JP2006185562A - Optical element for optical pickup - Google Patents

Optical element for optical pickup Download PDF

Info

Publication number
JP2006185562A
JP2006185562A JP2004381193A JP2004381193A JP2006185562A JP 2006185562 A JP2006185562 A JP 2006185562A JP 2004381193 A JP2004381193 A JP 2004381193A JP 2004381193 A JP2004381193 A JP 2004381193A JP 2006185562 A JP2006185562 A JP 2006185562A
Authority
JP
Japan
Prior art keywords
diffraction grating
optical element
antireflection structure
pitch
optical
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP2004381193A
Other languages
Japanese (ja)
Inventor
Hiroshi Yamashita
博司 山下
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sanyo Electric Co Ltd
Original Assignee
Sanyo Electric Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sanyo Electric Co Ltd filed Critical Sanyo Electric Co Ltd
Priority to JP2004381193A priority Critical patent/JP2006185562A/en
Publication of JP2006185562A publication Critical patent/JP2006185562A/en
Pending legal-status Critical Current

Links

Images

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical element subjected to surface treatment of stable and low reflectance. <P>SOLUTION: In the optical element provided with a diffraction grating part 2 having a mountain part 21 and a valley part 22, the mountain part 21 and the valley part 22 are formed with a cycle of a micron pitch, reflection preventing structures 23 comprising fine projecting and recessed parts of a submicron pitch are formed on the surface of the mountain part 21 and the valley part 22, and the heights of the projecting and recessed parts of the reflection preventing structures 23 of the mountain part 21 and the valley part 22 which constitute the diffraction grating are different from each other. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

この発明は、光ディスクに情報の記録及び／又は再生を行う光ピックアップ部に用いられる光学部品に関するものであり、特にこれらに用いられる回折格子に関するものである。   The present invention relates to an optical component used in an optical pickup section that records and / or reproduces information on an optical disc, and more particularly to a diffraction grating used in these.

光ピックアップ用の光学部品として、トラッキング制御用にレーザービームを３ビームに分割するために回折格子が使われている。   As an optical component for an optical pickup, a diffraction grating is used to divide a laser beam into three beams for tracking control.

従来より、ガラス、プラスチック等からなる光学素子においては、表面反射による光を減少させるために、反射防止のための表面処理が行われている。その表面処理方法は、光学素子表面上に薄膜の誘電体膜を複数層、真空蒸着等により成膜する方法が行われている。上記した回折格子においても、反射防止のための反射防止コーティングを施し、光の透過率をアップする方法が提案されている（例えば、特許文献１参照）。
特開平８−１２９７７２号公報 Conventionally, in an optical element made of glass, plastic or the like, surface treatment for preventing reflection has been performed in order to reduce light due to surface reflection. As the surface treatment method, a method of forming a plurality of thin dielectric films on the surface of the optical element by vacuum deposition or the like is performed. Also in the diffraction grating described above, a method has been proposed in which an antireflection coating for preventing reflection is applied to increase the light transmittance (see, for example, Patent Document 1).
Japanese Patent Application Laid-Open No. 8-129772

しかしながら、回折格子などの光学素子に反射防止コーティングを施すために、真空蒸着を行った場合、膜厚がばらつき、性能が安定しないという問題がある。更に、基板成型後に、別工程で基板表面に真空蒸着などで反射防止コーティングとしての薄膜を形成しなければならないため、歩留まりが悪く、コストアップの要因になっていた。   However, when vacuum deposition is performed to apply an antireflection coating to an optical element such as a diffraction grating, there is a problem that the film thickness varies and the performance is not stable. Furthermore, after forming the substrate, a thin film as an antireflection coating must be formed on the substrate surface by vacuum deposition or the like in a separate process, resulting in poor yield and increased costs.

また、薄膜形成の場合、分光特性は膜材の物性、特に屈折率に影響される。成膜条件によって屈折率がばらつくという問題もある。更に、薄膜材料も限られており、理想的な分光特性を得ることは難しいという難点があった。   In the case of thin film formation, the spectral characteristics are affected by the physical properties of the film material, particularly the refractive index. There is also a problem that the refractive index varies depending on the film forming conditions. Furthermore, the thin film material is also limited, and it has been difficult to obtain ideal spectral characteristics.

