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1、激光专业英语1讲解教学参考书教学参考书 n1、激光和电光学激光和电光学(英文版英文版)C.C.Davis主编主编 世界图书世界图书出版公司出版公司n2、电子科学与技术专业英语电子科学与技术专业英语.光电子技术分册光电子技术分册 张爱红张爱红主编主编 哈尔滨工业大学出版社哈尔滨工业大学出版社21、New Words and phrasesn1、Wavelength 波长波长n2、Power 功率功率n3、Beam Quality 光束质量光束质量n4、Beam Diameter 光斑直径光斑直径n5、Divergence 发散角发散角n6、Power Stability 功率稳定性功率稳定性n7
2、、Power supply 电源输入电源输入n8、cooling system 冷却方式冷却方式n9、near TEM00 近基模近基模n10、Output power 输出功率输出功率n11、Repetition frequency 脉冲重复频率脉冲重复频率3n12、Pulse width 脉宽脉宽n13、Space mode 空间模式空间模式n14、Diode-pumped 二极管泵浦二极管泵浦n15、Specification 规格、说明书规格、说明书4n 气体激光气体激光 GAS LASERSn1 氦氖激光氦氖激光 He-Ne Lasersn2 金属蒸气激光金属蒸气激光 Metal V
3、apor Lasersn3 氩离子激光氩离子激光 Argon Lasersn4 氪离子激光氪离子激光 Krypton Lasersn5 二氧化碳激光二氧化碳激光(气流型气流型)CO2(Gas Flow type)Lasersn6 二氧化碳激光二氧化碳激光(脉冲脉冲,TEA型型)CO2(Pulsed,TEA)Lasersn7 二氧化碳激光二氧化碳激光(密封型密封型)CO2(Sealed tube)Lasersn8 二氧化碳激光二氧化碳激光(波导型波导型)CO2(Wave guide)Lasersn9 一氧化碳激光一氧化碳激光 CO Lasersn10 氦镉激光氦镉激光 He-Cd Lasersn
4、11 氮分子激光氮分子激光 Nitrogen Lasers5n12 准分子激光准分子激光 Excimer Lasersn13 氙分子激光氙分子激光 Xenon Lasersn 14固体激光固体激光 SOLID STATE LASERSn15 红宝石激光红宝石激光 Ruby Lasersn16半导体激光半导体激光(0.60m 带带)Semiconductor(0.60m)Lasersn17 Nd:YAG 激光激光(脉冲式脉冲式)Nd:YAG(Pulsed)Lasersn18 Nd:YAG 激光激光(连续式连续式)Nd:YAG Laser(CW)Lasersn19 Nd:YAG 激光激光(半导体激
5、光激发半导体激光激发)Nd:YAG(LD Pumped)Lasersn20染料激光染料激光 Dye Lasers6n 激光用元件激光用元件 LASER COMPONENTSn1 Q 开关开关 Laser Q-Switchesn2 激光管激光管 Laser Tubes and Boresn3 激光棒激光棒 Laser Rodsn4 激光护眼镜激光护眼镜 Safty Equipment;Goggles Glasses and Filmsn5 气体再生设备,气体填充设备气体再生设备,气体填充设备 Gas Recyclers and Gas Handling Equipmentn6 激光控制设备激光控
6、制设备 Laser Control Equipmentn7 激光用共振腔激光用共振腔 Resonators for Lasersn8激光用冷却设备激光用冷却设备 Cooling Systems for Lasersn9激光用安全设备激光用安全设备 Safty Equipment;Protective Housings7Text 2 Optical Resonatorn1 The radiation emitted by most lasers contains several discrete optical frequencies,separated from each other by f
7、requency differences which can be associated with different modes of the optical resonator.Each mode is defined by the variation of the electromagnetic field perpendicular and along the axis of the resonator.n大多数激光器发射的光都包含有几种分立的光学频率,它们彼此间的频率差各不相大多数激光器发射的光都包含有几种分立的光学频率,它们彼此间的频率差各不相同,从而使光学谐振腔产生不同的模式同,
8、从而使光学谐振腔产生不同的模式.8n2 It is common practice to distinguish two types of resonator modes:“Longitudinal”modes differ from one another only in their oscillation frequency;“transverse”modes differ from one another not only in their oscillation frequency,but also in their field distribution in a plane perp
9、endicular to the direction of propagation.n通常将谐振腔产生的模式分为两类通常将谐振腔产生的模式分为两类:“纵模纵模”与与“横模横模”,纵模彼此间的,纵模彼此间的差异仅在于它们具有不同的振荡频率差异仅在于它们具有不同的振荡频率;横模彼横模彼此间的差异除了具有不此间的差异除了具有不同的振荡频率外,而且在垂直于其传播方向的平面内,场的分布也不同的振荡频率外,而且在垂直于其传播方向的平面内,场的分布也不同。同。9n3 The symbols TEMmnq and TEMplq are used to describe the transverse and l
10、ongitudinal mode structure of a wave inside the resonator for rectangular and cylindrical coordinates,respectively.The capital letters stand for“transverse electromagnetic waves”and the first two indices identify a particular transverse mode,whereas q describes a longitudinal mode.n 人们用符号人们用符号TEM来描述
