JP2781388B2 - Manufacturing method of flat display tube - Google Patents

Manufacturing method of flat display tube

Info

Publication number
JP2781388B2
JP2781388B2 JP63061087A JP6108788A JP2781388B2 JP 2781388 B2 JP2781388 B2 JP 2781388B2 JP 63061087 A JP63061087 A JP 63061087A JP 6108788 A JP6108788 A JP 6108788A JP 2781388 B2 JP2781388 B2 JP 2781388B2
Authority
JP
Japan
Prior art keywords
frit layer
envelope
melting point
melting
point frit
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.)
Expired - Lifetime
Application number
JP63061087A
Other languages
Japanese (ja)
Other versions
JPH01235125A (en
Inventor
肇 田川
政和 中沢
Original Assignee
松下電子工業株式会社
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 松下電子工業株式会社 filed Critical 松下電子工業株式会社
Priority to JP63061087A priority Critical patent/JP2781388B2/en
Publication of JPH01235125A publication Critical patent/JPH01235125A/en
Application granted granted Critical
Publication of JP2781388B2 publication Critical patent/JP2781388B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Landscapes

  • Manufacture Of Electron Tubes, Discharge Lamp Vessels, Lead-In Wires, And The Like (AREA)
  • Gas-Filled Discharge Tubes (AREA)

Description

【発明の詳細な説明】 産業上の利用分野 本発明は、プラズマ・ディスプレイ・パネル(PDP)
等の偏平型表示管の製造方法、とくに、透明な前面基板
と背面基板とを、両基板間に介在させた枠状の低融点フ
リット層によって気密に封着し、同表示管の外囲器を形
成する方法に関するものである。
The present invention relates to a plasma display panel (PDP).
And the like, in particular, a transparent front substrate and a rear substrate are hermetically sealed by a frame-like low melting point frit layer interposed between the two substrates, and an envelope of the display tube is provided. And a method for forming the same.

従来の技術 一般に、PDP等の偏平型表示管の外囲器は、特公昭53
−9833号公報および特公昭52−46072号公報等に開示さ
れているように、ともにガラスからなる前面基板と背面
基板とを、両基板間に介在させた枠状の低融点フリット
層で一体に封着することにより得られる。すなわち、第
4図に例示したPDPにおいては、垂直方向に長いストラ
イプ状の電極群1を内面上に有するガラス製の背面基板
2と、水平方向に長いストライプ状の電極群3を内面上
に有する透明ガラス製の前面基板4とを、両基板2,4間
に介在させた枠状の低融点フリット層5で気密に封着し
て外囲器を形成している。ただし、背面基板4の通孔6
に連通する排気用細管7は環状の低融点フリット層8に
よって、そして、背面基板4の通孔9に連通する帽状体
10は環状の低融点フリット層11によって、それぞれ背面
基板4に封着されており、帽状体10内にはゲッタ12が納
められている。なお、封着時の排気用細管7は図に一点
鎖線7aで示すようなパイプ状のものであって、これは排
気工程最終段階のチップオフで、図に実線で示すような
閉塞体となる。
Conventional technology Generally, the envelope of a flat display tube such as a PDP is
As disclosed in JP-9833 Publication and JP-B-52-46072, etc., a front substrate and a rear substrate both made of glass are integrally formed by a frame-like low melting point frit layer interposed between the two substrates. Obtained by sealing. That is, the PDP exemplified in FIG. 4 has a glass back substrate 2 having a vertically long striped electrode group 1 on the inner surface and a horizontally long striped electrode group 3 on the inner surface. A front substrate 4 made of transparent glass is hermetically sealed with a frame-like low melting point frit layer 5 interposed between the substrates 2 and 4 to form an envelope. However, the through holes 6 in the rear substrate 4
The exhaust thin tube 7 communicating with the cap is formed by an annular low melting point frit layer 8 and through the through hole 9 of the rear substrate 4.
Numerals 10 are respectively sealed to the back substrate 4 by an annular low melting point frit layer 11, and a getter 12 is accommodated in the cap-shaped body 10. Note that the evacuation thin tube 7 at the time of sealing is a pipe-shaped one as shown by a one-dot chain line 7a in the figure. .

