公开(公告)号：US5022732A

公开(公告)日：1991-06-11

申请号：US342947

申请日：1989-04-25

申请人： Helge E. Engan ,  Byoung Y. Kim ,  James N. Blake ,  Herbert J. Shaw

发明人： Helge E. Engan ,  Byoung Y. Kim ,  James N. Blake ,  Herbert J. Shaw

IPC分类号： G02B6/14 ,  G02B6/28 ,  G02F1/01

CPC分类号： G02B6/2821 ,  G02B6/14 ,  G02F1/0134

摘要： An optical fiber is subjected to a series of traveling flexural waves propagating along a length of the fiber. At least a portion of an optical signal propagating within the optical fiber in a first propagation mode is coupled to a second propagation mode. The optical signal in the second propagation mode has a frequency which is equal to either the sum of or the difference between the frequency of the optical signal in the first propagation mode and the frequency of the traveling flexural waves. The frequency of the optical signal in the second propagation mode is shifted upward or downward from the frequency of the optical signal in the first propagation mode as determined by the direction of propagation of the first optical signal with respect to the direction of propagation of the traveling flexural waves, and as also determined by whether the phase propagation velocity of the optical signal in the first propagation mode is greater than or less than the propagation velocity of the optical signal in the second propagation mode. An acoustic wave is induced in a generator having a gradual tapered cross-section. The generator preferably has the shape of a horn and is coaxially mounted with said optical fiber, so as to suppress the acoustic wave induced in the optical fiber in the reverse direction.

摘要翻译： 光纤经受沿纤维长度传播的一系列行进弯曲波。 以第一传播模式在光纤内传播的光信号的至少一部分耦合到第二传播模式。 第二传播模式中的光信号具有等于第一传播模式中的光信号的频率与行进的弯曲波的频率的和之和的频率的频率。 第二传播模式中的光信号的频率从第一传播模式中的光信号的频率向上或向下偏移，由第一光信号相对于传播的传播方向的传播方向确定 弯曲波，并且还根据第一传播模式中的光信号的相位传播速度是否大于或小于第二传播模式中的光信号的传播速度来确定。 在具有渐变锥形截面的发生器中感应出声波。 发电机优选具有喇叭形状并且与所述光纤同轴安装，以便抑制在相反方向上在光纤中感应的声波。

公开(公告)号：US06904188B1

公开(公告)日：2005-06-07

申请号：US10072511

申请日：2002-02-05

申请人： Seok-Hyun Yun ,  In-Kag Hwang ,  Kwan Il Lee ,  Hyo-Sang Kim ,  Pavel G. Polynkin ,  Helge E. Engan ,  Wayne V. Sorin

发明人： Seok-Hyun Yun ,  In-Kag Hwang ,  Kwan Il Lee ,  Hyo-Sang Kim ,  Pavel G. Polynkin ,  Helge E. Engan ,  Wayne V. Sorin

IPC分类号： G02B6/36 ,  G02F1/11 ,  G02F1/125 ,  G02F1/335

CPC分类号： G02B6/3636 ,  G02B6/36 ,  G02F1/116 ,  G02F1/125 ,  G02F2201/02

摘要： This invention relates to an acousto-optical tunable filter generally of the kind described in U.S. Pat. No. 6,266,462. More specifically, the invention relates to a filter and its construction, the filter including a support, first and second mounts at spaced locations on the support, an optical fiber having first and second mounted portions secured to the first and second mounts respectively and a filtering section between the first and second mounted portions, a signal generator operable to generate a periodic signal, and an electro-acoustic transducer having a terminal connected to the signal generator and an actuating portion, the electric signal causing vibration of the actuating portion, and the actuating portion being connected to the filtering section so that the vibration generates a transverse wave traveling along the filtering section. The filter has an improved damper to more effectively dampen waves traveling along the filtering section.

摘要翻译： 本发明涉及一种通常在美国专利中描述的那种声光可调滤波器。 第6,266,462号。 更具体地，本发明涉及一种过滤器及其结构，该过滤器包括支撑件，位于支撑件上的间隔位置处的第一和第二安装件，光纤具有分别固定到第一和第二安装件的第一和第二安装部分， 第一和第二安装部分之间的部分，可操作以产生周期性信号的信号发生器和具有连接到信号发生器的端子和致动部分的电声换能器，引起致动部分振动的电信号，以及 致动部分连接到过滤部分，使得振动产生沿着过滤部分行进的横波。 过滤器具有改进的阻尼器，以更有效地抑制沿着过滤部分行进的波浪。

公开(公告)号：US20080132775A1

公开(公告)日：2008-06-05

申请号：US11865455

申请日：2007-10-01

申请人： Helge E. Engan ,  Kjell G. Oygarden

发明人： Helge E. Engan ,  Kjell G. Oygarden

IPC分类号： A61B5/05 ,  A61B5/00

CPC分类号： A61B8/0875 ,  A61B8/485 ,  G01S7/52036

摘要： In some aspects, the present invention provides a method of measuring bone condition using ultrasound waves. Embodiments can involve transmitting an ultrasonic signal through a portion of a bone to be measured to a receiver. The first and second harmonics of the detected signal can then be isolated. A duration difference can then be determined between (i) the detected signal or a first harmonic of the detected signal and (ii) a higher harmonic of the detected signal. Based on that duration difference, material conditions of the bone can be estimated. Methods according to the present invention can be significantly more robust and repeatable than known methods of measuring bone conditions.

摘要翻译： 在一些方面，本发明提供了一种使用超声波测量骨骼状况的方法。 实施例可以包括将超声波信号通过待测骨骼的一部分传送到接收器。 然后可以隔离检测到的信号的第一和第二谐波。 然后可以在（i）检测到的信号或检测信号的一次谐波和（ii）检测信号的较高谐波之间确定持续时间差。 基于该持续时间差，可以估计骨骼的物质状况。 根据本发明的方法可以比已知的测量骨骼状况的方法显着更强壮和可重复。