201110488 六、發明說明： 【發明所屬之技術領域】 本發明是關於被動式Q切換雷射’特別是關於以固定振幅 為激發光源的被動式光纖脈衝雷射系統。 【先前技術】 Q切換雷射為一種高功率脈衝雷射，分為主動式與被動 • 式。主動式㈣換雷射需要提供外部電子驅動信號於光纖，以 改變光的特性。該外部電子驅動信號需要極短的脈衝去驅動q 切換雷射的開關，而使該開關達到快速開啟與關閉的功能，缺 而產生該外部電子訊號龄備價格昂責。被動式Q切換雷射 則是以摻雜稀土(rare earth)金屬的晶體作為雷射脈衝的開關切 換器，然而這些摻雜稀土金屬的光纖卻難以製作或取得。 美國專利第5652756號公開專利及美國第20060007965號 公開專利的技術特徵皆非全光纖型的結構，光必須離開光纖: • 處理後在輕合回光纖，美國公開號第7130319號的技術特徵雖 為全光纖型，但是必須使用主動式Q切換元件。 中華民國第96H4909號專利申請，全光纖型被動式㈣ 換雷^，該專_為全絲型且馳動式㈣換雷射。 請參閱第一圖，其為習用全光纖型被動式Q切換雷射系統 的示意圖。該全光纖型被動式Q切換雷射系統10包含一激發 光源11、一激發光束12、一第一光柵13、一增益光纖14、I 飽和=收光纖15、—第二光柵16、以及一雷射脈衝17。 當該激發光束12激發該增益光纖14時，該增益光纖u 會產生—自體11射光束（未顯示）和-雷射增益光束（未顯 201110488 示）該第-光栅13全反射該自體輻射光束和該雷射增益光束 至該第二光柵16，而於該第一光柵13與該第二光栅16之間 共振。該共振雷射光（未顯示）經過該第二光柵16後，一部分 輸出部分反射繼續共振。雷射脈衝的形成是從自體輕射光 束的放大開始。該自體輻射光束經過該增益光纖14會被放 大，而經過該飽和吸收光纖15會因被吸收而變小，使得自體 輻射光束一開始被抑制而無法放大成雷射。但當該飽和吸收光 纖15到達吸收餘和狀態後即不再吸收，此時自體輻射會在來 • 回共振中被該增益光纖14快速放大，而形成該雷射脈衝17。 該全光纖型被動式Q-切換雷射系統1〇的缺點是：提供的激發 光源11必須是振幅可調變式的才能產生連續的雷射脈衝。 凊參閱第二圖，其為習用全光纖式飽和吸收Q切換雷射系 統的示意圖。該全光纖式飽和吸收Q切換雷射系統2〇具有一 環型共振腔27之結構，該全光纖式飽和吸收q切換雷射系統 20包含一增益光纖21、一飽和吸收光纖22、一光循環器23、 一光纖光柵24、一雷射脈衝28、一增益區域Rg、以及一光強 | 度強化區域Re。 該增益光纖21設於全光纖式飽和吸收q切換雷射系統2〇 之該增益區域RG内’該增益光纖21受一激發光源25激發而產 生雷射光束輸出至光循環器23。該光循環器23接收該增益光 纖21所輸出之雷射光’該光循環器23控制該環型共振腔27 的共振方向，使光的方向只能從該光循環器23的端點A前進 至端點B、以及從端點B前進至端點該光循環器23同時可 排除該激發光源25，以避免該飽和吸收光纖22吸收該激發光 源25。 該光纖光柵24設於該光循環器23之一輸出側，該光纖光^ 201110488201110488 VI. Description of the Invention: TECHNICAL FIELD OF THE INVENTION The present invention relates to passive Q-switched lasers, particularly to passive fiber-optic pulsed laser systems that use a fixed amplitude as an excitation source. [Prior Art] Q-switched laser is a high-power pulsed laser, which is divided into active and passive. Active (four) laser replacement requires an external electronic drive signal to be applied to the fiber to change the characteristics of the light. The external electronic drive signal requires a very short pulse to drive the switch to switch the laser, so that the switch can be quickly turned on and off, and the external electronic signal is inevitably blamed. The passive Q-switched laser is a switch that uses a rare earth metal crystal as a laser pulse. However, these rare earth doped fibers are difficult to fabricate or obtain. The technical features of the U.S. Patent No. 5,652,756 and U.S. Patent No. 20060007965 are not all-fiber type structures, and the light must leave the optical fiber: • After the processing, the optical fiber is lightly combined, and the technical feature of U.S. Patent No. 7,130,319 is All-fiber type, but active Q switching elements must be used. Patent application No. 96H4909 of the Republic of China, all-fiber type passive (four) for lightning, this special _ is full-wire type and turbulent type (four) for laser. Please refer to the first figure, which is a schematic diagram of a conventional all-fiber passive Q-switched laser system. The all-fiber passive Q-switched laser system 10 includes an excitation light source 11, an excitation beam 12, a first grating 13, a gain fiber 14, an I saturation = a receiving fiber 15, a second grating 16, and a laser. Pulse 17. When the excitation beam 12 excites the gain fiber 14, the gain fiber u will generate an autogenous 11 beam (not shown) and a laser gain beam (not shown in 201110488). The first grating 13 totally reflects the self. A radiation beam and the laser gain beam are incident on the second grating 16 to resonate between the first grating 13 and the second grating 16. After the resonant laser light (not shown) passes through the second grating 16, a portion of the output portion reflects and continues to resonate. The formation of a laser pulse begins with the amplification of the auto-light beam. The auto-radiation beam is amplified by the gain fiber 14, and the saturated absorption fiber 15 is made smaller by being absorbed, so that the auto-radiation beam is initially