JPS58133645A - Information reader for optical recording medium - Google Patents
Information reader for optical recording mediumInfo
- Publication number
- JPS58133645A JPS58133645A JP57015542A JP1554282A JPS58133645A JP S58133645 A JPS58133645 A JP S58133645A JP 57015542 A JP57015542 A JP 57015542A JP 1554282 A JP1554282 A JP 1554282A JP S58133645 A JPS58133645 A JP S58133645A
- Authority
- JP
- Japan
- Prior art keywords
- light
- beam splitter
- luminous flux
- lens
- 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
Links
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
Landscapes
- Optical Head (AREA)
Abstract
Description
【発明の詳細な説明】
本発明は、光学的記録担体に１鎌されている情報を読み
出すための情報続出装置に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an information output device for reading information stored on an optical record carrier.
第１ａｍａ従来のとの種再生装置の光学系の概念図であ
る。まずこの図に基き、従来装置の構成、光学的記録担
体からの情報読出原理および欠点をａ勇する。直−偏光
レーザ光源（例えは波長６３３亀ｍ ＯＨ・−Ｎ・レー
ザ）１はＰ伽光状ｍｌ（この図の鳩合紘紙画を基準とし
て４ａ光状園を１義する）の細い平行光束（通常ｏ、ｓ
ｓｗφｉｉ！ｌ：）を発し、この平行光束は透過１１−
折格子２を通って三本の光束に分ゆられ丸竹拡大レンズ
３によｊｌｌＰｌに一度焦点を結ぶ。ＰＩからは発歓光
東となシ、偏光ビームスプリツメ４、四分の一波長板５
．可動ミラー６を経由して対物レンズ７に入射し、この
レンズによシ光学的記録担体８の情報記録面上に鼻び焦
点Ｐ２を結ぶ。FIG. 1 is a conceptual diagram of an optical system of a conventional seed regenerating device. First, based on this figure, the configuration of the conventional device, the principle of reading information from an optical record carrier, and the shortcomings will be explained. Directly polarized laser light source (for example, OH・-N・laser with a wavelength of 633 m) 1 is a thin parallel beam of P kojo ml (4a kojoen is defined based on the Hatoai Hiroshi paper painting in this figure). Luminous flux (usually o, s
swφii! l:), and this parallel light beam is transmitted through 11-
The light beam passes through the folded grating 2 and is split into three beams, which are focused once on jllPl by the round bamboo magnifying lens 3. From the PI, Tonanashi Hikaru Higashi, polarizing beam splitter 4, and quarter wave plate 5
．． The light enters the objective lens 7 via the movable mirror 6, and focuses the nose point P2 on the information recording surface of the optical record carrier 8 through this lens.
四分の一波長板５は、直１ｓ−光状態で入射する光束を
円−元状態の光束に変換する機能およびその逆の機能を
持つものであり、また偏光ビームスプリッタ４ｔｉＰ偏
光状態のＩＬＩｍ偏光光束は、透過９させ、Ｓ偏光状謹
め直紐偏光光束をその反射面４Ｒで反射屈折させる機能
を持つ。The quarter-wave plate 5 has the function of converting a light beam incident in the normal 1s-optical state into a circular-element state light beam, and vice versa, and the polarizing beam splitter 5 converts the incident light beam in the 1s-optical state into a circular-element state light beam, and the polarizing beam splitter 5 converts the ILIm polarized light in the 4tiP polarization state. The light beam has the function of transmitting 9 and causing the S-polarized linearly polarized light beam to be reflected and refracted by the reflecting surface 4R.
