The risks to both mother and babies in multiple birth are many, and the cost?

The formulas which can be used for birefringent medium with a symmetric plane are derived by means of phase retard integration.

本文对流体双折射方法做了简单的回顾。用位相差积分理论导出了具有对称平面双折射介质所适用的公式。

An exact solution for the nonlinear birefringent medium model is obtained by using SO ( 3) rotation group property.

本文利用SO（3）旋转群性质得到了非线性双折射介质模型的一个严格解。

Tolerance Optimization in Birefringent Crystal Interleaver

双折射型晶体Interleaver公差分析的优化设计

Raw Material Synthesis and Characterization of YVO_4 Birefringent Crystal

双折射晶体YVO4原料的合成与表征

Raw Material Synthesis of YVO_4 Birefringent Crystal and Investigation on the Optimun Conditions

双折射YVO4晶体原料的合成及最佳制备工艺的探讨

Study of depolarization performances of white light through a dualistic birefringent crystal

二元双折射晶体复合光退偏性能的研究

Polarization-independent beam-splitter made of birefringent crystal

用双折射晶体制做偏振无关分束器

Growth and Defects Observation of YVO_4 Birefringent Crystal

钒酸钇双折射晶体生长及缺陷观察

Growth and Analysis on Completeness of YVO_4 Birefringent Crystal

YVO4双折射晶体生长及完整性分析

We present theoretical investigations of the second-and the third-order group delay dispersion caused by a tilted birefringent filter ( TBF) that is composed of a tilted birefringent plate sandwiched between two linear polarizers.

本文研究了由理想线偏振片和单轴双折射晶体波片（光轴平行波片表面）组成的双折射滤光片倾斜放置时的二阶色散和三阶色散特性。

More exact expression for phase difference provides a convenience for more accurately analyzing the characteristics of birefringent wave plate.

更精确的相位差表述为更准确地分析双折射波片的特性提供了极大的方便。

Exact expressions for phase difference in birefringent wave plate

双折射波片相位差的精确表达

A simple and practical technique for making a large size birefringent carrier plate is described.

文中还提出了一个经济实用的大尺寸载波片制作技术。

Moreover, it leads to the prediction of so-called forked eigenstates, in which a single laser eigenstate itself is split into two spatially separated orthogonally polarized branches in one part of the cavity containing an extra normal birefringent plate.

还计算了单一的激光本征态本身分裂为两个空间分离正交极化的分支，并且有在其中包含特殊双折射晶体的情况。

Numerical calculation and comparison of three Jones matrix of a birefringent plate

双折射滤波片3种琼斯矩阵的数值计算及比较

With the use of a birefringence fiber loop filter, the wavelength spacing can be adjusted by changing the length of the used birefringence fiber, which makes the laser more flexible.

改变双折射光纤环镜滤波器中保偏光纤的长度，可以实现波长间隔可变多波长激光产生，提高了多波长光纤激光器操作的灵活性和实用性。

Compensation for Thermally Induced Birefringence with Birefringent Filter in Intracavity Frequency-doubling Solid-state Lasers

双折射滤光片消除激光热致双折射的研究

The Actual Linewidth of Laser with Birefringence Filter in Oscillator

腔内有双折射滤光片的激光实际线宽

Experimental Studies on Fine Simulation of Blood Flow in Cardiovascular Modeles(ⅰ)── The measuring principle and analysing method of the dynamic flow birefringence

心血管内流场的高质量模拟实验研究（Ⅰ）&动态流体双折射测试原理与分析方法

A Study of the Pulsatile Flow Field around Artificial Heart Valves Model by Flow Birefringence Technique

用流体双折射方法研究人工心脏瓣膜的脉动流场