suppressed and cannot be amplified into a laser. However, when the saturated absorption fiber 15 reaches the absorption residual state, it is no longer absorbed, and at this time, the self-radiation is rapidly amplified by the gain fiber 14 in the return resonance to form the laser pulse 17. A disadvantage of the all-fiber passive Q-switched laser system is that the excitation source 11 provided must be amplitude-variable to produce a continuous laser pulse. Referring to the second figure, it is a schematic diagram of a conventional all-fiber saturated absorption Q-switched laser system. The all-fiber saturated absorption Q-switched laser system 2 has a structure of a ring-shaped resonant cavity 27, which includes a gain fiber 21, a saturated absorption fiber 22, and an optical circulator. 23. A fiber grating 24, a laser pulse 28, a gain region Rg, and a light intensity | degree enhancement region Re. The gain fiber 21 is disposed in the gain region RG of the all-fiber saturated absorption q-switching laser system 2'. The gain fiber 21 is excited by an excitation light source 25 to generate a laser beam output to the optical circulator 23. The optical circulator 23 receives the laser light output by the gain fiber 21. The optical circulator 23 controls the resonance direction of the ring resonator 27 so that the direction of the light can only advance from the end point A of the optical circulator 23 to The end point B, and the progress from the end point B to the end point, the optical circulator 23 can simultaneously exclude the excitation light source 25 to prevent the saturated absorption fiber 22 from absorbing the excitation light source 25. The fiber grating 24 is disposed on an output side of the optical circulator 23, and the optical fiber is ^201110488
與該賴環器23共同伽而形成該全光纖式飽和吸收Q 二、雷射魏20之該紐度強化區域。觀纖光柵％反射Together with the looper 23, the all-fiber-enhanced region of the all-fiber saturated absorption Q2 and the laser-week 20 is formed. Fiber grating grating % reflection
义P刀的雷射光，使其透過該光循環器23的作用（從端點B 月’j進至端點c)❿反射回到該環型共振腔27，並輸出另一部分 的雷射光。 。。該全光纖式飽和吸收q切換雷射系統2()還包含一分波多 器26丨„又於該激發光源25之輸出側以利於將該激發光源 輕合進入該增益光纖21。該增益光纖21接收自該分波多工 器26所導入之雷射光束而產生一自體輻射光束（未顯示）與一 田射增盈光束（未顯示）輸出至該光循環器23，該飽和吸收光 纖22吸收自光循每器23端點a前進至端點β的雷射光。經該 飽和吸收光纖22魏-辦愤，剩下部份的光由該光纖光桃 24反射-定比例的雷射光束（未顯示），該定比例的雷射光束 透過光循環器23的端點Β至端點c之路徑而將蚊比例的雷 射光束反射酬輯财_ 27骑共振，重複級該分波 夕工器26進入該增益光纖26而從該光循環器23回到該分波 多工器26的程序，該光纖光栅24輪出剩餘比例之另一部分雷 射光。當該飽和吸收光纖22到達吸從飽和狀態肖，即不再吸 收來自該光循環H 23的雷射光’而以高絲度產生該雷射脈 衝28。然而該全光纖式飽和吸收q切換雷射系統2()的缺點是： 該激發光源25必縣振幅可調變式的才能產生連續的雷射脈 衝。 因此-種全被動式全光纖雷射系統被提出，只需要提供一 固定振幅的激發光源就可以產生一連續雷射脈衝。 201110488 【發明内容】 本發明為-種被動式光纖雷射系統，目的在於只需要提供 一固定振幅的激發光源就可以產生一連續雷射脈衝。 根據上述構想，該被動式絲雷射系統包含—統、一增 益光纖、及-切換器。該光源產生一固定振幅光束，該光源^ 含-第-部分與-第二部分。該增錢纖魏該第二部分，用 以產生一雷射脈衝。該切換器同時吸收該第一部分與放大該雷 射脈衝。該固定振幅激發光源先經過該切換器，而被該切換= • 吸收該第一部分後，剩下部分為該第二部分，當該雷射脈衝經 過該切換器並且被放大後，該切換器迅速降低該第二部分。 根據上述構想’翻t賦光纖雷射彡、雜展成具有環型处 構的雷射共振腔，該被動式光纖雷射系統包含一光源、一雷^ 共振腔、及-增益器。該光源產生一固定振幅光束，該光:包 含:第-部分與-第二部分。該雷射共振腔為一駐波雷射腔及 環型雷射腔其中之一。該雷射共振腔吸收該第二部分，用以 產生雷射脈衝。該增盈器同時吸收該第一部分與放大該雷射 脈巧。該固定振幅激發光束先經過該增益器而被該增益器吸收 _ 該?Τ部^^ ’剩下部分*該第二部分，當該雷射脈衝經過該 增盈器並且被放大後，該增益器迅速降低該第二部分。 依據上述構想，一種產生連續雷射脈衝的方法被提出，該 ^法包括下列步驟：（a)提供一第一固定振幅光束。吸收該 第一固，振幅光束一第一部分。(c)吸收該第一固定振幅光束光 束的一第二部分，以產生一雷射脈衝。（d)放大該雷射脈衝以 輸出該雷射脈衝。（e)回復到一初始狀態，重複(a)〜(d)的步驟以 輸出下一個雷射脈衝。其中在步驟(d)之後，還包含下列步驟： (dl)在該雷射脈衝被激發後，提供一第二固定振幅光束。（d2) 吸收該第二固定振幅光束的一第三部分。（d3)吸收該第二固定 振幅光束的一第四部分。 