しかして光学的記録担体８の情報記録面上に焦点を結ん
だ光束は、そこで反射さｌれ再び対物レンｘ７ｓ 可動
ミラー６を経由して四分の一波長板５に至るが、記録担
体８上での反射の際光束ＫＦ１にだけの位＠変化が生じ
ているため、四分の一波長板５を通って１録担体８に向
う円偏光状態の光束と、記録担体８から四分の一波長板
５に戻る光束とでは、円偏光の回転方向が逆と・なって
いる。したがって四分の一波長板５を梅透過し゛て偏光
ビームスシリツタ４に入る光束ｔＩｉＳ偏光状態の直線
偏九光東となり、このためこの反射光は該ビームスプリ
ッタ４の反射面４Ｒで入射光とは直交する方向に反射屈
折されて収束レンズ９に入射し、受光素子１０で電気信
号に変換される。The light beam focused on the information recording surface of the optical record carrier 8 is reflected there and reaches the quarter-wave plate 5 via the objective lens x7s and the movable mirror 6. Since the light flux KF1 undergoes a change in magnitude during reflection at the top, the circularly polarized light flux passes through the quarter-wave plate 5 toward the first record carrier 8, and the quarter-wave light flux from the record carrier 8 The direction of rotation of the circularly polarized light is opposite to that of the light beam returning to the one-wavelength plate 5. Therefore, the light beam passes through the quarter-wave plate 5 and enters the polarizing beam splitter 4 as a linearly polarized light beam with a polarization state of tIiS. Therefore, this reflected light is combined with the incident light at the reflective surface 4R of the beam splitter 4. is reflected and refracted in orthogonal directions, enters the converging lens 9, and is converted into an electrical signal by the light receiving element 10.
７［：学的記録担体８の情報記録面上には、第２−に模
式的に示すように情報記録ビット１１の配列と−いう形
で情報が記録されており、このビット１１０反射率は地
の部分のそれとは異なるように形成さ−れそいる。この
ため情報記録面上に焦点を結ぶ光・ スボツ） １２
（１３，１４）が該ピッ”ト１１上に照射される場合と
そうでない場合とでは、受光素子１０の受光部１ｓ（１
６，１７）の電気出力に差が生じ、これＫよ〕情報信号
の識別が行なわれる。7 [: Information is recorded on the information recording surface of the scientific record carrier 8 in the form of an arrangement of information recording bits 11 as schematically shown in 2nd-, and the reflectance of this bit 110 is It tends to be formed differently from that of the earth. Therefore, the light that is focused on the information recording surface (substrate) 12
(13, 14) is irradiated onto the pit 11 and when it is not, the light receiving portion 1s (1
6 and 17), and the information signal (K) is identified.
上記情報記録ビット１１は、現在のところ１．６ｐｍと
いう非常に高密度な配列間隔ｐで記憶されている。この
ため情報記録面上に焦点を結ぶ光スポットは直径１μｍ
＠度に絞如込むことが必要であシ。The information recording bits 11 are currently stored at a very high density arrangement interval p of 1.6 pm. Therefore, the light spot focused on the information recording surface has a diameter of 1 μm.
@ It is necessary to narrow down the details.
またその光スポットが情報記録ビット１１の配列を正し
く追跡することが必要である。対物レンズ７は光スポッ
トを小さく絞゛り込むために開口数Ｎ、ム。It is also necessary for the light spot to correctly track the arrangement of the information recording bits 11. The objective lens 7 has a numerical aperture of N, in order to narrow down the light spot to a small size.
が０．５前後の明るい高性能レンズとし、また焦点ずれ
を起さないように光学的記録担体８との間隔を一定に保
つべく駆動可能にする必要がある。この両要求を満足す
るため一般に対物レンズ１は焦点距離が１０■以下の短
焦点レンズが用いられている。It is necessary to use a bright, high-performance lens with an angle of about 0.5, and to be able to drive it so as to maintain a constant distance from the optical record carrier 8 to avoid defocusing. In order to satisfy both of these requirements, the objective lens 1 is generally a short focal length lens with a focal length of 10 mm or less.
他力上記透過型回折格子２と可動ミラー６とは、情報記
録ビット１１の配列を正しく光スポットが追跡するよう
にするトラッキング手段である。。、透過型回折格子２
ｔｉ、例えばｊＩ４図に示すよう一党の透過面２Ｔと不
透過面２０とをピッチｄで規則正しく格子状に配−列し
九もので、これに垂直に平行光束が入射すると、回折、
現象によシθ＝ ａｊｉ” （ｍλ／ｄ）（ｍ−υ、±
１．±２．・・・・・・）の方向に光は回折する。λは
光の波長である。このうちｒｍ ＝ ０に対応する０俗
光を情報信号検出用光スポットとして利用し、ｍ＝±Ｉ
Ｋ対応する＋１次光および一１次光をトラッキング信号
の検出手段−として用いる。The above-mentioned transmission type diffraction grating 2 and movable mirror 6 are tracking means that allow the light spot to correctly track the arrangement of the information recording bits 11. . , transmission type diffraction grating 2
ti, for example, as shown in Figure jI4, there are nine transmissive surfaces 2T and non-transmissive surfaces 20 arranged regularly in a lattice shape with a pitch d, and when a parallel beam of light is incident perpendicularly thereto, diffraction,
According to the phenomenon, θ = aji” (mλ/d) (m−υ, ±
1. ±2. ...) Light is diffracted in the direction. λ is the wavelength of light. Of these, the 0 ordinary light corresponding to rm = 0 is used as a light spot for information signal detection, and m = ±I
The +1st-order light and the 11st-order light corresponding to K are used as tracking signal detection means.
