JPH0651784A - Hybrid silencer - Google Patents
Hybrid silencerInfo
- Publication number
- JPH0651784A JPH0651784A JP4201245A JP20124592A JPH0651784A JP H0651784 A JPH0651784 A JP H0651784A JP 4201245 A JP4201245 A JP 4201245A JP 20124592 A JP20124592 A JP 20124592A JP H0651784 A JPH0651784 A JP H0651784A
- Authority
- JP
- Japan
- Prior art keywords
- splitter
- sound absorbing
- duct
- sound
- silencer
- 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
Landscapes
- Pipe Accessories (AREA)
- Soundproofing, Sound Blocking, And Sound Damping (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明はダクト内を伝わって来る
送風機音等を消音する消音装置に関し、特に受動型及び
能動型を組み合せたハイブリッド消音装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a muffler for silencing blower noise and the like transmitted through a duct, and more particularly to a hybrid muffler combining a passive type and an active type.
【０００２】[0002]
【従来の技術】第７図に従来のハイブリッド消音装置を
示してある。１は消音すべきダクトで、同ダクト１内に
は図示のように受動型消音器と能動型消音器が直列に配
設されている。2. Description of the Related Art FIG. 7 shows a conventional hybrid silencer. Reference numeral 1 denotes a duct to be silenced. Inside the duct 1, a passive silencer and an active silencer are arranged in series as shown.
【０００３】受動型消音器は、ダクト１内を長さ方向に
複数個に仕切る吸音スプリッタ２で構成されており、吸
音スプリッタ２は多孔板３で形成されている。The passive silencer is composed of a sound absorbing splitter 2 which divides the inside of the duct 1 into a plurality of parts in the length direction, and the sound absorbing splitter 2 is formed of a perforated plate 3.
【０００４】能動型消音器は、ダクト１に取付けられた
検出マイクロホン４と誤差マイクロホン５、消音用スピ
ーカ６及び能動消音制御装置７で構成されている。The active silencer comprises a detection microphone 4 attached to the duct 1, an error microphone 5, a silencer speaker 6 and an active silencer control device 7.
【０００５】受動型消音器は吸音スプリッタ２によって
主として高周波音域を消音するものであり、能動型消音
器はダクト内１を伝播してくる原音を検出マイクロホン
４で検出した信号を能動消音制御装置７において、誤差
マイクロホン５の信号が最小となる様に信号処理を行
い、消音用スピーカ６より制御用の音を発生し、主とし
て低周波音域を消音するものである。The passive silencer mainly silences the high frequency range by the sound absorbing splitter 2, and the active silencer detects the original sound propagating in the duct 1 by the detection microphone 4 and the active silencer 7 In (1), signal processing is performed so that the signal of the error microphone 5 is minimized, and a control sound is generated from the muffling speaker 6 to mute mainly the low frequency range.
【０００６】従来は、受動型及び能動型消音器をそれぞ
れ単独、または図示のように両者を直列に配置し使用し
ていた。吸音材を用いた受動型消音器は、単独で使用す
ると、低周波音域での減音効果が悪く、それをカバーし
ようとすると、非常に大がかりな物になってしまうとい
う欠点があり、能動型消音器単独では、高周波音域の消
音が不可能であるという欠点があった。Conventionally, passive type and active type silencers have been used individually, or as shown in the figure, both have been arranged in series and used. A passive silencer using a sound absorbing material has a drawback that when used alone, it has a poor sound-reducing effect in the low-frequency range, and if it is attempted to cover it, it becomes a very large-scaled one. There is a drawback in that it is impossible to muffle the high frequency range by using the muffler alone.
【０００７】また、受動型、能動型消音器を直列に配置
すると全周波数域で減音効果が得られるが、ダクト全長
が非常に長くなる等の欠点があった。Further, if passive and active silencers are arranged in series, a sound reduction effect can be obtained in the entire frequency range, but there is a drawback that the total length of the duct becomes very long.