この発明は、上記した従来の問題点に鑑みなされたものにして、安定且つ低反射率の表面処理を施した光学素子を提供することを目的とする。   The present invention has been made in view of the above-described conventional problems, and an object thereof is to provide an optical element that has been subjected to a stable and low-reflectance surface treatment.

この発明は、山部と谷部とを有する回折格子部を備えた光ピックアップ用の光学素子であって、前記山部と谷部はミクロンピッチの周期で形成され、前記山部及び谷部の表面にサブミクロンピッチの微細な凹凸からなる反射防止構造が形成されるとともに、前記回折格子部を構成する山部と谷部とで前記反射防止構造の凹凸の高さが相違するように形成することを特徴とする。   The present invention is an optical element for an optical pickup provided with a diffraction grating portion having a crest and a trough, wherein the crest and trough are formed with a period of a micron pitch, and the crest and trough An antireflection structure consisting of fine irregularities with a submicron pitch is formed on the surface, and the heights of the irregularities of the antireflection structure are different between the peaks and valleys constituting the diffraction grating portion. It is characterized by that.

また、この発明は、ベースとなる回折格子部に段差を有し、前記回折格子部に作製されている前記反射防止構造の凹凸の高さが前記山部と谷部とで差があるように構成することができる。   Further, according to the present invention, the diffraction grating portion serving as a base has a step, and the height of the unevenness of the antireflection structure produced in the diffraction grating portion is different between the peak portion and the valley portion. Can be configured.

さらに、この発明は、谷部の方が山部より反射防止構造の凹凸の高さが高いように構成できる。   Furthermore, this invention can be comprised so that the height of the unevenness | corrugation of an antireflection structure may be higher in a trough part than a peak part.

また、この発明は、ベースとなる回折格子部に段差がなく、前記回折格子部に作製されているサブミクロンピッチの反射防止構造の高さが前記山部と谷部とで相違するように構成できる。   Further, the present invention is configured such that there is no step in the base diffraction grating portion, and the height of the submicron pitch antireflection structure produced in the diffraction grating portion is different between the peak portion and the valley portion. it can.

この発明の光学素子は、回折格子部の表面に反射防止構造が作製されているため、低反射なしかも性能が安定した光学特性が得られる。   In the optical element according to the present invention, since the antireflection structure is formed on the surface of the diffraction grating portion, optical characteristics with low reflection and stable performance can be obtained.

また、この発明により、基板表面に反射防止構造を一体的に形成することで、歩留まりのよい、しかも従来の誘電体薄膜より反射防止効果の高い反射防止機能付き光学素子を提供するこができる。   In addition, according to the present invention, by forming the antireflection structure integrally on the substrate surface, it is possible to provide an optical element with an antireflection function that has a high yield and has an antireflection effect higher than that of a conventional dielectric thin film.

以下、この発明の一実施形態につき図面を参照して説明する。図１は、この発明の光学素子の一実施形態の回折格子を用いた光学記録／再生装置のピックアップ部を光学系を示す構成図である。   Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an optical system of a pickup unit of an optical recording / reproducing apparatus using a diffraction grating according to an embodiment of the optical element of the present invention.

図１に示すように、このピックアップ部の構成は、直線偏光特性を有するレーザー光源１から出射された光をこの発明にかかる回折格子部２を形成した光学素子３と１／４波長板４を通し、レーザー光を３ビームに分割すると共に直線偏光を円偏光に変換する。この実施形態における１／４波長板４は、光透過性板の一方の面には反射防止構造が反対の面には構造複屈折を示す微細構造で構成されている。   As shown in FIG. 1, the structure of this pick-up unit is such that light emitted from a laser light source 1 having linear polarization characteristics includes an optical element 3 and a quarter-wave plate 4 on which a diffraction grating unit 2 according to the present invention is formed. The laser beam is divided into three beams and linearly polarized light is converted into circularly polarized light. The quarter-wave plate 4 in this embodiment is configured with a fine structure that exhibits structural birefringence on one surface of the light-transmitting plate and an antireflection structure on the other surface.