すなわちこの＋１次光の光スボツ）１２．１３を、第２
図に示すように、記録担体８上で情報記録ビット１１の
配列に対して微小角度ａだ、け傾斜して結像するようｔ
（セツティングすると、情報信号ｆ：ｖｔみ出すθ次元
のスポット１２が情報記録ビット１１の配列に対して横
ずれ（第２図Ａ−Ａ方向）を起した場合には、＋１次光
の光スポット、１３と一１次光の光スポット１４０反射
率間に差が生じ、この九め纂３図に示す＋１次光の受光
部１６と一１次光の受光ｓ１７の電気出力信号に差異が
生じる。、つまシトラッキングの誤差が検出できること
となり、このトラッキングの誤差信号に基いて可動ミラ
ー６を駆動すれに、正しいトラッキングを行なわせるこ
とができる。In other words, this +1st-order light light slot) 12.13 is
As shown in the figure, the image is formed on the record carrier 8 at a slight angle a with respect to the arrangement of the information recording bits 11.
(When setting, if the θ-dimensional spot 12 protruding from the information signal f:vt causes a lateral shift (in the A-A direction in Fig. 2) with respect to the arrangement of the information recording bits 11, the +1st-order light spot 12 , 13 and the reflectance of the light spot 140 of the 11th-order light, and a difference occurs in the electrical output signals of the +1st-order light receiving section 16 and the 11th-order light receiving section s17 shown in Figure 3 of this summary. ., it is possible to detect the error in tracking, and by driving the movable mirror 6 based on this tracking error signal, correct tracking can be performed.
しかるに以上に説明し九従来の情報続出装置は、対物レ
ンズ１を中心に考えると、いわゆる有限縮小の結像関係
、つま多焦点Ｐ１およびＰ２に向って光−径を縮少する
関係にあるために、次のような種々の欠点がある。However, as explained above, in the conventional information output device, when considering the objective lens 1 as the center, there is a so-called finite reduction imaging relationship, in which the light diameter decreases toward the multifocal points P1 and P2. However, there are various drawbacks as follows.
１）焦点Ｐ１とＰ２の距離が固定されてしまうので、全
体の、系の大きさを自由にコントロールするεとができ
ない。すなわち装置の小皺化が図シ難い。1) Since the distance between the focal points P1 and P2 is fixed, it is not possible to freely control the size of the entire system. In other words, it is difficult to visualize the appearance of wrinkles in the device.
２）トラツキ、ング補正のために可動ミラー６が回動し
たとき、焦点Ｐ１とＰ２の距離が変化する危険性が大き
く、記録担体８上でのＰ２のずれ、つまり焦点ずれの生
じる可能性が高い。2) When the movable mirror 6 rotates for tracking correction, there is a great risk that the distance between the focal points P1 and P2 will change, and there is a possibility that a shift of P2 on the record carrier 8, that is, a focus shift will occur. expensive.
３）−九ビームスプリツタ４および四分の一波長板５は
、垂直に入射する元以外の光に対しては奉賀的にその光
学的性能が劣化する。すなわちこれらの素子４．５は最
も性能の−よい状態では一使用されていない。3) The optical performance of the nine-beam splitter 4 and the quarter-wave plate 5 deteriorates in response to vertically incident light other than the original light. In other words, these elements 4.5 are unused in their best performance state.
４）透過型回折格子２、偏光ビーム不プリッタ４および
四分の一波長板５を透過する光束径が小さいので、これ
らの光学素子に小、さな異物あるいは欠陥がめった場合
にもその影響度が大きい。4) Since the diameter of the light beam that passes through the transmission diffraction grating 2, polarizing beam splitter 4, and quarter-wave plate 5 is small, even if small foreign objects or defects rarely occur in these optical elements, their influence will be reduced. is large.