11、光学谐振腔内电磁场的变化来描述光学谐振腔内电磁场的变化.大写字母大写字母TEM表示表示“横向电磁波横向电磁波”,前两个下标表示特定的横模,前两个下标表示特定的横模,q表示纵模,表示纵模,10n4 Because resonators that are used for typical lasers are long compared to the laser wavelength,they will,in general,have a large number of longitudinal modes.Therefore,the index q which specifies the num
12、ber of modes along the axis of the cavity will be very high.The indices for the transverse modes,which specify the field variations in the plane normal to the axis,are very much lower and typically may be only the first few integers.n因为典型激光器所用的谐振腔都比激光波长要长得多,所以一般都有很多纵模因为典型激光器所用的谐振腔都比激光波长要长得多,所以一般都有很多
13、纵模.因此,因此,表示腔体轴向模数量的表示腔体轴向模数量的q的数值非常大的数值非常大.表示横模的下标值却很小,有时可能只取前几表示横模的下标值却很小,有时可能只取前几位整数位整数.。11n5 Although a resonator mode consists of a transverse and axial field distribution,it is useful to consider these two components separately because they are responsible for different aspects of laser perform
14、ance.The spectral characteristics of a laser,such as line width and coherence length,are primarily determined by the longitudinal modes,whereas beam divergence,beam diameter,and energy distribution are governed by the transverse modes.n 激光器的光谱特性,如谱线宽度和相干长度等,主要取决于纵模激光器的光谱特性,如谱线宽度和相干长度等,主要取决于纵模;而光束发散而
15、光束发散角、光束直径和能量分布等则取决于横模,角、光束直径和能量分布等则取决于横模,12n6 In general,lasers are multimode oscillators unless specific efforts are made to limit the number of oscillating modes.The reason for this lies in the fact that a very large number of longitudinal resonator modes fall within the bandwidth exhibited by th
16、e laser transition,and a large number of transverse resonator modes can occupy the cross section of the active material.n一般来说,如果没有采取特殊的措施来限制振荡模的数量,激光器就是多模振荡器。一般来说,如果没有采取特殊的措施来限制振荡模的数量,激光器就是多模振荡器。其原因在于这样的事实,即非常多的谐振腔纵模都处于激光跃迁的带宽内,而在激其原因在于这样的事实,即非常多的谐振腔纵模都处于激光跃迁的带宽内,而在激活材料的截面内,可能有很多横模活材料的截面内,可能有很多横模.。1
17、3n7 Intensity DistributionnIn an optical resonator,electromagnetic fields can exist whose distribution of amplitudes and phases reproduce themselves upon repeated reflections between the mirrors.These particular field configurations comprise the transverse electromagnetic modes of a passive resonato
18、r.n那些在两个反射镜之间来回反射,其振幅和相位分布保持不变的电磁那些在两个反射镜之间来回反射,其振幅和相位分布保持不变的电磁场才能够存在于光学谐振腔中场才能够存在于光学谐振腔中.这些特殊的场分布形成无源谐振腔的这些特殊的场分布形成无源谐振腔的横电磁模横电磁模.143.Exercisen1、Transverse modes are defined by the designation TEMnmn for Cartesian coordinates.The integers m and n represent the number of nodes of zeros of intensity.
19、In ylindricalncoordinates,the modes are labeled TEMpl and are haracterized by the number of radial nodes p and angular nodes l.n在直角坐标系中,用符号在直角坐标系中,用符号TEM表示横模,整数表示横模,整数m和和n表示在水平和垂直方向上表示在水平和垂直方向上与光轴垂直的强度零节点的数量与光轴垂直的强度零节点的数量.在圆柱坐标系中,用在圆柱坐标系中,用TEMpl表示横模,表示横模,p表表示径向节点数,示径向节点数,l表示角向节点数表示角向节点数.15n2、The hig
20、her the values of m,n,p,and l,the higher the mode order.The lowest order mode is the TEM00 mode,which has a Gaussian intensity pro its maximum on the beam axis.For modes with subscripts of 1 or 1 more,intensity maxima occur that are off-axis in a symmetrical pattern.n m,n,p,and l的数值越大,模的阶数就越高的数值越大,模的阶数就越高.最低阶模是最低阶模是TEN00模,在模,在它的光袖上有最大的高斯强度分布,对于下标为它的光袖上有最大的高斯强度分布,对于下标为1或比或比1大的模。最大的大的模。最大的强度值不在对称花样的袖上强度值不在对称花样的袖上.161718感谢您的学习感谢您的学习19谢谢观赏谢谢观赏