フリット層5は、低融点フリット粉末をビークルとと
もに混練したペースト状体を、両基板2,4の各内面上に
あらかじめ枠状に印刷して仮焼成しておき、これを重ね
合わせて封着用炉内で540℃に近い温度まで加熱し一体
に溶着したものである。なお、低融点フリットには結晶
質のものと非晶質のものとがあり、前者は加熱によって
結晶化し流動性を失う点および電解現象をほとんど生じ
ない点で後者と異なる。このことから、偏平型表示管の
封着部には、通常、結晶質の低融点フリットが用いられ
ている。
The frit layer 5 is formed by printing a paste-like body obtained by kneading a low-melting frit powder together with a vehicle in the form of a frame on each of the inner surfaces of the substrates 2 and 4 beforehand, preliminarily sintering them, and stacking them to form a sealing furnace. It is heated to a temperature close to 540 ° C and welded together. The low-melting frit is classified into a crystalline type and an amorphous type, and the former is different from the latter in that it is crystallized by heating and loses fluidity, and almost no electrolytic phenomenon occurs. For this reason, a crystalline low melting point frit is usually used for the sealing portion of the flat display tube.

発明が解決しようとする課題 前述のように、両基板2,4を低融点フリット層5で封
着し、かつ、排気用細管7および帽状体10を低融点フリ
ット層8,11で封着することによって外囲器が完成するの
であるが、封着過程での外囲器内で熱膨張した気体の一
部分は、排気用細管7aを通じて排出される。そして、常
温に復する過程での外囲器は減圧によって排気用細管7a
を通じ外気を吸い込むので、外囲器内電極の表面酸化が
進み、この表面酸化の度合いは、排気用細管7aに近い電
極部分でもっとも高くなる。そして、かかる電極の局部
的な表面酸化の痕跡は、その後の活性処理によっても消
失せず、これが、完成した表示管の表示特性に少なから
ぬ悪影響を与える。
Problems to be Solved by the Invention As described above, the two substrates 2 and 4 are sealed with the low melting point frit layer 5, and the exhaust pipe 7 and the cap 10 are sealed with the low melting point frit layers 8 and 11. By doing so, the envelope is completed, and a part of the gas thermally expanded in the envelope during the sealing process is exhausted through the exhaust pipe 7a. Then, the envelope in the process of returning to the room temperature is reduced by the reduced pressure to the exhaust thin tube 7a.
, The surface oxidation of the inner electrode of the envelope proceeds, and the degree of the surface oxidation is highest at the electrode portion near the exhaust pipe 7a. Such traces of local surface oxidation of the electrodes are not lost by the subsequent activation treatment, and this has a considerable adverse effect on the display characteristics of the completed display tube.

そこで、封着工程中における排気用細管7aの先端部を
暫定的に閉塞しておくことが考えられるが、このように
すると、外囲器は低融点フリット層の軟化点を越えた時
点から密封状態となり、内圧が上昇する。このため、封
着部で吹き出し現象が起こり、この吹き出し現象で生じ
た封着部欠陥は、結晶化したフリット層が流動性を失う
こととあいまってそのまま残留し、スローリークの発生
原因となる。
Therefore, it is conceivable to temporarily close the tip of the exhaust thin tube 7a during the sealing process.However, in this case, the envelope is sealed from the time when the softening point of the low melting point frit layer is exceeded. State and the internal pressure rises. For this reason, a blowing phenomenon occurs at the sealing part, and the sealing part defect generated by the blowing phenomenon remains as it is, together with the fact that the crystallized frit layer loses fluidity, and causes a slow leak.