201110488 加、ΐ述綠巾，料二部分為在該雷射脈输麟前該第-==收完後剩下⑽分，該細部分為在該脈衝被激 喊束雜第四部分小於該第1定減光束的^ 藉由以上職動式賴系統及其產生雷射脈衝的操作方 法，俾能達取需提供-穩定_定振喊源，就能產生連續The laser light of the P-knife is reflected back to the ring-shaped resonant cavity 27 by the action of the optical circulator 23 (from the end point B'j to the end point c), and outputs another portion of the laser light. . . The all-fiber saturated absorption q-switching laser system 2 () further includes a wavelength dividing device 26 又 and further on the output side of the excitation light source 25 to facilitate the light-integration of the excitation light source into the gain fiber 21. The gain fiber 21 Receiving a laser beam introduced from the demultiplexer 26 to generate an autoradiation beam (not shown) and a field enhancement beam (not shown) output to the optical circulator 23, the saturated absorption fiber 22 absorbing The laser light that travels from the end point a of the device 23 to the end point β. The saturated absorption fiber 22 is angered, and the remaining portion of the light is reflected by the fiber optic peach 24 - a proportional laser beam ( Not shown), the proportional laser beam passes through the end point of the optical circulator 23 to the path of the end point c, and the laser beam of the mosquito ratio is reflected to the resonance, and the repetition stage is divided into waves. The device 26 enters the gain fiber 26 and returns from the optical circulator 23 to the program of the split multiplexer 26, which rotates another portion of the remaining portion of the laser light. When the saturated absorbing fiber 22 reaches the suction saturation state Xiao, that is, no longer absorbs the laser light from the light cycle H 23 'The laser pulse 28 is generated with high filamentity. However, the all-fiber saturated absorption q-switched laser system 2 () has the disadvantage that: the excitation light source 25 must be amplitude-variable to generate continuous laser pulses. Therefore, a fully passive all-fiber laser system is proposed, which only needs to provide a fixed amplitude excitation light source to generate a continuous laser pulse. 201110488 SUMMARY OF THE INVENTION The present invention is a passive optical fiber laser system, the purpose is According to the above concept, the passive wire laser system comprises a system, a gain fiber, and a switcher. The light source generates a fixed amplitude beam, which is required to provide a fixed amplitude excitation light source. The light source ^ includes a - part - and a second part. The second part is used to generate a laser pulse. The switch simultaneously absorbs the first portion and amplifies the laser pulse. The light source passes through the switch first, and the switch is followed by: • after absorbing the first portion, the remaining portion is the second portion, when the laser pulse passes through the switch and After zooming in, the switch quickly lowers the second portion. According to the above concept, the laser fiber laser has a ring-shaped configuration, and the passive fiber laser system includes a light source. Thunder ^ resonant cavity, and - gain device. The light source generates a fixed amplitude beam, the light: comprising: a first portion and a second portion. The laser resonant cavity is a standing wave laser cavity and a ring type laser cavity One of the laser resonators absorbs the second portion for generating a laser pulse. The gainer simultaneously absorbs the first portion and amplifies the laser pulse. The fixed amplitude excitation beam passes through the gain device first. The gain is absorbed by the gainer. The remaining portion* of the second portion, the gainer rapidly lowers the second portion as the laser pulse passes through the gainer and is amplified. In accordance with the above concept, a method of generating a continuous laser pulse is proposed which includes the following steps: (a) providing a first fixed amplitude beam. Absorbing the first solid, amplitude beam of a first portion. (c) absorbing a second portion of the first fixed amplitude beam of light to produce a laser pulse. (d) Amplifying the laser pulse to output the laser pulse. (e) Reverting to an initial state, repeating the steps (a) to (d) to output the next laser pulse. Wherein after step (d), the method further comprises the steps of: (dl) providing a second fixed amplitude beam after the