Interferometry, holographic

There are numerous other inspection techniques that have been developed in the last couple of decades such as holographic interferometry, acoustical holography, acoustic emission, thermal emission scanning, etc. They all have been developed to address shortcomings of more popular inspection techniques but for the most part remain niche techniques. 

There are different techniques to evaluate the quantitative stress level in prototype and production products. They can predict potential problems. Included is the use of electrical resistance strain gauges bonded on the surface of the product. This popular method identifies external and internal stresses. Their various configurations are made to identify stresses in different directions. This technique has been extensively used for over a half century on very small to very large products such as toys to airplanes. There is the optical strain measurement system that is based on the principles of optical interference. It uses Moire, laser, or holographic interferometry (2,3,20). 

Ito, A. and Kashiwagi, T., Characterization of flame spread over PMMA using holographic interferometry, sample orientation effects, Combustion and Flame, 1988, 71, 189. 

Holograms, silver and, 22 639, 657-658 Holographic applications, spectrally sensitized materials for, 9 519 Holographic interferometry, 19 588-589 Holography, optical, 27 421 Holst, Axel, 25 747 Homatropine hydrobromide, 4 360t Homatropine methylbromide, 4 360t Home desalinators, 26 55 Home scrap, 23 261, 262 Home water softeners, 22 818-819 Homobenzoate esters, aroma chemicals, 3 257... 

The application of holography to plasma interferometry has several advantages 276) accurate alignment and precision optical elements are not required. A complete three-dimensional record of the interference phenomena is obtained and the technique is well suited to record stationary and transient plasmas. Two-wavelength holographic interferometry of partially ionized plasmas has been performed by Jeffries 277). 

I ig. 3, Examples of resonant inodes of plale as obtained through time-averaged holographic interferometry. tAfter M. Chant . Xt-ss/mri Coi/>i... 

Non-destructive methods include holographic interferometry, resistance transducers, stress-sensitive covers, and other similar techniques. In practice, the following physical methods of non-destructive monitoring of residual stresses are commonly used X-ray diffraction, measurement of dielectric properties, and ultrasonic control. The main purpose of these methods is to monitor the structural transformations or distortions taking place as a result of residual stresses and local deformations. However, the application of methods such as X-ray diffraction to measure distortions in unit cel dimensions, ultrasonics to measure elastic wave propagation velocities, etc., all encounter numerous experimental problems. Therefore, in ordinary laboratory conditions only quantitative estimations of residual stresses can be obtained. 

For use in write/read/erase memories various organic photo-chromic materials have been studied, and these are described in detail in Section IV. A wide variety of organic materials have been considered for use in permanent memories, all apparently involving some form of photoinduced polymerization, and these are described in Section V. While high sensitivity is desirable in these applications, it is less critical than in holographic interferometry, and in many cases it is not necessary that the material be sensitive in the visible spectral region. 

Sciammarella, C Youngdahl, A. "Application of Laser Holographic Interferometry to Monitor Stone Surface Roughness and Contour Changes" Report to NPS from ANL, in press. 

Differential interferometry in reflected light allows measurement of the shape of the upper reflecting surface. This method was used by Nikolov et al. - " - "" to determine the contact angle, film and line tension of foam films formed at the top of small bubbles floating at the surface of ionic and nonionic surfactant solutions. An alternative method is the holographic interferometry applied by Picard et to study the properties of bilayer lipid membranes in solution. Film... 

To overcome the above limitations, we employ double-exposure holographic interferometry [110]. Holographic techniques have the crucial advantage of storing the full field image of the sample before and after irradiation, thereby permitting spatially resolved characterization of the induced effects over the full sample. The technique is applied to the study of polymeric systems, either in the form of plates or mainly in the form of films cast on transparent substrates. 

R. E. Faw and T. A. Dullforce, Holographic Interferometry Measurement of Convective Heat Transport Beneath a Heated Horizontal Plate in Air, Int. J. Heat Mass Transfer (24/5) 859-869, 1981. 

FIGURE 8-17a Multidirectional holographic interferometry recording and reconstruction system (Ruff and Zhang 1993). (Reprinted by permission of lnt. Soc. of Optical Eng.)... 

Reuss, D. L. "Temperature Measurements in a Radially Symmetric Flame Using Holographic Interferometry." Combustion and Flame 49 (1983) 207-19. 

When diffusion coefficients for BSA were measured in dextran solutions by holographic interferometry, the BSA diffusion coefficient decreased by less than a factor of 2 as dextran concentration was increased from 0 to 0.08 g/mL [54] the diffusion coefficient was not a function of dextran molecular weight (the range tested was 9,300 to 2 x 10 ). The BSA diffusion coefficient was described very well by using Brinkman s equation to estimate the influence of hydrodynamic screening due to dextran molecules in the solution. The dextran fibers were assumed to have a radius of 1 nm the hydraulic permeability, k, of the dextran solution was estimated from the semi-empirical relationship ... 

Kosar, T.F. and R.J. Phillips, Measurement of protein diffusion in dextran solutions by holographic interferometry. AIChE Journal, 1995, 41(3), 701-711. 

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