ITO is a wide band gap semiconductor material, its band gap is from 4.7 eV to 5.2 eV. Due to the low resistivity, high transmittance to visible light, great absorption to UV light, and high reflection to IR, ITO is wide used to photovoltatic application; such as anodic electrode of Liquid Crystal Display (LCD) and photovoltaic devices. In the thesis, samples are deposited with an ITO layer on color filter (CF) by magnetron sputtering. The conductivity of samples is measured by 4-probe measurement, and the transmittance is characterized by visible spectroscopy. In this work is heat treatment parameters of temperature and annealing time of ITO thin film know been studied, and found an optima condition. From the experiment results, an optima heat treatment condition is temperature of 200¢Jfor 40 minutes, which reveals lower resistivity and improved transmittance of ITO samples. And, it is less process time and lower treatment temperature to used condition for industry presently. The reducing time of heat treatment will increase 9.9 % production, and enhancing the properties of color filter. Depending on the results of this work, there is space to improve performance and reduce power for fabrication of color filter.

At the age of multi-media, portable electronic devices such as mobile phones, personal digital assistant and handheld gaming systems have increased the demand for high performance displays with low cost production. Inkjet printing color optical filters (COF) for LCD applications seem to be an interesting alternative to decrease the production costs. The advantage of inkjet printing technology is to be fast, accurate, easy to run and cheaper than other technologies. In this master thesis work, we used various disciplines such as optical microscopy, rheology, inkjet printing, profilometering and colorimetry. The specific aim of the thesis was to investigate the feasibility of using company-A pigment formulation in inkjet production of COF for active matrix LCD applications. Ideal viscosity parameters were determined from 10 to 20mPa·s for easy inkjet printing at room temperature. The red pigments used are fully dispersed into the solvent and present an excellent homogenous repartition after printing. Thickness investigations revealed that the printed COF were equal or slightly thicker than typically manufactured ones. The colorimetry investigations demonstrated color coordinates very close to the NTSC red standard. LED backlighting seems to be a valuable solution to combine with the printed COF regarding to the spectrum and color analysis. The results on this thesis will increase the understanding of inkjet printing company-A pigments to produce COF for LCD applications.

OLEDs for display and lighting applications were studied. Both RGB and color filter technologies were discussed in the display section; meanwhile, RGB white light and tendem white light were discussed in the lighting section. A high performance RGB white display using 1,3,5-tri(1-pyrenyl) benzene (TPB3), C545T (166000 cd/m2) and DCJTB (70600 cd/m2) has been prepared with a 53.3% color gamut. For the color display using PLED technology, a glycerol modified PEDOT (G-PEDOT) is used as buffer layer material. Luminance of the white PLED display increases significantly from 11580 cd/m2 to 16040 cd/m2. A 54.5% color gamut color display is prepared using the white PLED device with a color filter. RGB white device with maximum luminance of 55800 cd/m2, maximum luminance efficiency of 4.55 cd/A, maximum power efficiency of 3.85 lm/W, and CIE coordinate of (0.33, 0.32) is prepared with a device structure of ITO(1300A)/NPB(500A)/TPB3(200A)/DPVBi¡G2% DSB(150A)/Alq3¡G2% DCJTB (150A)/ Alq3(350A)/LiF(8A)/Al(2000A). A high performance single emission layer white OLED device is also prepared. This single-layer device achieves a maximum luminance of 95200 cd/m2, maximum luminance efficiency of 5.9 cd/A, maximum power efficiency of 4.06 lm/W, and CIE coordinate of (0.34, 0.39) with a device structure of ITO(1300A)/NPB(650A)/TPB3:6% DSB:0.6% DCJTB(400A)/Alq3(300A)/LiF(8A)/Al(2000A). Optimization of a tandem OLED device is conducted using a Alq3¡GLi/ HAT-CN interlayer. It is found that turn-on voltage is reduced effectively using the Alq3¡GLi/ HAT-CN interlayer at 20 mA/cm2. Power efficiency is increased to 2.24 lm/W, and maximum luminance of 71790 cd/m2 is achieved with a CIE coordinate of (0.30, 0.39).

Digital cameras use a single image sensor array with a color filter array (CFA) to measure a color image. Instead of measuring a red, green, and blue value at every pixel, these cameras have a filter built onto each pixel so that only one portion of the visible spectrum is measured. To generate a full-color image, the camera must estimate the missing two values at every pixel. This process is known as color filter array interpolation. The Bayer CFA pattern samples the green image on half of the pixels of the imaging sensor on a quincunx grid. The other half of the pixels measure the red and blue images equally on interleaved rectangular sampling grids. This thesis analyzes this problem with sampling theory. The red and blue images are sampled at half the rate of the green image and therefore have a higher probability of aliasing in the output image. This is apparent when simple interpolation algorithms like bilinear interpolation are used for CFA interpolation. Two reference algorithms, a projections onto convex sets (POCS) algorithm and an edge-directed algorithm by Adams and Hamilton (AH), are studied. Both algorithms address aliasing in the green image. Because of the high correlation among the red, green, and blue images, information from the red and blue images can be used to better interpolate the green image. The reference algorithms are studied to learn how this information is used. This leads to two new interpolation algorithms for the green image. The red and blue interpolation algorithm of AH is also studied to determine how the inter-image correlation is used when interpolating these images. This study shows that because the green image is sampled at a higher rate, it retains much of the high-frequency information in the original image. This information is used to estimate aliasing in the red and blue images. We present a general algorithm based on the AH algorithm to interpolate the red and blue images. This algorithm is able to provide results that are on average, better than both reference algorithms, POCS and AH.