laser pulse is excited. (d2) absorbing a third portion of the second fixed amplitude beam. (d3) absorbing a fourth portion of the second fixed amplitude beam. 201110488 Add and repeat the green towel. The second part is the (10) point after the first -== is completed before the laser pulse is transmitted. The fourth part is smaller than the fourth part in the pulse. The first fixed-reduction beam ^ by the above-mentioned operating system and its operation method of generating laser pulses, can achieve the need to provide - stable _ fixed vibration source, can produce continuous
雷射脈衝的功效，其他的概及魏，可參_後文的實施方 式後便能得到更進一步的了解。 【實施方式】 請參閱第三® ’其為本案第—較佳實施觸提全光纖被動 切換雷射系統的示意圖。該全光纖被動切換雷射系統3〇包含 -飽和增益激發切換放大！i 31與—飽和吸㈣切換雷射系統 32。該飽和增益激發切換放大器31包含一飽和增益激發切換 • 靡PS)311與—分波多卫器（贿)31〇。該飽和吸收Q切換雷 射糸統32包含-增益光、纖321、一激發源隔離器微、一飽和 吸收Q切換器⑽S)323、_固定振幅光束33、一第三光拇 324 ^第四光柵325、及-雷射脈衝34。該飽和吸收卩切換 雷射系統32為-雷射共振腔。該增益光纖犯卜該飽和吸收q 切換器323、及該飽和増益激發切換器3ιι皆為捧斜光纖，但 該增益光纖321的截面積比其他兩個大。 、激發光源(未顯7^的輸人與該雷雛衝34的輸出皆經 過該分波多工器310。該雷射脈衝34產生的週期分為一第一 ，月間帛一，硝帛二期間、及一第四期間。該激發光源『 201110488 提供一固定振幅光束33，在一較佳實施例中，該固定振幅光 束33的波長為980奈米，且由一半導體雷射所產生（未顯示）。 該固定振幅光束33包含一第一部分（未顯示）與一第二部分 35 ’該固定振幅光束33先經過該餘和增益激發切換器Mi， 且經過了該第一期間而先被該飽和增益激發切換器311吸收 了該第一部分（未顯示）’剩下部分為該第二部份，該第二 部分35在接下來的該第二期間被該飽和吸收q切換雷射系統 32吸收。 該第二部分35經過該增益光纖321使該增益光纖321產 生一自體輻射光束（未顯示）與一雷射增益光束36，該自體輻 射光束經過該激發源隔離器322到達該飽和吸收q切換器 323 ’而被該飽和吸收Q切換器323吸收，使該自體輻射光束 強度變小該第四光拇325全反射該自體輕射光束，使其在該 弟二光柵324與該第四光柵325之間來回共振。 該激發源隔離器322的主要目的是使該飽和吸收q切換器 323不被該固定振幅光束33所影響。因為該增益光纖321為 掺斜光纖，而掺辑光纖的能隙特性使光子受激輻射出丨55〇奈 米附近波長，該激發源隔離器322可讓波長在153〇〜157〇奈米 光子通過，且可將未被該增益光纖321完全吸收的部分過濾 掉，以防止該飽和吸收q切換器323提早受到激發而喪失功能。 該雷射脈衝34的形成是從該自體輻射光束的放大開始。 該自體輻射光束在來回共振的過程中經過該增益光纖321而 且該自體輻射被放大’而經過該飽和吸收q切換器323會因被 及收而，小，使得該自體輻射光束一開始被抑制而無法放大成 雷射脈衝。但當該飽和吸收q切換器323到達吸收飽和狀態後 即不再吸收’此時該自體輻射光束會在來回共振中被該增益光r 201110488 纖321快速放大，產生該雷射增益光束36，該雷射增益光束 36經過該飽和增益激發切換器311的放大而從該分波多工器 310輸出該雷射脈衝34。 11 在該雷射脈衝34出現前，該飽和增益激發切換器3ιι被 具有波長_奈米的該固定振幅光束33激發而與該增益光纖 321 —樣呈現高增益，此時該飽和增益激發切換器311對具有 波長980奈米的該固定振幅光束33而言是低損耗。當該雷射 脈衝34被產生後，該雷射脈衝34經過該飽和增益激發切換器 311被放大，且同時增盈飽和該飽和增益激發切換器mi。所 謂增益飽和(gain saturation)，即是指增益係數被降趨為零。 在該第三期間内，該飽和增益激發切換器311對該固定振 幅光束33的該第一部分的損耗因為增益飽和的影響，瞬間由 低變高，此時稱瞬間由低變高的該第一部分為第三部分，該第 二部份即為該雷射脈衝34被激發後，該飽和增益切換器311 吸收該固定振幅光束33的部份。如此一來導致進入該增益光 纖321的該第二部分的強度在該第三期間被動地自動由高變 低，此時被降低強度的第二部分稱為第四部分，該第四部份即 為該第三部份被該飽和增益切換器311吸收後，進入該飽和吸 收Q切換雷射系統32的部份。因為該第三部份瞬間由低變高， 使該增益光纖321被激發的速度便被延緩，使得該飽和吸收q 切換器323有足夠的時間回復初始狀態，該初始狀態為該飽和 吸收Q切換器323未吸收飽和的狀態。如此一來就可以在提供 該固定振幅光束33的情況之下，該雷射脈衝34可以連續地被 產生。 該分波多工器310負責將該固定振幅光束導入，且將被放 大的該雷射脈衝34導出。經過具有波長980奈米的該固定振「 201110488 幅光束33激發後’該全光纖被動切換雷㈣統3()可連續輸出 波長為1530奈米的該雷射脈衝34，該雷射脈衝％的脈波頻 率在50Hz〜1000Hz之間、最大脈衝能量為1〇微焦耳、脈衝寬 度為50奈秒、以及最大瞬間脈衝功率可達2〇卯。 ，明參閱第四® ’其為本案第二較佳實施例，具環狀結構的 全光纖被動峨雷射系統的示意圖。該具環狀結構的全光纖被 動切換雷射系統40包含-飽和增魏發切換放大器41及一飽 和吸收Q切換環狀雷射腔42。該飽和增益激發切換放大器Μ • &含一飽和增益激發切換器411與-分波多工器410。該飽和 吸收Q切換環狀雷射腔42包含一分波多工器421、一分波多 工器422、一光循環器424、一增益光纖423、一分功率器427、 一飽和吸收Q切換器425、一第五光柵426、一固定振°幅光束 43、一雷射增益光束46、以及一雷射脈衝44。 一激發光源（未顯示）的輸入與該雷射脈衝44的輸出皆經 過該分波多工器410。該激發光源提供一固定振幅光束43，在 一較佳的實施例中，該固定振幅光束43的波長為98〇奈米， _ 且由一半導體雷射所產生（未顯示）。該固定振幅光束43包含 一第五部分(未顯示）與一第六部分45，該固定振幅光束43先 經過該飽和增盈激發切換器411而先被吸收了該第五部分（未 顯示），剩下部分為該第六部份45，該第六部分45被該飽和 吸收Q切換雷射系統42吸收。 該第六部分45進入該飽和吸收Q切換環狀雷射腔π，經 由該增益光纖423使該增益光纖423產生一自體輻射光束（未 顯示）’該自體輻射光束經過該光循環器424到達該飽和吸收 Q切換器425 ’而被該飽和吸收Q切換器425吸收，使該自體 輻射光束強度變小。該第五光柵436全反射該自體輻射光束、 11 201110488 使其在該飽和吸收Q切換環型雷射腔42内產生共振。 在該光循環器424之端.點C #輸出側妨該分功率器 7’其控制-定比例之㈣功相卿雜雷紐42進行雷 射共振’並輸出剩餘比例之雷射，例如本案較佳實施例為2〇% 的雷射功率430回到該增益光纖423再被放大，麟的雷射功 率4。29輸出至該分波多工器42卜同樣的當該飽和吸收㈣ 換器425到達吸收飽和狀態時，料再吸收來自光循環器似 的雷射光’而以高綠度產生該雷射增益光束46。 —該具環狀結構的全光纖被動切換雷射系統4〇，在一次循 環週期^諸光會_光強度強倾域&⑽該飽和吸收 Q切換器425❺次，使其平均強度達到其他區域平均強度的2 至^倍，以使該飽和魏q切換器奶快速飽和而呈透明狀， 接著產生該諸增益光束46，該雷射增益光束46經過該飽和 增益激發切換11 411再次被放大，而進域分波多工器41〇， 並且從該分波多工器41〇輪出該雷射脈衝。 在該雷射脈衝44出現前，該飽和增益激發切換器411被 具有波長980奈米的該固定振幅光束43激發而與該增益光纖 423 —樣呈現高增益，此時該飽和增益激發切換器411對具有 波長980奈米的該固定振幅光束43❿言是低損耗。當該雷射 脈衝44被產生後’該雷射脈衝44經過該飽和增益激發切換器 411被放大，且同時增益飽和該飽和增益激發切換器411。 此時該飽和增益激發切換器411對該固定振幅光束43的 該第五部分的損耗因為增益飽和的影響，瞬間由低變高。