課題を解決するための手段 本発明は、前述のような従来の課題を解決すべくなさ
れたもので、少なくとも1個の通孔を有する背面基板と
透明な前面基板とを、それぞれの内面上に付設した枠状
の結晶質低融点フリット層を介し重ね合わせて締め付け
る一方、先端部で閉塞した排気用細管およびゲッタ収容
用帽状体の少なくとも一方を前記背面基板の外面上に、
環状の非晶質低融点フリット層を介し浮上自在に積み重
ねて前記通孔を覆う。そして、この状態で前記結晶質低
融点フリット層および前記非晶質低融点フリット層を加
熱溶融して気密な外囲器を形成し、かつ、冷却後外囲器
の前記排気用細管の先端部を不活性ガス雰囲気内で切断
する。
Means for Solving the Problems The present invention has been made to solve the conventional problems as described above, and includes a rear substrate having at least one through hole and a transparent front substrate on each inner surface. On the outer surface of the rear substrate, at least one of the exhaust thin tube and the getter housing cap-like body closed at the tip is closed while the frame-like crystalline low melting point frit layer is attached and tightened.
The through-holes are covered by being stacked so as to float freely via an annular amorphous low melting point frit layer. Then, in this state, the crystalline low-melting point frit layer and the amorphous low-melting point frit layer are heated and melted to form an airtight envelope, and after cooling, the distal end portion of the exhaust narrow tube of the envelope is cooled. Is cut in an inert gas atmosphere.

作用 このように、両基板を封着するための枠状の低融点フ
リット層に結晶質のものを用い、先端部で閉塞した排気
用細管またはゲッタ収容用帽状体を背面基板に封着する
ための環状の低融点フリット層に、加熱時流動性の高い
非晶質のものを用い、かつ、前記細管または前記帽状体
を浮上自在に積み重ねると、封着工程中の外囲器内で発
生しまたは熱膨張した分解ガス含有気体の一部が、未軟
化状態にある前記非晶質または結晶質の低融点フリット
層上の積み重ね間隙を通じて外囲器外に排出される。こ
の排出の現象は、前記低融点フリット層が軟化するまで
続き、その後に発生した余圧は、流動化した非晶質低融
点フリット層中を通って漏出する。しかし、この漏出に
よって生じた当該フリット層の欠陥は、その上に積み重
ねられた排気用細管または帽状体の自重もしくは自重と
適当なウエイトの重さとによって、自然に回復し、外気
の吸い込みがないまま完全に密封されることになる。密
封後の外囲器内は、フリット層から発生した濃い炭酸ガ
スで満たされ、電極群は一様に酸化するが、それは後に
施す活性処理によって一様に活性化され、外気を吸い込
むことによって電極表面に局部的に生じる酸化は防止さ
れる。すなわち、活性処理を施しても残る酸化むらの痕
跡を完全になくすことができる。
In this way, a crystalline low-melting point frit layer for sealing the two substrates is made of crystalline material, and the exhaust thin tube or the getter accommodating cap closed at the tip is sealed to the rear substrate. For the annular low-melting point frit layer, an amorphous material having high fluidity at the time of heating is used, and when the thin tubes or the cap-like bodies are stacked so as to float, inside the envelope during the sealing step A portion of the generated or thermally expanded cracked gas-containing gas is discharged out of the envelope through the stack gap on the amorphous or crystalline low melting point frit layer in an unsoftened state. This discharge phenomenon continues until the low melting point frit layer softens, and the remaining pressure generated thereafter leaks through the fluidized amorphous low melting point frit layer. However, the defect of the frit layer caused by the leakage is naturally recovered by the self-weight of the exhaust tubing or the cap-shaped body stacked thereon and the appropriate weight and the outside air is not sucked. It will be completely sealed as it is. The inside of the envelope after sealing is filled with the dense carbon dioxide gas generated from the frit layer, and the electrodes are uniformly oxidized. Oxidation locally occurring on the surface is prevented. That is, even after the activation treatment, traces of the remaining uneven oxidation can be completely eliminated.

封着を終えた外囲器が常温近くまで冷却すると、外囲
器内気圧が低下してくる。したがって、この段階で排気
用細管の先端部を不活性ガス雰囲気中で切断すると、外
囲器内に不活性ガスが吸入される。すなわち、排気用細
管を切断したときに空気が外囲器内に吸入されることが
なくなり、前記切断から排気工程に入るまでに放置時間
があっても、外囲器内に空気が入り込むことによって生
じる不均一な電極酸化を防止することができる。
When the sealed envelope is cooled to near normal temperature, the internal pressure of the envelope decreases. Therefore, at this stage, when the distal end of the exhaust thin tube is cut in an inert gas atmosphere, the inert gas is sucked into the envelope. That is, air is not sucked into the envelope when the exhaust tubing is cut, and air enters the envelope even if there is a standing time from the cutting to the start of the exhaust process. The resulting non-uniform electrode oxidation can be prevented.

実施例 つぎに、本発明を図面に示した実施例とともにさらに
詳しく説明する。
Next, the present invention will be described in more detail with reference to embodiments shown in the drawings.

第1図に示す構成が第3図に示した構成と異なるとこ
ろは、ガラスからなる排気用細管13に先端部で閉塞した
ものを用いている点と、この排気用細管13が背面基板4
の外面上に、環状の非晶質低融点フリット層14を介し浮
上自在に積み重ねられ、通孔6を覆っている点と、細管
13の封着時転倒を防ぐための治具15が背面基板4の外面
上に載置されている点と、排気用細管13の頂部にキャッ
プ状の比較的軽いウエイト16が載せられている点とであ
って、治具15は鍔17を有する筒状部18と、鍔17から下方
へ突出した三脚部19とを備えている。なお、背面基板4
および前面基板2の各内面上に付設されて重ね合わされ
た枠状の低融点フリット層20a,20bには、結晶質の低融
点フリットが用いられている。また、前面基板2と背面
基板4とは封着にさいし、第2図図示のように適数個の
クリップ21および当て板22さらには図外のウエイト等に
よって離脱不能に締め付けられる。排気用細管13が十分
な自重を有している場合は、ウエイト16を省略すること
ができる。また、帽状体10の自重が小さい場合は、帽状
体10にも適当なウエイトを付加する。
The configuration shown in FIG. 1 is different from the configuration shown in FIG. 3 in that an exhaust thin tube 13 made of glass, which is closed at the tip, is used.
On the outer surface of the tubing, a floating amorphous low-melting frit layer 14 is interposed so as to float and cover the through hole 6;
A jig 15 for preventing the 13 from falling over when it is sealed is placed on the outer surface of the back substrate 4, and a cap-shaped relatively light weight 16 is placed on the top of the exhaust thin tube 13. The jig 15 includes a cylindrical portion 18 having a flange 17 and a tripod portion 19 projecting downward from the flange 17. The back substrate 4
In addition, crystalline low melting point frit is used for the frame-like low melting point frit layers 20a and 20b provided on and superimposed on each inner surface of the front substrate 2. Further, the front substrate 2 and the rear substrate 4 are sealed with each other by an appropriate number of clips 21 and backing plates 22 and weights (not shown) as shown in FIG. If the exhaust thin tube 13 has a sufficient weight, the weight 16 can be omitted. If the cap 10 has a small weight, an appropriate weight is added to the cap 10.

本例では、ゲッタ12を収容するガラス製帽状体10と背
面基板4との間に介在させる環状のフリット層23に非晶
質の低融点フリットを用いるが、これに代えて結晶質の
低融点フリットを用いてもよい。この場合は、封着期間
中の帽状体10を、比較的重いウエイトまたはクリップで
もって背面基板4側へ強く抑え込む必要がある。また、
本発明の他の実施例では、環状の低融点フリット層23に
非晶質の低融点フリットを用い、その上に帽状体10が浮
上自在に積み重ねられる。そして、環状の低融点フリッ
ト層14に結晶質の低融点フリットが用いられ、その上に
排気用細管13が浮上不能に積み重ねられる。
In this example, an amorphous low melting point frit is used for the annular frit layer 23 interposed between the glass cap-shaped body 10 accommodating the getter 12 and the rear substrate 4, but instead of this, a crystalline low frit is used. A melting point frit may be used. In this case, it is necessary to strongly press the cap-like body 10 during the sealing period toward the rear substrate 4 with a relatively heavy weight or clip. Also,
In another embodiment of the present invention, an amorphous low melting point frit is used for the annular low melting point frit layer 23, and the cap-shaped body 10 is stacked on the frit layer 23 so as to float. Then, a crystalline low-melting-point frit is used for the annular low-melting-point frit layer 14, on which the exhaust thin tubes 13 are stacked so as not to float.

