A.W. Koch, P. Evanschitzky, M. Jakobi
The current technical set-up of speckle interferometry is based on temporal phase-shifting with a single CCD camera, which requires a vibrationisolated environment. In order to apply the phase-shifting technique to an industrial environment, without any vibration isolation, four phase-shifted speckle images are simultaneously acquired by means of four cameras. In order to achieve this aim we use four parallel speckle interferometers. The appropriate phase differences between the beams are realized by variable path differences employing movable prisms. This new laboratory set-up demonstrates...
XVI IMEKO World Congress
· TC2
· 2000
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B. Journet, J.C. Lourme
The purpose of the paper is to present a new laser diode range finding method. The system belongs to the category of flight time measurement. The optical power of the laser diode beam is modulated and then both emitted and returned signals are compared in order to obtain the delay or distance information. The new method is an estimation of the distance by correlation computation. The main advantages of this method are presented by simulation studies showing the robustness of the method towards noise and coupling phenomena. Then a prototype is presented associating the optical head and a...
XVI IMEKO World Congress
· TC2
· 2000
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K. Iwata, H. Kikuta, T. Kondo, A. Mizutani
This paper describes a shearing interferometer with four diffraction gratings for dividing light waves. It allows us to use an extended white light source. This feature of the interferometer is discussed and demonstrated by experiments. By constructing the interferometer for testing transparent object, phase distribution of the light wave passing through an optical lens is measured with a halogen lamp source. By modifying it for the reflecting object, profile of a curved mirror is measured.
XVI IMEKO World Congress
· TC2
· 2000
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P. Greguss
In robotics, the need for space mapping means to acquire not only intensity- bound data from the optical signal, which then can be processed to become information, but also data bound to the phase of the signal carrier is of importance. The main objective of this paper is to introduce a new concept for mapping strategy, the so-called centric minded imaging (CMI) on one side, while, on the other side, to demonstrate how this concept has already been applied to robotics in a broad sense, further, which is the situation at present, and what can be expected in the future. Topics such as space...
XVI IMEKO World Congress
· TC2
· 2000
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K. T. V. Grattan
Developments in the field of fibre optics and lasers in recent years have had a very major impact upon the creation of fibre optic-based sensor systems, used for a variety of measurement and instrumentation applications. This paper will review some of the most relevant of these recent developments and discuss the prospects for and new horizons in fibre optic sensors into the future.
XVI IMEKO World Congress
· TC2
· 2000
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I. V. Golubev, E. V. Sysoev, Y. V. Chugui
Profile measurement of the surface defects (with the depth of dozens of microns), based on the low-coherent interferometry, is discussed in this paper. The major challenge for production of such devices is selecting interference zones, which are used to determine the isolines of the defect depth. A direct way to find lowcontrast interference zones in a large dynamic light range appears to be an extremely difficult procedure. We propose an effective interference zones localization technique based on the reference wave phase modulation that against others provides high measurement accuracy and...
XVI IMEKO World Congress
· TC2
· 2000
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S. Deng, Q. Zhao, H. Zhang
As the high rotating speed of air bearing in astronautic gyro, the geometrical parameters (radius, sphericity) of its hemispherical contour must be with ultrahigh accuracy in the order of sub-micrometer. The non-contact pneumatic measurement technique is applied. In this paper, a new type of “air-pin” so-called pneumatic electronic sensor developed by the authors is introduced first. This sensor consists of fine nozzle of less than 0.15 mm in diameter, and its measurement resolution is 0.01 µm, measurement repeatability is within ± 0.05 µm. The spherical pneumatic gauge with multi-nozzles...
XVI IMEKO World Congress
· TC2
· 2000
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Y. Deguchi, S. Iwasaki, K. Yoshikawa, H. Moritomi, K. Matsumoto
A LIBS technique has been applied to detect alkali metals under high pressure and high temperature conditions, and an automated LIBS unit has been developed and applied in a month-long monitoring experiment. The results were compared to those obtained using the conventional sampling method, showing good agreement. LIBS can detect Na and K at ppb levels, even under the high pressure conditions appearing in PFBC and IGCC thermal power plants. LIBS is capable of 1 minute detection time, as compared to the 20 hour sampling time required by the conventional method, and offers various merits as a...
XVI IMEKO World Congress
· TC2
· 2000
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A. Cysewska-Sobusiak, G. Wiczynski
The subject of the paper is focused on novel utilization of super-efficient light-emitting diodes (LEDs) as measuring sources of optical radiation when the determined current pulses are used to drive them. The relationships between input electrical pulse parameters, such as the amplitude and duty factor, and output optical power are studied. Results of LEDs dynamics analysis and experiments made on representative elements are reported. An especially designed generator was used to obtain standard rectangular current pulses needed to evaluate LEDs optical responses.
XVI IMEKO World Congress
· TC2
· 2000
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Y. V. Chugui, A. A. Pavlov
The detailed analysis of diffraction pattern in far zone for circular absolutely reflecting metal cylinder with regard to the influence of wave reflected from its surface is presented. The method of stationary phase was used when calculating the reflected component of the input field. The behaviour of diffraction pattern minima for wide range of angles is studied. The formula for angular position of minima in case of small observation angles was found. Three algorithms of cylinder diameter reconstruction using its diffraction pattern were proposed. They allow theoretically to increase...
XVI IMEKO World Congress
· TC2
· 2000
· Download