如此 一來導致進入該增益光纖423的該第六部分45的強度被動地 自動由高變低，使該增益光纖423被激發的速度便被延緩，使 12 201110488 得該飽和吸收Q切換器425有足夠的時間回復初始狀態，該初 始狀態為該飽和吸收Q切換器425未吸收飽和的狀態。如此一 來就可以在提供該固定振幅光束43的情況之下，該雷射脈衝 44可以連續地被產生。 該分波多工益410負責將該固定振幅光束導入，且將被放 大的該雷射脈衝44導出。經過具有波長980奈米的該固定振 幅光束43激發後，該具環狀結構的全光纖被動切換雷射系統 40可連續輸出波長為1530奈米的該雷射脈衝44,該雷射脈衝 44的脈波頻率在5〇Hz〜1000Hz之間、最大脈衝能量為10微焦 耳、脈衝見度為50奈秒、以及最大瞬間脈衝功率可達2〇〇界， 實驗結果與本案第一實施例相似。 經由上述兩個較佳的實施例的說明得知，只需使用固定振 幅的激發光源設備即可產生連續的該雷射脈衝34, 44，不再需 要使用調變式的激發光源。穩定的激發光源設備價格便宜並可 縮小化成電池裝置，使系統更簡易且成本更低。 綜上所述，本發明的說明與實施例已揭露於上，然其非用 來限制本發明，凡習知此技藝者，在不脫離本本發明的精神與 範圍之下，當可做各種更動與修飾，其仍應屬在本發明專利的 涵蓋範圍之内。 【圖式簡單說明】 第一圖：習用全光纖型被動式Q—切換雷射系統的示意圖； 第二圖：習用全光纖式飽和吸收Q_切換雷射系統的示意圖： 第二圖：本案第一較佳實施例全光纖被動切換雷射系統的示意 圖；及 ^ 第四圖：本案第二較佳實施例具環狀結構的全光纖被動切換雷 13 201110488 射糸統的不意圖。 【主要元件符號說明】 10:全光纖型被動式Q-切換雷射系統 11:激發光源 12:激發光束 13:第一光柵 14, 21，423:增益光纖 15:飽和吸收光纖 φ 16:第二光柵 17,28,34,44:雷射脈衝 20:全光纖式飽和吸收Q切換雷射系統 22:飽和吸收光纖 23, 424:光循環器 24:光纖光柵 30:全光纖被動切換雷射系統 31,41:飽和增益激發切換放大器 I 32:飽和吸收Q切換雷射系統 33, 43·.固定振幅光束 35:第二部份 36,46:雷射增益光束 40:具環狀結構的全光纖被動切換雷射系統 42:飽和吸收Q切換環狀雷射腔 45:第六部份 310, 410, 421，422:分波多工器(WDM) 311,411:飽和增益激發切換器(SAPS) 321,423:增益光纖 14 201110488 322:激發源隔離器 323,425:飽和吸收Q切換器(SAQS) 324:第三光柵 325:第四光柵 426:第五光柵 427:分功率器 429: 20%雷射功率 430: 80%雷射功率 φ 增益區域 RE:光強度強化區域The efficacy of the laser pulse, other general and Wei, can be further understood after the implementation of the latter. [Embodiment] Please refer to the third ® ', which is the first embodiment of the present invention - a schematic diagram of the all-fiber passive switching laser system. The all-fiber passive switching laser system 3〇 includes - saturation gain excitation switching amplification! i 31 and - saturated suction (four) switch laser system 32. The saturation gain excitation switching amplifier 31 includes a saturation gain excitation switching • 靡PS) 311 and a-demultiplexer (bribe) 31〇. The saturated absorption Q switching laser system 32 includes -gain light, fiber 321 , an excitation source isolator micro, a saturated absorption Q switch (10) S) 323, a fixed amplitude beam 33, a third optical thumb 324 ^4 Grating 325, and - laser pulse 34. The saturated absorption 卩 switching laser system 32 is a - laser resonant cavity. The gain fiber optic discards the saturable absorption q switch 323 and the saturation gain exciter switch 3 ιι are all slanted fibers, but the gain fiber 321 has a larger cross-sectional area than the other two. The excitation light source (the output of the undetected 7^ and the output of the lightning recovery 34 passes through the splitter multiplexer 310. The period generated by the laser pulse 34 is divided into a first period, the first month, the second period And a fourth period. The excitation source "201110488 provides a fixed amplitude beam 33. In a preferred embodiment, the fixed amplitude beam 33 has a wavelength of 980 nm and is generated by a semiconductor laser (not shown). The fixed amplitude beam 33 includes a first portion (not shown) and a second portion 35'. The fixed amplitude beam 33 first passes through the residual gain excitation switch Mi, and is saturated by the first period. The gain excitation switch 311 absorbs the first portion (not shown) 'the remaining portion is the second portion, and the second portion 35 is absorbed by the saturation absorption q switching laser system 32 during the next second period. The second portion 35 passes through the gain fiber 321 to cause the gain fiber 321 to generate an auto-radiation beam (not shown) and a laser gain beam 36. The auto-radiation beam passes through the excitation source isolator 322 to reach the saturation absorption q. Switcher 3 23' is absorbed by the saturated absorption Q switch 323 to make the intensity of the self-radiation beam smaller. The fourth optical thumb 325 totally reflects the self-light beam, so that the second grating 324 and the fourth grating Resonating back and forth between 325. The