Optical coherence tomography (OCT) is a promising tool for detecting micro channels, metal prints, defects and delaminations embedded in alumina zirconia ceramic layers at hundreds of micrometers beneath surfaces. The effect surface roughness scattering probing radiation within sample on OCT inspection analyzed from the experimental simulated images samples with varying roughnesses operating wavelengths. By Monte Carlo simulations mid-IR optimal wavelength found to be 4 µm 2 achieving...

Although coherence scanning interferometry (CSI) is capable of measuring surface topography with sub-nanometre precision, it well known that the performance instruments depends strongly on local tilt and curvature sample surface. Based 3D linear systems theory, however, a recent analysis fringe generation in CSI provides method to characterize offers considerable insight into origins these errors. Furthermore, from measurement precision sphere, process calibrate partially correct has been...

Surface topography measurement for metal additive manufacturing (AM) is a challenging task contact and noncontact methods. We present an experimental investigation of the use coherence scanning interferometry (CSI) measuring AM surfaces. Our approach takes advantage recent technical enhancements in CSI, including high dynamic range light level adjustable data acquisition rates noise reduction. The covers several typical surfaces made from different materials processes. Recommendations...

Optical technology in the mid-infrared wavelength range is currently a rapidly developing field initiated by availability of novel high-power and spatially coherent sources.Non-destructive testing techniques based on these sources are very promising for industrial medical applications.However, there still many engineering problems due to technical challenges high prices optical elements suitable region.In this paper, we report development performances first Fourier-domain coherence...

Emergence of products that feature functional surfaces with complex geometries, such as freeform optics in consumer electronics and augmented reality virtual reality, requires high-accuracy non-contact surface measurement. However, large discrepancies are often observed between the measurement results optical methods contact stylus methods, especially for surfaces. For interference microscopy, coherence scanning interferometry, three-dimensional transfer function provides information about...

Abstract Coherence scanning interferometry is one of the most accurate surface measuring technologies, and it increasingly applied to challenging structures, such as additive manufactured parts transparent films, directly in environments that resemble production areas more than metrology labs. Environmental disturbances may further compromise measurement accuracy. Data acquisition strategies reduce noise coherence include averaging a sequence repeated topography measurements or increasing...

This paper presents an on-machine surface defect detection system using light scattering and deep learning. A supervised learning model is used to mine the information related defects from patterns. convolutional neural network trained on a large dataset of patterns that are predicted by rigorous forward model. The valid for any topography with homogeneous materials has been verified comparing experimental data. Once trained, it allows fast, accurate, robust detection. capability validated...

Surface topography measuring interference microscopy is a three-dimensional (3D) imaging technique that provides quantitative analysis of industrial and biomedical specimens. Many different instrument modalities configurations exist, but they all share the same theoretical foundation. In this paper, we discuss unified framework for 3D image (interferogram) formation in microscopy. We show how scattered amplitude linearly related to surface according Born Kirchhoff approximations highlight...

Virtual instruments provide task-specific uncertainty evaluation in surface and dimensional metrology. We demonstrate the first virtual coherence scanning interferometer that can accurately predict results from measurements of surfaces with complex topography using a specific real instrument. The instrument is powered by physical models derived principles, including surface-scattering models, three-dimensional imaging theory, error-generation models. By incorporating influences various error...

Two major fields of study in optics—holography and interferometry—have developed at times independently other together. The two methods share the principle holistically recording as an intensity pattern magnitude phase distribution a light wave, but they can differ significantly how these recordings are formed interpreted. Here we review seven specific developments, ranging from data acquisition to fundamental imaging theory three dimensions, that illustrate synergistic developments...

Coherence scanning interferometry (CSI), a type of interference microscopy, has found broad applications in the advanced manufacturing industry, providing high-accuracy surface topography measurement. Enhancement metrological capability CSI for complex surfaces, such as those featuring high slopes and spatial frequencies aspect-ratio structures, requires advances modeling CSI. However, current linear models relying on approximate scattering cannot accurately predict instrument response...

