公开(公告)号：US4687993A

公开(公告)日：1987-08-18

申请号：US821610

申请日：1986-01-23

Applicant: Marc D. Mermelstein

Inventor： Marc D. Mermelstein

IPC: G01R33/032

CPC classification number: G01R33/0327

Abstract: A magnetic field sensing transducer which converts magnetic field intensity into a magnetostrictive strain and transfers that strain to an optical fiber employs a thin wall, hollow, cylindrical shell around which is wound a ribbon of an amorphous metallic magnetostrictive material. In another embodiment, the entire shell is formed by turns of the ribbon of magnetostrictive material. The optical fiber is coiled around the magnetostrictive cylinder formed by the wound ribbon and at both its ends, the optical fiber is affixed to the shell. The shell is covered at both its ends by caps and forms a thin wall resonator having three normal axisymmetric modes of vibration. The torsional vibratory mode is here of no interest because it does not appreciably couple to the optical fiber. Any one of the other two axisymmetric modes of vibration can be made dominant by selection of the appropriate length to radius ratio of the cylindrical shell. That property enables the transducer to be tuned to maximize its response to the applied dither field. The transducer is supported by a rod that extends centrally from the end caps. Strains induced by a magnetic field cause a modification in the phase of the light propagating through the optical fiber.

Abstract translation: 将磁场强度转换为磁致伸缩应变并将该应变转移到光纤的磁场感测传感器采用薄壁，中空的圆柱形外壳，围绕其缠绕非晶金属磁致伸缩材料的带。 在另一个实施例中，整个壳体由磁致伸缩材料带形成。 光纤被卷绕在由卷绕带形成的磁致伸缩筒周围，并且在其两端处将光纤固定到壳体上。 壳体的两端由盖子覆盖，并形成具有三个正常轴对称振动模式的薄壁谐振器。 扭转振动模式在这里是没有兴趣的，因为它不明显地耦合到光纤。 通过选择圆柱形壳体的适当长度与半径比可以使振动的另外两个轴对称模式中的任何一个成为主导的。 该属性使传感器能够被调整，以使其对应用的抖动场的响应最大化。 换能器由从端盖中心延伸的杆支撑。 由磁场引起的菌株会导致通过光纤传播的光的相位发生变化。

公开(公告)号：US4515473A

公开(公告)日：1985-05-07

申请号：US650229

申请日：1984-09-13

Applicant: Marc D. Mermelstein

Inventor： Marc D. Mermelstein

IPC: G01B11/16 ,  G01L1/24 ,  G01B11/18

CPC classification number: G01L1/243 ,  G01B11/18

Abstract: A signal processor is arranged to process polarized light signals obtained from a stress sensor of the type having a photoelastic element that responds to stress by causing a phase difference between components of the polarized light propagating through that element. The stress sensor provides two output beams, each of which has a different polarized component of the transmitted light. The signal processor employs a pair of photodetectors which respond to the intensities of the two polarized light beams by converting the polarized light into electrical signals. Those two electrical signals provide the inputs to a difference differentiator that provides an output proportional to the difference between the derivatives of the inputs. The two electrical output signals of the photodetectors are also applied as inputs to a multiplier whose output is related to the product of its inputs. The square root of the output of the multiplier is obtained from a square root device and is used as the divisor in a divider whose numerator is the output of the difference differentiator. The output of the divider is applied to the input of an integrator whose output is a measure of the stress imposed on the photoelastic element.

Abstract translation: 信号处理器被布置成处理从具有光弹性元件的类型的应力传感器获得的偏振光信号，所述光弹性元件通过引起通过该元件传播的偏振光的分量之间的相位差而响应于应力。 应力传感器提供两个输出光束，每个输出光束具有透射光的不同偏振分量。 信号处理器采用一对光电检测器，其通过将偏振光转换成电信号来响应两个偏振光束的强度。 这两个电信号为差分微分器提供输入，该差分微分器提供与输入的导数之间的差成比例的输出。 光电检测器的两个电输出信号也被用作输入到其输出与其输入的乘积相关联的乘法器。 乘法器的输出的平方根从平方根器件获得，并用作分频器中的除数，其分子是差分微分器的输出。 分频器的输出被施加到积分器的输入，该积分器的输出是施加在光弹元件上的应力的量度。