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The authors have fabricated light-emitting diodes with emission peaks from 490 to 630 nm using planar microcavity tailored luminescence from a single organic semiconductor. The optical thickness of the microcavities is controlled with a patterned inert filler. This approach obviates the need to integrate three separate emissive materials in the manufacture of full colour electroluminescent displays.

A red-emitting organic-dye-dispersed inorganic electroluminescent (EL) panel is developed using a printing technique. An EL device with Coumarin 6 and a 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran co-doped phosphor layer, which is expected to emit red light, was manufactured. Therefore, a red-emitting panel without a colour filter is obtained.

The first successful attempt at utilising pulsed KrF (248 nm) laser annealing as a post-deposition process for RF sputtered SrS:Cu,Ag phosphor films used for thin film electroluminescent (TFEL) devices is presented. Using this novel annealing method, the luminance of the TFEL devices is observed to improve as laser fluence increases. Hence, the potential for luminance improvement of SrS:Cu,Ag TFEL devices without the need for a high temperature annealing process is demonstrated.

An analytic model of the optical behaviour of laterally light emitting thin film structures is developed. It is employed to calculate the outcoupled light of a pixel used in light emitting dot matrix displays such as laterally emitting thin film electroluminescent displays (LETFEL) with micromirrors. Consequently, one can identify the optimum pixel geometry. Here, the optical behaviour of the circular, square and hexagonal pixel geometry is modelled. The presented closed form solutions are based on a ray optics approximation whereby the absorption of the light within the light generating medium (phosphor material) and the transmission behaviour of the phosphor–air interface is taken into account, as well as the micromirror width. These solutions, however, neglect back reflected light. The effect of this neglect is investigated for square pixels by taking into account the first reflection. The model is applied to a typical LETFEL display with ZnS material doped with Mn. An optimal pixel diameter of 35 μm is estimated for that particular type of display.

A technique for enhancing the performance of thin film electroluminescent devices is presented. Thin film phosphors have been processed with 20 ns pulses of 880 mJ/cm/sup 2/ laser irradiation from a 249 nm KrF excimer laser. Electroluminescent characterisation demonstrates a four-fold improvement in emitted luminous intensity, as compared to thermally annealed structures.

A see-through multi-pixel emissive display has been demonstrated. The 8/spl times/12 pixel display, fabricated on a glass substrate, has two partially transparent electrodes that sandwich multi-layer, thin film organic materials. The fabrication approach is based on common integrated circuit processing techniques and can be extended to form active matrix addressed displays on silicon substrates.

Arrays of 600 micro-pixels of organic light emitting devices were fabricated by vacuum deposition of organic molecules. Pixels with dimensions as small as 20/spl times/20 /spl mu/m/sup 2/ were easily achieved. Individual pixels showed bright green light in excess of 28,500 cd/m/sup 2/ in CW mode.

We report for the first time, the electrical and electroluminescent properties of Au/substituted silicon phthalocyanine LB film/MOCVD ZnSe MIS diodes. Underforward bias, and at room temperature the devices exhibited blue-white electroluminescence. Further investigation revealed two peaks in the spectrum. The 460nm peak coincides with the maximum output in the PL spectrum and is attributed to band-to-band recombination.

There are a number of different forms of electroluminescent panels which can be used for display purposes. The differences between these various constructions are described, and their properties and applications reviewed. Although almost all the electroluminescent devices which are in regular production are of the a.c., e.l. type; d.c., e.l. shows promise for certain types of small dynamic displays. In recent years the greatest advances have been in the technology of light emitting films (l.e.f.) and it is in this area of electroluminescence that the best prospects for future developments of a more sophisticated type of display device can be expected.

A novel thin-film electroluminescent device having a brightness/voltage characteristic depending strongly on the frequency of the excitation voltage is described. It is essentially a ZnS:Mn thin-film EL device of double-insulating-layer structure with a new dielectric layer of frequency-dependent impedance characteristic as the insulator.