Orientation affects application-defining properties of crystalline materials. Hence, information in this regard is highly-prized. We show that electrochemical jet processing (EJP), when coupled with accurate metrological appraisal, can characterise crystallographic texture. Implementation technique allows localised dissolution to be anisotropic and dependent on etch-rate selectivity, defined by the crystallography. EJP therefore, generates complex, but characteristic topographies. Through...

Abstract Point autofocus instruments are often used for measuring the surface topography of objects with complex geometry. Determining metrological characteristics instrument is key to ensuring a traceable areal measurement. In this work, several characteristics, as outlined in ISO/FDIS 25178-600, determined commercial point instrument, including flatness deviation, amplification and linearity lateral vertical axes, perpendicularity between axes. Calibrated material measures an optical flat,...

Manufacturers nowadays have access to state-of-the-art areal surface topography measurement instruments that allow investigation of at unprecedented levels detail and over a wide range scales. However, high value-added products demanding requirements, pushing technologies their limits. Therefore, deeper insight more comprehensive understanding performance behaviour current solutions is often needed. In this work, we investigate compare the results when measuring same with different,...

Lateral optical distortion is present in most imaging systems. In coherence scanning interferometry, may cause field-dependent systematic errors the measurement of surface topography. These become critical when high-precision surfaces, e.g. precision optics, are measured. Current calibration and correction methods for require some form artefact that has a smooth local grid manufactured features. Moreover, to ensure high accuracy absolute relative locations features these artefacts, requires...

Coherence scanning interferometry (CSI) offers threedimensional (3D) measurement of surface topography with high precision and accuracy.Defocus within the interferometric objective lens, however, is commonly present in CSI measurements reduces both resolving power imaging system ability to measure tilted surfaces.This Letter extends linear theory consider effects defocus on 3D transfer function point spread an otherwise ideal instrument.The results are compared these functions a real...

Customers pay significant attention to the organoleptic and physicochemical attributes of their food with improvement living standards. In this work, near infrared hyperspectral technology was used evaluate one-color parameter, a*, firmness, soluble solid content (SSC) Korla fragrant pears. Moreover, iteratively retaining informative variables (IRIV) least square support vector machine (LS-SVM) were applied together construct evaluating models for quality parameters. A set 200 samples chosen...

The optical distortion of the lithographic projection lens can reduce imaging quality and cause overlay errors in lithography, thus preventing miniaturization printed patterns. In this paper, we propose a technique to measure by sensing wavefront aberrations lens. A multichannel dual-grating lateral shearing interferometer is used at several field points pupil plane simultaneously. Then, these derived according proportional relationship between

Coherence scanning interferometry (CSI) is a widely used optical method for surface topography measurement of industrial and biomedical surfaces. The operation CSI can be modeled using approximate physics-based approaches with minimal computational effort. A critical aspect modeling defining the transfer function imaging properties instrument to predict interference fringes from which information extracted. Approximate methods, example, elementary Fourier optics, universal foil models, use...

Large-scale and cost-effective manufacturing of ceramic micro devices based on tape stacking requires the development inspection systems to perform high-resolution in-process quality control embedded manufactured cavities, metal structures defects.With an optical coherence tomography (OCT) system operating at 1.3 µm a dedicated automated line segmentation algorithm, layer thicknesses can be measured laser-machined channels verified in alumina ceramics around 100 depth.Monte Carlo simulations...

Optical coherence tomography (OCT) is a high-resolution three-dimensional imaging technique that enables nondestructive measurements of surface and subsurface microstructures. Recent developments OCT operating in the mid-infrared (MIR) range (around 4 µm) lifted fundamental scattering limitations initiated applied material research formerly inaccessible fields. The MIR spectral region, however, also great interest for spectroscopy hyperspectral imaging, which allow highly selective sensitive...