５） 回折格子−２に−よる±１次光の回折角度を太き
くしなけれはならないため、格子ピンチｄを小さくしな
ければならず、その製造が困難である。5) Since the diffraction angle of the ±1st-order light by the diffraction grating 2 must be widened, the grating pinch d must be made small, which makes manufacturing difficult.
本発明は、このような従来装置の欠点を解消することを
目的になされたもので、以上の欠点は結局対物レンズか
らみて有限縮少の光学系によ）情報の読み出しを行なう
点に原因があるとの解析に基き、直線偏光レーザ光の、
光源と偏光ビームスプリッタとの間に、該レーザ光を拡
径して平行光線とする光束径拡大レンズを位置させたこ
とを特徴としている。The present invention was made for the purpose of eliminating the drawbacks of the conventional device, and the above drawbacks are ultimately caused by the fact that information is read out using an optical system that is finitely reduced when viewed from the objective lens. Based on the analysis that there is a linearly polarized laser beam,
It is characterized in that a beam diameter enlarging lens is positioned between the light source and the polarizing beam splitter to enlarge the diameter of the laser beam and make it a parallel beam.
本発＠によれば光束径拡大レンズから対物レンズに至る
光束、および対物レンズから偏光ビームスグリツＪＫ戻
る光束は、すべて拡径された平行光束となるため上述の
欠点は解消され、また透過型回折格子は光束径拡大レン
ズと偏光ビームスプリッタ関Ｏ拡径平行光線中に設置す
ることができるので格子ピッチは粗い奄のですむ。According to the present invention, the light flux from the beam diameter expanding lens to the objective lens, and the light flux returning from the objective lens to the polarized beam Suguritsu JK, all become parallel light beams with enlarged diameters, so the above-mentioned drawbacks are eliminated, and the transmission type diffraction grating Since the beam diameter enlarging lens and the polarizing beam splitter can be installed in the enlarged parallel beam, the grating pitch can be coarse.
・図示実施例について詳述すると、第５図は本発明情報
続出装置の光学系の概念図であって、＃！１図の従来装
置との差異は、拡大レンズ３に代えて、光源１からの細
い平行光束を拡径して再び平行光束とする光束径拡大レ
ンズ１８を用い死点、およびこの光束径拡大レンズ１８
の俵側、つまシ拡大された平行光束中に透過型回折格子
２を配置した点の二点である。光束径拡大レンズ１８は
最低前後二群のレンズ系によ、って構成できる。この他
の構成要素は第１図の従来装置と同一であるので、同−
要素には同一の符号を付して説明を省略する。 ゛上
記構成の情報読出装置は、光源１から出る細い平行光束
の直線偏光レーザ光が直ちに回折されることはなく、ま
ず光束径拡大レンズ１８によシ拡径されｈび平行光束と
された後、透過型回折格子２よひロエ動ミラー６を介し
て対物レンズＴに入射し、対物レンズ７は光学的記録担
体８の情報記録面上ＶＣ焦点Ｐ２を結ぶ。該記録面から
の反射光は、位相を反転して栴び対物レンズ７に入シ、
そこで再び半何光束とされた後、可動ミラー６および四
分の一波長板５を経由して偏光ビームスプリッタ４に入
り、反射１１４Ｒで反射屈折されて収束レンズ９により
受光素子１０に入射する。- To explain the illustrated embodiment in detail, FIG. 5 is a conceptual diagram of the optical system of the information outputting device of the present invention, and #! The difference from the conventional device shown in FIG. 18
There are two points on the bale side, where the transmission type diffraction grating 2 is placed in the collimated beam that has been expanded. The beam diameter enlarging lens 18 can be constructed by a lens system of at least two groups, front and rear. Since the other components are the same as the conventional device shown in FIG.
Elements are given the same reference numerals and explanations are omitted.゛In the information reading device configured as described above, the linearly polarized laser beam in the form of a thin parallel beam emitted from the light source 1 is not immediately diffracted, but is first expanded in diameter by the beam diameter enlarging lens 18 and then turned into a parallel beam. , passes through the transmission diffraction grating 2 and the Loe movable mirror 6 into the objective lens T, and the objective lens 7 focuses the VC on the information recording surface of the optical record carrier 8 P2. The reflected light from the recording surface is inverted in phase and enters the objective lens 7.
