The most important single principle in the use of color is that whenever detailed information is to be shown, luminance contrast is necessary.
We have fabricated efficient blue organic light-emitting devices (OLEDs) with 4,4′-bis 9-ethyl-3carbazovinylene -1,1′-biphenyl BCzVBi 9-ethyl-3carbazovinylene -1,1′-biphenyl BCzVBi 9-ethyl-3carbazovinylene -1,1′-biphenyl BCzVBi 9-ethyl-3carbazovinylene -1,1′-biphenyl BCzVBi 9-ethyl-3carbazovinylene -1,1′-biphenyl BCzVBi asd luminous efficiency are greathe enhanced in the doped devices.
In [18], it shows that luminance masks have little effect on color contrast detection while chromatic masks greatly affect the detectability of luminance contrast.
Figure 5 shows that luminance efficiency versus current density curves of a DB3 ZnO device before and after annealing.
DB3 ZnO device shows maximum luminance efficiencies (1.78 cd/A) and with annealing (2.45 cd/A) having a brightness 643 and 776 cd/m2at a current density of 36.16 and 31.67 mA/cm2, respectively.
The maximum brightness of the DB4 ZnO reaches 9,490 cd/m2 (7.51 V), which is much higher than that of DBPPV (5,004 cd/m2 at 7.41 V). Figure 2a shows the luminance efficiency versus current density characteristics for the devices.
The device with III as the electroluminescent layer shows a luminance of 800 Cd/m2 at 10 V with conversion efficiency of 0.5 Lm/W, whereas the device with IV as the electroluminescent layer demonstrates somewhat lower characteristics, viz., 200 Cd/m2 at 13 V.
It is noted that the transmittance as well as the brightness of the devices in the whole visible region should be taken into account to completely understand the transmittance effect on the brightness of the devices, not only at 588 nm. Figure 9 shows the luminance decay curve as a function of time for the device based on 100-nm-height TiO2 nanorods.
Figure 7 shows the luminance-voltage performance of devices with different films as hole injection layers.
Blue dotted lines show actual luminance observations in all three plots.
