JPS63205826A - Optical reproducing device - Google Patents
Optical reproducing deviceInfo
- Publication number
- JPS63205826A JPS63205826A JP62038556A JP3855687A JPS63205826A JP S63205826 A JPS63205826 A JP S63205826A JP 62038556 A JP62038556 A JP 62038556A JP 3855687 A JP3855687 A JP 3855687A JP S63205826 A JPS63205826 A JP S63205826A
- Authority
- JP
- Japan
- Prior art keywords
- light
- photodetector
- receiving surface
- optical
- emitted
- 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.)
- Granted
Links
- 230000003287 optical effect Effects 0.000 title claims abstract description 35
- 238000001514 detection method Methods 0.000 claims description 18
- 230000002238 attenuated effect Effects 0.000 abstract description 5
- 230000000694 effects Effects 0.000 description 6
- 230000008929 regeneration Effects 0.000 description 4
- 238000011069 regeneration method Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 201000009310 astigmatism Diseases 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000002411 adverse Effects 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
Landscapes
- Optical Head (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
この発明は情報記録押体に記録されている情報を光学的
に再生する光学的再生装置に関するものであり、特にそ
の再生信号の信号対雑音比を向上させる手段に関するも
のである。[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an optical reproducing device that optically reproduces information recorded on an information recording body, and particularly relates to a signal-to-noise ratio of the reproduced signal. It relates to means for improving the ratio.
第４図は従来の光学的再生装置を示す概略図であり、第
５図はその部分拡大図である。図において、（１）は再
生するための光ビームを発生する半導体レーザなどの発
光源、（２）は発光源（１）から出射された発散光束を
平行光束に変換するコリメータレンズ、（３）は入射光
を分離・反射させる光分離器としてのビームスプリッタ
、（４）はビームスプリッタ（３）で分離された発光源
〈１）からの出射光の一部である光強度検出用光を大刀
し、出射光強度を検出する光検知器、（５）はビームス
プリッタ（３）がらの平行光を光検知器（４）の受光面
何月こ集光させる集光レンズ、（６）は情報が記録され
ており、入射光を反射させる情報記録担体、（７）はビ
ームスプリッタ（３）で分離された発光源（１）からの
出射光の一部である情報読取り用光を情報記録担体（６
）上に集光させる対物レンズ、（８）は情報記録担体（
６）で反射され、ビームスプリッタ（３）によって進行
方向を曲げられた光束を分離して、信号再生・検出系（
７）（７）それぞれに導くビームスプリッタである。こ
の第１の信号再生・検出系（７）は、例えばブツシュ・
プル方式によりトラックエラー信号を検出するための光
検知器■υと、この光検知器？υの受光面（２１１）に
ビームスプリッタ（８）からの光束を集光させる集光レ
ンズ四とから構成され、第２の信号再生・検出系山は、
例えば非点収差法によりフォーカスエラー信号を検出す
るための光検知器６１）と、非点収差発生のための円筒
レンズに）と、光検知器６１）の受光面（８１１）にビ
ームスプリッタ（８）からの光束を円筒レンズ□を介し
て集光させる集光レンズμｓとから構成されている。FIG. 4 is a schematic diagram showing a conventional optical reproducing device, and FIG. 5 is a partially enlarged view thereof. In the figure, (1) is a light emitting source such as a semiconductor laser that generates a light beam for reproduction, (2) is a collimator lens that converts the divergent light beam emitted from the light source (1) into a parallel light beam, and (3) (4) is a beam splitter that separates and reflects incident light, and (4) is a beam splitter that uses light intensity detection light that is part of the light emitted from the light source (1) separated by the beam splitter (3). , a photodetector that detects the intensity of the emitted light, (5) a condenser lens that focuses the parallel light from the beam splitter (3) on the light receiving surface of the photodetector (4), and (6) an information is recorded on the information recording carrier and reflects the incident light, and (7) is the information recording carrier that reflects the information reading light, which is a part of the emitted light from the light emitting source (1) separated by the beam splitter (3). (6
), the objective lens (8) focuses the light onto the information recording carrier (
6) and whose traveling direction is bent by the beam splitter (3) is separated and sent to the signal regeneration/detection system (
7) (7) A beam splitter that guides each. This first signal regeneration/detection system (7) includes, for example, a bush.
A photodetector ■υ for detecting track error signals using the pull method and this photodetector? The second signal regeneration/detection system consists of four condenser lenses that condense the light beam from the beam splitter (8) onto the light receiving surface (211) of υ.
For example, a photodetector 61) for detecting a focus error signal by the astigmatism method, a cylindrical lens for generating astigmatism), a beam splitter (811) for the light receiving surface (811) of the photodetector 61), ) and a condensing lens μs that condenses the light beam from the cylindrical lens □.
