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In the commonly-used EDA software, there is no equivalent circuit model of top-emitting OLED for SPICE, so it is difficult while the OLED pixel driving circuits are designed such as in microdisplay applications. To solve the problem, its SPICE model of top-emitting OLED was studied in this paper. Three models including the diode-connected NMOS model, the single-diode model, and the double-diode paralleled model are discussed and their simulation results from EDA software HSPICE are compared. Results show that the fitted errors obtained from the diode-connected NMOS model is the smallest, but its simulated errors are the largest. The fitted errors and the simulated errors obtained from the single-diode model are also large. However, small fitted errors and simulated errors got from double-diode paralleled model show that this model satisfies the application of the designing for OLED pixel driving circuits.

By application of clad-bonding technique of pure copper sheet and plain low carbon steel rebar Q195, the cladding wires in different diameter by drawing at room temperature have been worked. The increasing ratio of the area of grain boundary is in direct proportion to deformation approximately. The resistivity of the cladding wires go up in direct proportion to deformation because the increment of the area of grain boundary results in increment of static disfigurement to electron dispersion. When deformation is less 9.6, the relative increment of resistivity is less 1.1%, i.e. the wire is provided with good electrical conductivity. And the resistance and resistivity of the wires can be estimeted based on copper ratio of transverse section of the cladding wire and the deformation by drawing at room temperature.

The microstructure and mechanical properties of pure copper clad Aluminum wires in different diameters by drawing at room temperature were studied in this paper. The results show that the microstructure of the cladding wire by drawing at room temperature is vimineous grain as fibril shape from prime equiaxed grain. The fibril diameter is in inverse proportion to deformation and the fibril length is in direct proportion to square of deformation approximately. The ultimate tensile strength of the cladding wire by drawing at room temperature increases in direct proportion to square root of deformation, and the elongation decreases and fluctuates. Basis of the ultimate tensile strength of prime pure copper and aluminum alloy, the ultimate tensile strength of the cladding wires in different diameters can be doped out by mixed principle of composite material.

Fracture surface and crack propagation in low temperature brittle fracture (LTBF) of an 18Cr-18Mn-0.7N high nitrogen austenitic steel (HNAS) were examined by means of scanning electronic microscopy, and compared with behaviours of LTBF of low carbon steel. Similar to BCC low carbon steel, the HNAS experienced a typical ductile-to-brittle transition (DBT) with decreasing temperature, and the appearance of the fracture surface transited from fibrous to granular. Dual-surface observation revealed that there were three types of fracture modes in LTBF of the HNAS: annealing twin boundary fracture, intergranular fracture, and transgranular fracture. The annealing twin boundary fracture facets were parallel to {111} planes, and were fairly flat and smooth, with a pattern of three sets of parallel straight-lines intersecting at 60. There were also bent steps that originated and terminated at grain boundaries. The transgranular fracture facets were coarse and uneven, with uniformly distributed small pits and partially river pattern on them. The intergranular fracture facets were smoothly curved ones on which more than three sets of parallel deformation structure trace lines were observed. Careful observation on crack propagation demonstrated that during LTBF of the HNAS, microcracks formed firstly at grain boundary and annealing twin boundary, and then these microcracks came together and coalesced to induce crack propagation through grains, resulting in a fracture appearance with shiny facets distributing in dull facets.

Non-doped type white organic electroluminescent (EL) devices have the following structure ITO/m-MTDATA (30nm) /NPB (20-dnm) /rubrene (0.1nm) /NPB (dnm) /DPVBi (20nm) /TPBi (20nm) /Alq (10nm) /LiF/Al were fabricated. The EL spectrum of the devices are dependent on the d and when d=3, the CIE coordinates of the device were well within the white region for voltage raging from 3V to 15V. This device has a luminance of 18950cd/m2 at 15V and maximum power efficiency of 5.65cd/A at 6V.