この分割された光は無偏光ビームスプリッタを構成するハーフミラー５によってその反射率に応じた光が対物レンズ６に与えられ、この対物レンズ６でスポット光にして光記録媒体７の記録面に照射される。そして、光記録媒体７で反射した反射光は対物レンズ６、ハーフミラー５を透過し、その透過した光をフォトディテクタ７で受け、フォトディテクタ８から光量に応じた信号が出力される。   The divided light is given to the objective lens 6 by the half mirror 5 constituting the non-polarizing beam splitter, and the light is applied to the objective lens 6 as spot light by the objective lens 6 and irradiated onto the recording surface of the optical recording medium 7. Is done. Then, the reflected light reflected by the optical recording medium 7 is transmitted through the objective lens 6 and the half mirror 5, and the transmitted light is received by the photodetector 7, and a signal corresponding to the amount of light is output from the photodetector 8.

フォトディテクタ８の出力信号は、トラッキング調整信号または読み出しデータとして使用される。   The output signal of the photodetector 8 is used as a tracking adjustment signal or read data.

また、光記録媒体７で反射された反射光のうちハーフミラー５の反射率に応じて、１／４波長板４、光学素子３側へ戻り光が与えられ、光学素子３を経た光がレーザー光源１に帰還する。この戻り光は１／４波長板４により、出射レーザー光に対して偏光面が９０°回転しているため、出射レーザー光とは干渉せず、ノイズの発生は起こらない。   Further, of the reflected light reflected by the optical recording medium 7, returning light is given to the ¼ wavelength plate 4 and the optical element 3 side according to the reflectance of the half mirror 5, and the light passing through the optical element 3 is converted into a laser beam. Return to the light source 1. Since the polarization plane of the return light is rotated by 90 ° with respect to the outgoing laser light by the quarter wavelength plate 4, it does not interfere with the outgoing laser light and no noise is generated.

この発明の特徴とする光学素子３は、回折格子部２の表面に反射防止構造３１が形成されている。図２は、この発明の第１の実施形態にかかる光学素子の回折格子部２の表面に反射防止構造を作製した状態を示す模式的斜視図、図３は、同要部の模式的断面図である。   In the optical element 3 that is a feature of the present invention, an antireflection structure 31 is formed on the surface of the diffraction grating portion 2. FIG. 2 is a schematic perspective view showing a state in which an antireflection structure is produced on the surface of the diffraction grating portion 2 of the optical element according to the first embodiment of the present invention, and FIG. 3 is a schematic cross-sectional view of the main portion. It is.

図２及び図３に示すように、回折格子部２の山部２１と谷部２２の双方にサブミクロンピッチ（ピッチB)の微細な凹凸からなる反射防止構造２３が形成されている。すなわち、図に示すように、回折格子部２の表面全体にはサブミクロンピッチの微細な凹凸からなる反射防止構造２３が形成される。そして、回折格子部２としての山部２１と谷部２２とはミクロンピッチ（ピッチＡ）の周期で形成されている。   As shown in FIGS. 2 and 3, an antireflection structure 23 composed of fine irregularities with a submicron pitch (pitch B) is formed on both the peak portion 21 and the valley portion 22 of the diffraction grating portion 2. That is, as shown in the figure, an antireflection structure 23 made of fine irregularities with a submicron pitch is formed on the entire surface of the diffraction grating portion 2. And the peak part 21 and the trough part 22 as the diffraction grating part 2 are formed with the period of micron pitch (pitch A).