main purpose of the excitation source isolator 322 is to prevent the saturation absorption q switch 323 from being affected by the fixed amplitude beam 33. Because the gain fiber 321 is a doped fiber, the energy of the fiber is blended. The gap characteristic causes the photon to be excited to emit radiation at a wavelength of about 55 〇 nanometer. The excitation source isolator 322 allows photons of wavelengths to pass through 153 〇 to 157 Å, and can filter the portion not completely absorbed by the gain fiber 321 Off, to prevent the saturation absorption q switch 323 from being excited to lose function early. The formation of the laser pulse 34 begins with amplification of the autoradiation beam. The autoradiation beam passes the gain during back and forth resonance. The optical fiber 321 and the auto-radiation are amplified', and the saturated absorption q-switch 323 is small due to being received, so that the auto-radiation beam is initially suppressed and cannot be amplified into a laser pulse. And the absorption q switch 323 is no longer absorbed after reaching the absorption saturation state. At this time, the auto-radiation beam is rapidly amplified by the gain light r 201110488 in the back and forth resonance, and the laser gain beam 36 is generated. The gain beam 36 is amplified by the saturation gain excitation switch 311 to output the laser pulse 34 from the split multiplexer 310. 11 Before the appearance of the laser pulse 34, the saturation gain excitation switch 3 is enabled to have a wavelength The fixed amplitude beam 33 of the meter is excited to exhibit a high gain as the gain fiber 321 when the saturation gain excitation switch 311 is low in loss for the fixed amplitude beam 33 having a wavelength of 980 nm. When the laser pulse 34 is generated, the laser pulse 34 is amplified by the saturation gain excitation switch 311, and simultaneously saturates the saturation gain excitation switch mi. The so-called gain saturation means that the gain coefficient is reduced to zero. During the third period, the saturation gain excitation switch 311 loses the first portion of the fixed amplitude beam 33 due to the effect of gain saturation, and then instantaneously changes from low to high. For the third portion, the second portion is that after the laser pulse 34 is excited, the saturation gain switch 311 absorbs a portion of the fixed amplitude beam 33. As a result, the intensity of the second portion entering the gain fiber 321 is passively automatically changed from high to low during the third period, and the second portion of the reduced intensity is referred to as the fourth portion, and the fourth portion is After the third portion is absorbed by the saturation gain switcher 311, the portion of the saturation absorption Q switching laser system 32 is entered. Since the third portion instantaneously changes from low to high, the speed at which the gain fiber 321 is excited is delayed, so that the saturated absorption q switch 323 has sufficient time to return to the initial state, and the initial state is the saturation absorption Q switching. The 323 does not absorb the saturated state. In this way, the laser pulse 34 can be continuously generated in the case where the fixed amplitude beam 33 is provided. The split multiplexer 310 is responsible for directing the fixed amplitude beam and deriving the amplified laser pulse 34. After the fixed vibration "201110488 beam 33 excitation" having a wavelength of 980 nm, the all-fiber passive switching Ray (4) system 3 () can continuously output the laser pulse 34 having a wavelength of 1530 nm, and the laser pulse is % The pulse wave frequency is between 50Hz and 1000Hz, the maximum pulse energy is 1〇 microjoule, the pulse width is 50 nanoseconds, and the maximum instantaneous pulse power is up to 2〇卯. See the fourth® for the second