【０００８】また従来の能動型消音器ではマイクロホ
ン、制御スピーカ、コントローラ等をダクト壁に設置し
ていたため、大型ダクトに能動型消音器を複数個設置す
る場合は図８に示すように無駄なスペースＳが大きくな
り、かつ、能動型消音器のメンテナンスが難しいなどの
欠点があった。Further, in the conventional active silencer, a microphone, a control speaker, a controller, etc. are installed on the duct wall. Therefore, when a plurality of active silencers are installed in a large duct, a wasteful space is provided as shown in FIG. There are drawbacks such that S becomes large and the maintenance of the active silencer is difficult.
【０００９】また、制御用スピーカを複数個設置する場
合、相互干渉による音響放射効率の低下がおこらないよ
うに工夫する必要がある。更に、マイクロホンが気流ノ
イズを検出して音波とのＳ／Ｎ比が悪化することのない
ように配慮する必要があった。Further, when a plurality of control speakers are installed, it is necessary to devise so as not to reduce the acoustic radiation efficiency due to mutual interference. Further, it is necessary to consider so that the microphone does not detect the airflow noise and the S / N ratio with the sound wave is deteriorated.
【００１０】[0010]
【発明が解決しようとする課題】本発明は、受動型及び
能動型の両消音器を組み合せて全周波数域で消音効果を
得られるようにしながらも、従来のもののように無駄な
スペースをとらない装置を提供することを課題としてい
る。また、本発明はマイクロホンが気流ノイズのために
Ｓ／Ｎ比を悪くすることのない構造の消音装置を提供す
ることをも課題としている。DISCLOSURE OF THE INVENTION The present invention combines both passive and active silencers to obtain a silencing effect in the entire frequency range, but does not occupy a wasted space unlike conventional ones. An object is to provide a device. Another object of the present invention is to provide a silencer having a structure in which the microphone does not deteriorate the S / N ratio due to airflow noise.
【００１１】更に、本発明は能動型消音装置において複
数個の制御用スピーカが相互干渉することのない構造を
採用した消音装置を提供することを課題としている。ま
た、本発明は、メンテナンスのために分解と取り外しが
容易な構造の消音装置を提供することをも課題としてい
る。It is another object of the present invention to provide a silencer that employs a structure in which a plurality of control speakers do not interfere with each other in an active silencer. Another object of the present invention is to provide a silencer having a structure that can be easily disassembled and removed for maintenance.
【００１２】[0012]
【課題を解決するための手段】前記した課題を解決する
ため、本発明では消音すべきダクト内に吸音スプリッタ
を挿入してダクト内を複数個に仕切り、その吸音スプリ
ッタ内に能動消音装置の構成に必要な装置（検出マイク
ロホン、誤差マイクロホン、制御用スピーカ、消音制御
装置，増巾器、電源等）を装着させる。In order to solve the above-mentioned problems, in the present invention, a sound absorbing splitter is inserted into a duct to be muffled to partition the inside of the duct into a plurality of parts, and an active muffling device is constructed in the sound absorbing splitter. Install necessary devices (detection microphone, error microphone, control speaker, muffler control device, amplifier, power supply, etc.).
【００１３】また、本発明は前記した課題を解決するた
め、マイクロホンの一方を吸音スプリッタの先頭部淀み
点部に、他方のマイクロホンを吸音スプリッタを挟んで
整流板を設置して形成された淀み点部に配設しマイクロ
ホンに対し気流ノイズが悪影響を与えない構造を採用す
る。In order to solve the above-mentioned problems, the present invention has a stagnation point formed by installing one of the microphones at the stagnation point of the head of the sound absorbing splitter and the other microphone with a rectifying plate sandwiching the sound absorbing splitter. Adopted a structure that is installed in the section so that airflow noise does not adversely affect the microphone.
【００１４】また、本発明は能動消音装置において複数
のスピーカを設置する場合、それらのスピーカの間の相
互作用を避けるため、スプリッタの一面にのみ開いたス
ピーカボックスを設けそこに、スピーカを設置した構造
を採用する。また本発明は、吸音スプリッタをダクトに
対しスライド式に挿入、取り出しできるようにした構造
をも採用する。Further, according to the present invention, when a plurality of speakers are installed in the active silencer, a speaker box opened only on one surface of the splitter is provided and the speakers are installed therein in order to avoid interaction between the speakers. Adopt structure. The present invention also employs a structure in which the sound absorbing splitter can be slidably inserted into and taken out from the duct.
