公开(公告)号：US20120162657A1

公开(公告)日：2012-06-28

申请号：US13411600

申请日：2012-03-04

Applicant: Robert J. Rafac ,  Scot T. Smith

Inventor： Robert J. Rafac ,  Scot T. Smith

IPC: G01J3/45

CPC classification number: G01J3/02 ,  G01J1/4257 ,  G01J3/0205 ,  G01J3/027 ,  G01J3/0291 ,  G01J3/0297 ,  G01J3/1256 ,  G01J3/26 ,  G01J9/02 ,  G01J2009/0249 ,  G01J2009/0257 ,  G02B5/04 ,  G02B5/284 ,  G02B27/48 ,  G03F7/70025 ,  G03F7/70583 ,  H01S3/005

Abstract: A method includes directing a portion of a laser beam output from a laser along a secondary beam path toward a detector, the secondary beam path being distinct from a main beam path of the laser beam; generating a bandwidth selective interference pattern of the laser beam on the detector; detecting, at the detector, a width of a fringe within the interference pattern to thereby measure measuring a bandwidth of the laser beam; and homogenizing the laser beam traveling along the secondary beam path prior to generation of the bandwidth selective interference pattern. The homogenizing includes diffusing the laser beam; and introducing a time dependent, position dependent, or both time and position dependent random modulation to the wavefront of the laser beam to reduce fluctuations in the detected fringe width and to reduce the influence of spatial coherence of the laser beam on the detected interference pattern.

Abstract translation: 一种方法包括将从激光器输出的激光束的一部分沿着次级光束路径引向检测器，次级光束路径与激光束的主光束路径不同; 在检测器上产生激光束的带宽选择性干涉图案; 在检测器处检测干涉图案内的边缘的宽度，从而测量测量激光束的带宽; 并且在产生带宽选择干涉图案之前均匀化沿着次级光束路径行进的激光束。 均质化包括扩散激光束; 并且将与时间有关的位置依赖性或时间和位置相关随机调制引入到激光束的波前以减少检测到的条纹宽度的波动并减少激光束的空间相干性对检测到的干涉图案的影响。

公开(公告)号：US5231468A

公开(公告)日：1993-07-27

申请号：US788395

申请日：1991-11-06

Applicant: Vance A. Deason ,  Gordon D. Lassahn

Inventor： Vance A. Deason ,  Gordon D. Lassahn

IPC: G01B9/02 ,  G01J9/02

CPC classification number: G01J9/02 ,  G01B9/0207 ,  G01J2009/0226 ,  G01J2009/0249

Abstract: A method and apparatus resulting in the simplification of phase shifting interferometry by eliminating the requirement to know the phase shift between interferograms or to keep the phase shift between interferograms constant. The present invention provides a simple, inexpensive means to shutter each independent beam of the interferometer in order to facilitate the data acquisition requirements for optical interferometry and phase shifting interferometry. By eliminating the requirement to know the phase shift between interferograms or to keep the phase shift constant, a simple, economical means and apparatus for performing the technique of phase shifting interferometry is provide which, by thermally expanding a fiber optical cable changes the optical path distance of one incident beam relative to another.

Abstract translation: 一种方法和装置，通过消除干涉图之间的相移的要求或者使干涉图之间的相移保持不变，从而简化了相移干涉测量。 本发明提供了一种简单，便宜的方式来对每个干涉仪的独立光束进行快门，以便于光学干涉测量和相移干涉测量的数据采集需求。 通过消除干涉图之间的相位偏移或保持相位偏移的要求，提供了一种用于执行相移干涉测量技术的简单，经济的手段和装置，其通过光纤光缆的热膨胀改变光路距离 相对于另一个入射光束。

公开(公告)号：US20160282190A1

公开(公告)日：2016-09-29

申请号：US14927320

申请日：2015-10-29

Applicant: ARTUR OLSZAK

Inventor： ARTUR OLSZAK

IPC: G01J9/02 ,  H01S3/00

CPC classification number: G01J9/02 ,  G01B9/02004 ,  G01B9/02005 ,  G01J2009/0249 ,  G02F1/01 ,  G02F1/0121 ,  G02F2203/05