なお、情報信号再生は、光検知器ＷＵ又はｃ３υのいず
れかあるいは両方の光検知器＜２１） １３１）を用い
て行われる。また、出射光強度検出用光検知器（４）か
らの検出信号は発光源（１）へ出力され、この検出信号
に基づいて発光ｉｎ）からの出射光強度が調整されてい
る。Note that the information signal reproduction is performed using one or both of the photodetectors WU and c3υ. Further, a detection signal from the light detector (4) for detecting the intensity of emitted light is output to the light emitting source (1), and the intensity of the emitted light from the light emitting in) is adjusted based on this detection signal.
以上のように構成されでいる従来の光学的再生装置にオ
０゛いては、再生信号に無視できない雑音が生じ、信号
対雑音比が悪いという問題点がｉｌ、った。The conventional optical reproducing apparatus configured as described above has the problem that non-negligible noise occurs in the reproduced signal and the signal-to-noise ratio is poor.
つまり、従来の装置では出射光強度検出用光検知器（４
）及び信号再生用光検知器ｇＩ）ｏυがそれぞれ光学的
に兵役点に置かｉしているので、第６図に示す如く受光
面（ロ）に入射量る光の一部が破線で示すように反射さ
れ、ハーフプリズムであるビームスプリッタ（３） （
８）を通り、再生信号を検出する光検知器Ｑ１）Ｏｐの
受光面（２１１） （８１１）上に集光されていた。こ
のため、情報記録担体（６）からの再生信号光と光検知
器（４）からの反射光とが同一光路中にＭ畳し、この反
射光が信号再生用光検知器ｚＨυの受光面（２１１Ｘ８
１１）に入射して、再生信号中のシせット雑音及び光源
雑音等の雑音を増大させるという現象を引き起こすとい
う問題点があり、この現象が再生信号の信号対雑音比を
低下させる要因となっていた。In other words, in the conventional device, a photodetector (4
) and the signal reproducing photodetector gI) oυ are each optically placed at the military service point, so as shown in Figure 6, a portion of the light incident on the light receiving surface (b) is as shown by the broken line. beam splitter (3), which is a half prism (
8), and was focused on the light receiving surface (211) (811) of the photodetector Q1) Op which detects the reproduced signal. Therefore, the reproduced signal light from the information recording carrier (6) and the reflected light from the photodetector (4) are folded M in the same optical path, and this reflected light reaches the light receiving surface ( 211X8
11), which causes a phenomenon of increasing noise such as shitt noise and light source noise in the reproduced signal, and this phenomenon is a factor that reduces the signal-to-noise ratio of the reproduced signal. It had become.
この発明は上記のような問題点を解消するためになされ
たもので、容易に再生信号の信号対雑音比を向とさせる
安価な光学的再生装置を提供することを１的とする。The present invention has been made to solve the above-mentioned problems, and one object thereof is to provide an inexpensive optical reproducing device that can easily improve the signal-to-noise ratio of a reproduced signal.
この発明の第１の発明に係る光学的再生装置は、発光静
からの出射光を情報読取り用光と光強度検出用光とに分
離する光分離器と、この光強度検出用光により発光源か
らの出射光の光強ｇｔを検出し、上記発光源へ光強度調
瞠うのための信号を出力する光検知器との間に光′ＥＡ
衰器を設けたものである。The optical reproducing device according to the first aspect of the present invention includes a light separator that separates the light emitted from the light emitting station into light for information reading and light for light intensity detection, and a light emitting source using the light intensity detection light. The light 'EA' is connected to a photodetector that detects the light intensity gt of the emitted light from the light emitting source and outputs a signal for adjusting the light intensity to the light emitting source.
It is equipped with an attenuator.
また、この発明の第２の発１に係る光学的再生装置は、
光分臼１．器からの光強度検出用光により発光源からの
出射光の光強度を検出し、上記発光ａへ光強度調整のた
めの信号を出力する光検知器の受光面上に接して光色反
則膜を形成させたものである。Further, the optical reproduction device according to the second aspect 1 of the present invention includes:
Optical mill 1. A light color reversing film is in contact with the light receiving surface of the photodetector which detects the light intensity of the light emitted from the light emitting source using the light intensity detection light from the light emitting device and outputs a signal for adjusting the light intensity to the light emitting a. is formed.
この発明の第１の発明における光減衰器は、光分穴１（
器からの光強度検出用光を入力し、発光源へ光強度調整
のための信号を出力する光検知器の受光面からの該光強
度検出用光の反射光を減衰させ、（ビ号再生系への１影
でツを抑制する。The optical attenuator in the first aspect of the present invention has an optical attenuation hole 1 (
The reflected light of the light intensity detection light from the light receiving surface of the photodetector which outputs a signal for light intensity adjustment to the light emitting source is attenuated. Suppress Tsu by one shadow on the system.