After being made into a half beam again, the beam enters the polarizing beam splitter 4 via the movable mirror 6 and the quarter-wave plate 5, is reflected and refracted by the reflection 114R, and enters the light receiving element 10 through the converging lens 9.
以上の光線の経路は、光束径拡大レンズ１８と対物レン
ズ１間のｊｔ、ｌｌＡが平行光束である点を除けば、第
１図の従来装置と同一であシ、同一の動作原塩により光
学的配録担体８に記録された情報が読み出される。また
回折格子２による０次光およびｔ１次光ｒｃより、可動
ミ２−６を介してのトラッキング禰正が行なわれる。The path of the above light rays is the same as that of the conventional device shown in FIG. 1, except that jt and llA between the beam diameter enlarging lens 18 and the objective lens 1 are parallel beams. The information recorded on the target recording carrier 8 is read out. Further, tracking correction is performed using the 0th-order light and the t1-order light rc from the diffraction grating 2 via the movable mirror 2-6.
しかして第２図に示す０次回折光スポット１２と±１次
回折光スボツ）１３．１４との間隔は２０〜４０ｐｒｍ
が最適とされている。“第１図の従来装置では焦点ＰＩ
とＰ２は通常２０ ： ｌ’ｌ！度の有限縮小系を形成
しておプ、この場合焦点Ｐ１における０次光スポツトと
±１次光スポットとの間隔は４００〜８００ＦＤＩ程度
離れていることが必要となる。この間隔を得るためには
、拡大レンズ３の焦点距離を仮に１０１ｍとすると、透
過型回折格子２による±１次光の回折角を２．３″〜４
．６°とする必要がある。レーザ光の波長を６３３八に
としてこれを前述の式θ＝ｓｉｉ’（ｍλ／ｄ）（ｍ＝
ｏ、±１．・・・・・・）にあてはめると、従来装置に
おける透過型回折格子２のピッチｄは１６〜８μｍとす
る必要がある。これに対し本発明装置では、対物レンズ
７の焦点距離を１０ｆｉと仮定すると、±１次光の回折
角は０．１〜０．２で足り、したがって透過型回折格子
２のピッチｄは３６０〜１８０μｍでよいことになる。Therefore, the interval between the 0th-order diffracted light spot 12 and the ±1st-order diffracted light spots 13.14 shown in FIG. 2 is 20 to 40 prm.
is considered optimal. “In the conventional device shown in Fig. 1, the focal point PI
and P2 is usually 20: l'l! In this case, the distance between the 0th-order light spot and the ±1st-order light spot at the focal point P1 must be about 400 to 800 FDI. In order to obtain this distance, assuming that the focal length of the magnifying lens 3 is 101 m, the diffraction angle of the ±1st order light by the transmission type diffraction grating 2 must be 2.3" to 4.
．． It needs to be 6°. Assuming that the wavelength of the laser beam is 6338, this is converted into the above formula θ=sii'(mλ/d)(m=
o, ±1. ...), the pitch d of the transmission type diffraction grating 2 in the conventional device needs to be 16 to 8 μm. On the other hand, in the apparatus of the present invention, assuming that the focal length of the objective lens 7 is 10fi, the diffraction angle of the ±1st-order light is sufficient to be 0.1 to 0.2, and therefore the pitch d of the transmission type diffraction grating 2 is 360 to 360. This means that 180 μm is sufficient.
このように本発明装置によれば、透過型回折格子のピッ
チを粗くすることができるためその製造が容易であル、
また光束径拡大レンズ１８と対物しンズ１間の光束は平
行光束となるため前述の欠点はすべてｐｓ消されるので
ある１、
−すなわちＡＩＩ＆後に本発明装置の効果を列挙すると
次の通りである。As described above, according to the device of the present invention, the pitch of the transmission type diffraction grating can be made coarse, so that it is easy to manufacture.
In addition, since the beam between the beam diameter enlarging lens 18 and the objective lens 1 becomes a parallel beam, all of the above-mentioned drawbacks are eliminated.
１） Ｍ過型回折格子２以後の各光学素子の配置が自
由になシ、装態全体の小屋化が図れる。1) The arrangement of each optical element after the M-type diffraction grating 2 can be freely arranged, and the entire device can be made into a shed.
