Exact measurement of flat surface profiles by object shifts in a phase-conjugate Fizeau interferometer

1995 ◽  
Vol 34 (10) ◽  
pp. 2957 ◽  
Author(s):  
Osami Sasaki
Keyword(s):  
Flat Surface ◽  
Fizeau Interferometer ◽  
Phase Conjugate ◽  
Exact Measurement ◽  
Surface Profiles

Sinusoidal phase-modulating Fizeau interferometer using phase-conjugate wave

1993 ◽  
Author(s):  
Osami Sasaki ◽  
Xiangzhao Wang ◽  
Yuuichi Takebayashi ◽  
Takamasa Suzuki
Keyword(s):  
Fizeau Interferometer ◽  
Phase Conjugate ◽  
Sinusoidal Phase Modulating

scholarly journals Algorithm for Surfaces Profiles and Thickness Variation Measurement of a Transparent Plate Using a Fizeau Interferometer with Wavelength Tuning

2019 ◽  
Vol 9 (11) ◽  
pp. 2349 ◽  
Author(s):  
Tao Sun ◽  
Weiwei Zheng ◽  
Yingjie Yu ◽  
Ketao Yan ◽  
Anand Asundi ◽  
...  
Keyword(s):  
Rear Surface ◽  
Surface Profile ◽  
Measuring Method ◽  
Processing Technique ◽  
Repeated Measurements ◽  
Thickness Variation ◽  
Fizeau Interferometer ◽  
Transparent Plate ◽  
Surface Profiles ◽  
Step Algorithm

An interferogram obtained from a transparent plate contains information on the profiles of both surfaces and on the thickness variation. The present work is devoted to the processing of interferograms of this type. The processing technique is based on a 36-step algorithm developed by the authors for characterization of transparent plates having approximately equal reflections from both sides. The algorithm utilizes weighted multi-step phase shifting that enables one not only separately to extract the front and rear surface profiles together with the thickness variation of the tested plate but also to suppress the coupling errors between the higher harmonics and phase-shift deviation. The proposed measuring method was studied on a wavelength tunable Fizeau interferometer. The tested sample had an optical thickness and surface profile deviations equal to 0.51 µm, 1.38 µm and 0.89 µm, respectively. According to the results obtained using 10 repeated measurements, the root mean square (RMS) errors for determining both surface profiles did not exceed 1.5 nm. Experimental results show that the setup and presented 36-step algorithm are suitable for the measurement of a transparent plate of arbitrary thickness.

Phase-conjugate Fizeau interferometer

1989 ◽  
Vol 14 (6) ◽  
pp. 323 ◽  
Author(s):  
Daniel J. Gauthier ◽  
Robert K. Jungquist ◽  
Jerold B. Lisson ◽  
Robert W. Boyd ◽  
Laurie Lyon Voci
Keyword(s):  
Fizeau Interferometer ◽  
Phase Conjugate

Comparisons of Tribological Properties of Ti(C,N)/SiC in Water and Seawater

2015 ◽  
Vol 137 (2) ◽  
Author(s):  
Wei Huang ◽  
Haiye Liu ◽  
Xiaolei Wang
Keyword(s):  
Wear Resistance ◽  
High Temperature ◽  
Friction Coefficient ◽  
Flat Surface ◽  
High Temperature Strength ◽  
Low Friction ◽  
Sliding Speed ◽  
Silica Colloid ◽  
Salt Ions ◽  
Surface Profiles

Ti(C,N)-based cermets offer good high temperature strength, perfect chemical stability, excellent wear resistance, and relatively better machinability. In the present work, the tribological behaviors of Ti(C,N)/SiC sliding pairs lubricated in water and seawater were evaluated using a ball-on-disk tribometer. The experimental results show that a relatively low friction coefficient (about 0.025) can be obtained when lubricated with artificial seawater at the sliding speed of 200 mm/s, while the friction coefficient is about 0.2 in purified water. The wear surface profiles and the lubricants collected after running-in process for the high and low friction conditions were compared. In addition, the effects of salt molar concentration of the lubricant on the Ti(C,N)/SiC friction properties were investigated. It was found that the smooth and flat surface is the premise to gain the low friction. At the same time, the proper concentration of silica colloid, which is affected by the salt ions, is also an essential one. Moreover, the high sliding speed (200 mm/s) is beneficial to achieve low friction.