【００１５】[0015]
【作用】本発明においては、ダクト内を複数個の流路に
仕切る吸音スプリッタ内に能動消音装置をすべて収納し
てしまうことにより、コンパクトなスペース内で、高周
波音に有効な受動型の消音と、低周波音に有効な能動型
の消音が同時に可能である。このように本発明によれ
ば、低周波から高周波に至るまで巾広い消音効果を有す
る消音装置が実現できる。According to the present invention, by accommodating all the active silencers in the sound absorbing splitter that divides the duct into a plurality of flow paths, a passive silencer effective for high frequency noise can be provided in a compact space. , Active muffling effective for low frequency sound is possible at the same time. As described above, according to the present invention, it is possible to realize a silencing device having a wide silencing effect from low frequencies to high frequencies.
【００１６】またダクト内に吸音スプリッタを設置して
ダクトを長さ方向に複数個に仕切っているため、通路巾
は狭くなり、単位長当りの受動型の消音効果は更に大き
くなるとの相乗効果を持っている。また本発明によって
マイクロホンをスプリッタ前後の淀み点に設置したもの
では、マイクロホンに対する気流による雑音が低減でき
能動型消音装置の消音限界をより低いレベルにすること
が可能である。Further, since a sound absorbing splitter is installed in the duct to divide the duct into a plurality of parts in the lengthwise direction, the passage width becomes narrower, and the passive type sound deadening effect per unit length is further increased. have. Further, according to the present invention, when the microphone is installed at the stagnation points before and after the splitter, the noise due to the air flow to the microphone can be reduced, and the silencing limit of the active silencer can be set to a lower level.
【００１７】また、本発明においてスピーカボックスを
スプリッタの片面方向のみに開としたものでは、複数の
スピーカは同一方向を向くことになり、スピーカが相互
干渉して発生音効率が低下しない。Further, in the present invention, when the speaker box is opened only in one direction of the splitter, the plurality of speakers face in the same direction, and the speakers do not interfere with each other so that the generated sound efficiency does not decrease.
【００１８】又、本発明においてスプリッタをスライド
式に構成したものでは、能動型消音装置のメンテナンス
が容易になる。Further, in the present invention, when the splitter is constructed in a sliding type, the maintenance of the active silencer becomes easy.
【００１９】[0019]
【実施例】以下、本発明を図示した実施例に基いて具体
的に説明する。図１において、１は消音すべきダクト、
２はダクト１内を長さ方向に複数個の流路に仕切る吸音
スプリッタで、多孔板３によって形成されている。４
は、吸音スプリッタ２の先頭部に外形に合せて埋め込ま
れた検出マイクロホン、５は吸音スプリッタ２の後端部
内に配設された誤差マイクロホンである。EXAMPLES The present invention will be specifically described below based on illustrated examples. In FIG. 1, 1 is a duct to be silenced,
Reference numeral 2 is a sound absorbing splitter that divides the inside of the duct 1 into a plurality of flow paths in the length direction, and is formed by a perforated plate 3. Four
Is a detection microphone embedded in the head portion of the sound absorbing splitter 2 according to the outer shape, and 5 is an error microphone disposed in the rear end portion of the sound absorbing splitter 2.
【００２０】また、６は消音用スピーカ、７は能動消音
制御装置で、いずれも吸音スプリッタ２内に配設されて
いる。吸音スプリッタ２は、図２の横断面図に示すよう
に、気流に対し前の方が従来の受動型の消音器と同様の
構造のままとして構成され、後方は消音用スピーカ６、
消音制御装置７、誤差マイクロホン５が収納されて能動
型の消音装置を構成している。Further, 6 is a muffling speaker, and 7 is an active muffling control device, both of which are arranged in the sound absorbing splitter 2. As shown in the transverse cross-sectional view of FIG. 2, the sound absorbing splitter 2 is configured to have the same structure as that of the conventional passive silencer with respect to the air flow, and the silencer speaker 6 at the rear,
The silence control device 7 and the error microphone 5 are housed to form an active silencer.
