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A green organic light emitting device(OLED) with the structure of ITO/MoO3(x nm)/N,N′-diphenyl-N,N′-bis(1-naphthyl)-(1,18-biphenyl)-4,4-diamine(NPB)(40 nm)/tris(8-hydroxyquinoline)aluminum(Alq3)(60 nm)/LiF(1 nm)/Al(150 nm) have been fabricated by vacuum deposition method,x=0,5 nm.The detail process has been described.It was found that the treatment on the surface of ITO substrates by oxygen plasma can effectively reduce the contact angle of the ITO surface in the experiments.By measuring and analyzing the performance of luminescence and electrical of device,the influences of the hole injection layer MoO3 on device performance was investigated.Experimental results show that HOMO level of MoO3 can reasonably match ITO work function,which reduces the hole-injecting barrier and improves the brightness and efficiency of device.When forward voltage is less than 10 V,the current density of device does not change significantly with the voltage increases;When the voltage is more than 10 V,the current density increases significantly.The chroma of device stabilizes in green light district of(0.36,0.55) with the changes of the driving electric voltage.

Considering narrow temperature and viewpoint of LCD for most portable display system,OLED is used as display device.Focusing on the problem of low contrast of generic driver method for portable display system,a new driver based on FPGA is introduced which can improve the flexibility of the system.As the MCU,PIC16F690 takes control of system sequence.While FPGA mainly handles video processing work,including color standard converting,color gamut dealing,interlaced video to progressive video.Results show that the contrast is improved dramatically,images displayed stably.The design provides a platform for future.

Various morphology ZnO submicrorods and microrods have been fabricated onto glass substrates through chemical solution growth by the source of zinc acetate (Zn(CH3COO)2.2H2O) and hexamethylene tetraamine ((CH2)6N4). We discuss the influence of PH and the concentration of the solution on the shapes of the as-synthesized ZnO samples. And analyse the growth mechanism. The regular hexagonal ZnO rods align has been made by control of a certain concentration and proper PH. The hexagonal ZnO columns mainly grew in the [002] direction. X-ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence (PL) are used to characterize the structure, the morphology and optical property of the samples. The photoluminescence spectrum of hexagonal ZnO columns shows that there are a broad strong red band (650nm) and a broad band in short wavelength which are two overlapped emission bands with the peaks at about 380nm and 430nm.The UV emission (~387nm) comes from recombination of free excitons. The blue emission with peak at 430nm is assigned for the recombination from an electron at interstitial Zn to a hole in VB. The red emission at 650nm is ascribed to the recombination from an electron at Vo2+ to a hole in VB.

Hexagonal ZnO microrods and sub-microrods have been prepared through thermal decomposition of an equimolar (0.1 M) aqueous solution of Zn(NO3)2.4H2O and (CH2)6N4 at 90 degrees C for different times (10–46 h). The microrods were transformed into hollow hexagonal ZnO microtubes when the growth time reached 46 h. The Raman spectra and the photoluminescent (PL) spectra were measured. The PL spectra of microrods consist of two strong narrow near-UV bands at 380 nm and 400 nm assigned to free exciton emission and exciton–exciton collision, respectively. The PL spectrum of ZnO microtubes show only one peak in the near-UV region with peak located at 380 nm with FWHM of about 20 nm assigned to free exciton emission. When the growth time increased, the peak intensity of near-UV band decreased.

An europium(III)-doped ZnO (ZnO:Eu3+) nanopowder has been directly synthesized by a high-temperature calcination method. Under the typical UV ZnO excitation, Eu3+-doped samples exhibit strong red luminescence from Eu3+ ions with complete quenching broad emission. An energy transfer from ZnO host to Eu3+ ions can be observed.