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View article: Dynamic Interferometry With Retrace Error Correction Using Fringe Projection For High-Gradient Fields
Dynamic Interferometry With Retrace Error Correction Using Fringe Projection For High-Gradient Fields Open
This paper introduces an innovative approach aimed at advancing the characterization of high-gradient flow fields through the integration of dynamic interferometry and fringe projection techniques. Traditional interferometry offers a preci…
View article: Two-wavelength interferometry for measurement of transonic airflow in a compressor blade cascade
Two-wavelength interferometry for measurement of transonic airflow in a compressor blade cascade Open
This paper presents high-speed two wavelength interferometry for measuring fast phenomena, which allows to extend the dynamic range of measurement using two different wavelengths at the same time. The method was applied to measure transoni…
View article: Aspheric surface measurement by absolute wavelength scanning interferometry with model-based retrace error correction
Aspheric surface measurement by absolute wavelength scanning interferometry with model-based retrace error correction Open
This paper presents a non-nulling absolute interferometric method for fast and full-area measurement of aspheric surfaces without the necessity of any mechanical movement. Several single frequency laser diodes with some degree of laser tun…
View article: Absolute wavelength scanning interferometry for measuring the thickness of optical elements
Absolute wavelength scanning interferometry for measuring the thickness of optical elements Open
A technique for measurement of the thickness of optical elements using absolute wavelength scanning interferometry is presented in this paper. To achieve high-grade optical components and systems, the thickness of both planar and non-plana…
View article: Quantitative Schlieren imaging based on fringe projection
Quantitative Schlieren imaging based on fringe projection Open
An effective yet simple quantitative synthetic Schlieren imaging technique is presented in this paper. A multiplexed fringe pattern displayed on a common laptop screen is observed through a disturbed medium resulting in a change of the fri…
View article: Characterization of Supersonic Compressible Fluid Flow Using High-Speed Interferometry
Characterization of Supersonic Compressible Fluid Flow Using High-Speed Interferometry Open
This paper presents a very effective interference technique for the sensing and researching of compressible fluid flow in a wind tunnel facility. The developed technique is very sensitive and accurate, yet easy to use under conditions typi…
View article: Digital Holographic Interferometry for the Measurement of Symmetrical Temperature Fields in Liquids
Digital Holographic Interferometry for the Measurement of Symmetrical Temperature Fields in Liquids Open
In this paper, we present a method of quantitatively measuring in real-time the dynamic temperature field change and visualization of volumetric temperature fields generated by a 2D axial-symmetric heated fluid from a pulsatile jet in a wa…
View article: Absolute interferometry for fast and precise radius measurement
Absolute interferometry for fast and precise radius measurement Open
A novel radius of the curvature measurement method for optical spherical surfaces using absolute interferometry is proposed. A measurement setup is designed and built around a common-path Fizeau interferometer. The cavity length (volume of…
View article: Traceable Reference Full Metrology Chain for Innovative Aspheric and Freeform Optical Surfaces Accurate at the Nanometer Level
Traceable Reference Full Metrology Chain for Innovative Aspheric and Freeform Optical Surfaces Accurate at the Nanometer Level Open
The design of innovative reference aspheric and freeform optical elements was investigated with the aim of calibration and verification of ultra-high accurate measurement systems. The verification is dedicated to form error analysis of asp…
View article: LA1256.ZIP
LA1256.ZIP Open
Sub-apertures measured on the LA1256 using TOPTEC AWA.
View article: Second Surface.zip
Second Surface.zip Open
Sub-apertures measured on the second experimetal surface using QED ASI.
View article: First Surface.zip
First Surface.zip Open
Sub-apertures measured on the first experimetal surface using QED ASI.
View article: Multiple angle digital holography for the shape measurement of the unpainted tympanic membrane
Multiple angle digital holography for the shape measurement of the unpainted tympanic membrane Open
The shape of the tympanic membrane (TM) plays an important role in sound transmission through the ear for hearing. Previously we developed a high-speed holographic system employing a tunable wavelength laser for rapid TM shape measurement.…
View article: Round robin comparison study on the form measurement of optical freeform surfaces
Round robin comparison study on the form measurement of optical freeform surfaces Open
A round robin comparison of freeform form measurements was carried out by the project partners and stakeholders of a European metrology research project. Altogether six measuring instruments were considered: five different (pointwise and a…
View article: Influence of mounting on the optical surface figure in optical reference surfaces
Influence of mounting on the optical surface figure in optical reference surfaces Open
The paper presents the effect of mechanical mounting of optical reference elements on their surface shape. Optical reference surfaces are key elements when traceable, highly accurate and precise optical surface measurements are required. I…
View article: Material standards design for minimum zone fitting of freeform optics
Material standards design for minimum zone fitting of freeform optics Open
In most cases, ultra-high-precision coordinate measuring machines (CMMs) are used to measure manufactured parts especially in the presence of freeform surfaces. The obtained data should be then processed to determine a quality measure of t…
View article: Alignment of solid targets under extreme tight focus conditions generated by an ellipsoidal plasma mirror
Alignment of solid targets under extreme tight focus conditions generated by an ellipsoidal plasma mirror Open
The design of ellipsoidal plasma mirrors (EPMs) for the PEARL laser facility is presented. The EPMs achieve a magnification of 0.32 in focal spot size, and the corresponding increase in focused intensity is expected to be about 8. Designin…
View article: Pixel-wise Amplitude Distribution Evaluation in Time Average Digital Holography
Pixel-wise Amplitude Distribution Evaluation in Time Average Digital Holography Open
This article introduces a new holographic method for harmonic vibration measurement. The method called time average sweeping digital holography (TASDH) is based on the continuous shift of fringe pattern described by Bessel function over th…
View article: Time average scanning digital holography
Time average scanning digital holography Open
Tento článek představuje novou metodu pro měření amplitud harmonických oscilací nazvanou časově středovaná skenovací digitální holografie. Rekonstruovaný intenzitní obraz z časově středovaného digitálního hologramu vytváří interferenční st…
View article: Dynamic interferometric measurement with extended unambiguity range in flow measurement
Dynamic interferometric measurement with extended unambiguity range in flow measurement Open
This paper reports on a new approach to measure dynamic processes in fluid mechanics using interferometry with extended dynamic range. A key factor is the use of two wavelengths and the recording of interferograms from both wavelengths in …
View article: Dynamic interferometric measurement with extended unambiguity range in flow measurement
Dynamic interferometric measurement with extended unambiguity range in flow measurement Open
This paper reports on a new approach to measure dynamic processes in fluid mechanics using interferometry with extended dynamic range. A key factor is the use of two wavelengths and the recording of interferograms from both wavelengths in …
View article: Validation of digital holographic tomography in flow measurement
Validation of digital holographic tomography in flow measurement Open
\nThis paper reports on measurements by digital holographic tomography in flow measurement. It is demonstrated capability of the method by measurement of general temperature field consisting of system of three orifices. Results obtained by…
View article: Limits Of Phase Modulated Frequency Shifted Holographic Vibrometry At Low Amplitudes Of Vibrations
Limits Of Phase Modulated Frequency Shifted Holographic Vibrometry At Low Amplitudes Of Vibrations Open
This paper presents advanced time average digital holography by means of frequency shift and phase modulation. This technique can measure amplitudes of vibrations at ultimate dynamic range while the amplitude distribution evaluation is don…