び第3の縁部とを形成したダイヤモンド工具を用いて、少なくとも一方の光学機能面が光軸を中心とした複数の光学機能領域に分割され、該複数の光学機能領域のうちの少なくとも1つが、光軸を中心とした輪帯状の領域に分割され、かつ各輪帯に所定数の不連続な段差が設けられるとともに、当該不連続な段差が設けられた輪帯が連続的に配された構造である回折構造を有する光学素子を成形するための金型の光学転写面を加工する加工方法であって、
前記金型の光学転写面に複数段の階段を有する輪帯溝を加工する場合において、前記金型を回転させながら、前記輪帯溝の内周面を再加工するときは、前記ダイヤモンド工具を、形成されている内周面の位置よりも前記回転軸に近い位置で前記輪帯溝内に挿入し、その後前記ダイヤモンド工具を前記回転軸と交差する方向に移動することにとって加工を行い、又は前記輪帯溝の外周面を再加工するときは、前記ダイヤモンド工具を、形成されている外周面の位置よりも前記回転軸から遠い位置で前記輪帯溝内に挿入し、その後前記ダイヤモンド工具を前記回転軸と交差する方向に移動することにとって加工を行うことを特徴とする。
According to a fourth aspect of the present invention, there is provided a processing method including: a straight portion extending linearly with a length of at least 100 μm in a direction intersecting a rotation axis of a mold on a rake face of a cutting edge made of diamond. Using a diamond tool formed with one edge and a linear second edge and a third edge that are longer than the first edge and connected to the end of the first edge , At least one optical functional surface is divided into a plurality of optical functional areas centered on the optical axis, and at least one of the plurality of optical functional areas is divided into ring-shaped areas centered on the optical axis, In addition, a predetermined number of discontinuous steps are provided in each annular zone, and a gold for molding an optical element having a diffractive structure in which the annular zones provided with the discontinuous steps are continuously arranged. A processing method for processing an optical transfer surface of a mold,
In the case of processing an annular groove having a plurality of steps on the optical transfer surface of the mold, when the inner peripheral surface of the annular groove is reworked while rotating the mold, the diamond tool is used. Performing processing for inserting into the annular groove at a position closer to the rotation axis than the position of the formed inner peripheral surface, and then moving the diamond tool in a direction intersecting the rotation axis, or When reworking the outer peripheral surface of the annular groove, the diamond tool is inserted into the annular groove at a position farther from the rotation axis than the position of the formed outer peripheral surface, and then the diamond tool is inserted. Processing is performed for moving in a direction crossing the rotation axis.
本発明について、図面を参照して説明する。図5は、金型の光学転写面の概略拡大断面図である。加工が終了した金型は超精密加工機から取り外されて検査されるが、この際に許容される精度が得られていないことが判明した場合、修正加工が行われることがある。かかる場合、その金型は超精密加工機に再度取り付けられるが、前回加工された位置と完全に同一な位置に取り付けられることはまれである。従って、修正加工を行うために、前回加工されたときのX軸方向位置に基づいて、ダイヤモンド工具を最も深い位置に合わせて溝構造内に挿入しようとしたときに、溝構造の側面と、ダイヤモンド工具とがわずかに交差していると、挿入時にダイヤモンド工具が側面から大きなストレスを受け折損してしまう恐れがある。 The present invention will be described with reference to the drawings. FIG. 5 is a schematic enlarged sectional view of the optical transfer surface of the mold. The mold that has been processed is removed from the ultra-precision processing machine and inspected. However, if it is found that the accuracy that is acceptable at this time is not obtained, correction processing may be performed. In such a case, the mold is reattached to the ultra-precision machine, but is rarely attached to the same position as the previously machined position. Therefore, when trying to insert the diamond tool into the groove structure at the deepest position based on the position in the X-axis at the time of the previous machining in order to perform correction processing, the side surface of the groove structure and the diamond If the tool crosses slightly, the diamond tool may be damaged due to great stress from the side during insertion.
そこで、本発明においては、金型Mを回転させながら、光軸(回転軸)位置の位置は右方である図5において、輪帯溝Gの内周面Giを再加工するときは、ダイヤモンド工具Tを、形成されている内周面Giの位置よりも回転軸に近い位置(ここでは右方)で輪帯溝G内に挿入し、その後ダイヤモンド工具Tを回転軸と交差する方向(ここでは左方)に移動することによって加工を行う(太い矢印参照)ことで、ダイヤモンド工具Tの折損等を回避できる。尚、同様にして、輪帯溝Gの外周面Goを再加工するときは、ダイヤモンド工具Tを、形成されている外周面Goの位置よりも回転軸から遠い位置で輪帯溝G内に挿入し、その後ダイヤモンド工具Tを回転軸と交差する方向に移動することによって加工を行えることはいうまでもない。 Therefore, in the present invention, when the mold M is rotated, the position of the optical axis (rotating axis) is on the right side in FIG. The tool T is inserted into the annular groove G at a position closer to the rotation axis than the position of the formed inner peripheral surface Gi (here, to the right), and then the diamond tool T intersects the rotation axis (here In this case, the diamond tool T can be prevented from being broken by performing the processing by moving it to the left (see the thick arrow). Similarly, when the outer peripheral surface Go of the annular groove G is reworked, the diamond tool T is inserted into the annular groove G at a position farther from the rotation axis than the position of the formed outer peripheral surface Go. Needless to say, machining can be performed by moving the diamond tool T in the direction intersecting the rotation axis.