２） ｉ’Ｊ動ミラーがどの様に回動じても焦点Ｐ１
とＰ２の距離が変化しない（本発明装置では焦点Ｐ１は
常に無限遠に６るとみなすことができる）ので。2) No matter how the i'J moving mirror rotates, the focus is P1.
Since the distance between and P2 does not change (in the device of the present invention, the focal point P1 can always be regarded as 6 at infinity).
紀婦担体上での焦点ずれは生じない。No out-of-focus occurs on the carrier.
３）四分の一波長板は原理的に平行光束（ＩＩ直に入射
する光）に対してしかその本来の性能を発揮できないが
、その本来の性能を引出すむとができるので、１＊報信
号の再生特性を向上させることができる
４）偏光ビームスプリッタ４は原理的には平行光束（垂
直に入射する光）に対して最高の特性を発揮するもので
あり、従来装置のような発散光束に対する偏光ビームス
プリッタを製作するのは困離かつ＾価である。し九がっ
て安価なスプリッタを鍛適の状態で使用して情＠信号の
再生特性を向上させることができる。3) In principle, a quarter-wave plate can only demonstrate its original performance for parallel light beams (light directly incident on II), but since it is possible to bring out its original performance, it is possible to 4) In principle, the polarizing beam splitter 4 exhibits the best characteristics for parallel light beams (light that enters perpendicularly), and it can improve the reproduction characteristics for divergent light beams like conventional devices. Manufacturing a polarizing beam splitter is difficult and expensive. Therefore, the reproduction characteristics of the information signal can be improved by using an inexpensive splitter in a suitable condition.
５）ａ過ｉｌＩｉｇｌ折格子、偏光ビームスプリッタお
よび四分の一波長板を通過する光束径は拡大され友もの
となるため、これらの光学素子に偶発的に発生する微小
欠陥の影響を小さくすることができる。5) The diameter of the beam passing through the optical grating, polarizing beam splitter, and quarter-wave plate is enlarged and becomes more uniform, so the influence of minute defects that occur accidentally in these optical elements is reduced. I can do it.
６）透過型回折格子の回折角が小さくてすむので、回折
格子のピッチを大きくすることができ、よって回折格子
を容易かつ安価Ｋｍ造することができる。6) Since the diffraction angle of the transmission type diffraction grating can be small, the pitch of the diffraction grating can be increased, and therefore the diffraction grating can be easily and inexpensively manufactured.
第１図は従来の光学・的記録担体の情報読出装置の光学
系の概念図、第２図は元字的紀録担体上の情報記録ピッ
トおよびこれらに照射される光スポットの状態を模式的
に示す平面図、第３図は三本の光束の受光素子上におけ
る結像位置関係を模式的に示す平面図、第４図は透過Ｗ
−回折格子拡大平面図、第５図は本発明に係る光学的記
録担体の情報読出装置の実施例を示す光学系の概念図で
ある。
１・・・直線偏光レーザ光源、２・・・透過ｍ回折格子
。
４・・・偏光ビームスプリッタ、５・・・四分の一波長
板、６・・・可動ミラー、７・・・対物レンズ、８・・
・光学的記録担体、１０・・・受光素子、１８・・・光
束後拡大レンズ。
４Ｉ絆出願人 旭光学工業株式金社
代理人 弁理士 三 浦 邦 夫
手続補正書（自発）
昭和５８年 ４月３０日
↑長官 若杉和夫殿
事件の表示
昭和５７年特許願第１５５４２号
光学前記Ｍ担体の情報読出装置
代表者 松 本 徹
および発明の詳細な説明の欄
６、補正の内容
（１）特許請求の範囲を別紙の通り補正する。
波長板５は、両者、″！＠声線傷線偏光レーザ光するビ
ームスプリッタを１４１！虞するものであるが、光学原
理上は、単一のハーフミラ−もまた直線偏光レーザ光に
対するビームスプリッタとして用いることができること
が知られている。」と挿入する。
（３）回書第７頁下から第４行ないし第３行、第８頁第
２行ないし第３行、および同頁第一５行ないし第６行に
それぞれ「偏光ビームスプリッタ」とあるのを、「ビー
ムスプリッタ」と補正する。
（４）同書第１１頁第２行の「解消されるの、である、
」の後に、［なお前述のように、光学原理上は、単一の
ハーフミラ−も、偏光ビームスプリッタ４と四分の一波
長板５−ｂ：ら構成したビームスプリッタに換えて用い
うる。」と挿入する。
（５）回書同頁第１１行の「四分の一波長板は」板と偏
光ビームスプリッタの組み合わせを用いた場合、」と挿
入する。
（６）同書同頁第１６行の「偏光ビームスプリッ°り４
は」の前に、「ビームスプリッタとして四分の一波長板
と偏光ビームスプリッタの組み合わせを用いた場合、」
と挿入する。
補正後の特許請求の範囲を記載した書面（特願昭５７−
１５５４２号）
（１）直線偏光レーザ光を、透過型回折格子工ど二Ａ
Ｘ ｆ ＋、にノ、可動ミラーおよび対物レンズを介し
て光学的記録担体に照射し、該記録担体からの反射光を
再び上記対物レンズ よびＵラーＬ血工１」」口仁二り
五ｊユ二ノに導き、このく。
Ａ 、（ｊりユノで入射光とは異る方向に屈折される上
記反射光により上記気宇的記録担体に記録されている情
報を読み出す光学的記録担体の情報読出装置において、
上記直線偏光レーザ光の光源とご二ｈｘｉニー）との間
に、該レーザ光を拡径して平行光線とする光束径拡大レ
ンズを位置させたことを特徴とする光学的記録担体１の
情報読出装置。
（２、特許請求の範囲第１項において、透過型回折格子
は光束径拡大レンズとビームスプリ・ との間に配置さ
