公开(公告)号：US20120154780A1

公开(公告)日：2012-06-21

申请号：US13315957

申请日：2011-12-09

Applicant: Frank C. Demarest

Inventor： Frank C. Demarest

IPC: G03B27/58 ,  G06F19/00 ,  G01B11/14 ,  G01D5/347

CPC classification number: G01D5/24476 ,  G01D5/38 ,  G03F7/70775

Abstract: Methods and apparatuses for performing the same, where the methods include obtaining, from an interferometer, a time-varying interference signal S(t) based on a combination of a first beam and a second beam, the first beam being diffracted from an encoder scale, in which at least one of the encoder scale and the interferometer is moveable with respect to the other, obtaining one or more error correction signals based on one or more errors that modify the time-varying interference signal S(t), and outputting information about a change in a position of the encoder scale relative to the interferometer based on the time-varying interference signal S(t) and the one or more error correction signals.

Abstract translation: 用于执行相同的方法和装置，其中所述方法包括从干涉仪获得基于第一光束和第二光束的组合的时变干扰信号S（t），所述第一光束从编码器刻度 ，其中所述编码器标尺和所述干涉仪中的至少一个相对于另一个可移动，基于修改所述时变干扰信号S（t）的一个或多个错误获得一个或多个纠错信号，并输出信息 关于基于时变干扰信号S（t）和一个或多个纠错信号的编码器刻度相对于干涉仪的位置的变化。

公开(公告)号：US5767972A

公开(公告)日：1998-06-16

申请号：US658088

申请日：1996-06-04

Applicant: Frank C. Demarest

Inventor： Frank C. Demarest

IPC: G01B9/02 ,  G01B11/00 ,  G01J3/45 ,  G01J9/02

CPC classification number: G01J9/02 ,  G01J3/45

Abstract: An improved method and apparatus for compensating for differences in the data age of the measurements among measurement axes in an interferometer (18), such as a heterodyne interferometer, in which known values of time delay occur in the measurement (34, 38, 38a, 41 and 42) and reference signal (44) paths. A time value is measured (52) for the signal transmission over these paths for a given clock (48) period interval and the measured time value (52) is adjusted (56) for the given interval against the known time delay for compensating for the data age. The known time delay is subtracted from the measured time value for providing the adjusted time value (60) for the given interval. The adjusted time value (60) is converted into a phase measurement, and this phase measurement is converted into the dynamic interferometric position measurement (64, 68) for providing a position measurement (72, 74) independent of any velocity of movement of the object whose position is being measured and having reduced data age differences between the signal paths providing the measurement.

Abstract translation: 一种改进的方法和装置，用于补偿在诸如外差干涉仪之类的干涉仪（18）中的测量轴之间测量的数据年龄差异，其中在测量中发生已知的时间延迟值（34,38,38a， 41和42）和参考信号（44）路径。 对于给定时钟（48）周期间隔，在这些路径上的信号传输的时间值被测量（52），并且针对给定间隔的测量时间值（56）针对已知的时间延迟进行调整（56），以补偿 数据时代。 从测量的时间值中减去已知的时间延迟，以便在给定间隔内提供经调整的时间值（60）。 经调整的时间值（60）被转换为相位测量，并将该相位测量转换成动态干涉测量位置测量（64,68），用于提供独立于对象的任何移动速度的位置测量（72,74） 其位置正在被测量并且具有减小提供测量的信号路径之间的数据年龄差异。

公开(公告)号：US4332475A

公开(公告)日：1982-06-01

申请号：US156050

申请日：1980-06-03

Applicant: Frank C. Demarest

Inventor： Frank C. Demarest

IPC: G01B11/02 ,  G01B11/10

CPC classification number: G01B11/028 ,  G01B11/105

Abstract: An electro-optical sensor is described which provides a high resolution measurement of the location of the edge of an object. By passing the electrical pulse produced by an edge sensor into a multiply tapped delay line the location of the edge of an object can be measured with high resolution.

