Illumination quality

A.R. Duggal, J.J. Shiang, C.M. Heller, and D.F. Foust, Organic light-emitting devices for illumination quality white light, Appl. Phys. Lett., 80 3470-3472 (2002). 

If the IBP is high, the kerosene will not be volatile enough to provide good flame height and illuminating quality. 

Candle Power - The illuminating power of a standard candle employed as a unit for determining the illuminating quality of an illuminant. 

Bertrand lens n. An auxiliary, low-power lens which maybe inserted in the bodytube of the microscope between the eyepiece and the objective for observing the back focal plane of the objective useful for conoscopic observations in crystal optics and for checking microscope illumination quality. 

Quality of Lighting The quality of lighting may affect error rates and cause accidents. For many applications control of illumination levels alone is not sufficient. Designs must control illumination quality as well. For example, users of computer screens are more likely to experience eye strain and other visual problems when there are combinations of poor reflectance, brightness ratio, and contrast ratio. 

Under Httle or no illumination,/ must be minimized for optimum performance. The factor B is 1.0 for pure diffusion current and approaches 2.0 as depletion and surface-mode currents become important. Generally, high crystal quality for long minority carrier lifetime and low surface-state density reduce the dark current density which is the sum of the diffusion, depletion, tunneling, and surface currents. The ZM product is typically measured at zero bias and is expressed as RM. The ideal photodiode noise current can be expressed as follows ... 

People differ in their preferences and m the value they put on their time. For consumer choices in particular, the entire list of qualities of services provided by different energy sources can be important. For example, both kerosene lamps and electric lights can be used to illuminate a home. Most households shifted quickly to electricity once it became available, and few would shift to kerosene today even if kerosene for lamp fuel were free. The lighting provided differs in more ways than cost. 

The energy threshold appears to be dependent on the excitation spot size at constant pump intensity, which indicates that amplification occurs over the whole illuminated area. It should be stated that, despite the large domains, the optical quality within the domains is lower than that of the annealed films. This gives rise to additional scattering losses which decrease the magnitude of the amplification. 

The indirect methods discussed thus far have dealt with measurement of color only as it can be correlated with physical characteristics of materials and the effect of these materials on radiant energy. As has been pointed out, the reflectance spectro-photometric curve describes a property of the material. A change in the reflectance spectrophotometric properties may not always result in a change in visual color. The reason is that color of the object is not an unchangeable characteristic of the object itself, dependent only upon these reflectance properties, but is also dependent upon the quality of the illuminating light and the sensitivity of the observer s eye. Thus the measurement and description of visual color are psychophysical problems... 

The application of infrared photoacoustic spectroscopy to characterize silica and alumina samples is reported. High quality infrared photoacoustic spectra illuminate structural changes between different forms of silica and alumina, as well as permit adsorbate structure to be probed. Adsorption studies on aerosil suggest adsorbed species shield the electric fields due to particle-particle interactions and induce changes in the vibrational spectra of the adsorbates as well as in the bulk phonon band. It is shown that different forms of aluminum oxides and hydroxides could be distinguished by the infrared spectra. 

Cosine smearing. Because instrument volume and experiment time must both be minimized for a planetary Mossbauer spectrometer, it is desirable in backscatter geometry to illuminate as much of the sample as possible with source radiation. However, this requirement at some point compromises the quality of the Mossbauer spectrum because of an effect known as cosine smearing [327, 348, 349] (see also Sects. 3.1.8 and 3.3). The effect on the Mossbauer spectrum is to increase the linewidth of Mossbauer peaks (which lowers the resolution) and shift their centers outward (affects the values of Mossbauer parameters). Therefore, the diameter of the source y-ray beam incident on the sample, which is determined by a... 

Precursors obtained with various anions should be studied at comparable conditions, and the quality of target products should be compared in order to illuminate the role of anion in thermal decomposition processes. 

Cogswell, C. J. and Larkin, K. G. (1995). The specimen illumination path and its effect on image quality. In Handbook of Biological Confocal Microscopy (Pawley, J. B., ed.). Plenum press, New York, pp. 127-37. 

Measures in UV reflectivity mode are thus possible, using a 400 nm peaked narrowband filter. However, because of the glass optics absorption below 400 nm and the low sensor sensitivity in the UV, the quality of the images in UV reflection mode is not particularly good, because of the long exposure time need for compensating the low illumination on the sensor. 

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