れている光学的記録担体の情報読出装置。Figure 1 is a conceptual diagram of the optical system of a conventional information reading device for an optical record carrier, and Figure 2 is a schematic diagram of the information recording pits on the original record carrier and the state of the light spot irradiated onto them. 3 is a plan view schematically showing the image formation positional relationship of three light beams on the light receiving element, and FIG. 4 is a plan view showing the transmission W.
- An enlarged plan view of a diffraction grating. FIG. 5 is a conceptual diagram of an optical system showing an embodiment of an information reading device for an optical record carrier according to the present invention. 1...Linearly polarized laser light source, 2...Transmission m-diffraction grating. 4... Polarizing beam splitter, 5... Quarter wavelength plate, 6... Movable mirror, 7... Objective lens, 8...
- Optical record carrier, 10... Light receiving element, 18... Luminous flux rear magnifying lens. 4I Bond Applicant Asahi Optical Industry Co., Ltd. Agent Patent Attorney Kunio Miura Procedural Amendment (voluntary) April 30, 1981 Carrier Information Reading Device Representative Toru Matsumoto and Detailed Description of the Invention Column 6, Contents of Amendment (1) The scope of the claims will be amended as shown in the attached sheet. The wave plate 5 is used as a beam splitter for the polarized laser beam, but in terms of optical principles, a single half mirror can also be used as a beam splitter for the linearly polarized laser beam. It is known that it can be used." (3) "Polarizing beam splitter" is written in the 4th to 3rd lines from the bottom of page 7 of the circular, the 2nd to 3rd lines of page 8, and the 5th to 6th lines of the same page, respectively. is corrected as a "beam splitter". (4) In the same book, page 11, line 2, “It will be resolved.”
'', then [As mentioned above, in terms of optical principles, a single half mirror can be used in place of the beam splitter composed of the polarizing beam splitter 4 and the quarter-wave plate 5-b. ” is inserted. (5) In the 11th line of the same page of the circular, insert "a quarter-wave plate" when a combination of a plate and a polarizing beam splitter is used. (6) “Polarized beam splitting 4” in line 16 on the same page of the same book.
``When a combination of a quarter-wave plate and a polarizing beam splitter is used as a beam splitter,''
Insert. Document stating the amended scope of patent claims (Japanese Patent Application 1982-
(No. 15542) (1) Linearly polarized laser light is transmitted through a transmission type diffraction grating
X f +, the optical record carrier is irradiated via the movable mirror and the objective lens, and the reflected light from the record carrier is reflected back to the objective lens and the objective lens. Lead to Yujino, Kokoku. A. (In an information reading device for an optical record carrier that reads information recorded on the optical record carrier by the reflected light that is refracted in a direction different from the incident light by the beam,
Information on an optical record carrier 1 characterized in that a beam diameter enlarging lens for expanding the diameter of the laser beam and making it a parallel beam is positioned between the light source of the linearly polarized laser beam and the laser beam. Reading device. (2. Claim 1, wherein the transmission type diffraction grating is arranged between a beam diameter enlarging lens and a beam splitter.