comparison. A preferred embodiment of the present invention is a schematic diagram of an all-fiber passively-switched laser system having a ring structure. The all-fiber passive switching laser system 40 having a ring structure includes a saturation-enhanced switching amplifier 41 and a saturated absorption Q-switching ring. a laser cavity 42. The saturation gain excitation switching amplifier & • & includes a saturation gain excitation switch 411 and a-split multiplexer 410. The saturated absorption Q switching annular laser cavity 42 includes a wavelength division multiplexer 421, a splitter multiplexer 422, an optical circulator 424, a gain fiber 423, a power divider 427, a saturable absorption Q switch 425, a fifth grating 426, a fixed amplitude beam 43, and a laser gain Beam 46, and a laser The input of an excitation source (not shown) and the output of the laser pulse 44 pass through the splitter multiplexer 410. The excitation source provides a fixed amplitude beam 43 which, in a preferred embodiment, is fixed The amplitude beam 43 has a wavelength of 98 〇 nanometers, _ and is generated by a semiconductor laser (not shown). The fixed amplitude beam 43 includes a fifth portion (not shown) and a sixth portion 45, the fixed amplitude beam. The first portion (not shown) is first absorbed by the saturation gain excitation switch 411, and the remaining portion is the sixth portion 45. The sixth portion 45 is switched by the saturation absorption Q laser system. 42. The sixth portion 45 enters the saturated absorption Q switching annular laser cavity π, and the gain fiber 423 generates an autoradiation beam (not shown) via the gain fiber 423. The self-radiation beam passes through the light. The circulator 424 reaches the saturated absorption Q switch 425' and is absorbed by the saturated absorption Q switch 425 to make the intensity of the auto-radiation beam small. The fifth grating 436 totally reflects the auto-radiation beam, 11 201110488 In the full Resonance is generated in the absorption Q-switching ring type laser cavity 42. At the end of the optical circulator 424, the point C # output side may be controlled by the power divider 7', and the control is proportional to the (four) power phase. Shooting the resonance 'and outputting the remaining proportion of the laser. For example, in the preferred embodiment of the present invention, 2% of the laser power 430 is returned to the gain fiber 423 and then amplified, and the laser power of the 4. 4 is output to the split multiplexer. Similarly, when the saturated absorption (four) converter 425 reaches the absorption saturation state, the material is reabsorbed from the optical circulator-like laser light' to generate the laser gain beam 46 with high greenness. - the ring structure The all-fiber passive switching laser system 4 〇, in one cycle cycle ^ 亮 光 _ light intensity strong tilt domain & (10) the saturated absorption Q switch 425 times, so that its average intensity reaches the average intensity of other regions 2 to ^ Multiple times, so that the saturated Wei q switcher milk is rapidly saturated and transparent, and then the gain beams 46 are generated, and the laser gain beam 46 is amplified again by the saturation gain excitation switching 11 411, and the in-field splitting multiplexing 41〇, and from the splitter multiplexer 41 Round out the laser pulse. Before the appearance of the laser pulse 44, the saturation gain excitation switcher 411 is excited by the fixed amplitude beam 43 having a wavelength of 980 nm to exhibit a high gain as the gain fiber 423, at which time the saturation gain excitation switch 411 The fixed amplitude beam 43 having a wavelength of 980 nm is rumored to be low loss. When the laser pulse 44 is generated, the laser pulse 44 is amplified by the saturation gain excitation switch 411, and at the same time