Abstract: A tunable light source having a temporal coherence length such that interference fringes are detected within the optical path difference of the interferometer is spectrally controlled to produce multiple wavelengths during sequential fractions of the integration time of the detector of the interferometer. The wavelengths are selected so as to produce a visible correlogram at each integration time according to spectrally controlled interferometry (SCI) principles. Such different wavelengths may be produced by stepwise or continuous modulation. The modulation step is repeated sequentially while changing the period of modulation to produce a succession of predetermined spatial patterns of interference fringes, as required for interferometric measurements. The approach enables the practice of SCI with common-path apparatus used for conventional phase shifting, thereby combining the advantages of high-coherence and white-light interferometry. A suitable time-modulated source combines a coherent source with an optical modulator and a waveform generator synchronized with the source.

Abstract translation: 具有时间相干长度的可调谐光源，使得在干涉仪的光程差内检测到干涉条纹被光谱控制，以在干涉仪的检测器的积分时间的连续分数期间产生多个波长。 选择波长以便根据光谱控制的干涉测量（SCI）原理在每个积分时间产生可见的相关图。 这种不同的波长可以通过逐步或连续的调制来产生。 顺序地重复调制步骤，同时根据干涉测量的要求改变调制周期以产生一系列预定的干涉条纹的空间图案。 该方法使得用于常规相移的通路设备的SCI的实践，从而结合了高相干性和白光干涉测量的优点。 合适的时间调制源将相干光源与光调制器和与源同步的波形发生器组合。

公开(公告)号：US20050286599A1

公开(公告)日：2005-12-29

申请号：US10881533

申请日：2004-06-29

Applicant: Robert Rafac ,  Scot Smith

Inventor： Robert Rafac ,  Scot Smith

IPC: G01J1/42 ,  G01J3/02 ,  G01J3/12 ,  G01J3/26 ,  G01J9/02 ,  G02B5/04 ,  G02B5/28 ,  G02B27/48 ,  G03F7/20 ,  H01S3/00 ,  H01S3/08 ,  H01S3/22

CPC classification number: G01J3/02 ,  G01J1/4257 ,  G01J3/0205 ,  G01J3/027 ,  G01J3/0291 ,  G01J3/0297 ,  G01J3/1256 ,  G01J3/26 ,  G01J9/02 ,  G01J2009/0249 ,  G01J2009/0257 ,  G02B5/04 ,  G02B5/284 ,  G02B27/48 ,  G03F7/70025 ,  G03F7/70583 ,  H01S3/005

Abstract: A method and apparatus for producing with a gas discharge laser an output laser beam comprising output laser light pulses, for delivery as a light source to a utilizing tool is disclosed which may comprise a beam path and a beam homogenizer in the beam path. The beam homogenizer may comprise at least one beam image inverter or spatial rotator, which may comprise a spatial coherency cell position shifter. The homogenizer may comprise a delay path which is longer than, but approximately the same delay as the temporal coherence length of the source beam. The homogenizer may comprise a pair of conjoined dove prisms having a partially reflective coating at the conjoined surfaces of each, a right triangle prism comprising a hypotenuse face facing the source beam and fully reflective adjoining side faces or an isosceles triangle prism having a face facing the source beam and fully reflective adjoining side faces or combinations of these, which may serve as a source beam multiple alternating inverted image creating mechanism. The beam path may be part of a bandwidth measuring the bandwidths of an output laser beam comprising output laser light in the range of below 500 femtometers at accuracies within tens of femtometers. The homogenizer may comprise a rotating diffuser which may be a ground glass diffuser which may also be etched. The wavemeter may also comprise a collimator in the beam path collimating the diffused light; a confocal etalon creating an output based upon the collimated light entering the confocal etalon; and a detector detecting the output of the confocal etalon and may also comprise a scanning mechanism scanning the angle of incidence of the collimated light entering the confocal etalon which may scan the collimated light across the confocal etalon or scan the etalon across the collimated light, and may comprise an acousto-optical scanner. The confocal etalon may have a free spectral range approximately equal to the E95 width of the beam being measured. The detector may comprise a photomultiplier detecting an intensity pattern of the output of the confocal etalon.

