公开(公告)号：US06421130B1

公开(公告)日：2002-07-16

申请号：US09282009

申请日：1999-03-29

Applicant: Donald W. Phillion

Inventor： Donald W. Phillion

IPC: G01B902

CPC classification number: G01N21/03 ,  G01B9/0201 ,  G01B2290/35

Abstract: A constant volume gas cell optical phase-shifter, particularly applicable for phase-shifting interferometry, contains a sealed volume of atmospheric gas at a pressure somewhat different than atmospheric. An optical window is present at each end of the cell, and as the length of the cell is changed, the optical path length of a laser beam traversing the cell changes. The cell comprises movable coaxial tubes with seals and a volume equalizing opening. Because the cell is constant volume, the pressure, temperature, and density of the contained gas do not change as the cell changes length. This produces an exactly linear relationship between the change in the length of the gas cell and the change in optical phase of the laser beam traversing it. Because the refractive index difference between the gas inside and the atmosphere outside is very much the same, a large motion must be made to change the optical phase by the small fraction of a wavelength that is required by phase-shifting interferometry for its phase step. This motion can be made to great fractional accuracy.

Abstract translation: 特别适用于相移干涉测量的恒定体积气体电池光学移相器包含在与大气压力稍微不同的压力下的密闭体积的气氛气体。 在单元的每一端存在光学窗口，并且随着单元的长度改变，穿过单元的激光束的光程长度变化。 该电池包括具有密封件和体积平衡开口的可移动同轴管。 因为电池的体积是恒定的，所以气体的压力，温度和密度随着电池长度的变化而不会改变。 这产生了气室长度变化与穿过其的激光束光学相位变化之间的精确线性关系。 由于内部气体和外部气氛之间的折射率差异非常相似，所以必须进行大的运动以使光学相位改变相移阶段相移干涉测量所需的波长的小部分。 这个运动可以做出很大的分数精度。

公开(公告)号：US20010014191A1

公开(公告)日：2001-08-16

申请号：US09790708

申请日：2001-02-23

Inventor： Makoto Fujino ,  Nobuo Hori ,  Shigenori Nagano

IPC: G02B006/126

CPC classification number: G01B9/0201 ,  G01B2290/70

Abstract: An simlified optical configuration is acheved and, a direction discrimination function and a high resolving detection function are performed by one light receiving section. A TE mode emitted from an optical waveguide section 3 transmits through a beam splitter 5 and is guided to a measurement optical path. A TM mode emitted from the optical waveguide is reflected by the beam splitter 5 and is guided to a reference optical path. First and second null wave plates 10 and 11 are inserted in the respective optical paths, and the TE and TM modes are acted by a null wave plate while travelling forward and backward on the reference and measurement optical paths. A reference light (TM mode) is reflected by a reference reflection section 8 and transmits through the beam splitter section 5. A measurement light (TE mode) is reflected by a measurement reflection section 9 and is reflected by the beam splitter section 5. By a polarization member 12, only direction components of the polarization member 12 are extracted from the TM and TE modes, and both waves interfere, whereby a displacement is measured by a displacement measurement section 7.

公开(公告)号：US6166818A

公开(公告)日：2000-12-26

申请号：US182506

申请日：1998-10-30

Applicant: Shigenori Nagano ,  Nobuo Hori ,  Makoto Fujino

Inventor： Shigenori Nagano ,  Nobuo Hori ,  Makoto Fujino

IPC: G01B9/02 ,  G01B11/00 ,  G01D5/26

CPC classification number: G01B9/02019 ,  G01B9/0201 ,  G01B9/02022 ,  G01B9/02051 ,  G01D5/266

Abstract: An optical system is fabricated in the form of one device, so that the simplified optical system is realized. A displacement is measured with a high resolving power utilizing an interference fringe. An interference measurement probe 2 receives a coherent light from a light source section 1, and divides the coherent light into a plurality of luminous fluxes. The interference measurement probe 2 emits a plurality of irradiation luminous fluxes at different angles. The plurality of irradiation luminous fluxes form an interference fringe and the interference fringe is irradiated onto an objective 8. A light receiving section 3 is disposed at a position where a reflection luminous flux from the objective 8 interferes, and receives an interference light reflected from the objective 8, thereby outputting a light receiving signal which is converted to an electric signal. A measurement section 4 performs processing for obtaining displacement of positions of the interference measurement probe 2 and the light receiving section 3 as well as displacement of the objective 8. A control section 5 is connected to a driving section 6, and controls the driving section 6 based on a measurement result of the measurement section 4, thereby making a stage 7 move in the Z-direction. On the stage 7, the objective 8 is mounted or provided.