A novel derivative of oligo(phenylenvinylene) (OPV), 2,5-diphenyl -1, 4-distyrylbenzene with two trans-double bonds (trans-DPDSB), is used as a blue emitting material in blue and white organic light-emitting devices (OLEDs). Blue devices with a configuration of indium-tin oxide (ITO)/N,N´-diphenyl-N,N´-bis(1-naphthyl)-(1,1´-biphenyl)-4,4´-diamine (NPB)/ trans-DPDSB / tris (8-hydroxyquinoline) aluminum (Alq3)/LiF/Al are constructed, where NPB, Alq3 and trans-DPDSB are used as hole-transporting, electron-transporting and light-emitting layers, respectively. The color of emission is changed from blue-green to pure blue when the trans-DPDSB layer is thicker. By inserting an ultrathin 5,6,11,12-tetraphenylnaphthacene (rubrene) yellow light-emitting layer between the Alq3 and trans-DPDSB layers, white OLEDs are obtained. The maximum efficiency and luminance of the blue and white devices are 1.2, 3.0 cd/A, and 1400, 7000 cd/m2, respectively.

In this paper, we describe the performance of an organic light emitting devices〔OLEDs〕 with ITO /4,4’,4“-tris{N,- （ 3-methylphenyl ） -N-phenylamino}triphenylamine (m-MTDATA) /N,N-diphenyl-N,N-bis1-naphthyl-1,1-biphenyl-4,4-diamine (NPB) /copper phthalocyanine (CuPc) / NPB / Bathocuproine(BCP) / tris-8-hydroxyquinoline Aluminum (Alq3) / LiF/ AL structure, the CuPc inserted between the two layers of NPB as a hole-consuming layer (HCL), and the BCP as a hole-blocking layer (HBL) . The EL spectrum peak is at 430 nm, indicating that the carrier recombination is confined in the NPB layer, in additional light emission originates from NPB. Compared with the luminous efficiency of the conventional diode without CuPc layer, that of the diode with HCL has been sharply increased up to 2.62 cd /A. It suggested that the CuPc and BCP exactly function as hole-consuming and hole-blocking layers, respectively, which enhance the efficiency of carrier，s recombination and confine the excitation in the EL layer.

We have fabricated an organic light-emitting devices with high efficiency and brightness utilizing thick layer of a starburst amine compound 4,4’, 4’’-tris{N,-(3-methylphenyl)-Nphenylamin} triphenylamine (m-MTDATA) as hole injection buffer layer. The brightness and the current efficiency were comparatively improved compared with those of the device without the buffer layer. The device with 10nm m-MTDATA act as buffer layer has max brightness was 18590cd/m2 at 17 V, and the highest luminous efficiency was achieved 4.30cd/A, at 7V, which is nearly three times than that of the device without it.

we designed and fabricated a white organic light-emitting device based on{[2-methyl-6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9yl)ethenyl]-4H-pyran-4-ylidene] propane-dinitrile}ultrathin layer and 4,4 ´ -bis(2,2 ˊ diphenylvinyl)-1,1 ˊ -biphenyl. It shows a maximum power efficiency of 1.8l m/W at 4 V (the brightness is 51 cd/m2). Its brightness reaches 8496 cd/m2 at 16 V. And the chromaticity coordinates varying from (0.42,0.34) to (0.32,0.28) with the forward bias from 4 to 16 V are well within the white region.

The lifetime of organic light-emitting devices can be influenced by the OLED material and structure, electrode material, driving mode and so on. Among all these factors, OLED driving method has been regarded as one of the most important factors, and it is well known that ac-driving mode improves the lifetime of OLED, especially pulse-driving mode with a reversed-biased voltage on OLED. In this article, a new ac-driving mode for Active-Matrix OLED is proposed on basic fabrication of two-TFT current source pixel circuit. Simulation has been done on the pixel and 1×4 matrix circuits, and simulation results have demonstrated that OLED is in reversed-biased state during recovery time. At last, a practical peripheral circuit that can provide achieve an ac-driving mode has been designed.