球面

The computation analysis indicates that increasing the aperture of the concave focusing transducer, decreasing it's geometric focal length or raising it's central working frequency can improve the transverse and axial resolutions of the system simultaneously, but changing the dividing proportion of the transducer affects the two kinds of resolution differently. On compromisingly considering several factors including the exciting mode, the focusing ability and the radiation force effect, the concave focusing transducer should be divided into two equal-area parts.

计算研究表明：增大凹球面换能器的口径、减小几何焦距和提高中心频率均可以提高系统的侧向分辨率和轴向分辨率；但改变凹球面换能器的分割比例对两种分辨率影响不尽相同综合考虑超声换能器激励、聚焦性能以及产生的辐射力效果等因素，则换能器应按等辐射面积原则分割为宜。

And this paper also shows the structure and parameters of the optical system. The Xenon light of super high voltage is used as interferential source. The position of it is on the focus of the reflector of ellipsoid surface. After reflecting, its lights form a collective point . This point and objective focus of collimation lens are superposition. Though the collimation lens, the beam of light become parallel lights. Then though the Coude Reflector and radiation system of special prism, the lights become a beam of light with 3 ° emanative angle.

该光学系统选用超高压氙灯作光源，使其位于椭球面反射镜的一个焦点上，发出的光线经椭球面反射后所形成的汇聚点与准直负透镜组的物方焦点重合，光束经准直系统后变为平行光束，此平行光束再经库德反射镜和特殊发散棱镜系统，形成具有3°发散角的发散光束，用来干扰敌方设备。

In addition, the remanent magnetization vector field can not be transformed into potential field in general.

对地磁场的观测是在地表或卫星高度这样的球面上完成的，且岩石层的剩余磁化强度矢量场一般不能转换为位势场，因此需要研究球面各向同性随机矢量场。

To improve the performance of zoom systems and achieve a good imaging quality in WFOV, and to simplify the mechanical structure for the convenience of design, process and adjustment, a design concept that combines the conventional spheric optics with the aspheric optics was introduced in the design of zoom lens.

为提高变焦距系统的工作性能，使其在大视场时仍具有良好的像质，且系统结构简单，易于机械设计、加工及装调，在设计中引入了传统球面光学设计与非球面相结合的设计思想。

The mathematics description of the non-spherical lens is the most important problem for the beam shaping system design. A numerical simulating method and its precision analysis are given, and the results indicate that this method is simple, and can be used for the design of LD beam collimating system with non-spherical lens.

非球面柱透镜曲面的数学描述是人们目前关注较多的问题之一，作者使用数值拟合的方法，对其进行了数值拟合并给出了精度分析，结果表明：该方法简单、直观，能够完全满足特定精度的要求，从而可以方便地用于非球面柱透镜的分析和设计。

Though the opacified lens is replaced by a crystal clear optics during the cataract surgery, the disturbance of the compensatory effect of nature lens to positive corneal spherical aberration has been made by the conventional spherical intraocular lens.

然而白内障手术去除了混浊的水晶体，但是所植入的传统球面水晶体虽然提供了透明无瑕的光学区，却忽略了角膜所产生的高阶像差，尤其是球面像差。

Geographic Distance and Azimuth Calculat - This article describes in detail the spherical distance and azimuth calculations and also provides sample code for three different approaches to distance calculations: one for a spherical model, and two for ellipsoid models

这个项目详细地描述了球面距离和azimuth的计算方法，提供了三种不同的方法来进行距离计算：一个用于球面模型，其它两个用于椭球模型。

First, full-tetrafluoroethane Yixi F4 corrosion-resistant face-off valve folder, Valve structure for the separated, the use of F4 will be lining circle Valve package lining, the lining between the ring and the valve used to do back high-elastic rubber lining, Lining laps and a spherical valve plate sealed disc for the whole package tetrafluoroethane sealed structure.

产品说明书一、全聚四氟乙稀F4耐腐蚀球面对夹蝶阀，阀体结构为分体式，其使用F4衬圈将阀体包衬，衬圈和阀体之间采用高弹橡胶做靠背衬，衬圈和阀板采用球面密封，阀板为全包四氟密封结构。

The lens axicon is based on the use of the spherical aberration of the mirror surfaces,which is inexpensive and easy to manufacture into a element with large apertures as compared with diffractive axicons,refractive cone axicons,and earlier lens axicons with aspheric surfaces;the opaque disk can offer the Bessel beams with long non-diffracting distances,and the diameter of the central peak is adjusted by choosing the focal length of the collimating lens;the tunable fluidic conical lens is a new device for generating Bessel beams,which can obtain the Bessel beams with different parameters by varying the refractive indexes of the solution which is filled in the device.

双透镜轴棱锥法主要基于透镜球面像差的运用，与衍射轴棱锥、折射轴棱锥和早期的非球面轴棱锥相比，具有加工简单、便宜，易于制作大尺寸的特点；不透明障碍物法得到的贝塞尔光束具有很长的无衍射距离，其直径可通过选择不同焦距的准直透镜来得到调节；可调流体轴棱锥是一种产生贝塞尔光束的新型器件，它可以很容易地通过改变注入器件的液体的折射率来得到不同参量的贝塞尔光束。

The requirement of machining technology of aspheric surface optics parts by NC machine with Nanosys--300 aspheric surface ultraprecision compound machining system for single point diamond turning is introduced.

介绍了用金刚石单点车削的方法在&Nanosys--300非球面曲面超精密复合加工系统&数控机床上加工非球面曲面类光学零件时对加工工艺的要求。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。