Figure 4

Device structures of (a) OLEDs and (b) QLEDs. (c) Normalized EL spectra of green OLED and QLED. (d) CIE 1931 color coordinates for EL spectra of OLED and QLED without (w/o) and with (w/) human finger. Normalized EL spectra of (e) OLED and (f) QLED w/o and w/ human finger.