なお、この図２及び図３に示す実施形態は、ベースとなる回折格子部２に段差がある例を示しており、格子の山部２１より谷部２２の反射防止構造２３の方が突起の高さが高く
なっている。谷部２２の反射防止構造２３を高くすることで、ベースとなる回折格子の高さを低く設定することができる。この図２及び図３に示す回折格子部２も基本的には、矩形形状溝の回折格子である。 The embodiment shown in FIGS. 2 and 3 shows an example in which there is a step in the diffraction grating portion 2 serving as a base, and the antireflection structure 23 in the valley portion 22 is more protrusive than the peak portion 21 in the grating. The height is high. By making the antireflection structure 23 of the valley portion 22 high, the height of the diffraction grating serving as the base can be set low. The diffraction grating portion 2 shown in FIGS. 2 and 3 is also basically a diffraction groove having a rectangular groove.

矩形形状溝の回折格子は、図９に示すように、溝深さ（ｈ）とデューティ比ｆ（溝周期（ピッチＡ）に対する溝幅）で回折効率が決まる。溝周期（ピッチＡ）により回折角度が決まる。使用するレーザの波長、回折効率及び分割する３ビームの回折角により、溝深さ、溝周期、デューティ比が決められる。そして、この実施形態のように、表面全体に微細な凹凸からなる反射防止構造２３を設ける場合、上記した溝深さは、光学素子２の屈折率、空気の屈折率と微細な凹凸の深さにより換算された実質的な深さにより決定される。   As shown in FIG. 9, the diffraction efficiency of the diffraction grating having a rectangular groove is determined by the groove depth (h) and the duty ratio f (groove width with respect to the groove period (pitch A)). The diffraction angle is determined by the groove period (pitch A). The groove depth, groove period, and duty ratio are determined by the wavelength of the laser used, the diffraction efficiency, and the diffraction angles of the three beams to be divided. And when providing the antireflection structure 23 which consists of fine unevenness in the whole surface like this embodiment, the above-mentioned groove depth is the refractive index of the optical element 2, the refractive index of air, and the depth of fine unevenness. It is determined by the substantial depth converted by.

反射防止構造２３は、２次元配列構造でも１次元配列構造のどちらでもよいが、反射防止構造２３はのパターンピッチは０次回折格子を構成するようなピッチに設定するのがよい。たとえば、図２に示すように、表面に微細な錐形状の突起が連続して形成された凹凸パターンによる反射防止構造を形成すればよい。この突起のパターン形状は、四角錐形状、六角錐形状、円錐形状など種々の形状が適用できる。パターンピッチ（ピッチＢ）に対するパターン高さの比をアスペクト比とすると、パターンピッチ（ピッチＢ）は使用する光の波長を反射防止構造２３の材料の屈折率で割った値より、小さくすればよく、アスペクト比が１以上であれば高い効果が得られる。よって、回折格子部２の山部２１と谷部２２との高さの差は段差の狙いに応じて適宜選択すればよい。   The antireflection structure 23 may be either a two-dimensional array structure or a one-dimensional array structure, but the pattern pitch of the antireflection structure 23 is preferably set to a pitch that forms a 0th-order diffraction grating. For example, as shown in FIG. 2, an antireflection structure with a concavo-convex pattern in which fine conical projections are continuously formed on the surface may be formed. Various shapes such as a quadrangular pyramid shape, a hexagonal pyramid shape, and a conical shape can be applied to the pattern shape of the protrusions. If the ratio of the pattern height to the pattern pitch (pitch B) is the aspect ratio, the pattern pitch (pitch B) may be smaller than the value obtained by dividing the wavelength of light used by the refractive index of the material of the antireflection structure 23. If the aspect ratio is 1 or more, a high effect can be obtained. Therefore, the height difference between the peak portion 21 and the valley portion 22 of the diffraction grating portion 2 may be appropriately selected according to the aim of the step.

図２、図３に示すような山部２１と谷部２２段差は、通常２００〜４００ｎｍであり、その精度は±１０ｎｍ以下が要求される。また、周期（ピッチＡ）は、２０μｍ〜３０μｍである。上記のように、段差の精度からベースとなる回折格子部の作製もかなり難易度が高いが、この発明では、格子面の前面に反射防止構造２３を作製することで、段差の誤差を補正する効果もある。   2 and 3 is usually 200 to 400 nm, and the accuracy is required to be ± 10 nm or less. The period (pitch A) is 20 μm to 30 μm. As described above, the production of the diffraction grating portion as a base is very difficult due to the accuracy of the step, but in the present invention, the error of the step is corrected by producing the antireflection structure 23 in front of the grating surface. There is also an effect.