Abstract translation: 描述了一种提供物体边缘位置的高分辨率测量的电光传感器。 通过将由边缘传感器产生的电脉冲传递到多重抽头延迟线中，可以以高分辨率测量对象边缘的位置。

公开(公告)号：US07542147B2

公开(公告)日：2009-06-02

申请号：US11605855

申请日：2006-11-29

Applicant: Frank C. Demarest

Inventor： Frank C. Demarest

IPC: G01B9/02 ,  G01D1/00 ,  G06F15/00

CPC classification number: G01B9/02027 ,  G01B9/02007 ,  G01B9/02083 ,  G01B2290/45 ,  G01B2290/70

Abstract: A method is disclosed including conditioning a measurement signal from an interferometer, said conditioning characterized by one or more conditioning parameters; measuring a plurality of values for the conditioned measurement signal; providing one or more values indicative of the conditioning parameters; determining an adjustment value at each measured value of the conditioned measurement signal based on the one or more of the measured values indicative of the conditioning parameters; and adjusting a measured value of the measurement signal according to the adjustment value.

Abstract translation: 公开了一种方法，其包括对来自干涉仪的测量信号进行调节，所述调理特征在于一个或多个调节参数; 测量所述经调节的测量信号的多个值; 提供指示所述调节参数的一个或多个值; 基于表示调节参数的一个或多个测量值，确定经调节的测量信号的每个测量值的调整值; 以及根据调整值调整测量信号的测量值。

公开(公告)号：US06219144B1

公开(公告)日：2001-04-17

申请号：US09252440

申请日：1999-02-18

Applicant: Henry Allen Hill ,  Peter de Groot ,  Frank C. Demarest

Inventor： Henry Allen Hill ,  Peter de Groot ,  Frank C. Demarest

IPC: G01B902

CPC classification number: G01B9/02007 ,  G01B9/02003 ,  G01B9/02018 ,  G01B2290/70 ,  G01N21/45

Abstract: Apparatus and methods particularly suitable for use in electro-optical metrology and other applications to measure and monitor the refractive index of a gas in at least one measurement path and/or the change in optical path length of the measurement path due to the gas while the refractive index of the gas may be fluctuating due to turbulence or the like and/or the physical length of the measuring path may be changing. More specifically, the invention employs multiple pass interferometry to provide measurements of dispersion of the refractive index, the dispersion being substantially proportional to the density of the gas, and/or measurements of dispersion of the optical path length, the dispersion of the optical path length being related to the dispersion of the refractive index and the physical length of the measurement path. The refractive index of the gas and/or the optical path length effects of the gas are subsequently computed from the measured dispersion of the refractive index and/or the measured dispersion of the optical path length, respectively. The information generated by the inventive apparatus is particularly suitable for use in interferometric distance measuring instruments (DMI) to compensate for errors related to refractive index of gas in a measurement path brought about by environmental effects and turbulence induced by rapid stage slew rates. In preferred embodiments, differential plane mirror interferometer architectures are utilized, the operating wavelengths are approximately harmonically related and may be monitored and/or controlled to meet precision requirements, heterodyne and superheterodyne processing are beneficially used, and phase redundancy is resolved.

Abstract translation: 特别适用于电光计量学和其它应用的装置和方法，用于测量和监测至少一个测量路径中的气体的折射率和/或由于气体导致的测量路径的光程长度的变化，同时 气体的折射率可能由于湍流等而波动，和/或测量路径的物理长度可能改变。 更具体地说，本发明采用多通道干涉测量来提供折射率的色散的测量，该色散基本上与气体的密度成比例，和/或光程长度的色散的测量，光路长度的色散 与折射率的偏差和测量路径的物理长度有关。 随后根据测量的折射率的色散和/或光程长度的测量的色散分别计算气体的折射率和/或光程长度效应。 由本发明装置产生的信息特别适用于干涉测距仪（DMI），以补偿由环境影响引起的测量路径中的气体的折射率和由快速平台压摆率引起的湍流相关的误差。 在优选实施例中，使用差分平面镜干涉仪结构，工作波长几乎是谐波相关的，并且可以被监视和/或控制以满足精密要求，有利地使用外差和超外差处理，并且解决相位冗余。

公开(公告)号：US20080304077A1

公开(公告)日：2008-12-11

申请号：US11760535

申请日：2007-06-08

Applicant: Frank C. Demarest

Inventor： Frank C. Demarest

IPC: G01B9/02

CPC classification number: G01B9/02059 ,  G01B9/02003 ,  G01B9/02045 ,  G01B9/02084

Abstract: A first portion of a beam including a first frequency component is directed along a first path. A second portion of the beam is frequency shifted to generate a shifted beam that includes a second frequency component different from the first frequency component and one or more spurious frequency components different from the first frequency component. At least a portion of the shifted beam is directed along a second path different from the first path. An interference signal S(t) from interference between the beam portions directed along the different paths is measured. The signal S(t) is indicative of changes in an optical path difference n{tilde over (L)}(t) between the paths, where n is an average refractive index along the paths, {tilde over (L)}(t) is a total physical path difference between the paths, and t is time. An error signal is provided to reduce errors in an estimate of {tilde over (L)}(t) that are caused by at least one of the spurious frequency components of the shifted beam, the error signal being derived at least in part based on the signal S(t).

