Patent ID: 8343638

Claim:
An organic light emitting diode comprising: a substrate; a first electrode defining first and second surfaces opposite one another, the second surface facing the substrate; an organic layer facing the first surface of the first electrode; a second electrode defining first and second surfaces opposite one another, the first surface facing the organic layer; and a light-efficiency-improvement layer in contact with at least one of the second surface of the first electrode or the second surface of the second electrode and comprising a compound represented by Formula 1: where Ar is a substituted or unsubstituted C 6 -C 30 aromatic ring system or a substituted or unsubstituted C 2 -C 30 hetero aromatic ring system; each L 1 is independently selected from the group consisting of substituted or unsubstituted C 1 -C 30 alkylene groups, substituted or unsubstituted C 6 -C 30 arylene groups, and substituted or unsubstituted C 2 -C 30 hetero arylene groups; X 1 is N, CY 1 , or a carbon atom bonded to L 1 or Ar; X 2 is N, CY 2 , or a carbon atom bonded to L 1 or Ar; X 3 is N, CY 3 , or a carbon atom bonded to L 1 or Ar; X 4 is N; X 5 is a carbon atom; X 6 is N or CY 6 ; wherein one of X 1 , X 2 , and X 3 is a carbon atom bonded to L 1 or Ar; each of R 1 through R 3 , Y 1 through Y 3 , and Y 6 is independently selected from the group consisting of a hydrogen atom, halogen atoms, a hydroxyl group, a cyano group, substituted or unsubstituted C 1 -C 30 alkyl groups, substituted or unsubstituted C 1 -C 30 alkoxy groups, substituted or unsubstituted C 1 -C 30 acyl groups, substituted or unsubstituted C 2 -C 30 alkenyl groups, substituted or unsubstituted C 2 -C 30 alkynyl groups, substituted or unsubstituted C 6 -C 30 aryl groups, and substituted or unsubstituted C 2 -C 30 hetero aryl groups, wherein two or more adjacent elements selected from R 1 through R 3 , Y 1 through Y 3 , and Y 6 may be bonded to each other to form a saturated or unsaturated ring; a is an integer from 0 to 10; m is an integer from 1 to 5; and n is an integer from 1 to 10.