Transmission color

The simulation discussed above was based on full color produced by individual red, green, and blue emitters. Other full-color reproduction approaches have been proposed for OLED displays including color from blue emitter by means of energy down conversion fluorescent filter [177], and color from white emitters by means of transmission color filter sets similar to that used in LCD industry [178,179]. Table 1.5 compares the EL efficiency of equivalent white... 

Optical properties Refractive index Dispersion Reflection Refraction Absorption Transmission Color... 

Optical Tests. Refractive index, light transmission, color range, scattering, light fastness. 

At the specular angle we see the blue from the interference pigment. At the diffuse angle we see the red from the absorption colorant which has been precipitated on the surface. By transmission, a third color is formed which is not often seen unless coated on a transparent substrate such as glass or Mylar. The transmission color from the interference pigment which is yellow has combined with the absorption colorant which is red to form a third color which is orange. 

When measurements were made at -15/15, a black card was placed behind the coated glass slides to eliminate the effect of the transmission color. When measurements were made at -15/60, a white card was placed behind the coated glass slide. A diagram demonstrating the position of the slides and the cards is shown in Figure 7. 

In Table 1, examples are shown where the colorant which was added to the interference pigment had a color which was different from the transmission color of the interference pigment. In all these cases a new third color was formed. 

In Table 2, examples are shown where the colorants added to interference pigments had the same color as the transmission color. An enhancement of that color resulted as may be expected. A reinforced yellow, red, blue and green resulted. 

Colorant added Reflection color Transmission color Third color... 

As can be seen in the table, the first two examples yielded a neutral white. The yellow colorant combined with the blue transmission color resulting in a neutral white. The red colorant combined with the green transmission color resulting in a neutral white. 

In the last two examples in the table, the blue colorant combined with the yellow transmission color resulting in a blue-green color and the green eolorant eombined with a red transmission color to yield an orange. 

Kumar and Reynolds also showed that PEDOT can be used as a cathodically coloring polymer in dual polymer electrochromic devices that have both transmissive color-neutral and absorptive highly colored states [74]. Dietrich et al. compared the electrochemical and optical properties of PEDOT and PProDOT [75]. 

Separation Test Homogeneous from 10C-40C Dilution Test 90% Min., light transmission Color 150 Platinum-Cobalt, Max. 

Also, the optical state (transmission, color) is very often practically the same on both sides of a zigzag wall, as in Fig. 93b. Indeed, if the director lies parallel to the surface (pretilt o =0) at the outer boundaries, the chevron looks exactly the same whether the layers fold to the right or to the left. However, if the boundary condition demands a certain pretilt a 5 0, as in Fig. 105, the two chevron structures are no longer identical. The director distribution across the cell now depends on whether the director at the boundary tilts in the same direction relative to the surface as does the cone axis, or whether the tilt is in the opposite direction. In the first case we say that the chevron has a C1 structure, in the second a C2 structure (see also Fig. 106). We may say that the Cl structure is natural in the sense that if the rubbing direction (r) is the same at both surfaces, so that the pretilt a is symmetrically inwards, the smectic layer has a natural tendency (already in the SmA phase) to fold accordingly. However, if less evident at first sight, the C2 structure is certainly possible, as demonstrated in Figs. 105 and 106. 

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