Thickness Measurement System Research Articles

基于AVR单片机的高精度光学测厚系统设计

The thin film thickness system is analyzed in detail,and the film thickness measuring system is discussed on the whole.The key parts of hardware circuit is studied in film thickness instrument of thickness measuring system,and the software flow of the film thickness instrument is designed discretely.The AVR microcontroller as the core processor for data acquisition and processing,the on-line optical thin film thickness measurement and monitoring system is designed and manufactured.By contrast experiment with the actual film thickness,it is verified that the thin film measuring system has high precision,high stability and high reliability.It can be applied to practical industrial production.

On-Line Thickness Measurement of Thin Film Based on Neural Network

This paper proposes a on-line thickness measurement scheme of thin film based on the capacitance thickness sensor and introduces the composition and principle of thickness measurement system. Then it further states the principle and simulation of the RBF neural network, which can effectively predict the thickness deviation of thin film by setting the appropriate parameters. The monitoring method based on the RBF neural network will reduce production cost and make the film thickness uniformity better, combining the traditional film production line with an new idea of controlling the opening degree of wind ring.

Development of Thickness Measurement System for Hot Steel with Laser-Ultrasonic Wave Technology

Development of Thickness Measurement System for Hot Steel with Laser-Ultrasonic Wave Technology

Application of the Ultrasonic Oil Film Thickness Measurement System in Bearing Chambers

The oil film thickness in aero-engine bearing chamber influences the heat transfer capacity of the bearing chamber wall, so measuring oil film thickness accuspeedly is essential to the design and thermal analysis of lubricating oil system. In this paper, software and hardware of an ultrasonic measurement system based on pulse echo technique, which measures the oil film thickness in bearing chamber, are established. The hardware system mainly consists of signal acquisition card, probe, delay block and the corresponding cables. Functions as measurement parameter setup, real-time display of measured waveforms, post-processing and so on are included in the measurement software. Finally, the oil film thickness of the wall is measured with the measurement system developed. Signal quality of the dynamic measurement is analyzed. Comparison and analysis of different oil film thickness under different rotation rates are conducted.

Refractive Index and Effective Thickness Measurement System for the RGB Color Filter Coatings With Absorption and Scattering Properties

During the manufacturing processes of the thin-film transistor liquid-crystal display (TFT-LCD) panel, red, green, and blue (RGB) color filter coatings undergo the layer-adding process which causes the rough surfaces between the layers. The rough surfaces make acquiring an accurate measurement of the optical properties and thickness (n, k, d) much more difficult because the scattering effects occur. The effective layer-included model is considered in determining the (n, k, d) by including effective layers to reside between and above the multilayer (ML). To show the feasibility of the effective layer-included model, we examined the model by fitting the (n, k, d) for different virtual systems which contain different kinds of scatters reside between and above it. Our findings show that the fitted (n, k, d) can be closer to the assumed (n, k, d) by using the effective layer-included model rather than the standard model. Also, the tolerance of initial assigned (n, k, d) regions to obtain the accurate results are investigated. Further, both models are used to determine the (n, k, d) of the fabricated RGB color filter samples. In the experimental measurements, all reflection and transmission signals are measured by utilizing the in-house variable angle spectroscopic ellipsometry (VASE) system. Consequently, the thicknesses determined from effective layer-included model are closer to the thicknesses measured from profilometry (Alpha-step 100). Also, the transmissions under 0 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">°</sup> , 15 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">°</sup> , and 30 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">°</sup> illuminations calculated from the fitted (n, k, d) through the effective layer-included model are closer to the VASE measurements rather than the standard model for each sample. We conclude that the effective layer-included model can be used to determine the accurate (n, k, d) of RGB color filter coatings with rough surface.

Development of free curved plate thickness measurement system - Improvement of interpolation for continuous path -

Development of free curved plate thickness measurement system - Improvement of interpolation for continuous path -

Study of Electrical Thickness Measurement System Technology of Composite

Based on four-terminal network theory, a multilayered model for reflective electrical thickness measurement system is presented in this paper. Using the simulation method of finite element, two crucial parameters of the measurement system are given. One parameter is the distance between the inner surface of composite and reflective mold, the other is the outer surface of composite and horn antenna aperture. This work will guarantee the design of the electrical thickness measurement system of composite.

A Thin Silicon Wafer Thickness Measurement System by Optical Reflectmetry Scheme Using Fourier Transform Near-Infrared Spectrometer

In this study, measurable thickness range was improved by re-customized components of the thickness measurement system using the method of Fabry-Perot interference signature analyzing. A Fourier transform near infrared (FT-NIR) spectrometer with indium gallium arsenide was used in the developed system. As a result of the sensitiveness in the whole near infrared band and high spectral resolution united with high signal noise ratio of the FT-NIR spectrometer, the maximum measurable thickness is improved to 88μm while sub-micron order of the minimum measurable thickness is also improved.