the saturation saturates the saturation gain excitation switch 411. At this time, the loss of the fifth portion of the fixed-amplitude excitation switch 411 to the fixed amplitude beam 43 is instantaneously changed from low to high due to the influence of gain saturation. As a result, the intensity of the sixth portion 45 entering the gain fiber 423 is passively automatically changed from high to low, so that the speed at which the gain fiber 423 is excited is delayed, so that the saturated absorption Q switch 425 of 12 201110488 has Sufficient time is returned to the initial state, which is a state in which the saturated absorption Q switch 425 does not absorb saturation. Thus, in the case where the fixed amplitude beam 43 is provided, the laser pulse 44 can be continuously generated. The split-wave multi-benefit 410 is responsible for directing the fixed amplitude beam and deriving the amplified laser pulse 44. After being excited by the fixed amplitude beam 43 having a wavelength of 980 nm, the all-fiber passive switching laser system 40 having a ring structure can continuously output the laser pulse 44 having a wavelength of 1530 nm, and the laser pulse 44 The pulse frequency is between 5 〇 Hz and 1000 Hz, the maximum pulse energy is 10 microjoules, the pulse visibility is 50 nanoseconds, and the maximum instantaneous pulse power is up to 2 〇〇. The experimental results are similar to the first embodiment of the present case. As is apparent from the above description of the two preferred embodiments, it is only necessary to use a fixed amplitude excitation light source device to produce a continuous laser pulse 34, 44, eliminating the need for a modulated excitation source. Stable excitation source devices are inexpensive and can be reduced to battery devices, making the system simpler and less expensive. In the above, the description and the embodiments of the present invention have been disclosed, and are not intended to limit the present invention, and those skilled in the art can make various changes without departing from the spirit and scope of the present invention. And modifications, which still fall within the scope of the present invention. [Simple diagram of the diagram] The first picture: a schematic diagram of a conventional all-fiber passive Q-switched laser system; The second picture: a schematic diagram of a conventional all-fiber saturated absorption Q_switched laser system: Second: The first case of the case DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A schematic diagram of an all-fiber passive switching laser system; and FIG. 4: The second preferred embodiment of the present invention has a ring-shaped all-fiber passive switching thunder 13 201110488. [Main component symbol description] 10: All-fiber passive Q-switching laser system 11: excitation light source 12: excitation beam 13: first grating 14, 21, 423: gain fiber 15: saturated absorption fiber φ 16: second grating 17, 28, 34, 44: laser pulse 20: all-fiber saturated absorption Q-switched laser system 22: saturated absorption fiber 23, 424: optical circulator 24: fiber grating 30: all-fiber passive switching laser system 31, 41: Saturated gain excitation switching amplifier I 32: Saturated absorption Q switching laser system 33, 43·. Fixed amplitude beam 35: Second part 36, 46: Laser gain beam 40: All-fiber passive switching with ring structure Laser system 42: saturating absorption Q switching annular laser cavity 45: sixth part 310, 410, 421, 422: splitting multiplexer (WDM) 311, 411: saturated gain excitation switch (SAPS) 321, 423: gain fiber 14 201110488 322: excitation source isolator 323, 425: saturated absorption Q switch (SAQS) 324: third grating 325: fourth grating 426: fifth grating 427: sub-power 429: 20% laser power 430: 80% laser Power φ Gain area RE: Light intensity enhancement area
1515