TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation: No general preparation given. Preferred Compounds: The polycyclic compound (1) is preferably chosen from 15 polycyclic compounds, such as compounds of formulae (5,7,13), more preferably of formulae (15,17). The polycyclic compound (2) is preferably chosen from 25 polycyclic compounds, such as compounds of formulae (6,10,25), more preferably of formulae (16,18,24). The halogen compound (30) is preferably of formulae (32-37).X5-X8=X1;m1-m8=0 or 1;m1+m2=1;m5+m6=1 or less;andm6+m7+m8=1 or less.N-R1 of X5 and N-R1 of X6 are different. Preferred Layer: The light emitting layer contains polycyclic-type compound as host material, and further contains phosphorescence luminosity material chosen from ortho metalation complex of platinum, iridium and osmium. An electron injection layer containing a nitrogen-containing ring derivative, and electron carrying layer containing polycyclic-type compound are provided between light emitting layer and cathode. A hole transport layer containing polycyclic-type compound is provided between light emitting layer and anode. A reducing dopant is provided in interface region of cathode and organic thin film layer. Full Definitions:    Ar1-Ar3=6C optionally substituted aromatic hydrocarbyl or aromatic heterocyclic group, and optionally have substituent (Y);    Y=1-20C alkyl, 3-20C optionally substituted cycloalkyl, 1-20C alkoxy, 7-24C aralkyl, silyl, 3-20C substituted silyl, 6-24C optionally substituted aromatic hydrocarbyl or 3-24C optionally substituted aromatic heterocyclic group connected by Ar1-Ar3 and carbon-carbon bond;    X1-X4=oxygen, sulfur, N-R1 or CR2R3;    R1-R3=1-20C alkyl, 3-20C optionally substituted cycloalkyl, 7-24C aralkyl, silyl, 3-20C substituted silyl, 6-24C optionally substituted aromatic hydrocarbyl or 3-24C optionally substituted aromatic heterocyclic group;    o-q=0 or 1;    s=1-3;    n=2-4;    L1=single bond, 1-20C alkylene, 3-20C optionally substituted cycloalkylene, 2-20C optionally substituted bivalent silyl, 6-24C bivalent aromatic hydrocarbyl or 3-24C optionally substituted monovalent or bivalent aromatic heterocyclic group connected with Ar1 by carbon-carbon bond;    L2=single bond, 1-20C alkylene, 3-20C optionally substituted cycloalkylene, 2-20C optionally substituted bivalent silyl, 6-24C bivalent aromatic hydrocarbyl or 3-24C optionally substituted bivalent aromatic heterocyclic group connected with Ar3 by carbon-carbon bond;    A1=H, 3-20C optionally substituted cycloalkyl, 3-20C optionally substituted silyl, 6-24C aromatic hydrocarbyl or 3-24C optionally substituted aromatic heterocyclic group connected with L1 by carbon-carbon bond;    A2=H, 3-20C optionally substituted cycloalkyl, 3-20C optionally substituted silyl, 6-24C aromatic hydrocarbyl or 3-24C optionally substituted aromatic heterocyclic group connected with L2 by carbon-carbon bond;    Y1-Y3=1-20C alkyl, 3-20C optionally substituted cycloalkyl, 1-20C alkoxy, 7-24C aralkyl, 3-20C silyl, 6-24C optionally substituted aromatic hydrocarbyl, or 3-24C aromatic heterocyclic group connected with benzene rings (a-c) by carbon-carbon bond;    d,f=0-3;and    e=0-2.    When n is 2, L3 is L2, when n is 3, L3 is 1-20C trivalent saturated hydrocarbyl, 3-20C optionally substituted trivalent cycloalkane, trivalent silyl, silyl or 1-20C trivalent substituted silyl, 6-24C optionally substituted trivalent aromatic hydrocarbyl, or 3-24C optionally substituted aromatic heterocyclic group connected with Ar3 by carbon-carbon bond, and when n is 4, L3 is 1-20C tetravalent saturated hydrocarbyl, 3-20C optionally substituted tetravalent cycloalkane, silicon atom, 6-24C optionally substituted tetravalent aromatic hydrocarbyl, or 3-24C optionally substituted aromatic heterocyclic group connected with Ar3 by carbon-carbon bond. A1,A2,L1-L3 do not contain a carbonyl group. When L2 is 1-20C alkyl or alkylene, A2 is not contained, and when A1,A2 are H, p and q are 0. When L1,L3 are 6-24C optionally substituted bivalent, trivalent or tetravalent aromatic hydrocarbyl, X1 and X3 are CR2R3, p,q are 0, and q is 1. Preferred Definitions:    A1 and/or A2=pyrimidyl, triazyl, fluorenyl, carbazolyl or dibenzo furanyl having substituent chosen from phenyl, biphenyl, terphenyl and/or quaterphenyl, and are aromatic hydrocarbyl having structure, in which 2 or more benzene rings are coupled by meta position;    n=2;and    X1-X4=N-R1 or oxygen, and at least one of R1 is dibenzofuran residue or carbazole residue.    N-R1 of X1,X2 and N-R1 of X3,X4 are different.    SPECIFIC COMPOUNDS - Five hundred and sixty eight polycyclic compounds, such as 9-phenyl-3-(16-(9-phenyl-9H-carbazol-3-yl)-3,20-dioxapentacyclo(11.7.0.02,10.04,9.014,19)icosa-1(13),2(10),4,6,8,11,14(19),15,17-nonaen-7-yl)-9H-carbazole of formula (A), 3,20-bis((8-oxatricyclo(7.4.0.02,7)trideca-1(9),2,4,6,10,12-hexaen-4-yl))-3,20-diazapentacyclo(11.7.0.02,10.04,9.014,19)icosa-1(13),2(10),4(9),5,7,11,14(19),15,17-nonaene, 3-(4-(9H-carbazol-9-yl)phenyl)-20-(8-oxatricyclo(7.4.0.02,7)trideca-1(9),2,4,6,10,12-hexaen-4-yl)-3,20-diazapentacyclo(11.7.0.02,10.04,9.014,19)icosa-1(13),2(10),4(9),5,7,11,14(19),15,17-nonaene, 3-(8-oxatricyclo(7.4.0.02,7)trideca-1(9),2,4,6,10,12-hexaen-4-yl)-20-phenyl-3,20-diazapentacyclo(11.7.0.02,10.04,9.014,19)icosa-1(13),2(10),4(9),5,7,11,14(19),15,17-nonaene and 3-(3-(9H-carbazol-9-yl)phenyl)-20-(8-oxatricyclo(7.4.0. 02,7)trideca-1(9),2,4,6,10,12-hexaen-4-yl)-3, 20-diazapentacyclo(11.7.0.02,10.04,9.014,19)icosa-1 (13),2(10),4(9),5,7,11,14(19),15,17-nonaene are disclosed.    EXAMPLE - 11,12-Dihydro-11,12-diaza-indeno(2, 1-a)fluorene (in g) (2.6), 2-bromo dibenzofuran (5), copper iodide (1.9), cyclohexane-1,2-diamine (3.4), potassium phosphate (8.5) and 1,4-dioxane (10 ml) were added to a flask, and stirred under argon atmosphere for 10 hours. The mixture was cooled to room temperature, and water (50 ml) was added. The resulting product was extracted to obtain a polycyclic compound (0.7) at yield of 12%.