この発明の第２の発明における光無反射欣は、光分＾；
１器からの光強度検出用光を入力し、発光源へ光強度調
整のための信号を出力する光検知器の受光面に入射する
該光強度検出用光を反１ｊさせず、信号再生系への悪影
響を防止する。The light non-reflection in the second invention of this invention is light fraction ^;
A signal regeneration system that inputs light intensity detection light from one device and outputs a signal for light intensity adjustment to the light emitting source without causing the light intensity detection light incident on the light receiving surface of the photodetector to be reversed. prevent adverse effects on
以下、この発明の一実施例を図について説明する。第１
図１：ａ） （ｂ）において、従来装置と同一符号は同
−又は相当部分であり、（９）は集光レンズ（５）と光
検知器（４）との間に設けられ、通過する光の光量を減
衰させる光減衰器である。An embodiment of the present invention will be described below with reference to the drawings. 1st
In Figure 1:a) and (b), the same reference numerals as in the conventional device indicate the same or equivalent parts, and (9) is provided between the condenser lens (5) and the photodetector (4), This is an optical attenuator that attenuates the amount of light.
どＩ５に、動作について説明する。発光源（１）からの
出射光は、第１図（ａ）に示す破線のように光分部器と
してのビームスプリッタ（３）によって一部反射され、
集光レンズ（５）によって集光され、光減衰器（９）を
透過して光検知器（４）へ入射する。この入射した光は
、第１図（ｂ）に示す破線のように、受光面（４ηで反
射され、再び光減衰器（９）を透過し、ビームスプリッ
タ（３）を透過してビームスプリッタ（８）へ入射する
。つまり、受光面向からの反射光は、光減衰器（９）に
よって十分に減衰され、信号再生用光検知器ンυ（翅へ
はほとんど入射しなくなる。Next, the operation will be explained. The emitted light from the light emitting source (1) is partially reflected by the beam splitter (3) as a light splitter, as shown by the broken line in FIG. 1(a).
The light is focused by a focusing lens (5), passes through an optical attenuator (9), and enters a photodetector (4). This incident light is reflected by the light receiving surface (4η), passes through the optical attenuator (9) again, passes through the beam splitter (3), and passes through the beam splitter (3), as shown by the broken line in FIG. 1(b). In other words, the reflected light from the light-receiving surface is sufficiently attenuated by the optical attenuator (9), and almost no longer enters the signal reproducing photodetector (wing).
なお、上記実施例では、集光レンズ（５）と光検出器（
４）との間に光減衰器（９）を設けたものを示したが、
第２図（ａ）に示すように、光減衰器（９）を光検知器
（４）の受光面ｉ；Ｊ側に光検出器（４）と一体化させ
設けたものであってもよく、あるいは第２図（ｂ）に示
すように、光減衰器（９）をビームスプリッタ（３）と
集光レンズ（５）との間に設けてもよい。また、上記実
施例では光減衰器（９）を用いたものについて示したが
、第８図に示すように、光検知器（４）の受光面＠Ｖ上
に接して例えば誘電体多層膜から成る光熱反射膜ＯＯを
施したものであってもよく、上記実施例と同様の効果を
奏し、反射光の発生を防止しているのでさらに上記光減
衰器（９１を用いた実施例より信号対雑音比の向上が図
れるものとなる。In addition, in the above embodiment, the condenser lens (5) and the photodetector (
4) is shown in which an optical attenuator (9) is provided between the
As shown in FIG. 2(a), an optical attenuator (9) may be integrated with the photodetector (4) on the light receiving surface i; J side of the photodetector (4). Alternatively, as shown in FIG. 2(b), an optical attenuator (9) may be provided between the beam splitter (3) and the condenser lens (5). In the above embodiment, the optical attenuator (9) is used, but as shown in FIG. The optical attenuator (91) may be applied with a light-heat reflective film OO, which produces the same effect as the above embodiment and prevents the generation of reflected light. This makes it possible to improve the noise ratio.
以上のように、この発明の第１の発明によれば、発光源
からの出射光の光強度を検出する光検知器の受光面から
の反射光を光減衰器にて減、衰させるように構成したの
で、装置を大型化することなく、安価で性能の良い光学
的再生装置を得ることができる効果がある。As described above, according to the first aspect of the present invention, the light reflected from the light receiving surface of the photodetector that detects the light intensity of the light emitted from the light emitting source is attenuated or attenuated by the light attenuator. This configuration has the effect of making it possible to obtain an inexpensive and high-performance optical reproducing device without increasing the size of the device.