Abstract translation: 以一个装置的形式制造光学系统，从而实现简化的光学系统。 使用干涉条纹以高分辨率测量位移。 干涉测量探头2接收来自光源部分1的相干光，并将相干光分成多个光通量。 干涉测量探针2以不同的角度发射多个照射光束。 多个照射光束形成干涉条纹，并且干涉条纹被照射到物镜8上。光接收部分3设置在来自物体8的反射光通量干涉的位置，并且接收从该物镜8反射的干涉光 物镜8，从而输出被转换成电信号的光接收信号。 测量部分4执行用于获得干涉测量探头2和光接收部分3的位置的位移以及物镜8的位移的处理。控制部分5连接到驱动部分6，并且控制驱动部分6 基于测量部4的测量结果，从而使台7沿Z方向移动。 在平台7上安装或提供物镜8。

公开(公告)号：US6134003A

公开(公告)日：2000-10-17

申请号：US607787

申请日：1996-02-27

Applicant: Guillermo Tearney ,  Stephen A. Boppart ,  Brett E. Bouma ,  Mark Brezinski ,  Eric A. Swanson ,  James G. Fujimoto

Inventor： Guillermo Tearney ,  Stephen A. Boppart ,  Brett E. Bouma ,  Mark Brezinski ,  Eric A. Swanson ,  James G. Fujimoto

IPC: G01B11/00 ,  A61B1/00 ,  A61B3/10 ,  A61B3/12 ,  A61B5/00 ,  A61B5/103 ,  A61B8/12 ,  A61B10/00 ,  A61M25/00 ,  G01B9/02 ,  G01B11/02 ,  G01B11/12 ,  G01B11/24 ,  G01J1/00 ,  G01N21/17 ,  G01N21/35 ,  G01N21/47 ,  G02B5/18 ,  G02B27/44 ,  G11B7/00 ,  G11B7/005 ,  G11B7/125 ,  G11B7/24 ,  H01S5/14

CPC classification number: B82Y15/00 ,  A61B1/00096 ,  A61B1/00172 ,  A61B1/00183 ,  A61B3/102 ,  A61B5/0064 ,  A61B5/0066 ,  A61B5/0075 ,  A61B5/0084 ,  A61B5/445 ,  A61B5/6852 ,  G01B11/00 ,  G01B11/026 ,  G01B11/12 ,  G01B11/2441 ,  G01B9/02002 ,  G01B9/02004 ,  G01B9/02007 ,  G01B9/0201 ,  G01B9/0205 ,  G01B9/02091 ,  G01J1/00 ,  G01N21/4795 ,  G02B5/1828 ,  G11B7/005 ,  G11B7/127 ,  A61B2562/0242 ,  A61B3/1005 ,  G01B2290/65 ,  G01B2290/70 ,  G11B2007/0013 ,  G11B7/24 ,  H01S5/141

Abstract: An imaging system for performing optical coherence tomography includes an optical radiation source; a reference optical reflector; a first optical path leading to the reference optical reflector; and a second optical path coupled to an endoscopic unit. The endoscopic unit preferably includes an elongated housing defining a bore; a rotatable single mode optical fiber having a proximal end and a distal end positioned within and extending the length of the bore of the elongated housing; and an optical system coupled to the distal end of the rotatable single mode optical fiber, positioned to transmit the optical radiation from the single mode optical fiber to the structure and to transmit reflected optical radiation from the structure to the single mode optical fiber. The system further includes a beam divider dividing the optical radiation from the optical radiation source along the first optical path to the reflector and along the second optical path; and a detector positioned to receive reflected optical radiation from the reflector transmitted along the first optical path and reflected optical radiation transmitted from the structure along the second optical path. The detector generates a signal in response to the reflected optical radiation from the reference reflector and the reflected optical radiation from the structure, and a processor generating a image of the structure in response to the signal from the detector. The system provides both rotational and longitudinal scanning of an image.

