US 11,770,955 B2
Organic light emitting display device
Jaeseung Jang, Seoul (KR); Jaeil Song, Gyeonggi-do (KR); and DongHyuk Kim, Seoul (KR)
Assigned to LG Display Co., Ltd., Seoul (KR)
Filed by LG Display Co., Ltd., Seoul (KR)
Filed on Feb. 1, 2021, as Appl. No. 17/164,680.
Application 17/164,680 is a division of application No. 16/423,951, filed on May 28, 2019, granted, now 10,950,665.
Application 16/423,951 is a division of application No. 14/884,952, filed on Oct. 16, 2015, abandoned.
Prior Publication US 2021/0159282 A1, May 27, 2021
Int. Cl. H01L 27/32 (2006.01); H10K 59/30 (2023.01); H10K 50/13 (2023.01); H10K 59/32 (2023.01); H10K 50/11 (2023.01); H10K 50/19 (2023.01); H10K 50/17 (2023.01); H10K 101/00 (2023.01); H10K 101/30 (2023.01); H10K 101/40 (2023.01)
CPC H10K 59/30 (2023.02) [H10K 50/13 (2023.02); H10K 59/32 (2023.02); H10K 50/11 (2023.02); H10K 50/171 (2023.02); H10K 50/19 (2023.02); H10K 2101/00 (2023.02); H10K 2101/30 (2023.02); H10K 2101/40 (2023.02); H10K 2101/90 (2023.02)] 11 Claims
OG exemplary drawing
 
1. An organic light emitting display device, comprising:
an anode;
a first hole transport layer over the anode;
a first light emitting layer over the first hole transport layer;
a first electron transport layer over the first light emitting layer;
a first charge generation layer over the first electron transport layer, the first charge generation layer defining a PN-junction therein;
a second hole transport layer over the first charge generation layer;
a second light emitting layer over the second hole transport layer;
a third light emitting layer over the second light emitting layer;
a second electron transport layer over the third light emitting layer; and
a cathode over the second electron transport layer,
wherein the second light emitting layer includes a hole-type host and a first electron-type host, and the third light emitting layer includes the first electron-type host and a second electron-type host,
wherein an electron mobility of the first electron-type host is lower than an electron mobility of the second electron-type host,
wherein the electron mobility of the first electron-type host is equal to or lower than 1×10−5 cm2/Vs, and the electron mobility of the second electron-type host is within a range from 1×10−5 cm2/Vs to 1×10−4 cm2/Vs,
wherein a LUMO (lowest unoccupied molecular orbital) level of the second electron-type host is lower than a LUMO level of the first electron-type host,
wherein a difference in the LUMO levels between the first electron-type host and the second electron-type host is equal to or less than 0.5 eV,
wherein the LUMO level of the first electron-type host is within a range of −2.3 eV to −2.5 eV and the LUMO level of the second electron-type host is within a range of −2.6 eV to −2.8 eV, and
wherein a HOMO (highest occupied molecular orbital) level of each of the first electron-type host and the second electron-type host is within a range of −5.4 eV to −5.8 eV.