Research on Optical Properties and Micro-processing Characteristics of Collodion Thin Film

Colorless and transparent thin films of collodion are prepared on silicon wafers and K9 optical glass substrates by using spin-coating technique. The visible light transmittance, IR absorption spectra and optical constants of collodion thin film are measured by UV-3501 Spectrophotometer, Fourier transform infrared spectrometer (FTIR) and spectroscopic ellipsometry. The measured results show that its average visible light transmittance is 91.9%, and its average infrared absorptivity is better than 0.69/um. In the visible light region, the refractive index of collodion thin film changes in the range of 1.5–1.53, which accords with normal dispersion. The collodion films are etched using oxygen gas plasma. The surface morphology and thickness of etched thin film are measured by the polarizing microscope and MP-100S thickness measurement system, respectively. The results show that the collodion thin film is etched out in the oxygen gas plasma.

Design the CCD Tablet Thickness Measurement System Based on Laser Triangulation Method

This system brings forward the CCD measurement method based on oblique laser triangulation , which to resolve the minimal thickness measurement precision problem, in this system use linear array CCD, then used CCD as a photoelectric conversion device, the image on the CCD image point displacement variation to realize planar sheet thickness measurement, design and construction of the contactless thickness measurement system. Finally, the experimental analyze the measurement error of the system, prove the feasibility and validity of the system.

Fiber-based optical coherence tomography for biomedical imaging, sensing, and precision measurements

Recently published studies on fiber-based optical coherence tomography (OCT) are reviewed mainly in relation to applications within the fields of biomedical imaging and precision measurement. A succinct introduction to fiber-based OCT system configurations is described including history, related core components, and functional characteristics. Then, an overview of fiber-optic probes is presented in terms of actuating method, scanning direction, and functionality. In order to verify the performance of fiber-optic OCT systems, fiber-based OCT images of several biological samples including pearls, fingers, teeth, and tumor tissues are presented. A multi-functional modality combined with laser induced fluorescence spectroscopy is also presented to distinguish between similar samples. Finally, some interesting fiber-optic OCT studies are briefly presented to measure various physical, chemical, and biological parameters. In particular, simultaneous refractive index and thickness measurement systems with self-referencing and dual probing techniques are introduced. Also, high precision measurement using a common-path OCT configuration is demonstrated with the help of Fourier domain phase analysis.

Research on Visualization of Cutting Tools' Wear Measurement of Shield

In this paper the principle and method of the ultrasonic thickness measurement are introduced, and a kind of thickness measurement system based on single chip microcomputer is set forth, which is used for shield cutters’ wear measurement. besides, the collected data is processed by way of MATLAB software which can display the intuition image of the present situation of the tool wear and provide the reliable guarantee for real-time detection of the cutting tool.

In-situ measurement of Cu film thickness during the CMP process by using eddy current method alone

An eddy current measurement system for Cu thickness in CMP was established.The nano-scale sensitivity under large lift-off distance was reached by optimizing.The differential method for signal processing avoids the drift of system. A fast, accurate and in situ method for determination of interconnect Cu film thickness in the range from 200 to 500nm is a crucial requirement in the stress free polishing (SFP) process which is a novel semiconductor manufacture technique. This paper presents an in situ Cu film thickness measurement system with an optimized eddy current transducer for this purpose. The fabricated transducer has been integrated into a chemical mechanical polishing (CMP) platform for the purpose of testing. Measurement tests for both the Cu film with uniform thickness and the Cu film with interconnects are conducted. The CMP experiment results show that the resolution of the transducer can achieve a few nanometers under 3mm lift-off distance. With the increase in the density of the underlying Cu interconnects, the measured thickness value of the overlaid Cu film is also increased. By using an on-line differential signal processing method, the drift of the measurement system is removed. The repeatability and instability errors are less than 1.6%. The system can meet the technical requirements for advanced CMP processes.