請求項5に記載の加工方法は、請求項4に記載の発明において、前記ダイヤモンド工具の第1の縁部の長さは、前記光学素子の前記段部の光軸直交方向の最小幅より小さいことを特徴とする。 According to a fifth aspect of the present invention, in the invention according to the fourth aspect, the length of the first edge portion of the diamond tool is smaller than the minimum width in the direction perpendicular to the optical axis of the step portion of the optical element. It is characterized by that.
請求項6に記載の加工方法は、請求項1乃至5のいずれかに記載の発明において、前記金型の光学転写面にニッケル・隣・銅メッキを施していることを特徴とする。特に、ニッケル・隣・銅メッキは被切削性に優れるため、長い工具寿命を確保できるからである。尚、光学転写面に、ニッケル・隣メッキを用いても良く、銅、アルミ、金属ガラス等のコーティングを行っても類似の効果が得られる。 A processing method according to a sixth aspect is characterized in that, in the invention according to any one of the first to fifth aspects, nickel / adjacent / copper plating is applied to the optical transfer surface of the mold. In particular, nickel / neighboring / copper plating is excellent in machinability, so that a long tool life can be secured. Incidentally, nickel / adjacent plating may be used on the optical transfer surface, and a similar effect can be obtained by coating copper, aluminum, metallic glass or the like.
ここで「光学素子」としては、例えばレンズ、プリズム、回折格子光学素子(回折レンズ、回折プリズム、回折板、色収差補正素子)、光学フィルター(空間ローパスフィルター、波長バンドパスフィルター、波長ローパスフィルター、波長ハイパスフィルター等々)、偏光フィルター(検光子、旋光子、偏光分離プリズム等々)、位相フィルター(位相板、ホログラム等々)があげられるが、以上に限られることはない。 Here, as the “optical element”, for example, a lens, a prism, a diffraction grating optical element (diffraction lens, diffraction prism, diffraction plate, chromatic aberration correction element), an optical filter (spatial low-pass filter, wavelength band-pass filter, wavelength low-pass filter, wavelength High pass filters, etc.), polarizing filters (analyzer, optical rotator, polarization separating prism, etc.), and phase filters (phase plates, holograms, etc.), but are not limited thereto.
本発明によれば、例えば回折レンズに代表されるような光学素子の成形用金型の加工に好適であり、高精度な加工面を形成できる加工方法を提供することができる。 ADVANTAGE OF THE INVENTION According to this invention, it is suitable for the process of the metal mold | die for optical elements represented by a diffraction lens, for example, and can provide the processing method which can form a highly accurate processed surface.
以下、図面を参照して本発明の実施の形態について説明する。図6は、請求項1〜6に記載の発明にかかる加工方法を実行するのに好適な実施の形態である2軸超精密加工機10の斜視図であり、図7は、ダイヤモンド工具の斜視図である。図7に示す2軸超精密加工機10において、不図示の制御装置によってX軸方向に駆動されるX軸テーブル2が、台座1上に配置されている。X軸テーブル2上には、ダイヤモンド工具Tが取り付けられている。又、不図示の制御装置によってZ軸方向に駆動されるZ軸テーブル4が、台座1上に配置されている。Z軸テーブル4上には、不図示の制御装置によって回転駆動される主軸(回転軸)5が取り付けられている。主軸5は、加工すべき転写光学面を有する光学素子成形用の金型(図2参照)を取り付け可能となっている。ダイヤモンド工具Tは、その先端にダイヤモンドチップTcを取り付けており、その形状は図1に示すものと同様である。 Embodiments of the present invention will be described below with reference to the drawings. FIG. 6 is a perspective view of a biaxial ultra-precision machine 10 that is a preferred embodiment for carrying out the machining method according to the first to sixth aspects of the present invention, and FIG. 7 is a perspective view of a diamond tool. FIG. In the two-axis ultraprecision machine 10 shown in FIG. 7, an X-axis table 2 that is driven in the X-axis direction by a control device (not shown) is disposed on a pedestal 1. On the X-axis table 2, a diamond tool T is attached. A Z-axis table 4 driven in the Z-axis direction by a control device (not shown) is disposed on the base 1. On the Z-axis table 4, a main shaft (rotating shaft) 5 that is rotationally driven by a control device (not shown) is attached. The main shaft 5 can be attached with an optical element molding die (see FIG. 2) having a transfer optical surface to be processed. The diamond tool T has a diamond tip Tc attached to its tip, and its shape is the same as that shown in FIG.