Polishing process effect on the image of dispersed precipitates

1984 ◽  
Vol 42 ◽  
pp. 534-535
Author(s):  
C.T. Hu ◽  
C.W. Allen
Keyword(s):  
Matrix Material ◽  
Specimen Preparation ◽  
Second Phase ◽  
Precipitate Particle ◽  
Polishing Process ◽  
Second Phase Particles ◽  
The Matrix ◽  
Surface Profiles ◽  
Thinning Process

One important problem in determination of precipitate particle size is the effect of preferential thinning during TEM specimen preparation. Figure 1a schematically represents the original polydispersed Ni3Al precipitates in the Ni rich matrix. The three possible type surface profiles of TEM specimens, which result after electrolytic thinning process are illustrated in Figure 1b. c. & d. These various surface profiles could be produced by using different polishing electrolytes and conditions (i.e. temperature and electric current). The matrix-preferential-etching process causes the matrix material to be attacked much more rapidly than the second phase particles. Figure 1b indicated the result. The nonpreferential and precipitate-preferential-etching results are shown in Figures 1c and 1d respectively.

Scanned tip measurement of deep vertical facets on a flat surface: Measuring roughness on gaas laser waveguide mirrors

1993 ◽  
Vol 51 ◽  
pp. 532-533
Author(s):  
Chang Shen ◽  
Phil Fraundorf ◽  
Robert W. Harrick
Keyword(s):  
Integrated Circuits ◽  
Flat Surface ◽  
Scanning Force Microscopy ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Force Microscopy ◽  
Optoelectronic Integrated Circuits ◽  
Laser Waveguide ◽  
Scanning Force ◽  
Gaas Laser

Monolithic integration of optoelectronic integrated circuits (OEIC) requires high quantity etched laser facets which prevent the developing of more-highly-integrated OEIC's. The causes of facet roughness are not well understood, and improvement of facet quality is hampered by the difficulty in measuring the surface roughness. There are several approaches to examining facet roughness qualitatively, such as scanning force microscopy (SFM), scanning tunneling microscopy (STM) and scanning electron microscopy (SEM). The challenge here is to allow more straightforward monitoring of deep vertical etched facets, without the need to cleave out test samples. In this presentation, we show air based STM and SFM images of vertical dry-etched laser facets, and discuss the image acquisition and roughness measurement processes. Our technique does not require precision cleaving. We use a traditional tip instead of the T shape tip used elsewhere to preventing “shower curtain” profiling of the sidewall. We tilt the sample about 30 to 50 degrees to avoid the curtain effect.

Calculation of many-beam dynamic electron diffraction without high-energy approximation

1996 ◽  
Vol 54 ◽  
pp. 128-129
Author(s):  
B. R. Ahn ◽  
N. J. Kim
Keyword(s):  
Electron Diffraction ◽  
Flat Surface ◽  
Dynamic Theory ◽  
High Energy ◽  
Perfect Crystal ◽  
Zone Axis ◽  
Beam Dynamic ◽  
Diffraction Angle ◽  
Energy Approximation ◽  
The Many

High energy approximation in dynamic theory of electron diffraction involves some intrinsic problems. First, the loss of theoretical strictness makes it difficult to comprehend the phenomena of electron diffraction. Secondly, it is difficult to believe that the approximation is reasonable especially in the following cases: 1) when accelerating voltage is not sufficiently high, 2) when the specimen is thick, 3) when the angle between the surface normal of the specimen and zone axis is large, and 4) when diffracted beam with large diffraction angle is included in the calculation. However, until now the method to calculate the many beam dynamic electron diffraction without the high energy approximation has not been proposed. For this reason, the authors propose a method to eliminate the high energy approximation in the calculation of many beam dynamic electron diffraction. In this method, a perfect crystal with flat surface was assumed. The method was applied to the calculation of [111] zone axis CBED patterns of Si.

PHASE CONJUGATE OSCI LLATORS

1983 ◽  
Vol 44 (C2) ◽  
pp. C2-43-C2-43
Author(s):  
A. Siegman
Keyword(s):  
Phase Conjugate

Evaluation of left atrial size and function – from M-mode to 3D speckle-tracking echocardiography

2014 ◽  
Vol 155 (41) ◽  
pp. 1624-1631 ◽  
Author(s):  
Attila Nemes ◽  
Tamás Forster
Keyword(s):  
Left Atrium ◽  
Left Atrial ◽  
Functional Characterization ◽  
Left Atrial Size ◽  
Dynamic Motion ◽  
Heart Chamber ◽  
Atrial Size ◽  
Exact Measurement ◽  
Heart Cycle ◽  
And Function

Left atrium is not a passive heart chamber, because it has a dynamic motion respecting heart cycle and, in accordance with its stretching, it releases atrial natriuretic peptides. Since in the course of certain invasive procedures the size of left atrium may change substantially, its exact measurement and functional characterization are essential. The aim of the present review is to summarize echocardiographic methods for the assessment of left atrial size and functional parameters. Orv. Hetil., 2014. 155(41), 1624–1631.

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