Corrosion Monitoring Strategies—Choice Between Area and Point Measurements

There is increasing interest in the use of permanently installed monitoring systems to track the progress of corrosion. There is a choice between point thickness measurement systems, those that monitor the average thickness over a modest area, and large area monitoring systems that will detect relatively severe, localised corrosion. The relative merits of the different types of monitoring system are assessed for cases with different likely fractions of the total surface area affected by corrosion. If the wall loss is expected to be fairly uniform over the component surface then a small number of point sensors is the most attractive solution, whereas if the loss is likely to be highly localised at an unpredictable location and potentially severe, a large area monitoring system is most suitable. In the intermediate case of modest loss over a significant fraction of the surface, the choice is more complex. If the requirement is to detect relatively large wall loss that may be localised then the number of point sensors required increases substantially and the average thickness area monitoring systems appear to be more attractive. However, it is shown that corrosion distributions are frequently exponential, and this can lead to large maximum pit depths when the average wall loss is at the margin of detectability with current commercially available systems.

Experimental and numerical investigations of oil film formation and friction in a piston ring–liner contact

The piston ring–cylinder liner contact is a major source of the total parasitic losses in an internal combustion engine. The lubrication process of this contact highly influences the amount of friction, oil consumption and wear that occurs. In this work, a reciprocating test rig combined with an ultrasonic film thickness measurement system was developed and then used for tribological investigation of the piston ring–cylinder liner contact under idealised cold conditions. A special piston ring and cylinder liner holder were designed and five sensors were glued on to the back side of the liner specimen. Ultrasonic reflections captured by the sensors, used to obtain the film thickness, and friction were continuously recorded as the piston ring section reciprocated over the liner. Several experiments were performed at different speed and load conditions. Furthermore, a numerical model has been developed to predict film thickness and friction in all lubrication regimes. The experimentally measured film thickness and friction were compared with the output from the numerical model and good correlation was found. The parameters affecting the accuracy of the ultrasound measurements and numerical simulations of film thickness and friction are then discussed.

Influence of Dynamic Properties and Position of Rivulet on Rain–Wind-Induced Vibration of Stay Cables

AbstractThis paper combines an experimental study and computational fluid dynamics (CFD) simulations to investigate the influence of dynamic properties and position of upper rivulet on rain–wind-induced vibration (RWIV) of stay cables. The reproduction of the RWIV of a stay cable model is first performed based on artificial rainfall wind tunnel tests with an ultrasonic transmission thickness measurement system, which can obtain the characteristics of rivulets on the surface of the stay cable model. On the basis of the test results, CFD simulations are then used to study the aerodynamic influence of an upper rivulet using two different CFD models: a vibrating cable model with a moving upper rivulet and a vibrating cable model with a fixed upper rivulet. CFD simulations suggest that the existence of the upper rivulet do not sufficiently to excite RWIV. It is confirmed that, when an upper rivulet oscillates in a specific range at the same frequency of a cable, it can significantly vary the aerodynamic force ...

３波長干渉を用いた透明膜の膜厚分布測定装置の開発 広域モデル適合（GMF）アルゴリズムの拡張

３波長干渉を用いた透明膜の膜厚分布測定装置の開発 広域モデル適合（GMF）アルゴリズムの拡張

Application of Automatic Ultrasonic Wall Thickness Measurement System in Nuclear Fuel Encrust Tube Billet Wall Abrasive Grinding

This paper introduces an automatic ultrasonic wall thickness measurement system, which adopts the way that the tube billet is partially immersed in the water during the measurement, applied in wall abrasive grinding of nuclear fuel encrust tube billet. Meanwhile, the main components of the measurement system, as well as their characters and functions, are addressed. What’s more, the analysis of the factors, which influencing the system stability and measuring reliability, are also conducted, coupling with the system stability and measuring reliability demonstration.

Testing of a CNC Control Abrasive Belt Grinding Machine Based on Ultrasonic Thick Measure for Nuclear Zirconium Alloy

A highly efficient precision grinding method was proposed for the development of Zr-4 alloy used in nuclear industry. The key techniques to develop this new grinding machine are presented in detail, including soft grinding wheel head, ultrasonic thickness measurement system. An automatic polishing and grinding system was built, which is based on ultrasonic thickness measurement technology. According to a lot of grinding experiments, reasonable, accurate and efficient Zr-4 Alloy grinding parameters was determined. The experiments show that when the line speed of belt is about 18 m/s; the workpiece feed rate is 1000mm/min; grinding head cylinder pressure is 0.12Mpa, the silicon carbide abrasive belt of P80 particle size can get 0.02mm grinding amount and achieve excellent grinding effect.

A Cable Sheath Material Thickness Measurement Method Based on Image Measurement Technology

Sub-pixel positioning is a key technology in geometry measurement field. Reckoning on the low accuracy of ordinary polynomial interpolation for sub-pixel positioning method because of losing the position of edge points, an improved Sobel edge detection method is first proposed, and then is applied to the thickness measurement system of cable sheath material. The experiment shoes that the edge coordinateonthe detected by our proposed interpolation method is more colse to the real edge than the original method.