才だ、この発明の第２の発明によれは、発光源からの出
射光の光強度を検出する光検知器の受光面における反射
を光熱反射膜にて防止するように構成したので、装置を
大型化することなく、安価で性能の良い光学的再生袋ｆ
ｆ１４得ることができる効果がある。According to the second aspect of the invention, the device is configured to prevent reflection on the light-receiving surface of the photodetector that detects the light intensity of the light emitted from the light-emitting source using a light-heat reflective film. Optical recycling bag that is inexpensive and has good performance without increasing its size f
There are effects that can be obtained with f14.
第１図（ａ） （ｂ）はこの第１の発明の一実施例によ
る光学的再生装置における出射光強度検出用光検知器へ
の入射光の経路及び出射光強度検出用光検知器からの反
射光の経路を示す部分拡大図、第２図（ａ） （ｂｌは
この第１の発明の他実施例を示す光学的再生装置の部分
拡大図、第８因はこの第２の発明の一実施例を示す光学
的再生装置の部分拡大図、第４図は従来の光学的再生装
置を示す概略図、第５図は従来の光学的再生装置におけ
る出射光強度検出用光検知器への入射光の経路を示す部
分拡大図、第６図は従来の光学的再生装置における出射
光強度検出用光検知器からの反射光の経路を示す部分拡
大図である。図において、（１）は発光源、（３）は光
分離器、（４）ば光検知器、ｔ４１１１よ受光面、（９
）は光減衰器、 ｆＩＱは光熱反射膜である。
なお、図中、同一符号は同一、又は相当部分を示す。FIGS. 1(a) and 1(b) show the path of incident light to the photodetector for detecting the intensity of emitted light and the path from the photodetector for detecting the intensity of emitted light in the optical reproducing device according to an embodiment of the first invention. FIG. 2(a) is a partially enlarged view showing the path of reflected light. FIG. 4 is a schematic diagram showing a conventional optical reproducing device; FIG. 5 is a diagram showing the incident light on a photodetector for detecting the intensity of output light in the conventional optical reproducing device. FIG. 6 is a partially enlarged view showing the path of light reflected from a photodetector for detecting the intensity of emitted light in a conventional optical reproducing device. source, (3) is a light separator, (4) is a photodetector, t4111 is a light receiving surface, (9
) is an optical attenuator, and fIQ is a photothermal reflective film. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.
Claims (2)
この発光源からの出射光を情報読取り用光と光強度検出
用光とに分離する光分離器と、この光分離器からの光強
度検出用光により上記発光源からの出射光強度を検出し
、上記発光源へ光強度調整のための信号を出力する光検
知器と、これら光分離器と光検知器との間に設けられ、
上記光検知器の受光面からの上記光強度検出用光の反射
光を減衰させる光減衰器とを備えた光学的再生装置。(1) a light emitting source that generates a light beam to the information recording carrier;
A light separator separates the light emitted from the light source into information reading light and light intensity detection light, and the light intensity detection light from the light separator detects the light intensity emitted from the light source. , a photodetector that outputs a signal for adjusting light intensity to the light emitting source, and a photodetector provided between the light separator and the photodetector,
and an optical attenuator that attenuates the reflected light of the light intensity detection light from the light receiving surface of the photodetector.
この発光源からの出射光を情報読取り用光と光強度検出
用光とに分離する光分離器と、この光分離器からの光強
度検出用光により上記発光源からの出射光強度を検出し
、上記発光源へ光強度調整のための信号を出力する光検
知器と、この光検知器の受光面上に接して形成され、こ
の受光面からの上記光強度検出用光の光反射を防止する
光無反射膜とを備えた光学的再生装置。(2) a light emitting source that generates a light beam to the information recording carrier;
A light separator separates the light emitted from the light source into information reading light and light intensity detection light, and the light intensity detection light from the light separator detects the light intensity emitted from the light source. , a photodetector that outputs a signal for adjusting the light intensity to the light emitting source, and a photodetector formed in contact with the light receiving surface of the photodetector to prevent light reflection of the light intensity detection light from the light receiving surface. An optical reproducing device equipped with a light non-reflection film.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62038556A JPH0711871B2 (en) | 1987-02-20 | 1987-02-20 | Optical playback device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62038556A JPH0711871B2 (en) | 1987-02-20 | 1987-02-20 | Optical playback device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63205826A true JPS63205826A (en) | 1988-08-25 |
| JPH0711871B2 JPH0711871B2 (en) | 1995-02-08 |
Family
ID=12528565
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62038556A Expired - Fee Related JPH0711871B2 (en) | 1987-02-20 | 1987-02-20 | Optical playback device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0711871B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04221441A (en) * | 1990-12-25 | 1992-08-11 | Mitsubishi Electric Corp | Jig for measuring laser power of optical disk device |
-
1987
- 1987-02-20 JP JP62038556A patent/JPH0711871B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04221441A (en) * | 1990-12-25 | 1992-08-11 | Mitsubishi Electric Corp | Jig for measuring laser power of optical disk device |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0711871B2 (en) | 1995-02-08 |
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| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |