200535409 (1) 九、發明說明 【發明所屬之技術領域】 本發明係關於使尖鋒功率爲10MW以上之巨脈波振盪 、方式之雷射光安定地入射至光纖之雷射光入射光學裝置。 【先前技術】 傳統上，雷射剝蝕、雷射誘導螢光分析、或雷射擊等 Φ 時，係使用利用尖鋒功率爲數MW以上之巨脈波（GP)振盪 方式之固體雷射振盪器所得到之雷射光。 此種功率較大之雷射光之傳送，係利用例如以石英爲 材質之階變折射型光纖。 其次，以石英爲材質之光纖在連續振盪（CW)雷射光時 ，至數kW爲止都可傳送。然而，脈波期間爲數nsec程度之 短脈波雷射光且脈波能超過數十mJ之雷射光，尖鋒功率會 達到數MW以上。 ® 相對於連續振盪光之脈波能，短脈波雷射光之脈波能 大約爲100倍以上，且尖鋒功率密度亦爲極高之lfT1〜 l.OGW/cm2級。因此，因爲電子突崩現象或多光子吸收所 導致之損害，會使光纖被破壞而無法傳送雷射光。此外， k 有報告指出，石英（石英玻璃）材之脈波雷射光導致受損之 臨界値，在脈波期間約5nsec時約爲l〇〇GW/cm2(「LASER HANDBOOK」、雷射學會著、〇HMSHA、pp.463、473)。 因此’具有空間及時間之分布之雷射光，亦即短脈波 雷射光，利用光纖傳送時之實用限度，例如，以使脈波期 200535409 (2) 間51136(：、振盪頻率1〇1^之^:丫八0雷射光入射至芯徑爲 1mm之光纖時爲例來進行說明的話，脈波能爲30〜40mJ程 度，亦即，尖鋒功率爲6〜8MW(相對於芯徑之尖鋒功率密 〜度爲 0.76 〜1 .OGW/cm2)。 > 因此，以現狀而言，欲傳送10MW以上之短脈波雷射 光時，光纖之內部會受損，實質上，無法傳送雷射光。亦 即，以利用光纖實施傳送爲前提之固體雷射振盪器之雷射 # 光，主要係連續振盪（CW)雷射光，尖鋒功率超過數MW之 短脈波雷射光，難以利用光纖來進行傳送。 此外，爲了利用光纖傳送雷射光而使雷射光入射至光 纖之實例，有報告指出應使雷射光及光纖獲得空間之匹配 。此時，爲了使雷射光對光纖之入射口徑限制於光纖之芯 徑以內且限制於光纖之數値孔徑NA以內，而有使雷射光 聚光並入射至光纖之入射端面之報告（「雷射加工技術」 、川澄博通著、日刊工業新聞社、pp.34〜37)。 ® 然而，實施高尖鋒功率之雷射光之聚光並入射至光纖 ，在光纖之內部會發生雷射光之部份收斂，光纖之特定部 份之功率密度會較高，而使光纖之內部受損。此外，亦有 以較淺之雷射光之聚光程度來防止光纖內部發生雷射光收 ~ 斂之方法，然而，尖鋒功率超過數M W時，難以完全防止 '光纖內部之雷射光收斂。 此外，非專利文獻2之報告指出，光纖內部之雷射光 收斂導致光纖受損之原因，係因爲尖鋒功率較高之雷射光 之電場強度亦較高，光纖之石英材之部份折射率會因爲較 -6 - 200535409 (3) 強之電場而改變，而發生一種透鏡效果所導致之自聚焦。 此外，爲了傳送尖鋒功率超過10MW之雷射光，可以 採用以下之方法，亦即，將經過放大之雷射光入射至陣列 狀分裂透鏡進行空間之數十分割後，再利用配設於陣列後 方之聚光透鏡使全部分割數入射至光纖。 爲了傳送尖鋒功率超過1 〇 M W之雷射光，將經過放大 之雷射光入射至陣列狀分裂透鏡進行空間之數十分割後， # 再利用配設於陣列後方之聚光透鏡使全部分割數入射至光 纖之方法，因爲陣列狀配列之分裂透鏡可製造之尺寸爲 2mm程度，例如，爲了得到81分割（ = 9X9)之分割數，必須 使2mm四方之凸透鏡成爲縱橫9個並列之18mmX 18mm之分 裂透鏡群（蠅眼透鏡）。然而，分裂透鏡群有十分昂貴之問 題，亦即，蠅眼透鏡有十分昂貴之問題。 此外，例如，利用縱向倂列9個寬度2mmX長度18mm 之寬度2mm方向具有曲率之柱面透鏡的橫向分裂透鏡群、 • 及橫向倂列9個同樣透鏡之縱向分裂透鏡群之2個透鏡群組 成分割數81 ( = 9X9)，亦可獲得與上述蠅眼透鏡相同之效果 。然而，透鏡之成本雖然可降低少許，卻有構件點數及用 以保持之構造構件等增加而使總成本增加之問題。 此外，使用蠅眼透鏡時，即使透鏡之大小爲分割數 8 1=9X9之18mm四方，雷射光之剖面尺寸（束徑）必須放大 爲一邊爲1 8 m m之正方形之對角線之約2 6 m m。 此外，使用蠅眼透鏡時，除了上述之成本增大以外， 因爲各透鏡之境界部份之反射損失所造成之影響，而有傳 200535409 (4) 送效率降低1 〇〜2 0 %程度之問題、以及必須調整 之位置之問題。 【發明內容】 本發明之目的，係以較便宜之成本提供可在 受損的情形下傳送雷射光，且傳送效率不會降低 行複雜調整之將尖鋒功率大於10MW之巨脈波振 ^ 固體雷射振盪器之雷射光入射至光纖之入射端面 入射光學裝置。 本發明係用以將尖鋒功率大於1 0 M W之巨脈 式的固體雷射振盪器之雷射光，入射至光纖之入 雷射光入射光學裝置，具有：使從前述固體雷射 雷射光聚光的聚光透鏡；及於較此聚光透鏡所成 聚光點後方之特定位置，設置光纖之入射端面， 射光呈發散性入射至光纖之入射端面的光纖位置 # ;且，前述光纖係含有石英之材質，對於芯徑之 爲0.03 5〜0.1倍，數値孔徑ΝΑ爲0.06〜0.22之階 者。 其次，採用含有石英之材質，對於芯徑之纖 ‘ 0.03 5〜0.1倍，數値孔徑ΝΑ爲0.06〜0.22之階變 •纖，使尖鋒功率超過10MW之巨脈波振盪方式之 振盪器之雷射光呈發散性入射至該光纖之入射端 光纖不會受損的情形下傳送雷射光。 蠅眼透鏡 光纖不會 亦無需進 盪方式的 之雷射光 波振盪方 射端面之 振盪器之 雷身寸光之 使前述雷 調整機構 纖殻厚度 變折射型 殻厚度爲 折射型光 固體雷射 面，可在 200535409 (5) 【實施方式】 以下，參照圖面，針對本發明之實施形態進行說明。 第1圖至第9圖係說明雷射光入射光學裝置之實施形態 〇 如第1圖所示，雷射光入射光學裝置1 1係將尖鋒功率 大於10MW之巨脈波振盪方式之固體雷射振盪器（雷射裝置 )111所產生之脈波雷射光，射入特定之芯徑及纖殻厚度之 # 光纖101之入射端面102，可獲得光纖101不會受損且只有 少許損失之入射者。 雷射光入射光學裝置Π具有：用以實施固體雷射振盪 器1 1 1提供之剖面束徑爲特定大小之雷射光L之聚光之聚光 透鏡1 3 ;及用以使聚光透鏡1 3及光纖1 0 1之入射端面1 02間 之距離維持於一定距離之光纖位置調整機構1 5。 聚光透鏡1 3係便宜且容易取得之凸透鏡，只要可承受 固體雷射振盪器1Π射出之雷射光1入射時所產生之熱之材 # 質及形狀，並無特別限制。此外’必要時’聚光透鏡1 3亦 可以爲由2片薄透鏡組合而成之合成透鏡。 光纖位置調整機構1 5具有：用以保持聚光透鏡1 3之聚 光透鏡保持部1 6、保持光纖1 〇 1之光纖保持部1 7、用以調 > 整相對於聚光透鏡保持部1 6所保持之聚光透鏡1 3之光纖 • 1 0 1之入射端面1 〇 2之相對間隔之調整部1 8。該調整部1 8可 將光纖1 01調整於使光纖1 0 1之入射端面1 0 2位於聚光透鏡 13之焦點位置，亦即，將光纖1 0〗調整於使光纖1 ο 1之入射 端面1 0 2位於聚光點A後方之特定距離之位置。此外，調整 200535409 (6) 部1 8可利用手動、或由馬達及齒輪機構等所構成之移動機 構等，而任意設定與光纖保持部1 7之聚光透鏡保持部1 6間 之距離。 此外，使光纖101之入射端面102位於聚光透鏡13之焦 點位置，亦即，使光纖101之入射端面1〇2位於聚光點八後 方特定距離之特定位置，可使入射至光纖101之入射端面 102之雷射光L呈現發散性。亦即，使光纖101之入射端面 • 1 02及聚光透鏡1 3間之距離獲得最佳化，而使入射至光纖 1 0 1之入射端面1 〇 2之雷射光L呈現發散性，入射至光纖1 〇 1 內之雷射光L會在光纖1 0 1內之特定位置呈現收斂，結果， 光纖101之特定位置之尖鋒功率之密度會昇高’而可抑止 光纖1 0 1之受損。 此外，聚光透鏡13及光纖101之入射端面102間之位置 關係的最佳化，在雷射光L之尖鋒功率密度爲特定大小時 ，例如，超過l〇〇GW/Cm2，可防止聚光透鏡13之聚光點A Φ 所發生之空氣分解之影響而使雷射光L無法安定傳送、及 發生空氣分解而產生之電漿到達光纖丨〇丨之入射端面102而 使光纖1 〇 1之入射端面1 02受損之情形。 參照第2圖至第4圖進行具體4說明，然而，聚光透鏡 ^ 13之用以實施雷射光L聚光之聚光點A及光纖101之入射端 •面102間之距離爲例如1〜10數mm。 亦即，若雷射光L之脈波能爲E[Wt]、雷射光L之脈波 期間爲t [ s e c ]、發生空氣分解之臨界値之尖鋒功率密度爲 Pth[Wt/cm2]、利用聚光透鏡1 3聚光之雷射光L之聚光徑（半 -10- 200535409 (7) 徑）爲ω [mm]，則聚光徑Μ如下式所示 ω=^ [E/ (P thXnXt)] …（ 此外，若傳送之雷射光L之尖鋒功率爲P[W]，貝1HD式 可以下式表示° …（2) 〇) [ P / (P t h X π )]200535409 (1) IX. Description of the invention [Technical field to which the invention belongs] The present invention relates to a laser light incident optical device for stably incident laser light having a sharp pulse power of 10 MW or more on a fiber and stably incident on an optical fiber. [Prior art] Traditionally, laser ablation, laser-induced fluorescence analysis, or laser firing Φ uses a solid-state laser oscillator that uses a giant pulse wave (GP) oscillation method with a peak power of several MW or more. The resulting laser light. The transmission of such high-power laser light is, for example, using a step-varying refractive optical fiber made of quartz. Secondly, the optical fiber made of quartz can transmit up to several kW during continuous oscillation (CW) laser light. However, when the pulse duration is short pulse laser light with a duration of several nsec and the pulse energy exceeds tens of mJ of laser light, the peak power will reach several MW or more. ® Compared with the pulse energy of continuous oscillation light, the pulse energy of short pulse laser light is about 100 times and the peak power density is also extremely high lfT1 ~ l.OGW / cm2. Therefore, the damage caused by electron burst or multi-photon absorption can cause the optical fiber to be damaged and unable to transmit laser light. In addition, k has reported that the critical threshold of damage caused by pulsed laser light of quartz (quartz glass) material is about 100 GW / cm2 at about 5 nsec during the pulse period ("LASER HANDBOOK", by the Laser Society) , OHMSHA, pp.463, 473). Therefore, 'the laser light with spatial and temporal distribution, that is, short pulse laser light, is practically limited when transmitting using optical fiber, for example, to make the pulse wave period 200535409 (2) between 51136 (:, oscillation frequency 1〇1 ^ ^: Yaba0 laser light incident on an optical fiber with a core diameter of 1mm as an example to explain, the pulse wave energy is about 30 ~ 40mJ, that is, the peak power is 6 ~ 8MW (relative to the core diameter tip Frontal power density is 0.76 to 1.0GW / cm2). Therefore, in the current situation, if short-wave laser light of more than 10MW is to be transmitted, the inside of the optical fiber is damaged, and in essence, laser light cannot be transmitted. That is, the laser light of the solid laser oscillator based on the premise of using optical fiber for transmission is mainly continuous oscillation (CW) laser light, and the short pulse laser light with a peak power exceeding several MW is difficult to use optical fiber to In addition, in order to use the optical fiber to transmit the laser light and make the laser light incident on the optical fiber, there are reports that the laser light and the optical fiber should be matched in space. At this time, in order to limit the incident diameter of the laser light to the optical fiber to the optical fiber, Within core diameter and limited Within the optical fiber's numerical aperture NA, there are reports that condensed laser light and incident it on the incident end face of the optical fiber ("laser processing technology", by Kasumi Hirotsu, Nikkan Kogyo Shimbun, pp.34 ~ 37). However, when the laser light with high sharp power is collected and incident on the optical fiber, the laser light partially converges inside the optical fiber, and the power density of certain parts of the optical fiber will be higher, which will damage the internal part of the optical fiber. In addition, there is also a method of preventing the laser light from being condensed within the optical fiber by condensing the shallower laser light. However, when the peak power exceeds several MW, it is difficult to completely prevent the laser light from converging inside the optical fiber. The report of Non-Patent Document 2 pointed out that the cause of optical fiber damage caused by the convergence of laser light inside the fiber is because the electric field intensity of laser light with higher sharp power is also higher, and the refractive index of part of the quartz material of the optical fiber will be Compared with -6-200535409 (3) The strong electric field changes and self-focusing caused by a lens effect occurs. In addition, in order to transmit laser light with a peak power exceeding 10MW, the following can be used Method, that is, after the amplified laser light is incident on the array-like split lens to perform tens of divisions in the space, then the condenser lens arranged behind the array is used to make the entire division number incident on the optical fiber. 10 MW laser light, after the amplified laser light is incident on the array-like split lens to perform tens of divisions in the space, # the method of using the condenser lens arranged behind the array to make the entire division number incident on the optical fiber, because The array-shaped split lens can be manufactured to a size of about 2mm. For example, in order to obtain the number of divisions of 81 divisions (= 9X9), it is necessary to make a 2mm square convex lens into 9 parallel 18mmX 18mm split lens groups (fly-eye lens). ). However, the split lens group has a problem that it is very expensive, that is, the fly-eye lens has a problem that it is very expensive. In addition, for example, a horizontally split lens group of nine cylindrical lenses having a width of 2 mm × a length of 18 mm and a width of 2 mm in the direction of curvature, and two vertical lens groups of nine vertically split lens groups of the same lens in a horizontal queue With the number of divisions 81 (= 9X9), the same effect as that of the above-mentioned fly-eye lens can also be obtained. However, although the cost of the lens can be reduced a little, there is a problem that the number of component points and structural members to be held increases, which increases the total cost. In addition, when a fly-eye lens is used, even if the size of the lens is 18 mm square of the number of divisions 8 1 = 9X9, the cross-sectional size (beam diameter) of the laser light must be enlarged to about 2 6 of the diagonal of a square of 18 mm on one side. mm. In addition, when using a fly-eye lens, in addition to the above-mentioned increase in cost, due to the effect of the reflection loss of the boundary part of each lens, there is a problem that 200535409 (4) the transmission efficiency is reduced by 10 to 20%. , And the question of where to adjust. [Summary of the Invention] The purpose of the present invention is to provide a giant pulse wave with a sharp peak power greater than 10 MW, which can transmit laser light in a damaged condition at a relatively low cost without reducing transmission efficiency. ^ Solid The laser light of the laser oscillator is incident on the incident end face of the optical fiber and enters the optical device. The present invention is an optical device for condensing the laser light of a giant-pulse solid laser oscillator with a peak power of more than 10 MW into an optical fiber, and has the following features: condensing the laser light from the solid laser A condensing lens; and a specific position behind the condensing point formed by the condensing lens, an incident end face of the optical fiber is set, and the light is incident on the optical fiber position of the incident end face of the optical fiber with divergence #; and the aforementioned optical fiber contains quartz For the material, the core diameter is 0.03 5 ~ 0.1 times, and the number of apertures NA is 0.06 ~ 0.22. Secondly, using quartz-containing material, for the fiber with a core diameter of '0.03 5 ~ 0.1 times, the number of apertures NA is a step change of 0.06 ~ 0.22, and the fiber has a sharp pulse power of more than 10MW. The laser light is transmitted to the incident end of the optical fiber in a divergent manner without the optical fiber being damaged. The fly-eye lens fiber does not and does not need to oscillate the laser light wave oscillation. The laser body of the square-end face of the oscillator has the light of the body. The thickness of the above-mentioned laser adjustment mechanism is changed to the refractive type. The thickness of the case is a refracting optical solid laser surface. , 200535409 (5) [Embodiment] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Figures 1 to 9 illustrate the implementation of the laser light incident optical device. As shown in Figure 1, the laser light incident optical device 11 is a solid laser oscillation that uses a giant pulse wave method with a peak power greater than 10MW. The pulsed laser light generated by the laser device (laser device) 111 is incident on the incident end face 102 of the optical fiber 101 with a specific core diameter and fiber shell thickness, so that an incident person who does not damage the optical fiber 101 and has only a small loss can be obtained. The laser light incident optical device Π has a condenser lens 1 3 for implementing the focusing of the laser light L with a cross-section beam diameter provided by the solid-state laser oscillator 1 1 1; and a condenser lens 1 3 And an optical fiber position adjusting mechanism 15 which maintains a distance between the incident end surface 102 of the optical fiber 101 at a certain distance. The condenser lens 13 is a cheap and easy-to-obtain convex lens, as long as it can withstand the quality and shape of the material # and the shape of the heat generated when the laser light 1 emitted from the solid-state laser oscillator 1Π is incident. In addition, when necessary, the condenser lens 1 3 may be a composite lens composed of two thin lenses. The optical fiber position adjusting mechanism 15 includes: a condenser lens holding portion 16 for holding the condenser lens 13; an optical fiber holding portion 17 for holding the optical fiber 10; and an adjustment and adjustment unit for the condenser lens holding portion 1 6 The optical fiber of the condenser lens 13 held by 1 • The adjusting portion 18 of the relative spacing of the incident end face 1 0 2 of 1 0 1. The adjusting part 18 can adjust the optical fiber 1 01 so that the incident end surface 1 2 of the optical fiber 1 0 1 is located at the focal position of the condenser lens 13, that is, adjust the optical fiber 1 0 to the incident end surface of the optical fiber 1 ο 1. 1 0 2 is located at a specific distance behind the spot A. In addition, the adjustment of 200535409 (6) section 18 can be performed manually or using a moving mechanism composed of a motor, a gear mechanism, etc., and the distance from the condenser lens holding section 16 of the fiber holding section 17 can be arbitrarily set. In addition, the incident end face 102 of the optical fiber 101 is located at the focal position of the condenser lens 13, that is, the incident end face 102 of the optical fiber 101 is located at a specific position at a specific distance behind the focusing point eight. The laser light L on the end surface 102 is divergent. That is, the distance between the incident end face of the optical fiber 101 and the condenser lens 13 is optimized, and the laser light L incident on the incident end face 1 of the optical fiber 101 is divergent and incident on The laser light L in the optical fiber 101 will converge at a specific position in the optical fiber 101, and as a result, the density of the sharp power of the specific position of the optical fiber 101 will increase, and the damage of the optical fiber 101 can be suppressed. In addition, when the positional relationship between the condenser lens 13 and the incident end face 102 of the optical fiber 101 is optimized, when the peak power density of the laser light L is a specific size, for example, exceeding 100 GW / Cm2, the light can be prevented from being condensed. The condensing point A Φ of the lens 13 is affected by the air decomposition, so that the laser light L cannot be transmitted stably, and the plasma generated by the air decomposition reaches the incident end surface 102 of the optical fiber 丨 〇 丨 and makes the optical fiber 〇1 incident. Damage to the end surface 02. Specific explanation will be made with reference to FIGS. 2 to 4. However, the distance between the focusing point A of the condensing lens ^ 13 for laser light condensing and the incidence end surface 102 of the optical fiber 101 is, for example, 1 to 10 several mm. That is, if the pulse wave energy of the laser light L is E [Wt], the pulse wave period of the laser light L is t [sec], and the peak power density of the critical radon where air decomposition occurs is Pth [Wt / cm2]. Condensing lens 1 3 The condensing diameter (half -10- 200535409 (7) diameter) of the condensing laser light L is ω [mm], then the condensing diameter M is as follows: ω = ^ [E / (P thXnXt )]… (In addition, if the transmitted peak power of the laser light L is P [W], the Bay 1HD formula can be expressed by the following formula: ° (2) 〇) [P / (P th X π)]
另一方面，若入射至聚光透鏡13之雷射光[之發散角 爲Θ!(半角mad]、聚光透鏡13之焦點距離爲f[mm]，則聚 光徑（半徑）^如下式所示。 此外，若雷射光L之剖面束徑（口徑）爲r(半徑）[mm]、 固體雷射振盪器Π1至聚光透鏡13之距離爲Dl[mm] ’則可 利用聚光透鏡13之焦點距離f[mm]及入射至聚光透鏡13之 雷射光L之發散角0!(半角）利用下式求取聚光透鏡13聚光之 雷射光L之聚光角（亦即，聚光透鏡13聚光之雷射光L入射 至光纖101時之入射角）θ2(半角）[rad]。 θ2 = -τ/ί+ (l-D./f) Χθχ …（4) 因此’利用（2)〜（4)式，透鏡焦點距離f、雷射口徑（ 剖面束徑）r、入射至光纖101之雷射光L之入射角θ2、固體 雷射振盪器111至聚光透鏡13之距離Dl、雷射光L之尖鋒功 率P、以及發生空氣分解之臨界値之尖鋒功率密度Pth具有 下式之關係。 f = [~ (r-α) {(r-a) 2-4X01XaXD1}] / (2X0 2) :[p/ (p t h X π)] …（5) 利用（5)式可求取聚光透鏡13之聚光點A不會發生空氣 -11 - 200535409 (8) 分解之聚光透鏡1 3之焦點距離f。亦即’因爲可利用（5 )式 求取聚光透鏡13之焦點距離f且可以利用（3)式及（1)式或（2) 式求取入射聚光透鏡13之雷射光L之入射角（亦即’發散角 )θ ;，故只要將入射至聚光透鏡1 3之雷射光L之入射角設定 成Θ !，則可在不會發生空氣分解之情形下’使雷射光L有 效率地入射光纖1 0 1。 其實例上，例如，雷射光L之口徑（直徑）爲2〜1 3111111之 % 範圍、聚光透鏡1 3及固體雷射振盪器1 1 1間之距離在1 〇〜 5 00mm之範圍變化時，可利用之聚光透鏡13之焦點距離f之 計算結果如第3圖所示，入射至聚光透鏡1 3之雷射光L之入 射角（發散角）eii計算結果如第4圖所示。 例如，若雷射光L之口徑爲r = 3mm(直徑6mm)、固體雷 射振盪器111至聚光透鏡13之距離0!爲D! = 100mm、從聚光 透鏡13入射至光纖101之雷射光L之入射角（聚光角）爲 02 = 〇.15rad、尖鋒功率爲P = 20MW、發生空氣分解之臨界値 •之尖鋒功率密度爲Pth=100GW/cm2’可求取聚光透鏡13之 焦點距離f及入射至聚光透鏡1 3之雷射光之入射角㊀1分別 爲 f=24.9mm、ei=3.2mrad(全角爲 6.4mrad)。 例如，將依據實測設定之聚光透鏡1 3之焦點距離f代 入（4)式，必須在光纖101之入射角θ2大小不超過雷射光L入 射之光纖1〇1之ΝΑ之範圍，設定聚光透鏡13之焦點距離f( 參照第3圖）。 亦即，第3圖係圖示改變入射至光纖1 0 1之雷射光L之 聚光角（對光纖101之入射角）θ2時發生空氣分解之聚光透鏡 -12- 200535409 (9) 1 3之焦點位置，然而，改變雷射光L之口徑（剖面束徑）及 聚光透鏡13之設置位置’結果，下限値爲〇.〇6rad程度。 然而，因爲雷射光L之質（空間分佈及波前等）及聚光 透鏡1 3之光行差之影響等，有時實際聚光徑會大於理想聚 光徑。 此時，應使以（2)式求取之不會發生空氣分解之聚光徑 、及實際之聚光徑相等爲止，縮短聚光透鏡1 3之焦點距離 φ f，並放大雷射光L入射至光纖101時之數値孔徑NA(參照第 4圖）。此外，由雷射光L入射至光纖101時之數値孔徑NA、 及對適合發散入射方式之聚光透鏡1 3之入射角Θ !之關係’ 入射至光纖1 〇 1之雷射光L之入射角θ2之下限値應大於 0 · 0 6 r a d。 此外，聚光透鏡1 3之聚光點A及光纖1 0 1之設置位置（ 入射端面102之位置）方面，若聚光點A之聚光徑（半徑）爲 ω [mm]、聚光點A及光纖101之入射端面102間之距離爲 # Lf[mm]、雷射光L入射至光纖101之芯時之剖面束徑（亦即 ，入射徑）爲Wi(直徑）[mm]、雷射光L入射至光纖1〇1時之 入射角爲θ2(半角）[rad]，則可以下式表示。 L f = (Wi —2 ω) / (2 X t a η Θ 2)…（6) ~ 利用（6)式，將聚光透鏡13之焦點位置（聚光點A)、及 〜光纖101之入射端面102間之距離Lf設定成例如0.25〜16mm 。具體而言，若入射至光纖101之芯之雷射光L之入射徑之 最小値爲例如42 0 μηα (利用光纖101傳送之雷射光L之功率’ 亦即，依據能量或尖鋒功率而決定之芯徑之最小値）’此 -13- 200535409 (10) 外，若最大値爲例如容易取得之光纖101之最大芯徑 1500μιη 之 90% 之 1350μιη，且 Wi = 420 〜1350μηι、 ω = 100μιη (尖鋒功率30MW、發生空氣分解之臨界値 100GW/cm2之最小聚光徑）、= 〜0.22rad(如後面所述 )，計算適當之Lf範圍，則Lf之範圍爲如上面所述之〇·25〜 1 6 m m之範圍。 實用上，光纖101之入射端面102之可設定之最小距離 φ 爲1mm，聚光點A至光纖1〇1之入射端面1〇2之距離設定成Ϊ 〜16mm之範圍。然而，距離Lf若爲必要以上，則未入射 至光纖101之雷射光L亦增多，故其上限値應爲例如 程度。 聚光透鏡13及光纖101之入射端面1〇2間之距離Lf，最 好依據實際組合調整結果，而大致爲1 ·5〜5mm之範圍。 其次，從光纖101之芯徑及纖殻層之厚度，針對可入 射至光纖之雷射光L之強度進行說明。 ^ 如上面說明所示，使利用巨脈波振盪方式所得到之尖 鋒功率超過數MW(尖鋒功率密度爲1CT1〜l.OGW/cm2)之雷 射光L入射至光纖1 0 1時，光纖1 〇 1會受損而無法傳送雷射 光L。 ‘因此，若只利用以第1圖、第2圖至第4圖進行說明之 、聚光透鏡13及光纖101之入射端面102間之距離Lf、雷射光 L入射至聚光透鏡13時之入射角Θ!、以及聚光透鏡13聚光 之雷射光L入射至光纖101之入射端面102時之聚光角θ2， 則光纖1 〇 1可能受損。 -14- 200535409 (11) 以下，針對適當之光纖1 01之構造特徵及雷射光L之傳 送特性進行說明。 第5圖係實驗結果，係使脈波期間爲5 n s e c、雷射光L 之口徑（剖面束徑）爲700 μηι之雷射光L，利用第2圖進行說 明之發散入射方式及一般收斂入射方式，以入射角〇.〇2rad 入射至芯徑爲ΙΟΟΟμηι、纖殼層厚度爲50μιιι '數値孔徑ΝΑ 爲0.2之光纖101之實驗結果。 Φ 由第5圖可知，收斂入射方式時，傳送能量30mJ(尖鋒 功率6MW)會導致光纖101受損。相對於此，應用發散入射 方式時，確認傳送能量70m：T(尖鋒功率14MW)亦不會導致 光纖1 〇 1受損。 此外，光纖1 01之構造特徴上，係因爲芯材質之純度 較高而不易因爲雷射光L之能量而受損之如第6圖所示構造 之階變折射型石英材質。光纖1 〇 1係由芯1 〇3、形成於該芯 103周圍之纖殼104、以及形成於纖殼104周圍之被覆層105 •所構成。 此外，纖殻104之厚度方面，大於特定厚度時，彎曲 光纖1 〇 1時很容易因爲機械應力而導致破損，相反的，纖 殻104之層厚若太薄，則入射數MW電平之尖鋒功率之雷射 ~ 光！^時，從芯103漏出至纖殻104之雷射光L會導致光纖101 " 破損。 此外，纖殼1 04之厚度應小於芯1 03徑，例如，爲芯 1 〇 3徑之0 · 0 5〜0.1倍程度。因此，外漏至纖殼1 0 4之少許雷 射光L之尖鋒功率密度亦比芯103之部份高出10倍程度。此 - 15- 200535409 (12) 外，纖殼104及芯103之境界部之通常之雷射光L之傳送所 造成之繞射影響有點類似定波之存在，因爲部份尖鋒功率 會較高，故減少纖殻1 〇4之厚度時有其下限値。 第7圖係實驗結果，係改變纖殻104之厚度，使脈波期 間爲5nsec、口徑（剖面束徑）爲7 00μιη之雷射光L，利用第2 圖進行說明之發散入射方式，以入射角〇.〇2i*ad入射至芯徑 爲ΙΟΟΟμηι、數値孔徑NA爲0.2之光纖101之實驗結果。 • 由第7圖可知，隨著纖殼1〇4之厚度增加，可傳送較大 之能量。亦即，由第7圖得知，纖殼104之厚度爲20μηι時， 40mJ(尖鋒功率8MW)爲其界限，然而，若纖殻104之厚度 爲50μπι，則70mJ(尖鋒功率14MW)時，光纖101亦不會受損 〇 因此，由第7圖得知，爲了可以傳送尖鋒功率10MW以 上之雷射光L，纖殻104之厚度必須爲35 μιη以上。此外， 纖殼104之厚度若大於ΙΟΟμπι，則會變硬變脆，不易彎曲光 # 纖101，且彎曲半徑變大，故應爲100 μηι以下。 另一方面，因爲與利用光纖傳送之雷射功率密度 之關係，對芯徑設定著下限値，然而，芯徑之上限値如利 用第8圖進行之以下說明所示，例如，可以相對於入射之 雷射光L之口徑（剖面束徑）之比例來進行判斷。 第8圖係貫驗結果’係使纖威1 〇 4之厚度保持一定，並 使改變入射至光纖1 〇 1時之雷射光L 口徑（剖面束徑）之雷射 光L入射至改變芯徑之光纖1 0 1之實驗結果。 由第8圖可知，芯徑及入射之雷射光L之剖面束徑（口 -16- 200535409 (13) 徑）之間即使有差異，若纖殼1 04之厚度相同’則該範圍之 入射口徑可以傳送同樣爲10MW之尖鋒功率之雷射光L。 亦即，如第8圖所示，爲了傳送尖鋒功率10MW以上， 聚光徑必須爲420 μηι以上。因此’若考慮相對於聚光徑具 有8 0%程度之寬裕度，則芯徑應爲5 00μπι以上。 此外，如第9圖所示，依據改變雷射光L對光纖1 0 1之 入射角θ2利用發散入射方式使口徑（剖面束徑）爲70 Ομηι、 • 脈波期間爲5nSec之雷射光L入射至芯徑爲ΙΟΟΟμπι、纖殼 104厚度爲50μηι、數値孔徑ΝΑ爲0.2之光纖101時之實驗結 果，爲了使尖鋒功率爲15MW(能量換算爲80mJ)前後之雷 射光L以低損失之方式入射，必須爲0.06rad程度之入射角 θ2。此外，隨著入射角θ2之增大，可傳送之能量會愈大， 入射角02爲〇.12^(1程度時，可以傳送尖鋒功率爲20MW之 雷射光L。 另一方面，依據因爲芯103及纖殻104之境界部之繞射 • 而在光纖101內傳送入射至光纖101之雷射光L，光纖101存 在雷射光L入射時之數値孔徑Ν Α之上限。亦即，光纖1 0 1 之數値孔徑N A若太小，則發散入射方式時，對光纖1 01之 入射角Θ 2會變小而無法得到充分之效果。因此，如前面之 說明所示，入射至光纖101之雷射光L在光纖101之內部之 k 特定位置會發生收斂，而導致光纖101受損。 此外，光纖1 〇 1之數値孔徑NA若較大，則從光纖1 0 1 射出之雷射光L之角度會增大，故以使雷射光L以特定剖面 束徑照射對象物爲目的所使用之光學系亦會增大。例如， -17- 200535409 (14) 使用折射率η爲1 . 5程度之玻璃材料所構成之1片之平凸On the other hand, if the laser light incident on the condenser lens 13 [the divergence angle is Θ! (Half angle mad) and the focal distance of the condenser lens 13 is f [mm], the condensing diameter (radius) ^ is as follows: In addition, if the cross-section beam diameter (aperture) of the laser light L is r (radius) [mm], and the distance from the solid-state laser oscillator Π1 to the condenser lens 13 is Dl [mm] ', the condenser lens 13 can be used. The focal distance f [mm] and the divergence angle of the laser light L incident on the condenser lens 13 is 0! (Half angle) The following formula is used to find the condensing angle of the laser light L condensed by the condenser lens 13 (ie, the condenser angle) Incident angle when the laser light L condensed by the optical lens 13 is incident on the optical fiber 101) θ2 (half angle) [rad]. Θ2 = -τ / ί + (lD./f) χθχ… (4) Therefore, 'use (2) Equation (4), the lens focal length f, the laser aperture (section beam diameter) r, the incident angle θ of the laser light L incident on the optical fiber 101, the distance Dl from the solid laser oscillator 111 to the condenser lens 13, The peak power P of the emitted light L and the peak power density Pth of the critical 发生 at which the air is decomposed have the following relationship: f = [~ (r-α) {(ra) 2-4X01XaXD1}] / (2X0 2) : [p / (pth X π)] … (5) Using the formula (5), it can be found that the focal point A of the condenser lens 13 does not cause air -11-200535409 (8) The focal distance f of the decomposed condenser lens 1 3, that is, 'because it can be used (5) can be used to find the focal distance f of the condenser lens 13 and the angle of incidence (ie, 'divergence') of the laser light L incident on the condenser lens 13 can be obtained by using formulas (3) and (1) or (2). Angle) θ; therefore, as long as the incident angle of the laser light L incident to the condenser lens 13 is set to Θ !, the laser light L can be efficiently incident on the optical fiber 10 without air decomposition. 1. In its example, for example, the aperture (diameter) of the laser light L is in the range of 2 to 1 3111111, and the distance between the condenser lens 13 and the solid-state laser oscillator 1 1 1 is in the range of 10 to 500 mm. When changing, the calculation result of the focal distance f of the available condenser lens 13 is shown in FIG. 3, and the incident angle (divergence angle) eii of the laser light L incident on the condenser lens 13 is calculated as shown in FIG. 4 For example, if the diameter of the laser light L is r = 3mm (diameter 6mm), and the distance from the solid-state laser oscillator 111 to the condenser lens 13 is 0! The incident angle (condensing angle) of the laser light L incident from the lens 13 to the optical fiber 101 is 02 = 0.15 rad, the peak power is P = 20 MW, and the critical point for air decomposition occurs. The peak power density is Pth = 100 GW / cm2 'can obtain the focal length f of the condenser lens 13 and the incident angle ㊀1 of the laser light incident on the condenser lens 13, which are f = 24.9mm and ei = 3.2mrad (the full angle is 6.4mrad). For example, if the focal distance f of the condenser lens 13 set according to the actual measurement is substituted into the formula (4), the concentration must be set in a range where the incident angle θ2 of the optical fiber 101 does not exceed the NA of the optical fiber 101 that the laser light L enters. The focal distance f of the lens 13 (see FIG. 3). That is, FIG. 3 illustrates a condenser lens that undergoes air decomposition when changing the condensing angle (incident angle to the optical fiber 101) θ2 of the laser light L incident on the optical fiber 1 0 1-12-200535409 (9) 1 3 However, as a result of changing the aperture (section beam diameter) of the laser light L and the setting position of the condenser lens 13, the lower limit 値 is about 0.06 rad. However, due to the quality of the laser light L (spatial distribution, wavefront, etc.) and the effect of the light aberration of the condenser lens 13, the actual light-condensing path may sometimes be larger than the ideal light-condensing path. At this time, the condensing path that is obtained by the formula (2) without air decomposition and the actual condensing path should be made equal, the focal distance φ f of the condenser lens 13 should be shortened, and the incident laser light L should be enlarged. Number of apertures NA to fiber 101 (see Figure 4). In addition, the relationship between the numerical aperture NA when the laser light L is incident on the optical fiber 101 and the angle of incidence Θ! Of the condenser lens 13 suitable for a divergent incidence method 'is the angle of incidence of the laser light L incident on the optical fiber 101. The lower limit of θ2 should be greater than 0 · 0 6 rad. In addition, regarding the position of the light-condensing point A of the condenser lens 13 and the position of the optical fiber 101 (the position of the incident end surface 102), if the light-condensing diameter (radius) of the light-condensing point A is ω [mm], the light-condensing point The distance between A and the incident end face 102 of the optical fiber 101 is # Lf [mm], and the cross-sectional beam diameter (that is, the incident diameter) of the laser light L incident on the core of the optical fiber 101 is Wi (diameter) [mm], the laser light When the incident angle of L to the optical fiber 101 is θ2 (half angle) [rad], it can be expressed by the following formula. L f = (Wi —2 ω) / (2 X ta η Θ 2) ... (6) ~ Using the formula (6), the focal position of the condenser lens 13 (condensing point A), and ~ the incidence of the optical fiber 101 The distance Lf between the end faces 102 is set to, for example, 0.25 to 16 mm. Specifically, if the minimum incident diameter of the laser light L incident to the core of the optical fiber 101 is, for example, 42 0 μηα (the power of the laser light L transmitted by the optical fiber 101 ′, that is, determined based on energy or sharp power The smallest core diameter 値) 'this-13- 200535409 (10) In addition, if the maximum 値 is, for example, 1350 μm which is 90% of the maximum core diameter of 1500 μm of the easily available fiber 101, and Wi = 420 to 1350 μm, ω = 100 μm (tip The frontal power is 30MW, the critical concentration of air decomposition (minimum condensing diameter of 100GW / cm2), = ~ 0.22rad (as described later), calculate the appropriate Lf range, then the range of Lf is 0.25 as described above. ~ 16 mm range. Practically, the settable minimum distance φ of the incident end face 102 of the optical fiber 101 is 1 mm, and the distance from the light collecting point A to the incident end face 102 of the optical fiber 101 is set to a range of Ϊ to 16 mm. However, if the distance Lf is more than necessary, the laser light L not incident on the optical fiber 101 also increases, so the upper limit 値 should be, for example, a degree. The distance Lf between the condenser lens 13 and the incident end surface 102 of the optical fiber 101 is preferably adjusted in accordance with the actual combination, and is approximately in the range of 1.5 to 5 mm. Next, from the core diameter of the optical fiber 101 and the thickness of the fiber shell layer, the intensity of the laser light L that can be incident on the optical fiber will be described. ^ As shown above, when the laser light L with a peak power obtained by the giant pulse wave oscillation method exceeding several MW (the power density of the peak is 1CT1 to 1.0GW / cm2) is incident on the optical fiber 101, the optical fiber 〇1 is damaged and cannot transmit the laser light L. 'Therefore, if only the distance Lf between the condenser lens 13 and the incident end face 102 of the optical fiber 101 and the incident light of the laser light L incident on the condenser lens 13 are described using FIG. 1, FIG. 2 to FIG. 4, and FIG. Angle Θ! And the condensing angle θ2 when the laser light L condensed by the condenser lens 13 is incident on the incident end face 102 of the optical fiber 101, the optical fiber 1 〇1 may be damaged. -14- 200535409 (11) The structure characteristics of the appropriate optical fiber 101 and the transmission characteristics of the laser light L will be described below. Figure 5 shows the experimental results. The laser light L with a pulse period of 5 nsec and a laser beam L diameter (section beam diameter) of 700 μηι is described using the divergent incidence method and the general convergent incidence method described in FIG. 2. An experimental result of an optical fiber 101 having a core diameter of 100 μm and a fiber shell thickness of 50 μm and a number of apertures NA of 0.2 at an incidence angle of 0.02 rad. Φ As shown in Figure 5, in the convergent incidence method, the transmission of 30mJ of energy (6MW of sharp power) will cause damage to the optical fiber 101. In contrast, when the divergent incidence method is applied, it is confirmed that the transmission energy of 70m: T (14MW of sharp power) will not cause damage to the optical fiber 101. In addition, the structure of the optical fiber 101 is a step-change refractive quartz material of the structure shown in FIG. 6 because the core material has a high purity and is not easily damaged by the energy of the laser light L. The optical fiber 101 is composed of a core 103, a fiber case 104 formed around the core 103, and a covering layer 105 formed around the fiber case 104. In addition, when the thickness of the fiber housing 104 is greater than a specific thickness, it is easy to cause damage due to mechanical stress when bending the optical fiber 101. Conversely, if the layer thickness of the fiber housing 104 is too thin, the number of incident MW levels is sharp. Laser of Frontal Power ~ Light! At this time, the laser light L leaking from the core 103 to the fiber housing 104 will cause the optical fiber 101 to be damaged. In addition, the thickness of the fiber shell 104 should be smaller than the diameter of the core 103, for example, about 0.5 to 0.1 times the diameter of the core 103. Therefore, the tip power density of a small amount of laser light L leaking out to the fiber housing 104 is also about 10 times higher than that of the core 103 portion. This-15- 200535409 (12) In addition, the diffraction effect caused by the normal laser light L transmission in the boundary part of the fiber casing 104 and core 103 is somewhat similar to the existence of a fixed wave, because some of the sharp power will be higher. Therefore, there is a lower limit when reducing the thickness of the fiber shell 104. Fig. 7 shows the experimental results. The thickness of the fiber cover 104 is changed so that the laser light period L is 5 nsec and the aperture (profile beam diameter) is 700 μm. The divergent incidence method described in Fig. 2 is used. 〇2i * ad was incident on an optical fiber 101 having a core diameter of 100 μm and a numerical aperture of NA of 0.2. • As shown in Figure 7, as the thickness of the fiber case 104 increases, a larger amount of energy can be transmitted. That is, it is known from FIG. 7 that when the thickness of the fiber shell 104 is 20 μm, 40 mJ (tip power 8MW) is the limit. However, if the thickness of the fiber shell 104 is 50 μm, then 70 mJ (tip power 14 MW) The optical fiber 101 will not be damaged. Therefore, according to FIG. 7, in order to transmit the laser light L with a peak power of 10MW or more, the thickness of the fiber housing 104 must be 35 μm or more. In addition, if the thickness of the fiber shell 104 is greater than 100 μm, it will become hard and brittle, and it is difficult to bend the light # fiber 101, and the bending radius becomes large, so it should be 100 μm or less. On the other hand, the lower limit of the core diameter is set because of the relationship with the laser power density transmitted by the optical fiber. However, the upper limit of the core diameter is as shown in the following description using FIG. The ratio of the aperture (section beam diameter) of the laser light L is determined. Figure 8 shows the results of the test. 'It keeps the thickness of Fibre 1 04 constant and changes the laser light L diameter (section beam diameter) of the laser light L when incident on the optical fiber 101. Experimental results of optical fiber 101. It can be seen from FIG. 8 that even if there is a difference between the core diameter and the cross-sectional beam diameter of the incident laser light L (diameter-16-200535409 (13) diameter), if the thickness of the fiber shell 104 is the same, then the incident diameter in this range It can transmit the laser light L with a sharp power of 10MW. That is, as shown in FIG. 8, in order to transmit the peak power of 10 MW or more, the condensing path must be 420 μm or more. Therefore, if a margin of about 80% with respect to the condensing diameter is taken into consideration, the core diameter should be 500 μm or more. In addition, as shown in FIG. 9, according to changing the incident angle θ2 of the laser light L to the optical fiber 1 0 1, the aperture (profile beam diameter) is 70 Ομηι using a divergent incidence method. • The laser light L having a pulse period of 5 nSec is incident on The experimental results when the optical fiber 101 has a core diameter of 100 μm, a thickness of the fiber housing 104 of 50 μm, and an aperture diameter NA of 0.2 is 0.2, in order to make the laser power L before and after the peak power 15MW (80mJ energy conversion) incident with low loss , The incident angle θ2 must be about 0.06rad. In addition, as the incident angle θ2 increases, the energy that can be transmitted becomes larger. When the incident angle 02 is 0.12 ^ (1 degree, the laser light L with a sharp power of 20MW can be transmitted. On the other hand, based on the Diffraction at the boundary between the core 103 and the fiber casing 104. The laser light L incident on the fiber 101 is transmitted in the optical fiber 101, and the optical fiber 101 has an upper limit of the number of apertures N A when the laser light L is incident. That is, the optical fiber 1 If the number NA of 0 1 is too small, the incident angle θ 2 to the optical fiber 1 01 will be small when the divergent incidence method is used, so that the sufficient effect cannot be obtained. The laser light L converges at a specific position inside the optical fiber 101, resulting in damage to the optical fiber 101. In addition, if the number of the optical fiber 100 is larger, the laser light L emitted from the optical fiber 101 The angle will increase, so the optical system used to make the laser light L irradiate the object with a specific cross-section beam diameter will also increase. For example, -17- 200535409 (14) Use a refractive index η of about 1.5 One piece of flat convex made of glass material
透鏡，爲了以1以下之成像倍率使光纖1 0 1射出之雷射光L 聚光於對象物，從相對於透鏡曲率之透鏡口徑之製作極限 觀點而言，光纖1 之數値孔徑NA應爲NA与0.25rad以下。 此外，因爲纖殼之厚度大於一般光纖之纖殼厚度 ，若考慮前述光纖之機械強度（抗彎曲性）之降低’若芯For the lens, in order to condense the laser light L emitted from the optical fiber 101 to the object at an imaging magnification of 1 or less, from the viewpoint of the production limit of the lens aperture with respect to the curvature of the lens, the number of the optical fiber 1 and the aperture NA should be NA With 0.25rad or less. In addition, because the thickness of the fiber shell is greater than the thickness of the fiber shell of the general optical fiber, if the reduction of the mechanical strength (bending resistance) of the aforementioned fiber is considered ’
103之折射率爲n!、纖殼104之折射率爲n2，則數値孔徑NA φ 可以下式來規定。 ΝΑ=，[(ηι) 2- (η2) 2] 此外，爲了增大光纖1 0 1之數値孔徑ΝΑ，降低纖殻 104層之折射率的方法被廣泛利用，增加摻雜於纖殻1〇4層 之氟及硼之量會使其變脆而容易折斷。此外，若考慮利用 第7圖求取之纖殼1 〇 4厚度，則依據上述照射光學系所規定 之數値孔徑ΝΑ之上限應爲更低之大致0.221*ad。 因此，光纖101之數値孔徑NA之上限爲0.22。此外， # 因爲上限値會依據實際使用之光纖1 〇 1構造特徴及物性而 改變，故發散入射方式時，光纖1 〇 1可設定之數値孔徑N A 之上限不一定爲〇. 2 2，而爲依據光纖1 0 1構造特徴及物性 所規定之數値。 此外，由芯徑不受利用第3圖及第4圖說明之聚光透鏡 、 1 3之焦點位置及入射至光纖1 〇 1之雷射光L之入射角θ2、及 利用第8圖說明之光纖1 0 1之芯徑及入射至光纖1 0 1之雷射 光L之口徑（剖面束徑）之限制之實驗結果、以及利用第9圖 說明之能量傳送能力之確認結果，確認下限値只要與雷射 -18- 200535409 (15) 光L·之入射角θ2相等即可，故數値孔徑NA==0.〇6〜0.22rad 〇 由以上之說明可知，可以發散入射方式傳送2 0 M W (尖 鋒功率密度爲1 〇〇GW/cm2)程度之巨脈波振盪方式之雷射光 L之光纖1 〇 1，應介於 芯 103 徑爲 500 〜1500μηι、 纖殼104厚度爲35〜1〇〇μηι、 0 光纖101之數値孔徑ΝΑ爲〇·〇6〜0.22 之範圍。 此外，雷射光L入射至光纖1〇1之雷射光L之入射角θ2 ，應爲雷射光入射光學裝置1 1之構成所容許之範圍內之較 大角度。 由以上可知，爲了安定傳送尖鋒功率爲10MW以上之 脈波雷射光L、或尖鋒功率爲10MW以下之短脈波雷射光L ，例如，光纖101之數値孔徑ΝΑ = 0·2時，入射至光纖101之 # 雷射光L之入射角θ2應爲至0.2rad(光纖101之數値孔徑ΝΑ 之上限値）爲止之値。 其次’針對雷射光入射光學裝置1 1之具體實例進行說 明。 此外’以下所示之數値，係第9圖之前所說明之尖鋒 功率爲22MW之雷射光L之資料，例如，在以下之條件對階 變折射型之石英材質之光纖1 〇 1傳送利用巨脈波振盪方式 之Nd : YAG雷射振盪器之固體雷射振盪器U1之脈波期間 爲5nsec、脈波能爲n〇mJ(尖鋒功率爲22MW=n〇mJ/5nsec) -19- 200535409 (16) 、直徑6mm之雷射光L之結果。 對聚光透鏡13之入射角（入射發散角）ei = 1.8mrad(半 角） 雷射口徑（剖面束徑）r (半徑）=3 m m (直徑6 m m) 聚光透鏡1 3及固體雷射振盪器1 1 1之間隔D，6 00mm 聚光透鏡1 3之焦點距離f= 3 1 m m 光纖1 0 1之芯徑1 οοομη 瞻纖殻1 〇4之厚度5〇μηι 數値孔徑NA = 0.2rad 對光纖1〇1之雷射光L之入射角e2 = 〇.13rad(半角） 聚光透鏡13之聚光點A至光纖101之入射端面102之 距離Lf=2mm 對光纖1 〇1之雷射光L之入射口徑（剖面束徑）： 700μπα(直徑） 此外，利用上述數値以（4)式求取前面說明之對光纖 • 101之入射角θ2時，亦即，利用對聚光透鏡13之入射角（入 射發散角）θ! = 1.8 mr ad、聚光透鏡13及固體雷射振盪器111 之間隔D! =60 Omm、雷射入射口徑（剖面束徑）r (半徑）=3 mm 、以及聚光透鏡13之焦點距離f= 3 1mm以（4)式求取前面說 明之對光纖1〇1之入射角θ2時，入射角θ2 = 0.1 3 rad，確認本 發明可利用之光纖101之數値孔徑之範圍爲ΝΑ = 0· 06〜 0.22rad之範圍。 此外，將發散入射方式與使用分割成mXn之複合透鏡 之眾所皆知之實例進行比較，因爲可消除各透鏡之境界部 -20 - 200535409 (17) 份所產生之反射損失之影響，聚光透鏡1 3之入射側對光纖 1 0 1之射出側之傳送效率可提高大約〗〇%。 此外，因爲發散入射方式可減少光學要素之個數，故 可降低雷射光入射光學裝置11整體之成本。 因此，採用含有石英之材質、對於芯徑之纖殼厚度爲 0.0 3 5〜0.1倍、數値孔徑NA爲0.06〜0.22之階變折射型光 纖101，使尖鋒功率超過10MW之巨脈波振盪方式之固體雷 φ 射振盪器1 1 1之雷射光L以呈發散性方式入射至該光纖1 0 1 之入射端面1 02，可在光纖1 〇 1不會受損之情形下傳送雷射 光L，且傳送效率不會降低，此外，無需複雜之調整且更 價格更爲低廉。 其次，參照第1 〇圖，針對雷射光入射光學裝置11之其 他實施形態進行說明。 此外，與利用第1圖至第9圖所示之實施形態進行說明 之構成相同或類似之構成’附與相同符號並省略詳細說明 •。 雷射光入射光學裝置Π具有：用以對固體雷射振盪器 1 1 1之雷射光L附與特定聚光性之聚光透鏡1 3 ;用以使聚光 透鏡1 3及光纖1 〇 1之入射端面1 〇2間之距離維持於一定距離 之光纖位置調整機構1 5 ;配設於固體雷射振盪器1 1 1及聚 光透鏡1 3之間，用以從固體雷射振盪器Π 1朝聚光透鏡1 3 之雷射光L分離出光纖之入射端面1〇2反射之反射雷射 光（戻雷射光）R之半透明鏡之光束分岐器（抽樣鏡）31 ;用以 受取該光束分岐器3 1分離之反射雷射光R並對應該強度輸 -21 - 200535409 (18) 出電性訊號，例如，具有光電變換元件之觀測手段之CCD 攝影機32。此外，CCD攝影機32及光束分岐器31之間，配 設著使利用光束分岐器31分離之反射雷射光R在CCD攝影 機3 2之圖上未標示之受光面上成像之成像透鏡3 3，此外’ 必要時，可在成像透鏡33及CCD攝影機32之間配設用以調 整入射至CCD攝影機32之反射雷射光R強度之衰減濾光器 等光量調整裝置34。 • CCD攝影機32會依據入射至光纖101之入射端面102之 雷射光L之入射位置之資訊形成圖像。因此，依據CCD攝 影機3 2所得到之入射端面1 〇 2之圖像，例如，以例如未詳 述之移動機構移動光纖位置調整機構1 5之光纖保持部1 7之 位置，可將光纖1 〇 1之入射端面1 0 2之位置及成像透鏡1 3間 之距離設定成利用第2圖〜第4圖說明之期望位置。 此外，若聚光透鏡1 3之焦點距離爲f!、成像透鏡3 3之 焦點距離爲f 2、光纖1 0 1之入射端面1 〇 2至成像透鏡1 3之距 # 離爲a，且應設置CCD攝影機32之位置（至光纖101之入射端 面1 02之距離）爲b、聚光透鏡1 3及成像透鏡3 3間之距離爲d 、倍率爲m，則可分別以下述諸式表示。 b= (1+m) Xf2—m2Xa ..-(11) m= f 2/ f i …（1 2) d = f 2+ f ! …（1 3) 因此，利用（1 2 )式決定聚光透鏡1 3之焦點距離f!及欲 觀測之像倍率m之成像透鏡3 3之焦點距離f2 ’其次’利用 (13)式及（11)式決定2個透鏡間之間隔（距離d)及C CD攝影機 3 2之位置等，故可對光纖1 〇 1之入射端面1 0 2進行觀測。 -22- 200535409 (19) 例如，若聚光透鏡1 3之焦點距離爲f! = 3 1 m m ’以使光 束分岐器（抽樣鏡）3 1相對於固定雷射振盪器1 1 1朝聚光透鏡 13之雷射光L之主光線呈45度之角度進行配置’並使CCD 攝影機3 2位於成像透鏡3 3之後方特定位置’來自光纖1 0 1 之入射端面102之反射雷射光R在CCD攝影機32形成圖像， 可利用圖上未標示之TV監視器進行觀測，同時實施入射調 整。 • 此外，使像倍率πι成爲大約3倍時，若利用（12)式使成 像透鏡33之焦點距離成爲例如f2 = l 〇〇mm ’則利用（13)式求 取之聚光透鏡1 3及成像透鏡3 3間之距離d大約爲1 3 1 m m。 此外，因爲聚光透鏡1 3及光纖1 〇 1之入射端面1 02間之距離 a大約爲33mm，故成像透鏡33及CCD攝影機32間之距離大 約爲7 9 m m。此時，依據（1 1)式’像倍率hi大約爲3 · 2倍。 利用光纖位置調整機構1 5實施之光纖.1 0 1之入射端面 102及聚光透鏡13間之距離a調整’除了雷射光入射光學裝 # 置1 1之組合調整以外，並非必要，故利用於光束分岐器3 1 、C CD攝影機32、以及成像透鏡33等之入射狀態之監視器 時之構成上，可以爲可從固體雷射振盪器1 Π及聚光透鏡 1 3間之光路拆除之構成。 其次，參照第1 1圖，針對雷射光入射光學裝置Π之其 他實施形態進行說明。 第11圖係將雷射光入射光學裝置U應用於雷射誘導螢 光分析裝置（使用 Laser Induced Breakdown Spectroscopy之 高速分析裝置）之實例。雷射誘導螢光分析裝置可分析之 -23- 200535409 (20) 試料（分析對象物）種類受到少許限制，然而，因爲具有可 簡化準備試料之前處理階段、速度快、以及分析對象物爲 固體時可直接使用等各種優點，故可應用之範圍十分廣泛 〇 如第Π圖所示，雷射誘導螢光分析裝置301具有巨脈 波（GP)振盪方式之固體雷射振盪器1 Π、雷射光入射光學 裝置（雷射光傳送系統··導光光學系）Π、照射光學系3 3 1、 • 螢光檢測光學系341、單色器（光檢測器或分光器）351、攝 像機構3 6 1、時序調整機構3 7 1、以及資料處理裝置3 8 1等 〇 固體雷射振盪器1Π係例如Nd : YAG雷射等。此外， 固體雷射振盪器1 1 1輸出之雷射光L之大小，例如，脈波期 間爲5nseC前後、尖鋒功率爲14〜20MW、傳送能量爲70〜 lOOmJ(尖鋒功率密度爲80GW/cm2)程度。此外，固體雷射 振盪器Π 1通常含有振盪控制裝置、電源裝置、以及冷卻 #裝置等，然而，省略其詳細說明。 雷射光入射光學裝置11係與利用第1圖或第10圖進行 說明者相同，含有使固體雷射振盪器ill之雷射光L呈發散 性入射至光纖1 0 1之入射端面1 02之聚光透鏡1 3等。此外， 聚光透鏡1 3及光纖1 0 1之入射端面1 0 2間之距離設定與上述 實施形態相同。 例如，光纖101之芯徑爲1000μηι、纖殼層厚度爲50μηι 時，爲了使利用聚光透鏡1 3進行聚光並利用通過聚光點而 呈發散性之擴散角爲〇 . 0 6〜〇 . 2 2 r a d之剖面束徑改變之雷射 -24- 200535409 (21) 光L能有效入射，應爲〇 . 〇 6〜〇 . 2 2之數値孔徑N A。 照射光學系3 3 1具有聚光透鏡3 3 3，用以使從雷射光入 射光學裝置11之光纖101之射出端面106射出之暫時呈現發 散性之脈波雷射光L，聚光於試料S或用以保持試料S之試 料保持部3 99之特定範圍。此外，聚光透鏡3 3 3之特性可配 合試料S之大小及形狀進行任意設定。 螢光檢測光學系（檢測光導光光學系）3 4 1具有用以捕獲 • 來自位於試料保持部3 99上之試料S之螢光之聚光透鏡343 '及用以使利用聚光透鏡3 43捕獲之螢光入射至後段之分 光器（單色器）之光纖3 4 5。 單色器3 5 1係例如配合含有光柵（繞射光柵）及波長濾波 器等之眾所皆知之分光計或試料S之特性而任意組合之檢 測機構。 攝像機構3 6 1係受取利用單色器3 5 1析出之特定波長之 光（螢光），並對其光強度輸出電性訊號，例如，眾所皆知 ^ 之CCD攝影機、光電倍增器、或FFT分析器等，可配合試 料S之特性而任意選擇。 時序調整機構3 7 1係例如脈波產生器或雷射誘導螢光 分析裝置3 0 1之主控制裝置，用以控制供應給固體雷射振 盪器1 1 1之圖上未標示之電源裝置之驅動脈波之輸出時序 、及例如閘極控制型I-C CD之C CD攝影機之動作時序等， 而以特定時序攝取試料S產生之螢光。 資料處理裝置3 8 1係用以暫時儲存攝像機構3 6 1輸出之 圖像或光譜等，依據預先儲存之「元素識別程式」、「元 -25- 200535409 (22) 素定量程式」、或對攝像機構3 6 1提供之圖像資料等實施 特定處理之算則等，進行試料S之特性解析、或其前階段 之資料處理。 第1 1圖所示之雷射誘導螢光分析裝置3 0 1時，係利用 主控制裝置3 9 1 (第1 1圖之實例係與時序調整裝置3 7 1爲一 體化）依特定時序產生驅動脈波，並依據該驅動脈波由固 體雷射振盪器1 Π以特定脈波期間輸出尖鋒功率爲1 4〜 φ 2〇MW之GP方式之脈波雷射光L。 固體雷射振盪器1 U輸出之脈波雷射光L經由聚光透鏡 1 3變換成呈現發散性，有效地入射至光纖1 〇丨而被傳送至 光纖101之射出端面106。 利用照射光學系3 3 1之聚光透鏡3 3 3使光纖1 〇 1射出之 雷射光L照射於試料S。此外，如前面說明所示，雷射光L 之尖鋒功率爲14〜2 0MW，利用聚光透鏡3 3 3聚光成例如數 百μπι之直徑，而照射於試料S時之尖鋒功率密度爲 ® 80GW/cm2。因此，試料S被電漿化，該電漿能量使存在於 試料中之各元素分別放射出固有之螢光（含有螢光之光譜） 〇 利用螢光檢測光學系341之聚光透鏡343捕獲該發光（ 含有螢光之光譜），並經由光纖345入射至單色器351。 其後’利用單色器3 5 1除去試料S本體之光譜成分等， 析出試料S所含有之元素之固有光譜。 利用攝像機構3 6 1實施以單色器3 5 1析出之光譜之光電 變'換’並提供給資料處理部3 8 1，資料處理部3 8 1則特定試 -26- 200535409 (23) 料s所含有之元素。例如，攝像機構361爲例如FFT分析器 時，可利用作業者之目視來特定試料s所含有之元素。 此外，因爲至得到試料S所含有之元素之固有螢光光 譜爲止，會比電漿發光（亦即，雷射光L之照射）延遲數psec 〜數百μ s e c，故利用時序調整機構3 7 1 (主控制裝置3 9 1 )來 控制攝像機構3 6 1之動作。例如，攝像機構3 6 ]爲附閘極之 C C D攝影機時，除了在計測時間加上特定延遲以外，尙在 ^ 特定時序導通閘極，而可只計測必要之螢光光譜。 此外，上述雷射誘導螢光分析裝置301幾乎不需要如 I C P發光分析之試料之前處理，故可迅速測定。此外，因 爲雷射誘導螢光分析裝置1 1對試料照射雷射光L時，空間（ 場所及大小）限制較少，利用單元化可在測定對象物存在 之任意場所實施測定對象物之分析。 利用如以上所示之雷射誘導螢光分析裝置1 1，光學構 件數較少且較便宜卻更有效率，無需使用光束放大用準直 ^ 儀及光束分割用陣列透鏡，只要使用1片或2片聚光透鏡（ 凸透鏡）即可入射至光纖。 此外，可以較便宜之成本提供較小型之利用尖鋒功率 超過10MW之巨脈波振盪方式之雷射光L之例如雷射誘導螢 光分析、雷射剝蝕、以及雷射擊等之處理所使用雷射光入 射光學裝置1 1。 此外，並未受限於前述各實施形態，在實施上，只要 不背離其要旨範圍，可進行各種變形或變更。此外，亦可 將各實施形態進行適當組合，此時，可得到組合之效果。 -27- 200535409 (24) 依據本發明，係利用採用含有石英之材質、對於芯徑 之纖殻厚度爲0.03 5〜01倍、數値孔徑NA爲0.06〜0.22之 階變折射型光纖、及使尖鋒功率超過10MW之巨脈波振盪 方式之固體雷射振盪器之雷射光對該光纖之入射端面實施 呈發散性之入射，可在光纖不會受損的情形下傳送雷射光 ’不會降低傳送效率亦無需複雜之調整，且只要較便宜之 成本。 【圖式簡單說明】 第1圖係本發明之雷射光入射光學裝置之實施形態之 實例槪略圖。 第2圖係說明發散入射方式之聚光光學系之傳送模式 之槪略圖。 第3圖係對光纖之入射角及聚光透鏡之焦點距離之關 係圖。 • 第4圖係對光纖之入射角及聚光透鏡之入射發散角之 關係圖。 第5圖係對光纖之入射方式及傳送能量之關係圖。 第6A圖係光纖之軸線方向之剖面圖。 第6B圖係與第6A圖所示之光纖之軸線方向垂直相交之 方向之剖面圖。 第7圖係纖殻厚度及傳送能量之關係圖。 第8圖係芯徑及傳送能量之關係圖。 第9圖係對光纖之入射角及傳送能量之關係圖。 - 28- 200535409 (25) 第1 〇圖係本發明之雷射光入射光學裝置之其他實施形 態之槪略圖 第1 1圖係組合著本發明之雷射光入射光學裝置之雷射 誘導螢光分析裝置之實例槪略圖。 【主要元件符號說明】 11 雷射光入射光學裝置 13 聚光透鏡 15 光纖位置調整機構 16 聚光透鏡保持部 17 光纖保持部 18 調整部 3 1 光束分岐器 32 CCD攝影機 3 3 成像透鏡 34 光量調整裝置 101光纖 102入射端面 103 芯 104纖殼 1 〇 5被覆層 106射出端面 1 1 1固體雷射振盪器 3 3 1照射光學系 -29- 200535409 (26) 3 3 3聚光透鏡 341螢光檢測光學系 3 4 3聚光透鏡 3 4 5光纖 351單色器 361攝像機構 3 7 1時序調整機構 3 8 1資料處理裝置 391主控制裝置 3 99試料保持部The refractive index of 103 is n! And the refractive index of the fiber shell 104 is n2. The numerical aperture NA φ can be specified by the following formula. ΝΑ =, [(ηι) 2- (η2) 2] In addition, in order to increase the number of optical fibers 1 0 1 値 aperture NA, the method of reducing the refractive index of the fiber 104 layer is widely used. The amount of fluorine and boron in the 04 layer will make it brittle and easily broken. In addition, if the thickness of the fiber shell 104 obtained by using FIG. 7 is considered, the upper limit of the number of apertures NA according to the above-mentioned irradiation optical system should be approximately 0.221 * ad which is lower. Therefore, the upper limit of the number NA of the optical fiber 101 is 0.22. In addition, # Because the upper limit 値 will be changed according to the actual structure and physical properties of the optical fiber 〇1, the upper limit of the number 値 of the optical fiber 〇1 that can be set when the divergent incidence method is not necessarily 0.22, and The number specified in accordance with the structure characteristics and physical properties of the optical fiber 101. In addition, the core diameter is not affected by the condenser lens described with reference to Figs. 3 and 4, the focal position of 13 and the incident angle θ2 of the laser light L incident on the optical fiber 100, and the optical fiber described with reference to Fig. 8. The experimental results of the restrictions on the core diameter of 1 0 1 and the aperture (cross-section beam diameter) of the laser light L incident on the optical fiber 1 1 and the results of the confirmation of the energy transmission capability using Figure 9 confirm the lower limit. -18- 200535409 (15) The incident angle θ2 of the light L may be equal, so the numerical aperture NA == 0.06 ~ 0.22rad 〇 As can be seen from the above description, it is possible to transmit 2 0 MW (diffusive incident mode) Front power density is 100 GW / cm2) The optical fiber 1 of the laser light L with a giant pulse wave oscillation method of 010 should be between the core 103 with a diameter of 500 to 1500 μηι, and the thickness of the fiber shell 104 between 35 and 100 μm. The number of apertures NA of the optical fiber 101 is in the range of 0.06 to 0.22. In addition, the incident angle θ2 of the laser light L incident to the optical fiber 101 should be a relatively large angle within the range allowed by the configuration of the laser light incident optical device 11. From the above, in order to stably transmit the pulsed laser light L with a peak power of 10 MW or above, or the short pulsed laser light L with a peak power of 10 MW or less, for example, when the number of the optical fiber 101 is equal to 0.2, The incident angle θ2 of the #laser light L incident on the optical fiber 101 should be up to 0.2rad (the upper limit of the number of the optical fiber 101 (the upper limit of the aperture NA)). Next, a specific example of the laser light incident optical device 11 will be described. In addition, the numbers shown below are the data of the laser light L with a peak power of 22 MW as described before FIG. 9. For example, the following conditions are used to transmit and change the optical fiber 1 〇1 of the step-change refractive type quartz material. Nd of the giant pulse wave oscillation method: The solid laser oscillator U1 of the YAG laser oscillator has a pulse period of 5nsec and a pulse energy of 0mJ (the peak power is 22MW = n0mJ / 5nsec) -19- 200535409 (16) Result of laser light L with a diameter of 6mm. Incident angle (incident divergence angle) of condenser lens 13 ei = 1.8mrad (half angle) Laser aperture (section beam diameter) r (radius) = 3 mm (diameter 6 mm) Condenser lens 13 and solid laser oscillation The distance D of the condenser 1 1 1 is 6,000 mm. The focal distance of the condenser lens 1 3 is f = 3 1 mm. The core diameter of the optical fiber 1 0 1 is οοο μη. The thickness of the fiber case 1 〇4 is 50 μm. The number of apertures NA = 0.2rad. Incident angle e2 of the laser light L to the optical fiber 101 = 0.13rad (half angle) The distance Lf between the light-condensing point A of the condenser lens 13 and the incident end surface 102 of the optical fiber L2 = 2mm to the laser light L of the optical fiber 101 Incident aperture (cross-section beam diameter): 700 μπα (diameter) In addition, when the above-mentioned number is used to determine the incident angle θ2 to the optical fiber • 101 using the formula (4), that is, the incidence to the condenser lens 13 is used. Angle (incident divergence angle) θ! = 1.8 mr ad, the distance D between the condenser lens 13 and the solid-state laser oscillator 111! = 60 Omm, the laser entrance aperture (section beam diameter) r (radius) = 3 mm, and When the focal distance f of the condensing lens 13 is 3 mm, and when the angle of incidence θ2 to the optical fiber 101 described above is obtained by the formula (4), the angle of incidence θ2 = 0.1 3 rad. It is considered that the range of the numerical aperture of the optical fiber 101 that can be used in the present invention is in the range of NA = 0.06 to 0.22 rad. In addition, the divergent incidence method is compared with a well-known example using a compound lens divided into mXn, because the influence of the reflection loss caused by the boundary part of each lens can be eliminated. The transmission efficiency of the incident side of the lens 13 to the exit side of the optical fiber 101 can be improved by about 0%. In addition, since the number of optical elements can be reduced by the divergent incidence method, the cost of the laser light incident on the entire optical device 11 can be reduced. Therefore, using a step-variable refractive fiber 101 containing quartz with a thickness of 0.03 5 to 0.1 times the core diameter and a NA of 0.06 to 0.22, the peak power exceeds 10 MW. The solid-state laser φ laser oscillator 1 1 1 emits the laser light L incident on the incident end face 102 of the optical fiber 1 0 1 in a divergent manner, and can transmit the laser light L without damaging the optical fiber 101. And, the transmission efficiency will not be reduced. In addition, no complicated adjustment is needed and the price is lower. Next, another embodiment of the laser light incident optical device 11 will be described with reference to FIG. 10. In addition, the same or similar components as those explained using the embodiments shown in Figs. 1 to 9 are denoted by the same reference numerals and detailed explanations are omitted. The laser light incident optical device Π includes: a condenser lens 1 3 for attaching the laser light L of the solid-state laser oscillator 1 1 1 to a specific condensing property; and a condenser lens 13 and an optical fiber 1 〇1. Optical fiber position adjustment mechanism 15 maintaining a distance between the incident end faces 10 and 20; disposed between the solid-state laser oscillator 1 1 1 and the condenser lens 13, and used to separate the solid-state laser oscillator Π 1 A beam splitter (sampling mirror) 31 of a translucent mirror reflecting the reflected laser light (戻 laser light) R reflected by the incident end surface 102 of the optical fiber toward the laser light L of the condenser lens 13; used to receive the beam divergence The reflected laser light R, which is separated by the device 31, outputs -21-200535409 (18) an electrical signal according to the intensity, for example, a CCD camera 32 having an observation means of a photoelectric conversion element. In addition, between the CCD camera 32 and the beam splitter 31, there is an imaging lens 3 3 for imaging the reflected laser light R separated by the beam splitter 31 on a light receiving surface not shown on the figure of the CCD camera 32. 'If necessary, a light amount adjustment device 34 such as an attenuation filter for adjusting the intensity of the reflected laser light R incident on the CCD camera 32 may be provided between the imaging lens 33 and the CCD camera 32. • The CCD camera 32 forms an image based on the information of the incident position of the laser light L incident on the incident end face 102 of the optical fiber 101. Therefore, based on the image of the incident end surface 102 obtained by the CCD camera 32, for example, the position of the optical fiber holding portion 17 of the optical fiber position adjusting mechanism 15 can be moved by a movement mechanism (not described in detail), and the optical fiber 1 can be removed. The position of the incident end surface 1 2 of 1 and the distance between the imaging lens 13 are set to the desired positions described with reference to FIGS. 2 to 4. In addition, if the focal distance of the condenser lens 13 is f !, the focal distance of the imaging lens 33 is f 2, and the distance # from the incident end face 1 of the optical fiber 10 to the imaging lens 13 is a, and should be a If the position of the CCD camera 32 (the distance from the incident end surface 102 of the optical fiber 101) is b, the distance between the condenser lens 13 and the imaging lens 33 is d, and the magnification is m, it can be expressed by the following formulas. b = (1 + m) Xf2—m2Xa ..- (11) m = f 2 / fi… (1 2) d = f 2+ f!… (1 3) Therefore, the light concentration is determined using the formula (1 2) The focal distance f of the lens 1 3 and the focal distance f2 of the imaging lens 3 3 to be observed 'next' use the formulas (13) and (11) to determine the interval (distance d) and C between the two lenses. The position of the CD camera 32, etc., allows observation of the incident end face 102 of the optical fiber 101. -22- 200535409 (19) For example, if the focal distance of the condenser lens 1 3 is f! = 3 1 mm ', the beam splitter (sampling mirror) 3 1 is focused toward the fixed laser oscillator 1 1 1 The main light of the laser light L of the lens 13 is arranged at an angle of 45 degrees, and the CCD camera 3 2 is located at a specific position behind the imaging lens 33. The reflected laser light R from the incident end surface 102 of the optical fiber 1 0 1 is on the CCD camera. 32 forms an image, which can be observed using a TV monitor not shown in the figure, and incident adjustment is performed at the same time. • In addition, when the image magnification πm is approximately 3 times, if the focal distance of the imaging lens 33 is set to, for example, f2 = l00mm 'using the formula (12), the condenser lenses 13 and 13 obtained using the formula (13) are obtained. The distance d between the imaging lenses 33 is approximately 13 1 mm. In addition, since the distance a between the condenser lens 13 and the incident end surface 102 of the optical fiber 101 is approximately 33 mm, the distance between the imaging lens 33 and the CCD camera 32 is approximately 7.9 mm. At this time, the image magnification hi according to the formula (1 1) 'is approximately 3.2 times. The optical fiber implemented by the optical fiber position adjustment mechanism 15 is used to adjust the distance a between the incident end surface 102 of the 101 and the condenser lens 13 except for the combination adjustment of the laser light incident optical device # 1 1, so it is used for The beam splitter 3 1, the CC camera 32, and the imaging lens 33 can be detached from the optical path between the solid-state laser oscillator 1 and the condenser lens 13 when the monitor is in the state of incidence. . Next, referring to Fig. 11, another embodiment of the laser light incident optical device Π will be described. Fig. 11 shows an example in which the laser light incident optical device U is applied to a laser-induced fluorescence analysis device (a high-speed analysis device using Laser Induced Breakdown Spectroscopy). The laser-induced fluorescence analyzer can analyze -23- 200535409 (20) The type of sample (analytical object) is slightly limited, however, because it can simplify the processing stage before sample preparation, fast speed, and when the analysis object is solid Various advantages such as direct use can be used, so the application range is very wide. As shown in Figure Π, the laser-induced fluorescence analysis device 301 has a solid-state laser oscillator 1 with a giant pulse wave (GP) oscillation method. Π, laser light Incident optical device (laser light transmission system · light-guiding optical system) Π, irradiation optical system 3 3 1, • Fluorescence detection optical system 341, monochromator (light detector or beam splitter) 351, imaging mechanism 3 6 1 , Timing adjustment mechanism 3 71, and data processing device 3 81, etc. 〇 The solid-state laser oscillator 1 Π is, for example, Nd: YAG laser. In addition, the size of the laser light L output by the solid-state laser oscillator 1 1 1 is, for example, 5nseC before and after the pulse wave period, a peak power of 14 to 20 MW, and a transmission energy of 70 to 100 mJ (a peak power density of 80 GW / cm2). )degree. In addition, the solid-state laser oscillator Π 1 generally includes an oscillation control device, a power supply device, a cooling device, and the like. However, detailed descriptions thereof are omitted. The laser light incident optical device 11 is the same as that described with reference to FIG. 1 or FIG. 10. The laser light incident optical device 11 includes the light condensing that makes the laser light L of the solid-state laser oscillator ill enter the optical fiber 1 0 1 and the incident end surface 102 of the optical fiber 1 divergently. Lenses 1 3 and so on. In addition, the distance between the condenser lens 13 and the incident end surface 102 of the optical fiber 101 is set in the same manner as in the above embodiment. For example, when the core diameter of the optical fiber 101 is 1000 μηι, and the thickness of the fiber shell layer is 50 μηι, in order to condense the light using the condenser lens 13 and utilize a divergent diffusion angle passing through the condensing point to 0.0 6 ~ 〇. 2-24 rad laser beam with a changed beam diameter-24-200535409 (21) Light L can be effectively incident and should be a number 値 aperture NA of 0.06 to 0.2. The irradiation optical system 3 3 1 has a condenser lens 3 3 3 for condensing the pulsed laser light L, which is temporarily divergent, emitted from the exit end face 106 of the optical fiber 101 of the optical device 11 and focused on the sample S or A specific range of the sample holding portion 3 99 for holding the sample S. In addition, the characteristics of the condenser lens 3 3 3 can be arbitrarily set according to the size and shape of the sample S. The fluorescence detection optical system (detection light guide optical system) 3 4 1 has a condenser lens 343 ′ for capturing and emitting fluorescence from the sample S on the sample holding section 3 99 and a condenser lens 3 43 The captured fluorescent light enters the optical fiber 3 4 5 of the beam splitter (monochromator) at the rear stage. The monochromator 3 5 1 is a detection mechanism arbitrarily combined with characteristics of a spectrometer or a sample S including a grating (diffraction grating), a wavelength filter, and the like. The imaging mechanism 3 6 1 receives light (fluorescence) of a specific wavelength that is emitted by the monochromator 3 51 and outputs an electrical signal to its light intensity. For example, CCD cameras, photomultipliers, Or FFT analyzer, etc., can be arbitrarily selected according to the characteristics of the sample S. The timing adjustment mechanism 3 7 1 is a main control device such as a pulse wave generator or a laser-induced fluorescence analysis device 3 0 1 for controlling a power supply device not shown on the diagram of the solid-state laser oscillator 1 1 1. The output timing of the driving pulse wave, and the operation timing of the gate-controlled IC CD C CD camera, etc., take in the fluorescence generated by the sample S at a specific timing. The data processing device 3 8 1 is used to temporarily store the images or spectra output by the imaging mechanism 3 6 1. According to the “element recognition program” stored in advance, “Yuan-25- 200535409 (22) prime quantitative program”, or The image data and the like provided by the imaging mechanism 3 61 are subjected to specific processing algorithms, etc., to perform the characteristic analysis of the sample S or the data processing at the previous stage. The laser-induced fluorescence analysis device 3 01 shown in FIG. 11 is generated by using a main control device 3 9 1 (the example in FIG. 11 is integrated with the timing adjustment device 3 71) according to a specific timing. The driving pulse wave, and according to the driving pulse wave, the solid-state laser oscillator 1 Π outputs the GP-type pulse wave laser light L with a peak power of 14 to φ 20 MW during a specific pulse wave period. The pulsed laser light L output from the solid-state laser oscillator 1 U is converted into a divergence by the condenser lens 13, and is effectively incident on the optical fiber 10 and transmitted to the exit end 106 of the optical fiber 101. A sample lens S is irradiated with laser light L emitted from the optical fiber 101 using a condenser lens 3 3 3 that irradiates the optical system 3 3 1. In addition, as shown in the foregoing description, the peak power of the laser light L is 14 to 20 MW, and the condenser lens 3 3 3 is used to condense a diameter of, for example, several hundred μm, and the peak power density when the sample S is irradiated is ® 80GW / cm2. Therefore, the sample S is plasmatized, and the energy of the plasma causes each element present in the sample to radiate inherent fluorescence (spectrum containing fluorescence). 〇 The condenser lens 343 of the fluorescence detection optical system 341 is used to capture this. It emits light (spectrum containing fluorescence) and enters the monochromator 351 through the optical fiber 345. After that, the monochromator 3 5 1 is used to remove the spectral components and the like of the sample S body, and the intrinsic spectrum of the elements contained in the sample S is precipitated. Use the imaging mechanism 3 6 1 to implement the photoelectric conversion of the spectrum separated by the monochromator 3 5 1 and provide it to the data processing unit 3 8 1 and the data processing unit 3 8 1. Specific tests-26- 200535409 (23) Elements contained in s. For example, when the imaging mechanism 361 is, for example, an FFT analyzer, the elements contained in the sample s can be specified by using the eyes of the operator. In addition, because the inherent fluorescence spectrum of the element contained in the sample S is obtained, it will be delayed by a number psec to several hundred μ sec from the plasma light emission (that is, the irradiation of the laser light L), so the timing adjustment mechanism is used 3 7 1 (Main control device 3 9 1) to control the operation of the imaging mechanism 3 6 1. For example, when the imaging mechanism 36 is a CC camera with a gate, in addition to adding a specific delay to the measurement time, the gate can be turned on at a specific timing, and only the necessary fluorescence spectrum can be measured. In addition, the above-mentioned laser-induced fluorescence analysis device 301 requires almost no prior processing of samples such as I C P luminescence analysis, and therefore can be measured quickly. In addition, when the laser-induced fluorescence analysis device 11 irradiates the sample with the laser light L, there are fewer restrictions on space (place and size), and the unit can be used to analyze the measurement object at any place where the measurement object exists. With the laser-induced fluorescence analysis device 11 shown above, the number of optical components is smaller and cheaper but more efficient. There is no need to use a collimator for beam magnification and an array lens for beam splitting. Just use one or Two condenser lenses (convex lenses) can be incident on the optical fiber. In addition, it is possible to provide a smaller type of laser light L using a giant pulse wave oscillation mode with a peak power exceeding 10MW, such as laser-induced fluorescence analysis, laser ablation, and laser shooting. Incident optics 1 1. In addition, the present invention is not limited to the foregoing embodiments, and various modifications and changes can be made without departing from the scope of the gist. In addition, the respective embodiments can be appropriately combined, and in this case, the combined effect can be obtained. -27- 200535409 (24) According to the present invention, a step-varying refractive optical fiber using a material containing quartz, having a thickness of 0.03 5 to 01 times the core diameter and a NA of 0.06 to 0.22 is used. The laser light of a solid laser oscillator with a giant pulse wave oscillation mode with a peak power of more than 10MW is subjected to divergent incidence on the incident end face of the optical fiber, and the laser light can be transmitted without the optical fiber being damaged. The transmission efficiency also does not require complicated adjustments, and only has to be cheaper. [Brief description of the drawings] Fig. 1 is a schematic diagram of an example of an embodiment of a laser light incident optical device according to the present invention. Fig. 2 is a schematic diagram illustrating a transmission mode of a condensing optical system of a divergent incidence method. Figure 3 is a diagram showing the relationship between the incident angle of the optical fiber and the focal distance of the condenser lens. • Figure 4 shows the relationship between the incident angle of the optical fiber and the incident divergence angle of the condenser lens. Figure 5 is a diagram showing the relationship between the incidence of the fiber and the transmitted energy. Figure 6A is a cross-sectional view in the axial direction of the optical fiber. Fig. 6B is a sectional view in a direction perpendicular to the axis direction of the optical fiber shown in Fig. 6A. Fig. 7 is a graph showing the relationship between the fiber shell thickness and the transmitted energy. Fig. 8 is a relationship diagram of core diameter and transmission energy. Fig. 9 is a diagram showing the relationship between the incident angle to the optical fiber and the transmitted energy. -28- 200535409 (25) Fig. 10 is a schematic diagram of another embodiment of the laser light incident optical device of the present invention. Fig. 11 is a laser induced fluorescence analysis device combined with the laser light incident optical device of the present invention. The example is sketched. [Description of main component symbols] 11 Laser light incident optical device 13 Condensing lens 15 Fiber position adjustment mechanism 16 Condensing lens holding portion 17 Fiber holding portion 18 Adjusting portion 3 1 Beam splitter 32 CCD camera 3 3 Imaging lens 34 Light quantity adjusting device 101 optical fiber 102 incidence end surface 103 core 104 fiber shell 1 〇5 coating layer 106 emission end surface 1 1 1 solid-state laser oscillator 3 3 1 irradiation optical system-29- 200535409 (26) 3 3 3 condenser lens 341 fluorescence detection optics System 3 4 3 Condensing lens 3 4 5 Optical fiber 351 Monochrome 361 Camera mechanism 3 7 1 Timing adjustment mechanism 3 8 1 Data processing device 391 Main control device 3 99 Sample holding unit
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