本実施の形態にかかる加工方法によれば、主軸5やX・Z軸テーブル2,4の剛性が非常に高く、軸制御分解能が100nm以下の超精密加工機を用いて、主軸5にワークであるところの光学素子成形用の金型を取り付け、主軸回転数1000min−1で回転させ、切り込み量1μm、送り0.2mm/minの条件で、ダイヤモンド工具Tにより、切れ刃の切削点が加工中に連続的に移動するようにして、延性モードで切削加工することにより、図3に示すごとき階段状の輪帯を含む回折構造に対応する溝を、金型の光学転写面に創成することができる。 According to the machining method according to the present embodiment, the spindle 5 and the X / Z axis tables 2 and 4 have extremely high rigidity, and an ultra-precision machining machine having an axis control resolution of 100 nm or less is used to work the spindle 5 with a workpiece. A die for forming an optical element is attached, rotated at a spindle rotation speed of 1000 min −1 , and the cutting point of the cutting edge is being processed by the diamond tool T under conditions of a cutting depth of 1 μm and a feed of 0.2 mm / min. The groove corresponding to the diffractive structure including the step-like annular zone as shown in FIG. 3 can be created on the optical transfer surface of the mold by cutting in the ductile mode so that it moves continuously. it can.
以上、本発明を実施の形態を参照して説明してきたが、本発明は上記実施の形態に限定して解釈されるべきではなく、適宜変更・改良が可能であることはもちろんである。例えば、本発明の加工方法は、光学素子の成形用金型の加工以外にも用いることができる。又、本発明の加工方法に用いるダイヤモンド工具は、すくい面の形状が、方形状ではなく、第1の縁部より付け根側が狭幅の先太形状であってもよい。 The present invention has been described above with reference to the embodiments. However, the present invention should not be construed as being limited to the above-described embodiments, and can be modified or improved as appropriate. For example, the processing method of the present invention can be used in addition to processing a molding die for optical elements. Further, in the diamond tool used in the processing method of the present invention, the shape of the rake face may not be a square shape, but may be a tapered shape with a narrower base side than the first edge.
M 金型
T ダイヤモンド工具
10 超精密加工機
M Mold T Diamond tool 10 Ultra-precision machine
Claims (6)
前記金型を回転させながら、その光学転写面に複数段の階段を有する輪帯溝を加工する場合において、前記ダイヤモンド工具の第1の縁部を用いて第1の深さ位置まで前記光学転写面を加工する第1ステップと、更に前記ダイヤモンド工具を前記第1の深さ位置より浅い第2の深さ位置まで前記ダイヤモンド工具を戻す第2ステップと、更に前記ダイヤモンド工具を前記回転軸と交差する方向に移動することで前記光学転写面を加工する第3ステップと、を有し、前記輪帯溝内において、段が深い順に階段を加工することを特徴とする加工方法。 A first edge portion including a straight portion extending linearly at a length of at least 100 μm in a direction intersecting the rotation axis of the mold on the rake face of the cutting edge made of diamond; Using a diamond tool that is longer than the edge and has a linear second edge and a third edge connected to the end of the first edge, at least one of the optical functional surfaces is an optical axis Is divided into a plurality of optical function areas, at least one of the plurality of optical function areas is divided into ring-shaped areas centering on the optical axis, and a predetermined number of discontinuities in each ring zone Processing method for processing an optical transfer surface of a mold for forming an optical element having a diffractive structure in which a step is provided and a ring zone provided with the discontinuous step is continuously arranged Because
In the case of processing an annular groove having a plurality of steps on the optical transfer surface while rotating the mold, the optical transfer to the first depth position using the first edge of the diamond tool. A first step of machining a surface; a second step of returning the diamond tool to a second depth position shallower than the first depth position; and further intersecting the rotation axis with the diamond tool. And a third step of processing the optical transfer surface by moving in a direction to move, and processing the steps in descending order of the steps in the annular groove.
前記金型の光学転写面に複数段の階段を有する輪帯溝を加工する場合において、前記金型を回転させながら、前記輪帯溝の内周面を再加工するときは、前記ダイヤモンド工具を、形成されている内周面の位置よりも前記回転軸に近い位置で前記輪帯溝内に挿入し、その後前記ダイヤモンド工具を前記回転軸と交差する方向に移動することにとって加工を行い、又は前記輪帯溝の外周面を再加工するときは、前記ダイヤモンド工具を、形成されている外周面の位置よりも前記回転軸から遠い位置で前記輪帯溝内に挿入し、その後前記ダイヤモンド工具を前記回転軸と交差する方向に移動することにとって加工を行うことを特徴とする加工方法。 A first edge portion including a straight portion extending linearly at a length of at least 100 μm in a direction intersecting the rotation axis of the mold on the rake face of the cutting edge made of diamond; Using a diamond tool that is longer than the edge and has a linear second edge and a third edge connected to the end of the first edge, at least one of the optical functional surfaces is an optical axis Is divided into a plurality of optical function areas, at least one of the plurality of optical function areas is divided into ring-shaped areas centering on the optical axis, and a predetermined number of discontinuities in each ring zone Processing method for processing an optical transfer surface of a mold for forming an optical element having a diffractive structure in which a step is provided and a ring zone provided with the discontinuous step is continuously arranged Because
In the case of processing an annular groove having a plurality of steps on the optical transfer surface of the mold, when the inner peripheral surface of the annular groove is reworked while rotating the mold, the diamond tool is used. Performing processing for inserting into the annular groove at a position closer to the rotation axis than the position of the formed inner peripheral surface, and then moving the diamond tool in a direction intersecting the rotation axis, or When reworking the outer peripheral surface of the annular groove, the diamond tool is inserted into the annular groove at a position farther from the rotation axis than the position of the formed outer peripheral surface, and then the diamond tool is inserted. A processing method comprising performing processing for moving in a direction intersecting the rotation axis.
6. The processing method according to claim 1, wherein the optical transfer surface of the mold is subjected to nickel / adjacent / copper plating.
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Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2007125649A (en) * | 2005-11-04 | 2007-05-24 | Konica Minolta Opto Inc | Cutting angle adjusting method in machining device, optical element forming metal mold and cutting tool |
WO2008041441A1 (en) | 2006-09-29 | 2008-04-10 | Konica Minolta Opto, Inc. | Metal mold, optical device, metal mold for forming optical device, and process for manufacturing the same |
WO2010103947A1 (en) * | 2009-03-09 | 2010-09-16 | 三星ダイヤモンド工業株式会社 | Grooving tool for thin film solar cell |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH04213421A (en) * | 1990-02-06 | 1992-08-04 | Hughes Aircraft Co | Optical element provided with aspherical double-advancing lattice optical surface |
JPH04281443A (en) * | 1991-03-11 | 1992-10-07 | Hitachi Ltd | Fresnel lens and its manufacture |
JPH06109904A (en) * | 1992-09-28 | 1994-04-22 | Dainippon Printing Co Ltd | Fresnel lens sheet |
JPH1110401A (en) * | 1997-04-21 | 1999-01-19 | Asahi Optical Co Ltd | Working method for zonal lens forming die and cutting tool therefor |
JPH11197902A (en) * | 1997-12-29 | 1999-07-27 | Canon Inc | Manufacture of diffractive surface form |
JP2003145321A (en) * | 2001-11-12 | 2003-05-20 | Allied Material Corp | Monocrystal diamond turning tool |
JP2003275902A (en) * | 2002-03-25 | 2003-09-30 | Sankyo Seiki Mfg Co Ltd | Curved surface cutting method |
-
2004
- 2004-02-09 JP JP2004032190A patent/JP4582495B2/en not_active Expired - Fee Related
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH04213421A (en) * | 1990-02-06 | 1992-08-04 | Hughes Aircraft Co | Optical element provided with aspherical double-advancing lattice optical surface |
JPH04281443A (en) * | 1991-03-11 | 1992-10-07 | Hitachi Ltd | Fresnel lens and its manufacture |
JPH06109904A (en) * | 1992-09-28 | 1994-04-22 | Dainippon Printing Co Ltd | Fresnel lens sheet |
JPH1110401A (en) * | 1997-04-21 | 1999-01-19 | Asahi Optical Co Ltd | Working method for zonal lens forming die and cutting tool therefor |
JPH11197902A (en) * | 1997-12-29 | 1999-07-27 | Canon Inc | Manufacture of diffractive surface form |
JP2003145321A (en) * | 2001-11-12 | 2003-05-20 | Allied Material Corp | Monocrystal diamond turning tool |
JP2003275902A (en) * | 2002-03-25 | 2003-09-30 | Sankyo Seiki Mfg Co Ltd | Curved surface cutting method |
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JP2007125649A (en) * | 2005-11-04 | 2007-05-24 | Konica Minolta Opto Inc | Cutting angle adjusting method in machining device, optical element forming metal mold and cutting tool |
WO2008041441A1 (en) | 2006-09-29 | 2008-04-10 | Konica Minolta Opto, Inc. | Metal mold, optical device, metal mold for forming optical device, and process for manufacturing the same |
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