Optical surface

D. Leger, E. Mathieu and J. C. Perrin, Optical surface determmation usmg speckle correlation technique . Appl. Opt., Vol. 14, 872-877 (1975). 

Caruso F, Jory M J, Bradberry G W, Sambies J R and Furiong D N 1998 Acousto-optic surface-piasmon resonance measurements of thin fiims on goid J. AppL Rhys. 83 1023-8... 

Figure 3 Example of the BRDF characteristic of a polished optical surface. Note the rapid increase in scattering at small scatter angles.

Tor the purpose of this brief account we will provide only a notional definition of optical aberrations. In an optical system, the angular coordinates of incident rays are transformed according to sequential applications of Descarte s law from one optical surface to the next. Aberrations are essentially the non-linear terms of the transformation, the angular coordinates of emerging rays not being strictly proportional to those of the incident ones -thereby generating distorted and/or blurred images. 

Due to diffraction effects of micron-sized mirrors in a regular array, commonly used techniques for surface characterization based on interferometry are inefficient. To overcome the diffraction effects we have developed a novel surface characterization method with an incoherent light source, based on the Foucault s knife-edge test (Zamkotsian and Dohlen, 1999). Since Leon Foucault introduced the knife-edge test in the last century (Foucault, 1859), it has been widely used for testing optical surfaces (see Ch. 3). The test offers a simple way of obtaining easily understandable, qualitative information of the surface shape. 

Metal atoms can be incorporated into polymers using two approaches. For probing new reactions between metal atoms and polymers a small-scale spectroscopic approach, sometimes referred to as the Fluid Matrix Technique (11), is used. The coreactant polymer matrix, containing on the order of 0.5 fll of polymer, is preformed on an optical surface. In the case of viscous fluids such as 2 the material is painted on the substrate and held at temperatures ranging typically from 200 to 270 K. The temperature is chosen to maintain low volatility but retain mobility. Under high vacuum [10 6 torr]... 

It is through the solid state characteristics of polymers that we - as users - primarily interact with them. For convenience, we can divide the principal properties of polymers into five categories mechanical, optical, surface contact, barrier, and electrical. Weather resistance is a sixth category that can influence each of the other five categories. In order to understand these properties we must be able to quantify them. In this chapter we shall concentrate on measurement techniques, since it is through these methods that we learn how a polymer will behave during use. 

Spectrophotometer cell, n - an apparatus which allows a liquid sample or gas to flow between two optical surfaces which are separated by a fixed distance, referred to as the sample pathlength, while simultaneously allowing light to pass through the liquid. There are variations of this including variable-pathlength cells, and multi-pass cells, and so on. 

U. Kunz, A. Katerkamp, R. Renneberg, F. Spener, and K. Cammann, Sensing fatty acid binding protein with planar and fiber-optical surface plasmon resonance spectroscopy devices. Sens. Actuators B 32, 149-155 (1996). 

Sumetsky, M. Dulashko, Y. DiGiovanni, D. J., Optical surface microscopy with a moving microsphere, In Nanophotonics Topical Meeting, OSA, Uncasville, 2006... 

The highest phonon frequency measured so far has been reported for NaF(lOO). By using primary beam energies of 90meV, Brusdeylins et al. have detected optical surface modes with frequencies of 40meV. The intensities, however, were rather low and the multiphonon background dominated the energy loss spectra. 

R. D. Harris, B. J. Luff, J. S. Wilkinson, J. Piehler, A. Brecht, G. Gauglitz, and R. A. Abuknesha, "Integrated Optical Surface Resonance Immunoprobe for Simazine Detection," Biosensors Bioelectronics 14, 3635-3641 (1999). 

In some cases, the sample will deposit a film onto the optical surfaces of a probe or cell. This film might lead to a bias in the analytical results, and eventually could reduce hght transmission to make the analysis impossible. Film buildup requires some action be taken to clean the cell or the probe, either cleaning in place or by removing the probe or cell for cleaning by hand. 

Various methods to achieve stray light reduction include spectrometer interior redesign improved optical surfaces (e.g. gratings) and modifications of the dispersion... 

Bokken, G. C. A. M., Corbee, R. J., van Knapen, F., and Bergwerff, A. A. (2003). Immunochemical detection of Salmonella group B, D and E using an optical surface plasmon resonance biosensor. FEMS Microbiol. Lett. 222, 75-82. 

Slavik, R., Homola, J., and Brynda, E. (2002). A miniature fiber optic surface plasmon resonance sensor for fast detection of staphylococcal enterotoxin B. Biosens. Bioelectron. 17, 591-595. 

The final silver cluster diameter increases, at given initial Ag and PVA concentrations, for example from 15 to 50 nm (n 50 times larger), when the part of reduction is increasingly achieved by the donor SPV, rather than by radiolytic radicals [31]. A red shift correlates with the growth in size in the final optical surface plasmon band. Nonirradiated solutions of EDTA silver complex are stable because EDTA does not reduce the ions directly. However, after the appearance of the 400-nm spectrum of silver... 

Optical characteristics of the solid filter are different from typical samples, which are usually in solution form. Recertification required Possible interreflections between optical surface Optical characteristics of the solid filter are different from the samples, which are usually in solution form Recertification required... 

When using optical filters for photometric accuracy measurements, make sure that the filter is placed properly in the sample holder so that the filter is perpendicular to the incident light beam. Problems of reflection from the highly polished surface of the glass filter and interreflection between optical surfaces for metal on quartz filters may occur that affect the readings. 

Reasonable care must be taken in handling salt cells and plates. Moisture-free samples should be used. Fingers should not come in contact with the optical surfaces. Care should be taken to prevent contamination with silicones, which are hard to remove and have strong absorption patterns. 

A grating ruled on a spherical surface combines the properties of the diffraction grating with the focusing ability of the optical surface. Such a device, with radius of curvature R, focuses spectra as images of the entrance (primaiy) slit on the circumference of a circle of diameter R, when the entrance slit is also located on the circumference of the circle.z... 

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