Abstract translation: 用于执行光学相干断层摄影的成像系统包括光辐射源; 参考光学反射器; 通向参考光反射器的第一光路; 以及耦合到内窥镜单元的第二光路。 内窥镜单元优选地包括限定孔的细长壳体; 可旋转的单模光纤，其具有定位在所述细长壳体的所述孔的长度内并延伸所述细长壳体的所述孔的长度的近端和远端; 以及耦合到可旋转单模光纤的远端的光学系统，定位成将光辐射从单模光纤传输到结构，并将反射的光辐射从结构传输到单模光纤。 该系统还包括一个光束分配器，将沿着第一光路的光辐射源的光辐射分成沿着第二光路; 以及检测器，其被定位成接收来自沿着第一光路传输的反射器的反射光辐射以及沿着第二光路从结构传输的反射光辐射。 检测器响应于来自参考反射器的反射光辐射和来自结构的反射光辐射产生信号，以及响应于来自检测器的信号产生结构图像的处理器。 该系统提供图像的旋转和纵向扫描。

公开(公告)号：US5991033A

公开(公告)日：1999-11-23

申请号：US933228

申请日：1997-09-18

Applicant: Philip D. Henshaw ,  Robert F. Dillon

Inventor： Philip D. Henshaw ,  Robert F. Dillon

IPC: G01B9/02

CPC classification number: G01B9/0201 ,  G01B9/02002 ,  G01B9/02014 ,  G01B9/0207 ,  G01B9/02071 ,  G01B9/02072 ,  G01B2290/60 ,  G01B2290/70

Abstract: An improved interferometer measuring system that corrects for errors in the determination of the position of a measurement reflector along a measurement path due to the presence of an atmosphere (e.g. atmospheric turbulence) along the path is disclosed. The system includes a two-wavelength interferometer for measuring the atmosphere and a basic length interferometer for a basic measurement of a change in position of the measurement reflector. A calibration procedure for correcting the basic measurements made by the basic length interferometer uses first and second correction coefficients related to the average refractivity of the atmosphere and the change in the refractivity of the atmosphere, respectively. The coefficients can be determined by interferometric measurements or from a combination of interferometric measurements and data from an atmospheric sensor(s), including a humidity sensor. The two-wavelength interferometer can include a pulsed laser source, a compact reference path element, and path length adjustment element. An algorithm is disclosed for efficiently determining the phase difference between the two beams of the two-wavelength interferometer. Beam combining techniques and apparatus for combining the beams of the two-wavelength interferometer and the basic length measurement interferometer while preserving the polarization of the laser beams are also disclosed. The data obtained from the two-wavelength interferometer can be corrected, based on measurements made by the basic length interferometer, for aging due to the movement of the reflecting mirror subsequent to measurement of the atmosphere by the two-wavelength interferometer.

Abstract translation: 公开了一种改进的干涉仪测量系统，其校正由于沿路径的气氛（例如大气湍流）的存在而沿测量路径确定测量反射器的位置的误差。 该系统包括用于测量大气的双波长干涉仪和用于测量反射器的位置变化的基本测量的基本长度干涉仪。 用于校正基本长度干涉仪进行的基本测量的校准过程分别使用与大气的平均折射率相关的第一和第二校正系数和大气的折射率的变化。 系数可以通过干涉测量或来自大气传感器（包括湿度传感器）的干涉测量和数据的组合来确定。 双波长干涉仪可以包括脉冲激光源，紧凑参考路径元件和路径长度调节元件。 公开了一种用于有效地确定双波长干涉仪的两个波束之间的相位差的算法。 还公开了用于组合双波长干涉仪的光束和基本长度测量干涉仪同时保持激光束的偏振的光束组合技术和装置。 根据基本长度干涉仪的测量，可以根据双波长干涉仪测量气氛后的反射镜的移动来校正从双波长干涉仪得到的数据。

公开(公告)号：US5903350A

公开(公告)日：1999-05-11

申请号：US99553

申请日：1998-06-18

Applicant: Ira Jeffery Bush ,  Allen Curtis Cekorich

Inventor： Ira Jeffery Bush ,  Allen Curtis Cekorich

IPC: G01B9/02 ,  G01J9/02

CPC classification number: G01B9/02079 ,  G01B9/0201 ,  G01B9/02083 ,  G01J9/02

Abstract: An apparatus and method is presented to provide wide dynamic range measurements of the input phase to an interferometer using a phase generated carrier especially useful utilizing time multiplexing to demodulate a series of interferometers. A modulation drive output is provided by the invention and maintained under operation at the optimum amplitude by an internal feedback loop. The resulting highly stable system can be fabricated from an analog to digital converter, a digital signal processor, and a digital to analog converter making low cost open loop demodulators a reality.