【００２１】このように構成された吸音スプリッタ２
は、ダクト１内に配設されたガイドレール８に沿ってダ
クト１から出し入れできる構造となっている。吸音スプ
リッタ２の端部には、図３に示すように、スプリッタ２
の内部の制御装置等に接続されたコンセントが設けられ
ており、スプリッタ２をダクト１に出し入れするときに
ダクト側の配線に着脱できるようになっており、メンテ
ナンスが容易である。The sound absorbing splitter 2 configured as described above
Has a structure that can be taken in and out of the duct 1 along a guide rail 8 arranged in the duct 1. At the end of the sound absorbing splitter 2, as shown in FIG.
An outlet connected to a control device or the like inside is provided so that the splitter 2 can be attached / detached to / from the wiring on the duct side when the splitter 2 is taken in / out of the duct 1, which facilitates maintenance.
【００２２】また、図２に示すように、検出マイクロホ
ン４が埋め込まれている吸音スプリッタ２の先頭部及
び、両側が整流板９で挟まれ誤差マイクロホン５が配設
されたスプリッタ２の後方部分は、ダクト１内で気流が
無い、いわゆる淀み点を形成している。Further, as shown in FIG. 2, the front portion of the sound absorbing splitter 2 in which the detection microphone 4 is embedded and the rear portion of the splitter 2 in which the error microphones 5 are arranged by sandwiching the both sides with the rectifying plates 9 are provided. A so-called stagnation point where there is no air flow in the duct 1 is formed.
【００２３】従って、両マイクロホン４，５の上を気流
が流れることによって発生する新たな気流の乱れと、そ
れによって生ずる圧力変動がそこでは発生しない。この
ように、ダクト内の淀み点にマイクロホンを設置すると
気流による雑音が減り、マイクロホンのＳ／Ｎ比を良く
する。Therefore, new turbulence of the air flow generated by the air flow flowing over the microphones 4 and 5 and the pressure fluctuation caused thereby are not generated there. As described above, when the microphone is installed at the stagnation point in the duct, noise due to the air flow is reduced, and the S / N ratio of the microphone is improved.
【００２４】なお、図２に示すように、淀み点を形成す
る整流板９の後縁にスクリーン１０などを設置してその
部分のスプリッタ内に気流が入り込まないようにすると
尚良い。As shown in FIG. 2, it is more preferable to install a screen 10 or the like at the rear edge of the straightening plate 9 forming the stagnation point so that the air flow does not enter the splitter at that portion.
【００２５】図１では、消音用スピーカ６を２個設置し
た例を示しているが、スピーカボックスは必ず一方向に
開いた構造とし、２つのスピーカ６の間で音響的な短絡
が生じて音の反射効率が低下しないように工夫されてい
る。Although FIG. 1 shows an example in which two muffling speakers 6 are installed, the speaker box is always open in one direction, and an acoustic short circuit occurs between the two speakers 6 to produce a sound. It is designed so that the reflection efficiency of is not reduced.
【００２６】図４は図１に示した消音ユニットを断面積
の大きいダクト内に複数個設置した様子を示す。能動消
音装置がスプリッタ内に完全におさまっているため、図
８の従来の装置に見られるような無駄スペースは発生し
ない。FIG. 4 shows a plurality of muffling units shown in FIG. 1 installed in a duct having a large cross section. Since the active silencer is completely contained within the splitter, there is no wasted space as found in the prior art device of FIG.
【００２７】以上、本発明を実施例に基いて説明した
が、本発明はこれらに限定されず、本発明の範囲内で種
々変更を加えてよいことはいうまでもない。例えば、図
示した装置では、吸音スプリッタのメンテナンスを容易
にするため、吸音スプリッタをダクトに対し着脱自在の
構造としているが、メンテナンスの頻度が少い場合に
は、吸音スプリッタはダクト内に固定した構造としても
よい。また、マイクロホンを設置する淀み点も図示した
もの以外、適宜の構造のものとしてよい。Although the present invention has been described based on the embodiments, it goes without saying that the present invention is not limited to these and various changes may be made within the scope of the present invention. For example, in the illustrated device, the sound absorbing splitter is detachably attached to the duct in order to facilitate maintenance of the sound absorbing splitter. However, when the frequency of maintenance is low, the sound absorbing splitter is fixed in the duct. May be Further, the stagnation point where the microphone is installed may have an appropriate structure other than that shown in the drawing.
