White field brightness

Blue is a unique color in that the z curve of Figure 3, related to the eye s blue sensitivity, is much more remote from the X and y curves than the x and y curves are from each other. The consequence of this is that statements about the brightness of a blue phosphor can be highly misleading. This is because the really meaningful figure of merit for a color TV screen is its white field brightness (WFB). This is defined as lumen output divided by total excitation power (P) incident on all three phosphors while they are excited so as to yield a specified white color. That is. 

MATERIAL RELATIVE BRIGHTNESS COLOR COORDINATES X Y 7 Z RELATIVE ENERGY EFFICIENCY RELATIVE WHITE FIELD EFFECTIVENESS RELATIVE COLOR GAMUT COMMENT... 

In order to reduce the ambient brightness to a minimum, as can be the case in night time road conditions, the light hall was completely darkened. A DIN AO sized test board, which consisted of alternating white and black squares (see Fig. 28), was positioned at a distance of 1.40 m behind the vehicle rear, in order to perform the measurement of the luminance (in candela per square metre (cd/m )) on the individual black or white fields on the monitor and mirror. 

Figure 2.4 (Upper) White-light (polarized) photomicrograph, in reflected mode, of an suspension with a significant emulsified oil content. With polarized light, the clays (C) appear bright, but the oil droplets cannot be seen at all. (Lower) In this reflected-light photomicrograph, of the same field of view as above, the fluorescence mode shows bright oil droplets in a dark water-continuous phase. In this photograph the clays cannot be seen. From Mikula [66], Copyright 1992, American Chemical Society.

FIGURE 8.32 (a) A bright field epi-fluorescence image of two polymorphonuclear white cells (probably neutrophils), (b) The same cells shown in (a) imaged via the Hoechst stain. Note the differences in conformation between the two nuclei. The cell on the top is stuck at the entrance to a channel, and the cell at the bottom is being deformed into a channel. The channels are coated with polyurethane to reduce cell adhesion and to enhance white cell penetration [1175], Reprinted with permission from Springer Science and Business Media. 

To visualize the depolarization fields we may consider the following idea assume we find a molecule with its absorption dipole moment in the plane of the sample. We now adjust the polarization of the excitation beam such that the fluorescence is maximized. We may assume that this happens if the electric field vector in the focus is parallel to the dipole moment. Now, if we turn the incoming polarization by 90° the dominant electric field component will not be able to excite the molecule and the presence of other field components should become visible as weak, but distinctly non-circular spots. Figure 6 shows the result of such an experiment. In Fig. 6(b) the polarization has been turned by 90° as compared to (a) as indicated by the white arrows. The bright spots become dim and their symmetry changes to a four-lobed structure. These weak structures can be made visible if the excitation intensity is increased by a factor of five [see Figs. 6(c) and (d)]. 

Figure 14. Co nanoparticle rings and chains (a) low magnification bright-field image of self-assembled Co nanoparticle rings and chains deposited onto an amorphous carbon support film, where each Co particle has a diameter of between 20 and 30 ran, (b) and (c) magnetic phase contours (128 X amplification 0.049 radian spacing), formed from the magnetic contribution to the measured phase shift, in two different nanoparticle rings. The outlines of the nanoparticles are marked in white, while the arrows indicate direction of the measured magnetic induction [19].

Fig. 7.7. TEM images and SAD patterns (insets) of a poly crystalline ZnO film on silicon (111) PLD grown at 1 x 10 3mbar O2 and about 540°C (a) Bright field Si(lll) plane view observation, grain size is about 70 nm, (b) cross-section HRTEM lattice image with intermediate SiO layer, and (c) weak beam Si(110) TEM cross-section. The area from which the SAD patterns were taken are within the white circles. Reprinted with permission from [49]...

Mitchell The display which for an enchanted two hours followed was such as I find it hopeless to describe in language which shall convey to others the beauty and splendor of what I saw. Stars, delicate floating films of color, then an abrupt rush of countless points of white light swept across the field of view, as if the unseen millions of the Milky Way were to flow in a sparkling river before my eyes... zigzag lines of very bright colors. .. the wonderful loveliness... 

Figure 1 (a) Bright field TEM image in plane view of a porous Si layer with 70 % porosity prepared from p type ( 3.10 n.cm) [100] Si substrate. Pores (in white) are separated by Si walls (in black), (b) Film thickness derived from N2 adsorption isotherm at 77 K for a porous Si layer ( ) extracted from the pore size distribution of cylindrical pores having the same section area as real pores, (o) from the geometrical surface, (a) are film thickness for MCM 41 (5.5 nm). Solid line shows a t-curve obtained by the semi-empirical law FHH and currently proposed to describe adsorption on a non porous substrate. 

Magnesium aluminum silicate occurs as off-white to creamy white, odorless, tasteless, soft, slippery small flakes, or as a fine, micronized powder. Flakes vary in shape and size from about 0.3 X 0.4 mm to 1.0 x 2.0 mm and about 25-240 pm thick. Many flakes are perforated by scattered circular holes 20-120 pm in diameter. Under dark-field polarized light, innumerable bright specks are observed scattered over the flakes. The powder varies from 45 to 297 pm in size. 

---