Abstract translation: 提出了一种装置和方法，以使用使用时间多路复用来解调一系列干涉仪的特别有用的相位产生载波，向干涉仪提供输入相位的宽动态范围测量。 调制驱动输出由本发明提供并通过内部反馈回路保持在最佳振幅下工作。 所产生的高度稳定的系统可以由模数转换器，数字信号处理器和数模转换器制成，从而实现低成本的开环解调器。

公开(公告)号：US5459571A

公开(公告)日：1995-10-17

申请号：US189931

申请日：1994-02-01

Applicant: Ehrhard Dammann ,  Juergen Bauer

Inventor： Ehrhard Dammann ,  Juergen Bauer

IPC: G01B9/02 ,  G01J1/44 ,  G01J9/02 ,  G01J9/04

CPC classification number: G01B9/02051 ,  G01B9/0201 ,  G01B9/02028 ,  G01B9/02083 ,  G01J9/02 ,  G01B2290/45 ,  G01J2001/4242 ,  G01J2009/0249 ,  G01J9/04

Abstract: A phase-modulated interferometer has improved control and signal processing. Superimposition signals capable of evaluation in a phase-modulated interferometer without a complicated sawtooth control of the phase modulator are attained, in that two sinusoidal control signals which have modulation frequencies (.omega..sub.1, .omega..sub.2) and are rigidly coupled with respect to phase and frequency are applied to the known phase modulator and a cosine signal which is used in a conventional manner for evaluating the phase displacement is filtered of the superimposition signal generated in the interferometer by an electronic bandpass filter. At the filter frequency (.omega..sub.F) of the bandpass filter, an odd-number harmonic and an even-number harmonic of the two modulation frequencies (.omega..sub.1, .omega..sub.2) have the same frequency, when the amplitudes (.phi..sub.1, .phi..sub.2) of the control signals satisfy the condition for the suitable operating point of the phase modulator. The improvement has application to phase-modulated interferometers, in particular, for precision distance measuring devices, preferably by the heterodyne evaluating method.

Abstract translation: 相位调制干涉仪具有改进的控制和信号处理。 获得能够在相位调制干涉仪中进行评估的叠加信号，无需对相位调制器进行复杂的锯齿控制，因为具有调制频率（ω1，ω2）并相对于相位和频率刚性耦合的两个正弦控制信号 应用于已知的相位调制器，并且以传统方式用于评估相位位移的余弦信号通过电子带通滤波器对在干涉仪中产生的叠加信号进行滤波。 在带通滤波器的滤波器频率（ω-F）下，两个调制频率（ω1，ω2）的奇数谐波和偶数谐波具有相同的频率，当幅度（phi 1，phi 2 ）的控制信号满足相位调制器的合适工作点的条件。 该改进适用于相位调制干涉仪，特别是用于精密距离测量装置，优选地通过外差评估方法。

公开(公告)号：US5080490A

公开(公告)日：1992-01-14

申请号：US527509

申请日：1990-05-23

Applicant: Paul K. Manhart

Inventor： Paul K. Manhart

IPC: G01B9/02 ,  G01B11/255

CPC classification number: G01B9/0201 ,  G01B11/255 ,  G01B9/02011 ,  G01B9/02019 ,  G01B9/02027 ,  G01M11/005 ,  G01B2290/15 ,  G01B2290/70

Abstract: A system for monitoring the configuration of a surface (e.g., a segmented parabolic surface) using orthogonally placed retroreflectors at sets of points A, B and C dispersed throughout the surface with a stationary halfwave plate HWP in the front of the one retroreflector at a corner point C and a rotating halfwave plate RHWP over a source of linearly polarized coherent light, thereby causing the direction of linear polarization to continuously rotate through 360.degree. and causing light returned by the retroreflector at point C to be continuously phase shifted through 360.degree. relative to light returned by retroreflectors at points A and B. The returned light from each set of points A. B and C is focused onto a bed-of-nails (BON) phase grating diagonally oriented with respect to the orthogonal orientation of the incident beams from retroreflectors A, B and C, thereby causing overlap in the light from points A and C and from points B and C to produce interferometric signals AC and BC. Any change in phase of the interferometric signals AC and BC indicates both the magnitude and direction of any change in the position of the retroreflector at point C relative to retroreflectors at points A and B.