ところで、前述のようにして封着を終えた外囲器は、
炉外にとり出されて常温に近い温度になると、その管内
気圧はかなり低くなる。したがって、排気工程に入るべ
く排気用細管13の先端部を大気中で切断すると、その瞬
間、外囲器内に空気が侵入する。
By the way, the envelope that has been sealed as described above,
When it is taken out of the furnace and reaches a temperature close to room temperature, the pressure in the pipe becomes considerably low. Therefore, when the distal end portion of the exhaust thin tube 13 is cut in the atmosphere to enter the exhaust process, air enters the envelope at that moment.

そこで、本発明では第3図に例示したような装置を用
いて、排気用細管13を不活性ガス雰囲気中で切断する。
すなわち、排気用細管13の先端部に切り傷24を図外のダ
イヤモンドカッタで形成したのち、無底容器25内のパイ
プ26に細管13の先端部を差し込む。容器25内には窒素ま
たはアルゴンからなる不活性ガスが、ガス管27を通じて
毎分約30リットルの量で送り込まれている。この状態で
プッシャ28を図示矢印の方向へ移動させてパイプ26に当
接させると、筒状体26は支軸29を支点にした動きをなし
て、細管13は切り傷24の位置で切断される。そして、外
囲器内に不活性ガスが吸入されるのであり、一旦吸入さ
れた不活性ガスは外囲器内にとどまる。
Therefore, in the present invention, the exhaust thin tube 13 is cut in an inert gas atmosphere using an apparatus as illustrated in FIG.
That is, after a cut 24 is formed at the distal end of the exhaust thin tube 13 with a diamond cutter (not shown), the distal end of the thin tube 13 is inserted into the pipe 26 in the bottomless container 25. An inert gas made of nitrogen or argon is fed into the container 25 through a gas pipe 27 at a rate of about 30 liters per minute. In this state, when the pusher 28 is moved in the direction of the arrow shown in the drawing to make contact with the pipe 26, the tubular body 26 moves around the support shaft 29, and the thin tube 13 is cut at the position of the cut 24. . Then, the inert gas is sucked into the envelope, and the inert gas once sucked remains in the envelope.

発明の効果 以上のように、本発明によると、封着工程において熱
膨張した外囲器内気体が封着部に欠陥を生じさせる危険
や、密封状態となった外囲器が外気を吸い込むことによ
り生じる表示機能低下や、排気用細管の先端部が切断さ
れた後の外囲器内に空気が入り込むことによる表示機能
低下を完全になくすことができる。
Advantageous Effects of the Invention As described above, according to the present invention, there is a danger that the gas in the envelope thermally expanded in the sealing step may cause a defect in the sealing portion, and the sealed envelope may suck in the outside air. , And a decrease in display function due to air entering the envelope after the distal end of the exhaust tubule has been cut can be completely eliminated.

【図面の簡単な説明】[Brief description of the drawings]

第1図は本発明の製造方法によって製造されるPDPの封
着時の側断面図、第2図は同封着時の要部斜視図、第3
図は同封着後に排気用細管の先端部を切断する工程の側
断面図、第4図は従来のPDPの側断面図である。 2……前面基板、4……背面基板、6,9……通孔、10…
…帽状体、13……排気用細管、14,23……低融点フリッ
ト層、15……治具、20a,20b……低融点フリット層、24
……切り傷、27……ガス管。
FIG. 1 is a side sectional view of a PDP manufactured by the manufacturing method of the present invention at the time of sealing, FIG.
FIG. 4 is a side sectional view of a step of cutting the distal end portion of the exhaust thin tube after the sealing, and FIG. 4 is a side sectional view of a conventional PDP. 2 ... front substrate, 4 ... rear substrate, 6, 9 ... through-hole, 10 ...
… Cap-like body, 13… Exhaust tubing, 14,23 …… Low melting frit layer, 15… Jig, 20a, 20b …… Low melting frit layer, 24
... cuts, 27 ... gas pipes.