Claims (1)
光ビームスプリッタ、四分の一波長板、可動ミラーおよ
び対物レンズを介して光学的記録担体に照射し、該配録
担体からの反射光を再び上記対物レンズ、可動ミラーお
よび四分の一波長板を介して上記−光ビームスプリッタ
に導き、この偏光ビームスプリッタで入射光とは異なる
方向ＫＪＩ折される上記反射光によ如上記光学的紀録担
体に記録されている情報を読み出す光学的記録担体の情
報続出装置において、上記直線−光レーザ党の光源と１
１１１光ビームスプリツタとの間に、該レーず光を拡任
して平行光線とする光束径拡大レンズを位置させたこと
を特徴とする光学的記録担体の情報続出装置。 （２、特許請求の範囲第１項において、透過型回折格子
は光束径拡大レンズと偏光ビームスプリッタとの関に配
置されている光学的記録担体の情報続出装置。[Claims] 11) Irradiating a linearly polarized laser beam onto an optical record carrier through a transmission 11 diffraction grating, a polarizing beam splitter, a quarter-wave plate, a movable mirror and an objective lens; The reflected light is guided again to the optical beam splitter through the objective lens, movable mirror, and quarter-wave plate, and the reflected light is refracted by the polarization beam splitter in a direction different from that of the incident light. In the information output device for an optical record carrier for reading information recorded on the optical record carrier, the light source of the linear optical laser beam and one
11. An information output device for an optical record carrier, characterized in that a beam diameter enlarging lens for expanding the laser beam into a parallel beam is positioned between the laser beam splitter and the optical beam splitter. (2. Claim 1, wherein the transmission type diffraction grating is disposed between the beam diameter enlarging lens and the polarizing beam splitter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57015542A JPS58133645A (en) | 1982-02-04 | 1982-02-04 | Information reader for optical recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57015542A JPS58133645A (en) | 1982-02-04 | 1982-02-04 | Information reader for optical recording medium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS58133645A true JPS58133645A (en) | 1983-08-09 |
Family
ID=11891675
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP57015542A Pending JPS58133645A (en) | 1982-02-04 | 1982-02-04 | Information reader for optical recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS58133645A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2022141711A (en) * | 2019-07-01 | 2022-09-29 | 大日本印刷株式会社 | Diffusion member, laminate, set of diffusion members, led backlight, and display device |
-
1982
- 1982-02-04 JP JP57015542A patent/JPS58133645A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2022141711A (en) * | 2019-07-01 | 2022-09-29 | 大日本印刷株式会社 | Diffusion member, laminate, set of diffusion members, led backlight, and display device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6728034B1 (en) | Diffractive optical element that polarizes light and an optical pickup using the same | |
| JPS6227456B2 (en) | ||
| JP2001059905A (en) | Diffraction type optical element and optical pickup using this diffraction type optical element | |
| JP2002109778A (en) | Optical pickup device | |
| JPS58133645A (en) | Information reader for optical recording medium | |
| JPS6123575B2 (en) | ||
| JP2716792B2 (en) | Optical information recording / reproducing device | |
| JPS63191328A (en) | Optical head device | |
| TW200403649A (en) | Optical head and optical disk drive | |
| JPH0449535A (en) | Optical reader | |
| JPH0829124A (en) | Displacement measuring device and optical pickup | |
| JP2857245B2 (en) | Optical pickup device | |
| JP3401288B2 (en) | Light detection unit | |
| JP3477928B2 (en) | Optical pickup head device | |
| JP2005025897A (en) | Optical pickup device | |
| US5532477A (en) | Optical pickup apparatus having lens group for determining paths of an incident beam and a reflected & beam | |
| JPH0750032A (en) | Optical head device and optical information device | |
| JP3320826B2 (en) | Optical information recording / reproducing device | |
| KR100272086B1 (en) | Beam adjusted type dual focus optical pickup device | |
| JP3578152B2 (en) | Tracking error signal detection method, optical head device, and optical information device | |
| JPH0120498B2 (en) | ||
| JPH0981955A (en) | Optical pickup | |
| KR19980086185A (en) | Dual Focus Optical Pickup | |
| JPS5994254A (en) | Optical information reader | |
| JPH04311830A (en) | Optical pick-up device |