【００２８】[0028]
【発明の効果】図５には、図１に示した本発明による装
置の消音効果の例を示す。能動消音装置（ＡＮＣ）を作
動させないときは低周波成分の消音効果が悪いのに対
し、能動消音装置を作動させることにより低周波成分が
大きく消音し、広帯域周波数にわたって、均質な消音が
得られることがわかる。FIG. 5 shows an example of the silencing effect of the device according to the present invention shown in FIG. When the active noise suppressor (ANC) is not operated, the low frequency component has a poor muffling effect. However, when the active noise suppressor is activated, the low frequency component is largely silenced, and a uniform muffling is obtained over a wide frequency range. I understand.
【００２９】図６はダクト内流速と、消音限界値との関
係を示しており、流速が増すと、気流雑音の関係で消音
器出口の音圧レベルをある値以下に下げることはできな
くなる。本発明による装置のように、マイクロホンを淀
み点に設置することによりその限界値を１０ｄＢ以上下
げることができる。FIG. 6 shows the relationship between the flow velocity in the duct and the muffling limit value. When the flow velocity increases, the sound pressure level at the muffler outlet cannot be lowered below a certain value due to air flow noise. As in the device according to the present invention, the limit value can be lowered by 10 dB or more by installing the microphone at the stagnation point.
【００３０】その他本発明による装置の効果を以下に追
記する。 （１）受動型と能動型の消音器を一体化することによ
り、ダクト全長を短くすることができる。 （２）能動消音装置にかかわる部分をすべて吸音スプリ
ッタ内に設置し、かつ、その吸音スプリッタをダクトか
ら引出し可としたとこにより、メンテナンスが容易であ
るとともに、外壁に付属する突起物を無くすることがで
きるため、無駄なスペースなくダクトを仕切ることが可
能となる。Other effects of the device according to the present invention will be additionally described below. (1) The total length of the duct can be shortened by integrating the passive silencer and the active silencer. (2) All the parts related to the active noise suppressor are installed in the sound absorbing splitter, and the sound absorbing splitter can be pulled out from the duct, which facilitates maintenance and eliminates protrusions attached to the outer wall. Therefore, it is possible to partition the duct without wasting space.
【図１】本発明の１実施例によるハイブリッド消音装置
を１部破断して示す斜視図、FIG. 1 is a perspective view showing a hybrid silencer according to an embodiment of the present invention with a part broken away;
【図２】図１に示した消音装置の横断面図、FIG. 2 is a cross-sectional view of the silencer shown in FIG.
【図３】吸音スプリッタの端部の状況を示す部分的斜視
図、FIG. 3 is a partial perspective view showing a state of an end portion of a sound absorbing splitter,
【図４】本発明による消音装置の他の実施例を示す斜視
図、FIG. 4 is a perspective view showing another embodiment of the silencer according to the present invention,
【図５】本発明による消音装置の減音効果を示すグラ
フ、FIG. 5 is a graph showing the noise reduction effect of the silencer according to the present invention,
【図６】本発明による消音装置の効果を示すグラフ、FIG. 6 is a graph showing the effect of the silencer according to the present invention,
【図７】従来の消音装置を示す斜視図、FIG. 7 is a perspective view showing a conventional silencer,
【図８】従来の消音装置の他の例を示す斜視図、FIG. 8 is a perspective view showing another example of a conventional silencer,
１ ダクト ２ 吸音スプリッタ ３ 多孔板 ４ 検出マイクロホン ５ 誤差マイクロホン ６ 消音用スピーカ ７ 能動消音制御装置 ８ ガイドレール ９ 整流板 １０ スクリーン 1 Duct 2 Sound Absorption Splitter 3 Perforated Plate 4 Detection Microphone 5 Error Microphone 6 Noise Suppression Speaker 7 Active Noise Reduction Controller 8 Guide Rail 9 Rectifier 10 Screen
Claims (6)
ト内を長さ方向に複数個に仕切る吸音スプリッタ、及び
同吸音スプリッタ内に配設され消音すべき音と逆位相の
音を発する能動消音装置を有することを特徴とするハイ
ブリッド消音装置。1. A sound absorbing splitter which is arranged in a duct to be silenced and partitions the inside of the duct into a plurality of parts in the longitudinal direction, and a sound which is arranged in the sound absorbing splitter and has a phase opposite to that of the sound to be silenced. A hybrid muffler having an active muffler.