Abstract translation: 一个系统，用于使用正交放置的回射器在一组分布在整个表面上的点A，B和C中的一个表面（例如，分段的抛物线表面）的配置，该固定半波片HWP位于一个后向反射器的前部的角部 点C和旋转半波片RHWP在线偏振相干光源上，从而使线偏振方向连续旋转360度，并使由点反射器返回的光在C点连续相移360度相对于 点A和B由后向反射器返回的光。来自每组点A.B和C的返回光聚焦到相对于入射光束的正交取向对角定向的指甲（BON）相位光栅上 后向反射器A，B和C，从而在来自点A和C以及从点B和C的光中引起重叠以产生干涉信号AC和BC。 干涉测量信号AC和BC的任何相位变化都指示回归反射器在点C相对于后点反射器在点A和B处的位置的任何变化的大小和方向。

公开(公告)号：US4844616A

公开(公告)日：1989-07-04

申请号：US200262

申请日：1988-05-31

Applicant: Murlidhar V. Kulkarni ,  William H. Lancaster, Jr.

Inventor： Murlidhar V. Kulkarni ,  William H. Lancaster, Jr.

IPC: G01B9/02 ,  G01J9/02 ,  G01N21/88 ,  G01N21/95

CPC classification number: G01B9/0201 ,  G01B9/02048 ,  G01B9/02057 ,  G01N21/9501 ,  G01N21/9506 ,  G01B2290/70 ,  G01J2009/0265 ,  G01N2021/178

Abstract: The invention is a method for detecting both surface topography and defect presence using an AC interferometer. Surface topography measurements are maximized by adjusting the signal voltage of the light modulator to a relative phase-sensitive value. Defect detection is maximized by adjusting the signal voltage of the light modulator to a relatively phase-insensitive value. This method not only allows for heretofore unknown defect detection by an AC interferometer but, because the signal voltage can be switched electronically, permits both observations to be taken at a high speed and for many points of a specimen, thereby making the method suitable for the manufacturing environment. More specifically, the method would be applicable to both optical disk and microchip manufacturing.

Abstract translation: 本发明是使用AC干涉仪检测表面形貌和缺陷存在的方法。 通过将光调制器的信号电压调整到相对相敏值来最大化表面形貌测量。 通过将光调制器的信号电压调整到相对不敏感的值来最大化缺陷检测。 该方法不仅能够通过AC干涉仪进行未知的未知缺陷检测，而且由于可以电子地切换信号电压，因此允许以高速度和样本的多个点进行观察，从而使该方法适合于 制造环境。 更具体地，该方法将适用于光盘和微芯片制造。

公开(公告)号：US11852474B2

公开(公告)日：2023-12-26

申请号：US17264165

申请日：2019-07-30

Applicant: The General Hospital Corporation

Inventor： Benjamin J. Vakoc ,  Norman Lippok

IPC: G01B9/02 ,  G01B9/02001 ,  G01B9/02091 ,  G06T7/00

CPC classification number: G01B9/0201 ,  G01B9/02008 ,  G01B9/02091 ,  G06T7/0012 ,  G06T2207/10101 ,  G06T2207/30004

Abstract: A method including: scanning a sample over a period of time using an electro-magnetic radiation source, the period of time including a first time period and a second time period, a sample portion of the electro-magnetic radiation source being directed to the sample in a sample arm of an optical interferometric system, and a reference portion of the electro-magnetic radiation source being directed to a reference arm of the optical interferometric system; applying, using a phase modulator, a phase shift comprising a first phase shift and a second phase shift to at least one of the reference portion or the sample portion of the electro-magnetic radiation source, the first phase shift being applied during the first time period and the second phase shift being applied during the second time period, the second phase shift having a difference of 90 degrees from the first phase shift; acquiring in-phase data based on a first interference between first backscattered electro-magnetic radiation during the first time period and the at least one of the reference portion or the sample portion subjected to the first phase shift; acquiring quadrature data based on a second interference between second backscattered electro-magnetic radiation during the second time period and the at least one of the reference portion or the sample portion subjected to the second phase shift; and determining a complex interference signal based on the in-phase data and the quadrature data.