Claims (1)

(57)【特許請求の範囲】(57) [Claims] 【請求項1】少なくとも1個の通孔を有する背面基板と
透明な前面基板とを、それぞれの内面上に付設した枠状
の結晶質低融点フリット層を介し重ね合わせて締め付け
る一方、先端部で閉塞した排気用細管およびゲッタ収容
用帽状体の少なくとも一方を前記背面基板の外面上に、
環状の非晶質低融点フリット層を介し浮上自在に積み重
ねて前記通孔を覆い、前記結晶質低融点フリット層およ
び前記非晶質低融点フリット層を加熱溶融して気密な外
囲器を形成し、かつ、冷却後外囲器の前記排気用細管の
先端部を不活性ガス雰囲気中で切断することを特徴とす
る偏平型表示管の製造方法。
1. A back substrate having at least one through hole and a transparent front substrate are overlapped and fastened via a frame-shaped crystalline low-melting frit layer provided on the respective inner surfaces, and the front substrate is fastened at the tip. At least one of the closed exhaust thin tube and the getter housing cap-shaped body is provided on the outer surface of the back substrate,
An airtight envelope is formed by heating and melting the crystalline low-melting-point frit layer and the amorphous low-melting-point frit layer so as to cover the through-hole by floatingly stacking through an annular amorphous low-melting-point frit layer. And cutting the distal end of the exhaust thin tube of the envelope in an inert gas atmosphere after cooling.
JP63061087A 1988-03-15 1988-03-15 Manufacturing method of flat display tube Expired - Lifetime JP2781388B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP63061087A JP2781388B2 (en) 1988-03-15 1988-03-15 Manufacturing method of flat display tube

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP63061087A JP2781388B2 (en) 1988-03-15 1988-03-15 Manufacturing method of flat display tube

Publications (2)

Publication Number Publication Date
JPH01235125A JPH01235125A (en) 1989-09-20
JP2781388B2 true JP2781388B2 (en) 1998-07-30

Family

ID=13160966

Family Applications (1)

Application Number Title Priority Date Filing Date
JP63061087A Expired - Lifetime JP2781388B2 (en) 1988-03-15 1988-03-15 Manufacturing method of flat display tube

Country Status (1)

Country Link
JP (1) JP2781388B2 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6848964B1 (en) 1998-09-14 2005-02-01 Matsushita Electric Industrial Co., Ltd. Sealing method and apparatus for manufacturing high-performance gas discharge panel
JP2000215807A (en) * 1999-01-22 2000-08-04 Saes Getters Japan Co Ltd Manufacture of plate-like panel display device storing getter material
WO2007108116A1 (en) * 2006-03-22 2007-09-27 Fujitsu Hitachi Plasma Display Limited Plasma display panel, plasma display device, and process for producing plasma display panel
JP5123764B2 (en) * 2008-07-03 2013-01-23 日本放送協会 Manufacturing method of display panel

Also Published As

Publication number Publication date
JPH01235125A (en) 1989-09-20

Similar Documents

Publication Publication Date Title
KR20040053198A (en) Glass panel and method of manufacturing the glass panel
US4125390A (en) Method of vacuum-sealing vacuum articles
JP2781388B2 (en) Manufacturing method of flat display tube
JP2002083535A (en) Sealed container, its manufacturing method, and display device
JPH0465486B2 (en)
JP4180189B2 (en) Plasma display device manufacturing method and rear panel
US5587622A (en) Low pressure gas discharge lamps with low profile sealing cover plate
US6459198B1 (en) Seal and method of sealing devices such as displays
JPS63181248A (en) Manufacture of electron tube
GB2029084A (en) Constructing gas discharge displays
US5537001A (en) Flat vacuum chambers without pumping stem
JP2774748B2 (en) Metal vacuum double container and method of manufacturing the same
JPH01211827A (en) Manufacture of flat type indicator tube
JPH0210542B2 (en)
JPH0592136A (en) Adsorbent packing bag and production thereof
JPH0945243A (en) Vacuum airtight vessel and manufacture of it
JPS63284742A (en) Fluorescent character display tube
JPH061667B2 (en) Fluorescent display tube
JPH06196094A (en) Manufacture of vacuum display device
JPH0311524A (en) Method for vacuum-hermetic sealing fluorescent character display tube
JPH03254042A (en) Manufacture of discharge container
JPH1167092A (en) Manufacture of fluorescnet display tube
JPH04342940A (en) Vacuum envelope
US20110279030A1 (en) Plasma display panel and manufacturing method thereof
JPH0511535U (en) Crystal oscillator

Legal Events

Date Code Title Description
EXPY Cancellation because of completion of term