Abstract translation: 包括第一频率分量的波束的第一部分沿着第一路径被引导。 波束的第二部分被频移以产生包括不同于第一频率分量的第二频率分量和与第一频率分量不同的一个或多个寄生频率分量的移位波束。 移位光束的至少一部分沿着不同于第一路径的第二路径被引导。 测量沿着不同路径引导的光束部分之间的干涉的干涉信号S（t）。 信号S（t）表示路径之间的光程差n（波形）（L）}（t）的变化，其中n是沿着路径的平均折射率，（波形）（t）（t） ）是路径之间的总物理路径差，t是时间。 提供误差信号以减少由偏移波束的至少一个寄生频率分量引起的波形（L）}（t）估计中的误差，该误差信号至少部分地基于 信号S（t）。

公开(公告)号：US06525825B2

公开(公告)日：2003-02-25

申请号：US10095717

申请日：2002-03-12

Applicant: Peter de Groot ,  Henry A. Hill ,  Frank C. Demarest

Inventor： Peter de Groot ,  Henry A. Hill ,  Frank C. Demarest

IPC: G01B902

CPC classification number: G01B9/02007 ,  G01B9/02002 ,  G01B9/02027 ,  G01B9/02083 ,  G01B2290/60 ,  G01B2290/70

Abstract: Apparatus and methods particularly suitable for use in electro-optical metrology and other applications to measure and monitor the refractive index of a gas in a measurement path and/or the change in optical path length of the measurement path due to the gas while the refractive index of the gas may be fluctuating due to turbulence or the like and/or the physical length of the measuring path may be changing. Apparatus and method for measuring effects of the refractive index of a gas in a measurement path wherein the phase redundancy is resolved for phase signals.

Abstract translation: 特别适用于电光计量学和其他应用的测量和监测测量路径中的气体的折射率和/或由于气体导致的测量路径的光路长度的变化的设备和方法，而折射率 的气体可能由于湍流等而波动，和/或测量路径的物理长度可能会改变。 用于测量测量路径中气体的折射率的影响的装置和方法，其中对于相位信号解析相位冗余。

公开(公告)号：US07576868B2

公开(公告)日：2009-08-18

申请号：US11760535

申请日：2007-06-08

Applicant: Frank C. Demarest

Inventor： Frank C. Demarest

IPC: G01B11/02

CPC classification number: G01B9/02059 ,  G01B9/02003 ,  G01B9/02045 ,  G01B9/02084

Abstract: A first portion of a beam including a first frequency component is directed along a first path. A second portion of the beam is frequency shifted to generate a shifted beam that includes a second frequency component different from the first frequency component and one or more spurious frequency components different from the first frequency component. At least a portion of the shifted beam is directed along a second path different from the first path. An interference signal S(t) from interference between the beam portions directed along the different paths is measured. The signal S(t) is indicative of changes in an optical path difference n{tilde over (L)}(t) between the paths, where n is an average refractive index along the paths, {tilde over (L)}(t) is a total physical path difference between the paths, and t is time. An error signal is provided to reduce errors in an estimate of {tilde over (L)}(t) that are caused by at least one of the spurious frequency components of the shifted beam, the error signal being derived at least in part based on the signal S(t).

