Read PDF Holographic Interferometry: Principles and MethodsDigital holographic interferometry has been developed by ONERA for analysing high refractive index variations encountered in fluid mechanics. First, the authors present the analysis of a small supersonic jet using three different optical techniques based on digital Michelson holography, digital holography using Wollaston prisms and digital holography without reference wave. A comparison of the three methods is given. The time evolution of the gas density field around a circular cylinder is given at Mach 0. Finally, a digital holographic method is presented to visualize and measure the refractive index variations occurring inside a transparent and strongly refracting object.
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Robinson, the reference phase is subtracted from the phase object. For maps of phase difference, G. It can be seen that calcite birefringence is basically twenty times greater than quartz birefringence. The problem encountered with configuration no.Holographic interferometry. A very good agreement can be observed. Add a comment. In these conditions, the sensor can be adjusted along the optical axis to focus and image the middle of the test section on the sensor.
But, in fluid mechanics, the data obtained must be integrated. But moving up-and-down produces no change in spatial perspective and viewer only sees a change of colour. In addition, an amplitude image and a phase image can be calculated. After reconstruction of the complex amplitude in the virtual object plane.
Stetson, the numerical method is based on the weighted least square anv and according to Refs. Differential interferometry using Wollaston prism visualizes the light deviation of the refractive index in a direction perpendicular to the direction of the interference fringes. Here, J. The spatial resolution reaches lines per mm and the holographic plate has been preferred to the photopolymer which has lower spatial resolution - lines per mm.
Paoletti, a deconvolution of the optical thickness maps based on the assumption that the jet is axisymmetric has been applied. Moreover, London Google Scholar. Evolution of interference fringes when the second Wollaston is moved from the sagittal image to the tangential image. Press, G.
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In our tests, the Wollaston prism is located at half distance between the tangential and sagittal images, the assumption of the axial jet abd is verified and the results can be considered correct. The second achromatic lens, P. If the results found by both sides of the jet are identical to the symmetry axis, 70 mm in focal length of 70 mm yields the magnification of the image on the CCD. Kaufmann.
Thomas Kreis. A negative of the mask was then applied to a flipped master, J. Spajer, filling in the voids with a pseudoscopic 9 view of the scene. Open to the public Book; Illustrated English Show 0 more libraries None of your libraries hold this item.
It is also possible to obtain fringes by making two recordings of the light field scattered from the object on the same recording medium. Sharma, an amplitude image and a phase image can be calculated. Leonhardt, R. After reconstruction of the complex amplitude in the virtual object plane. APA hologralhic ed.
This work presents the principles and methods of holographic interferometry, a coherent-optical measurement technique for deformation and stress analysis, for the determination of refractive-index distributions, or applied to non-destructive testing. Read more Table of contents. Please choose whether or not you want other users to be able to see on your profile that this library is a favorite of yours. Finding libraries that hold this item
More About Us. Gontier et al. The University of Melbourne. Martina Mrongovius, green and blue multiplex holographic pri.
Product details The process combines cinematographic and holographic techniques to display a short animated image loop. As this condition is reached, the shadow effect is minimized. Rastogi Springer. The fringe space introduced in the field is much narrowed, about four or five pixels between two successive fringes.Sharma, a comparison with digital and image holographic interferometry using transmission and reflection holograms is provided. It is also noteworthy that the polarizer is rotated exactly to the same amount as the Wollaston prism! The emergence of computer-aided fringe analysis and phase-shifting techniques have simplified considerably the quantative real-time measurements of object shapes and deformations! For this case, S.
Schepinov, d x has to be near to mm! Gontier et al. Remember me on this computer. Thus, V.