公开(公告)号：US5026977A

公开(公告)日：1991-06-25

申请号：US538896

申请日：1990-06-15

Applicant: James E. Hubbard, Jr.

Inventor： James E. Hubbard, Jr.

IPC: G01J9/02

CPC classification number: G01J9/02 ,  G01J2009/0249

Abstract: A closed loop system sends one portion of a coherent laser beam along a first path and another portion of the beam along a second path which is directed at a mirror formed on piezoelectric membrane. After reflection, both return beams are mixed on a photodetector array and the array output is analyzed to determine the values of a charge distribution on the piezoelectric membrane which will null or maintain constant the phase of the mixed beam.

Abstract translation: 闭环系统沿着沿着第二路径的第一路径和第二路径沿着第一路径发送一部分相干激光束，该第二路径指向形成在压电膜上的反射镜。 在反射之后，将两个返回光束混合在光电检测器阵列上，并且分析阵列输出以确定压电膜上的电荷分布的值，其将使混合光束的相位失真或保持恒定。

公开(公告)号：US4905169A

公开(公告)日：1990-02-27

申请号：US366348

申请日：1989-06-15

Applicant: Tudor N. Buican ,  John C. Martin

Inventor： Tudor N. Buican ,  John C. Martin

IPC: G01J3/447 ,  G01J3/453 ,  G01J9/02 ,  G01N15/10 ,  G01N15/14

CPC classification number: G01J3/453 ,  G01J3/447 ,  G01J9/0246 ,  G01J2009/0249 ,  G01J2009/0265 ,  G01N15/14 ,  G01N2015/1006 ,  G01N2021/6439

Abstract: An apparatus and method simultaneously measures a plurality of spectral wavelengths present in electromagnetic radiation. A modulatable birefringent optical element is employed to divide a polarized light beam into two components, thereby producing a phase difference in two resulting light beams such that the two beams can be made to interfere with one another when recombined, the interference pattern providing the wavelength information required for the analysis of the incident light. The interferometer thus created performs in a similar manner to a Michelson interferometer, but with no moving parts, and with a resolution dependent on the degree of phase shift introduced by the modulator.

Abstract translation: 一种装置和方法同时测量电磁辐射中存在的多个光谱波长。 采用可调制的双折射光学元件将偏振光束分成两个分量，从而在两个产生的光束中产生相位差，使得当重新组合时可以使两个光束彼此干扰，提供波长信息的干涉图案 需要分析入射光。 这样创建的干涉仪以与迈克尔逊干涉仪类似的方式执行，但没有移动部件，并且具有取决于由调制器引入的相移程度的分辨率。

公开(公告)号：US4743114A

公开(公告)日：1988-05-10

申请号：US884695

申请日：1986-07-11

Applicant: Robert Crane, Jr.

Inventor： Robert Crane, Jr.

IPC: G01J3/12 ,  G01J3/26 ,  G01J9/02 ,  G01S3/782 ,  G01J3/45

CPC classification number: G01J9/02 ,  G01S3/782 ,  G01J2003/1243 ,  G01J2009/0211 ,  G01J2009/0249 ,  G01J3/26 ,  G01J9/0246

Abstract: An imaging coherent radiometer incorporating a Fabry-Perot interferometer which is scanned or nutated, for detecting and determining location and wavelength of coherent radiation or the coherent absence of radiation in the presence of non-coherent ambient radiation.

Abstract translation: 包含被扫描或章程化的法布里 - 珀罗干涉仪的成像相干辐射计，用于在存在非相干环境辐射的情况下检测和确定相干辐射的位置和波长或相干不存在辐射。