の１端部に配設された検出マイクロホンと、前記吸音ス
プリッタの他端部に配設された誤差マイクロホンと、前
記両マイクロホンの間の前記吸音スプリッタ内に配設さ
れ前記逆位相の音を発する制御用音発生装置を有するこ
とを特徴とする請求項１記載のハイブリッド消音装置。2. A detection microphone in which the active silencer is arranged at one end of the sound absorbing splitter, an error microphone arranged in the other end of the sound absorbing splitter, and the sound absorbing between the both microphones. 2. The hybrid silencer according to claim 1, further comprising a control sound generator that is disposed in the splitter and that emits the sound of the opposite phase.
リッタの先頭部淀み点部に埋め込み、前記マイクロホン
の他方を前記吸音スプリッタを挟んで整流板を設置して
形成された淀み点部に配設し、消音すべき音波が進入し
て来る方向のマイクロホンを前記検出マイクロホンとす
ることを特徴とする請求項２記載のハイブリッド消音装
置。3. One of the microphones is embedded in a stagnation point portion of a head portion of the sound absorbing splitter, and the other of the microphones is disposed at a stagnation point portion formed by installing a rectifying plate with the sound absorbing splitter interposed therebetween. The hybrid silencer according to claim 2, wherein a microphone in a direction in which a sound wave to be silenced enters is used as the detection microphone.
能動消音装置が同吸音スプリッタの一方側にのみ開いた
スピーカボックスに設置されたスピーカを有することを
特徴とする請求項１，２又は３記載のハイブリッド消音
装置。4. The active muffling device arranged in the sound absorbing splitter has a speaker installed in a speaker box opened only on one side of the sound absorbing splitter. The hybrid silencer described.
内に着脱可能に装着されていることを特徴とする請求項
１，２，３又は４記載のハイブリッド消音装置。5. The hybrid silencer according to claim 1, 2, 3 or 4, wherein the sound absorbing splitter is detachably mounted in a duct to be silenced.
差マイクロホンが取付けられ、両マイクロホンの間に吸
音用多孔板、消音用スピーカ及び消音制御装置が組み込
まれると共に接続用コンセントを有するハイブリッド消
音装置用吸音スプリッタ。6. A hybrid muffler having a detection microphone at one end and an error microphone at the other end, a sound absorbing porous plate, a muffling speaker, and a muffling control device being incorporated between the both microphones and having a connection outlet. Sound absorption splitter for equipment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP04201245A JP3137445B2 (en) | 1992-07-28 | 1992-07-28 | Hybrid silencer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP04201245A JP3137445B2 (en) | 1992-07-28 | 1992-07-28 | Hybrid silencer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0651784A true JPH0651784A (en) | 1994-02-25 |
| JP3137445B2 JP3137445B2 (en) | 2001-02-19 |
Family
ID=16437748
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP04201245A Expired - Fee Related JP3137445B2 (en) | 1992-07-28 | 1992-07-28 | Hybrid silencer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3137445B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008003425A (en) * | 2006-06-23 | 2008-01-10 | Nippon Zeon Co Ltd | Polarizing plate |
| JP2008003426A (en) * | 2006-06-23 | 2008-01-10 | Nippon Zeon Co Ltd | Polarizing plate |
| JP2008134384A (en) * | 2006-11-28 | 2008-06-12 | Kyoritsu Kagaku Sangyo Kk | Polarizing plate |
| JP2008152120A (en) * | 2006-12-19 | 2008-07-03 | Nippon Zeon Co Ltd | Optical film |
-
1992
- 1992-07-28 JP JP04201245A patent/JP3137445B2/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008003425A (en) * | 2006-06-23 | 2008-01-10 | Nippon Zeon Co Ltd | Polarizing plate |
| JP2008003426A (en) * | 2006-06-23 | 2008-01-10 | Nippon Zeon Co Ltd | Polarizing plate |
| JP2008134384A (en) * | 2006-11-28 | 2008-06-12 | Kyoritsu Kagaku Sangyo Kk | Polarizing plate |
| JP2008152120A (en) * | 2006-12-19 | 2008-07-03 | Nippon Zeon Co Ltd | Optical film |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3137445B2 (en) | 2001-02-19 |
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