図４及び図５は、ベースとなる回折格子部に段差をなくし、反射防止構造のみで回折格子を形成したこの発明の第２の実施形態を示し、図４は、回折格子部２の表面に反射防止構造を作製した状態を示す模式的斜視図、図５は、同要部の模式的断面図である。図４及び図５に示すように、この実施形態は、回折格子部２の山部２１に当たる部分の凹凸からなる反射防止構造２３の突起部分を谷２２の突起より高くしている。高い突起からなる山部２１と低い突起からなる谷部２２とのピッチＡが回折格子部２の溝周期となり、各突起のピッチＢが反射防止構造２３のピッチＢとなる。この実施形態では、ピッチＢは２００〜４００ｎｍである。   4 and 5 show a second embodiment of the present invention in which a step is not formed in the base diffraction grating portion and the diffraction grating is formed only by the antireflection structure, and FIG. 4 shows the surface of the diffraction grating portion 2. FIG. 5 is a schematic cross-sectional view of the main part, showing a state in which the antireflection structure is manufactured. As shown in FIG. 4 and FIG. 5, in this embodiment, the protrusion portion of the antireflection structure 23 formed by the unevenness of the portion corresponding to the peak portion 21 of the diffraction grating portion 2 is made higher than the protrusion of the valley 22. The pitch A between the peak portion 21 made of a high protrusion and the valley portion 22 made of a low protrusion becomes the groove period of the diffraction grating portion 2, and the pitch B of each protrusion becomes the pitch B of the antireflection structure 23. In this embodiment, the pitch B is 200 to 400 nm.

なお、図４及び図５に示す反射防止構造２３は、１次元配列構造となっているが、図２及び図３に示すような２次元配列構造にすることもできる。   Although the antireflection structure 23 shown in FIGS. 4 and 5 has a one-dimensional array structure, a two-dimensional array structure as shown in FIGS. 2 and 3 may be used.

図６は、この発明の第３の実施形態にかかる回折格子部の表面に反射防止構造を作製した状態を示す模式的断面図である。この第３の実施形態は、回折格子部２の山部２１に当たる部分を反射防止構造２３のパターンで構成したものである。   FIG. 6 is a schematic sectional view showing a state in which an antireflection structure is produced on the surface of the diffraction grating portion according to the third embodiment of the present invention. In the third embodiment, a portion corresponding to the peak portion 21 of the diffraction grating portion 2 is configured by a pattern of the antireflection structure 23.

図７は、この発明の第４の実施形態にかかる回折格子部の表面に反射防止構造を作製した状態を示す模式的断面図である。この第４の実施形態は、第３の実施形態とは逆に回折格子部２の谷部２２に当たる部分を反射防止構造２３のパターンで構成したものである。   FIG. 7 is a schematic cross-sectional view showing a state in which an antireflection structure is produced on the surface of the diffraction grating portion according to the fourth embodiment of the present invention. In the fourth embodiment, the portion corresponding to the valley portion 22 of the diffraction grating portion 2 is configured by the pattern of the antireflection structure 23, contrary to the third embodiment.

図６及び図７に示す第３又は第４の実施形態の場合、谷部２２又は山部２１が鏡面部になるため、この鏡面部がある分反射防止効果は、第１又は第２の実施形態に比べ落ちるが、作製が比較的容易であるという利点がある。   In the case of the third or fourth embodiment shown in FIGS. 6 and 7, since the valley portion 22 or the mountain portion 21 becomes a mirror surface portion, the antireflection effect corresponding to the presence of this mirror surface portion is the first or second embodiment. Although it falls compared with a form, there exists an advantage that preparation is comparatively easy.

次に、この発明にかかる反射防止構造を有した光学素子の作製方法の一例につき、図８に従い説明する。図８は、この発明にかかる反射防止構造を有した光学素子の作製方法を工程別に示す模式的断面図である。この図８に示す例は第１の実施形態にかかる光学素子の製造方法である。   Next, an example of a method for producing an optical element having an antireflection structure according to the present invention will be described with reference to FIG. FIG. 8 is a schematic cross-sectional view showing a method of manufacturing an optical element having an antireflection structure according to the present invention, by process. The example shown in FIG. 8 is a method for manufacturing an optical element according to the first embodiment.

まず、図８（ａ）で示すように、ベースとなる谷部２２、山部２１を有する回折格子部２を作製する。続いて、図８（ｂ）に示すように、この回折格子部２の表面にレジスト２１をスピンコートする。   First, as shown in FIG. 8A, a diffraction grating portion 2 having a trough portion 22 and a crest portion 21 as a base is manufactured. Subsequently, as shown in FIG. 8B, a resist 21 is spin-coated on the surface of the diffraction grating portion 2.

その後、図８（ｃ）に示すように、ＥＢ露光、もしくはレーザー干渉露光を行った後、現像し、所定のパターン３１を作製する。   Thereafter, as shown in FIG. 8C, EB exposure or laser interference exposure is performed, followed by development to produce a predetermined pattern 31.

次に、図８（ｄ）に示すように、所定のパターン３１が形成されたレジストをマスクとして、エッチングを行い、ナノ構造の反射防止構造２３を作製する。   Next, as shown in FIG. 8D, etching is performed using the resist on which the predetermined pattern 31 is formed as a mask, and the nano-structure antireflection structure 23 is manufactured.

なお、上記の例では、（ｄ）の工程で、レジストマスクを使いエッチングを行っているが、レジストマスク上にクロム（Ｃｒ）等を蒸着し、リフトオフ工程を経て、Ｃｒマスクでエッチングを行ってもよい。   In the above example, etching is performed using a resist mask in the step (d). However, chromium (Cr) or the like is vapor-deposited on the resist mask, and after a lift-off step, etching is performed with the Cr mask. Also good.

また、図６、図７に示すような構造は、回折格子を作製する工程で使用するフォトマスクを使い露光を行えば、鏡面部が作製できる。   In the structure shown in FIGS. 6 and 7, a mirror surface portion can be manufactured by performing exposure using a photomask used in the process of manufacturing a diffraction grating.

この発明の光学素子の一実施形態の回折格子を用いた光学記録／再生装置のピックアップ部を光学系を示す構成図である。It is a block diagram which shows an optical system for the pick-up part of the optical recording / reproducing apparatus using the diffraction grating of one Embodiment of the optical element of this invention. この発明の第１の実施形態にかかる光学素子の回折格子部の表面に反射防止構造を作製した状態を示す模式的斜視図である。It is a typical perspective view which shows the state which produced the reflection preventing structure in the surface of the diffraction grating part of the optical element concerning 1st Embodiment of this invention. この発明の第１の実施形態にかかる光学素子の要部の模式的断面図である。It is a typical sectional view of an important section of an optical element concerning a 1st embodiment of this invention. この発明の第２の実施形態にかかる光学素子の回折格子部の表面に反射防止構造を作製した状態を示す模式的斜視図である。It is a typical perspective view which shows the state which produced the reflection preventing structure in the surface of the diffraction grating part of the optical element concerning the 2nd Embodiment of this invention. この発明の第２の実施形態にかかる光学素子の要部の模式的断面図である。It is a typical sectional view of an important section of an optical element concerning a 2nd embodiment of this invention. この発明の第３の実施形態にかかる光学素子の模式的断面図である。It is a typical sectional view of the optical element concerning a 3rd embodiment of this invention. この発明の第４の実施形態にかかる光学素子の模式的断面図である。It is a typical sectional view of the optical element concerning a 4th embodiment of this invention. この発明にかかる反射防止構造を有した光学素子の作製方法を工程別に示す模式的断面図である。It is typical sectional drawing which shows the preparation methods of the optical element which has the reflection preventing structure concerning this invention according to process. 矩形溝で構成された回折格子を示す断面図である。It is sectional drawing which shows the diffraction grating comprised by the rectangular groove.

符号の説明Explanation of symbols

２ 回折格子部
３ 光学素子
２１ 山部
２２ 谷部
２３ 反射防止構造 2 Diffraction grating part 3 Optical element 21 Mountain part 22 Valley part 23 Antireflection structure

Claims (4)

山部と谷部とを有する回折格子部を備えた光ピックアップ用の光学素子であって、前記山部と谷部はミクロンピッチの周期で形成され、前記山部及び谷部の表面にサブミクロンピッチの微細な凹凸からなる反射防止構造が形成されるとともに、前記回折格子部を構成する山部と谷部とで前記反射防止構造の凹凸の高さが相違することを特徴とする光ピックアップ用の光学素子。 An optical element for an optical pickup having a diffraction grating portion having a crest and a trough, wherein the crest and trough are formed with a period of micron pitch, and the surface of the crest and trough is submicron. An antireflection structure composed of fine irregularities with a pitch is formed, and the height of the irregularities of the antireflection structure is different between a peak portion and a valley portion constituting the diffraction grating portion. Optical elements. ベースとなる回折格子部に段差を有し、前記回折格子部に作製されている前記反射防止構造の凹凸の高さが前記山部と谷部とで差があることを特徴とする請求項１に記載の光ピックアップ用光学素子。 2. The diffraction grating portion serving as a base has a step, and the height of the unevenness of the antireflection structure manufactured in the diffraction grating portion is different between the peak portion and the valley portion. An optical element for optical pickup as described in 1. 谷部の方が山部より反射防止構造の凹凸の高さが高いことを特徴とする請求項２に記載の光ピックアップ用光学素子。 3. The optical element for an optical pickup according to claim 2, wherein the height of the unevenness of the antireflection structure is higher in the valley portion than in the mountain portion. ベースとなる回折格子部に段差がなく、前記回折格子部に作製されているサブミクロンピッチの反射防止構造の高さが前記山部と谷部とで相違することを特徴とする請求項１に記載の光ピックアップ用光学素子。 2. The height of a submicron pitch antireflection structure produced in the diffraction grating portion is different between the peak portion and the valley portion. The optical element for optical pickup as described.
JP2004381193A 2004-12-28 2004-12-28 Optical element for optical pickup Pending JP2006185562A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2004381193A JP2006185562A (en) 2004-12-28 2004-12-28 Optical element for optical pickup

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2004381193A JP2006185562A (en) 2004-12-28 2004-12-28 Optical element for optical pickup

Publications (1)

Publication Number Publication Date
JP2006185562A true JP2006185562A (en) 2006-07-13

Family

ID=36738544

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2004381193A Pending JP2006185562A (en) 2004-12-28 2004-12-28 Optical element for optical pickup

Country Status (1)

Country Link
JP (1) JP2006185562A (en)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007142186A1 (en) * 2006-06-06 2007-12-13 Panasonic Corporation Optical member
JP2009034630A (en) * 2007-08-03 2009-02-19 Oji Paper Co Ltd Method of manufacturing mono-particle membrane on non-flat surface, method of manufacturing fine structure using mono-particle membrane etching mask, and fine structure formed by the method
JP2009134287A (en) * 2007-11-06 2009-06-18 Seiko Epson Corp Diffraction optical element, method of manufacturing the same and laser machining method
JP2009175707A (en) * 2007-12-27 2009-08-06 Seiko Epson Corp Method of producing fine structure
JP2010152411A (en) * 2010-04-05 2010-07-08 Sony Corp Optical element and its manufacturing method, and replicate substrate for manufacturing optical element and its manufacturing method
JP2011221444A (en) * 2010-04-14 2011-11-04 Ricoh Opt Ind Co Ltd Optical attenuator and optical attenuator module
CN102360092A (en) * 2007-06-19 2012-02-22 阿尔卑斯电气株式会社 Optical element and method for manufacturing the same
JP2012078831A (en) * 2011-09-29 2012-04-19 Oji Paper Co Ltd Manufacturing method of single-particle film on non-planar surface, manufacturing method of microstructure using single-particle film etching mask, and microstructure acquired by manufacturing method
US8665688B2 (en) 2007-01-18 2014-03-04 Sony Corporation Optical device, method of manufacturing the same, replica substrate for producing optical device, and method of producing the same
JP2014071286A (en) * 2012-09-28 2014-04-21 Toppan Printing Co Ltd Optical element
JP2014239223A (en) * 2014-06-09 2014-12-18 王子ホールディングス株式会社 Substrate with single particle film etching mask

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007142186A1 (en) * 2006-06-06 2007-12-13 Panasonic Corporation Optical member
JP5014339B2 (en) * 2006-06-06 2012-08-29 パナソニック株式会社 Optical member
US8665688B2 (en) 2007-01-18 2014-03-04 Sony Corporation Optical device, method of manufacturing the same, replica substrate for producing optical device, and method of producing the same
CN102360092A (en) * 2007-06-19 2012-02-22 阿尔卑斯电气株式会社 Optical element and method for manufacturing the same
JP2009034630A (en) * 2007-08-03 2009-02-19 Oji Paper Co Ltd Method of manufacturing mono-particle membrane on non-flat surface, method of manufacturing fine structure using mono-particle membrane etching mask, and fine structure formed by the method
JP2013210680A (en) * 2007-11-06 2013-10-10 Seiko Epson Corp Diffraction optical element, method of manufacturing the same, and laser machining method
JP2009134287A (en) * 2007-11-06 2009-06-18 Seiko Epson Corp Diffraction optical element, method of manufacturing the same and laser machining method
JP2009175707A (en) * 2007-12-27 2009-08-06 Seiko Epson Corp Method of producing fine structure
JP2010152411A (en) * 2010-04-05 2010-07-08 Sony Corp Optical element and its manufacturing method, and replicate substrate for manufacturing optical element and its manufacturing method
JP2011221444A (en) * 2010-04-14 2011-11-04 Ricoh Opt Ind Co Ltd Optical attenuator and optical attenuator module
JP2012078831A (en) * 2011-09-29 2012-04-19 Oji Paper Co Ltd Manufacturing method of single-particle film on non-planar surface, manufacturing method of microstructure using single-particle film etching mask, and microstructure acquired by manufacturing method
JP2014071286A (en) * 2012-09-28 2014-04-21 Toppan Printing Co Ltd Optical element
JP2014239223A (en) * 2014-06-09 2014-12-18 王子ホールディングス株式会社 Substrate with single particle film etching mask

Similar Documents

Publication Publication Date Title
KR100283502B1 (en) Optical head apparatus
JP3077156B2 (en) Optical element and optical pickup device using the same
EP1640752A1 (en) Multi-level and gray-level diffraction gratings
JPH07182687A (en) Optical pick-up
JP2006185562A (en) Optical element for optical pickup
JPH09198702A (en) Optical pickup device
WO2010016559A1 (en) Diffraction grating, aberration correction element and optical head device
JP2007515667A (en) Holographic data storage medium with structured surface
JP2008257771A (en) Optical pickup
JP5562152B2 (en) Diffraction grating
KR20090064444A (en) Diffraction element and optical head device equipped therewith
JP2007234094A (en) Diffraction grating body, optical head device using the same and manufacturing method of diffraction grating body
JP2800156B2 (en) Optical head device
JP2011187139A (en) Grating element and method for manufacturing the same, and optical pickup device using the grating element
JP3382600B2 (en) Polarizing beam splitter
JP2007334975A (en) Diffraction grating, its manufacturing method, and optical pickup device
JP4338558B2 (en) Optical pickup
US6844044B2 (en) Optical recording medium
US7160652B2 (en) Hologram element
JP2004240297A (en) Optical polarizing beam splitter
JPS63107589A (en) Optical recording medium
JP2004145064A (en) Method for manufacturing diffraction optical element, diffraction optical element, optical system, and optical pickup device
US7929398B2 (en) Optical pickup and optical data processing device using the same
JP2006209891A (en) Optical element for optical pickup
JP2004077806A (en) Phase plate optical element