Abstract translation: 包括第一频率分量的波束的第一部分沿着第一路径被引导。 波束的第二部分被频移以产生包括不同于第一频率分量的第二频率分量和与第一频率分量不同的一个或多个寄生频率分量的移位波束。 移位光束的至少一部分沿着不同于第一路径的第二路径被引导。 测量沿着不同路径引导的光束部分之间的干涉的干涉信号S（t）。 信号S（t）表示路径之间的光程差n（波形）（L）}（t）的变化，其中n是沿着路径的平均折射率，（波形）（t）（t） ）是路径之间的总物理路径差，t是时间。 提供误差信号以减少由偏移波束的至少一个寄生频率分量引起的波形（L）}（t）估计中的误差，该误差信号至少部分地基于 信号S（t）。

公开(公告)号：US07428685B2

公开(公告)日：2008-09-23

申请号：US11060173

申请日：2005-02-17

Applicant: Frank C. Demarest ,  Henry A. Hill

Inventor： Frank C. Demarest ,  Henry A. Hill

IPC: G06F11/00

CPC classification number: G03F7/70775 ,  G01B9/02007 ,  G01B9/02059 ,  G01B9/0207 ,  G01B9/02084

Abstract: The invention features a method including: (i) providing an interference signal S(t) from two beams directed along different paths, wherein the signal S(t) is indicative of changes in an optical path difference n{tilde over (L)}(t) between the different paths, where n is an average refractive index along the different paths, {tilde over (L)}(t) is a total physical path difference between the different paths, and t is time; (ii) providing one or more coefficients representative of one or more errors that cause the signal S(t) to deviate from an ideal expression of the form A1 cos(ωRt+φ(t)+ζ1), where A1 and ζ1 are constants, ωR is an angular frequency difference between the two beams before being directed along the different paths, and φ(t)=nk{tilde over (L)}(t), with k=2π/λ and λ equal to a wavelength for the beams; (iii) calculating a linear combination of values of the signal S(t); and (iv) reducing the effect of the deviation of S(t) from the ideal expression on an estimate of {tilde over (L)}(t) using an error signal generated from the coefficients and one or more error basis functions derived at least in part from the linear combination of values of the signal S(t).

Abstract translation: 本发明的特征在于一种方法，包括：（i）从沿着不同路径引导的两个波束提供干扰信号S（t），其中信号S（t）表示不同路径之间的光程差nL（t）的变化 ，其中n是沿着不同路径的平均折射率，L（t）是不同路径之间的总物理路径差，t是时间; （ii）提供代表一个或多个错误的一个或多个系数，所述一个或多个错误导致信号S（t）偏离形式A＆lt; 1＆gt; > t + phi（t）+ zeta 1 ），其中A 1和Z 2是常数，ω' 是在沿着不同路径引导之前的两个波束之间的角频率差，并且phi（t）= nkL（t），其中k = 2pi /λ和λ等于波束的波长; （iii）计算信号S（t）的值的线性组合; 以及（iv）使用从系数产生的误差信号和至少部分地从线性方法导出的一个或多个误差基函数来减小S（t）与理想表达式的偏差对L（t）的估计的影响 信号S（t）的值的组合。

公开(公告)号：US06529279B2

公开(公告)日：2003-03-04

申请号：US10092107

申请日：2002-03-05

Applicant: Peter de Groot ,  Henry A. Hill ,  Frank C. Demarest

Inventor： Peter de Groot ,  Henry A. Hill ,  Frank C. Demarest

IPC: G01B902

CPC classification number: G01B9/02007 ,  G01B9/02002 ,  G01B9/02027 ,  G01B9/02083 ,  G01B2290/60 ,  G01B2290/70

Abstract: Apparatus and methods particularly suitable for use in electro-optical metrology and other applications to measure and monitor the refractive index of a gas in a measurement path and/or the change in optical path length of the measurement path due to the gas while the refractive index of the gas may be fluctuating due to turbulence or the like and/or the physical length of the measuring path may be changing. More specifically, the invention employs electronic frequency processing to provide measurements of dispersion of the refractive index, the dispersion being substantially proportional to the density of the gas, and/or measurements of dispersion of the optical path length, the dispersion of the optical path length being related to the dispersion of the refractive index and the physical length of the measurement path. The refractive index of the gas and/or the optical path length effects of the gas are subsequently computed from the measured dispersion of the refractive index and/or the measured dispersion of the optical path length, respectively. The information generated by the inventive apparatus is particularly suitable for use in interferometric distance measuring instruments (DMI) to compensate for errors related to refractive index of gas in a measurement path brought about by environmental effects and turbulence induced by rapid stage slew rates. In preferred embodiments, differential plane mirror interferometer architectures are utilized, the operating wavelengths are approximately harmonically related and may be monitored and/or controlled to meet precision requirements, heterodyne and superheterodyne processing are beneficially used, and phase redundancy is resolved.