Typical consumer digital cameras capture the scene by generating a mosaic-like grayscale image, known as a color filter array (CFA) image. One obvious challenge in digital photography is the storage of image, which requires the development of an efficient compression solution. This issue has become more significant due to a growing demand for high dynamic range (HDR) imaging technology, which requires increased bandwidth to allow realistic presentation of visual scene. This thesis proposes two digital camera pipelines, efficiently encoding CFA image data represented in HDR format. Firstly, a lossless compression scheme exploiting a predictive coding followed by a JPEG XR encoding module is introduced. It achieves efficient data reduction without loss of quality. Secondly, a lossy compression scheme that consists of a series of processing operations and a JPEG XR encoding module is introduced. Performance evaluation indicates that the proposed method delivers high quality images at low computational costs.

Typical consumer digital cameras capture the scene by generating a mosaic-like grayscale image, known as a color filter array (CFA) image. One obvious challenge in digital photography is the storage of image, which requires the development of an efficient compression solution. This issue has become more significant due to a growing demand for high dynamic range (HDR) imaging technology, which requires increased bandwidth to allow realistic presentation of visual scene. This thesis proposes two digital camera pipelines, efficiently encoding CFA image data represented in HDR format. Firstly, a lossless compression scheme exploiting a predictive coding followed by a JPEG XR encoding module is introduced. It achieves efficient data reduction without loss of quality. Secondly, a lossy compression scheme that consists of a series of processing operations and a JPEG XR encoding module is introduced. Performance evaluation indicates that the proposed method delivers high quality images at low computational costs.

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It is of paramount importance to our society that the environment, life style, science and amusement flourish together in a balanced way. Some trends in this direction are the increased utilization of renewable energy, like solar photovoltaics; better health care products, for example advanced biosensors; high definition TV or high resolution cameras; and novel scientific tools for better understanding of scientific observations. Advancement of micro and nanotechnologies has directly and positively impacted our stance in these application domains; one example is that of vertical periodic or aperiodic nano or micro pillar assemblies which have attracted significant research and industrial interest in recent years. In particular, Si pillars are very attractive due to the versatility of silicon. There are many potential applications of Si nanopillar/nanowire assemblies ranging from light emission, solar cells, antireflection, sensing and nonlinear optical effects. Compared to bulk, Si pillars or their assemblies have several unique properties, such as high surface to volume ratios, light localization, efficient light guiding, better light absorption, selective band of light propagation etc.      The focus of the thesis is on the fabrication of Si pillar assemblies and hierarchical ZnO nanowires on Si micro structures in top-down and bottom-up approaches and their optical properties and different applications. Here, we have investigated periodic and aperiodic Si nano and micro structure assemblies and their properties, such as light propagation, localization, and selective guiding and light-matter interaction. These properties are exploited in a few important optoelectronic/photonic applications, such as optical biosensors, broad-band anti-reflection, radial-junction solar cells, second harmonic generation and color filters.         We achieved a low average reflectivity of ~ 2.5 % with the periodic Si micropyramid-ZnO NWs hierarchical arrays. Tenfold enhancement in Raman intensity is also observed in these structures compared to planar Si. These Si microstructure-ZnO NW hierarchical structures can enhance the performance and versatility of photovoltaic devices and optical sensors. A convenient top-down fabrication of radial junction nanopillar solar cell using spin-on doping and rapid thermal annealing process is presented. Broad band suppressed reflection, on average 5%, in 300- 850 nm wavelength range and an un-optimized cell efficiency of 6.2 % are achieved. Our method can lead to a simple and low cost process for high efficiency radial junction nanopillar solar cell fabrication.            Silicon dioxide (SiO2) coated silicon nanopillar (NP) arrays are demonstrated for surface sensitive optical biosensing. Bovine serum albumin (BSA)/anti-BSA model system is used for biosensing trials by photo-spectrometry in reflection mode. Best sensitivity in terms of limit of detection of 5.2 ng/ml is determined for our nanopillar biosensor. These results are promising for surface sensitive biosensors and the technology allows integration in the CMOS platform.         Si pillar arrays used for surface second harmonic generation (SHG) experiments are shown to have a strong dependence of the SHG intensity on the pillar geometry. The surface SHG can be suitable for nonlinear silicon photonics, surface/interface studies and optical sensing.         Aperiodic Si nanopillar assemblies in PDMS matrix are demonstrated for efficient color filtering in transmission mode. These assemblies are designed using the ‘‘molecular dynamics-collision between hard sphere’’ algorithm. The designed structure is modeled in a 3D finite difference time domain (FDTD) simulation tool for optimization of color filtering properties. Transverse localization effect of light in our nanopillar color filter structures is investigated theoretically and the results are very promising to achieve image sensors with high pixel densities (~1 µm) and low crosstalk. The developed color filter is applicable as a stand-alone filter for visible color in its present form and can be adapted for displays, imaging, smart windows and aesthetic applications. / <p>QC 20160407</p>