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Equivalent models using scatter function and the statistical analysis with Hypothesis-test are provided to overcome the computational requirement for simulating complicated microstructures of photoelectronic devices. Strategies are introduced to explore the minimal number of rays and spectrum resolution to complete the analysis. Results indicate that on an average 1/25 reduction factor of computational time is possible, which is extremely helpful if an optimization procedure is required for microstructures.

Although apodization patterns have been adopted for the analysis of sputtering sources, the analytical solutions for the film thickness equations are yet limited to only simple conditions. Empirical formulations for thin film sputtering lacking the flexibility in dealing with multi-substrate conditions, a suitable cost-effective procedure is required to estimate the film thickness distribution. This study reports a cross-discipline simulation program, which is based on discrete particle Monte-Carlo methods and has been successfully applied to a non-imaging design to solve problems associated with sputtering uniformity. Robustness of the present method is first proved by comparing it with a typical analytical solution. Further, this report also investigates the overall all effects cause by the sizes of the deposited substrate, such that the determination of the distance between the target surface and the apodization index can be complete. This verifies the capability of the proposed method for solving the sputtering film thickness problems. The benefit is that an optical thin film engineer can, using the same optical software, design a specific optical component and consider the possible coating qualities with thickness tolerance, during the design stage.

In this study, the Mg doping effects on the nanostructural dependence of photoluminescence and the photosensing properties in Zn1−xMgxO (x = 0.01, 0.03, and 0.05) nanorod arrays were systematically examined. The vertical-aligned nanorod arrays were separately grown on ZnO-seeded n-Si substrates via a low-temperature hydrothermal process. X-ray diffraction analysis revealed that all Zn1−xMgxO nanorod arrays exhibited the same preferentially c-oriented wurtzite structure. Images of all the Zn1−xMgxO nanorod arrays provided by field emission scanning electron microscope showed that both the length and diameter of the Zn1−xMgxO nanorod arrays increased with increasing Mg doping concentration. Also, an enhanced blue-shifted ultraviolet (UV) emission and a reduced visible emission were observed from the photoluminescence spectra of the Zn1−xMgxO nanorod arrays. The former indicated the decrease of defects and the latter indicated the enhancement of the crystallinity and the increase in optical bandgap. Current–voltage curves were separately measured in the dark and under UV illumination. Finally, the mechanism of the Mg doping effects on the corresponding defects, bandgap, and UV photosensing characteristics of the Zn1−xMgxO nanorod arrays was investigated in detail.

Ti O2 is well recognized as the electrode for large display technology. Hydrogen generation can also be achieved by the Ti O2 array. This report reveals the using of the liquid crystal device as illuminators to explore the optimal combination of the TiO 2 sample and provide a as a performance exploring for the Hydrogen generating. Advantages and the drawbacks of the present proposal can inspire the diligence of the display technology for new energy exploration.

Simulation of the immersed light source with microstructure on the emitting surface is critical for next generation optical and bio-photonics components. Several design procedures that corresponding to the modulation of the emitting pattern is addressed. The writers are at present operating on a MOST project "Investigation of Solid Human Eye Model with 3D Printing Technology and the Evaluation on the Associate Specialized Optoelectronic Sensing Structures Fabrication to the Biocompatible Surface". We are preparing the methodology that can construct the human eye model with immersed emitting energy by the 3D printing material, and furnishes the real time estimation on the image qualities of the human eye. Our aim is to build a practical platform to evaluate the immersed optical-electronic components of the human eye. By doing this, the evaluation of the visual qualities can be amended, and it becomes possible for us to fill in an accurate measurement system that based on the eye model with immersed source. In this account, we provide several comments on the conduct of the immersed light source and the application to the details human eye modeling.

Many reports and patents address tracking-type systems to complete and optimized the acquisition of solar energy. However, fixed-type systems contribute the most of the market to the solar photovoltaic system (SPVS) for the existing buildings. Based on this fact, it is important to discuss and understand the feasible setup parameters to achieve the optimum radiation-collection-efficiency of a fixed-type system. The purpose of the present report is to provide the methodology and to investigate the optimum angles of the system facilities through minimum mathematics. The calculations show that for the demonstrated locations, the maximum efficiency for the whole year of a fixed-type system can reach more than 61% efficiency, compared to a total tracking system at the same location and time intervals. Based on these calculations, the appropriate optical system can be designed to improve system performance for the majority buildings requirements in any location.

Modelling of thermal deformation and the corresponding stress distribution are significant for the thin-film design. In order to evaluate the mechanical properties experienced by a thin film parameter on the rigid substrate, the author proposes a semi-analytical model to estimate the deformation of the thin film under various conditions. The physical interpretation and simplification of each term is obtained through the order-of-magnitude analysis. Analytical forms for the thin film deformation can be obtained, and the stress in the film can be easily determined using the proposed model through the constitutive law.

Fresnel-like prism arrays are designed using geometric ray optics and fabricated on a curved surface according to specific focal length requirements. In this study, the tolerance of Fresnel-like prism structures on arbitrary surfaces was investigated. Compact equations (iterative and non-iterative) based on analytical formulation can be helpful in exploring the sensitivity associated with the fabrication of Fresnel-like structures. The curved surface in this study revealed a linear relationship between maximum angular tolerance and the angle of incident rays. An understanding of such linearity is a key issue in the fabrication of lenses as well as in the sensitivity formulae used for optical structures in the development of next-generation optics.

Stresses distribution between the interfaces of the materials is critical for structures like thin film layers, organic/inorganic light emitting diode layers and various kinds of modern optical-electronics components with stacking materials properties. The classical Aleck's model ( 1949 ) can be considered as a very simple and a practical method to analyze these kinds of structures. In order to deal with it, the integration scheme is used to solve the displacement equations with zero displacements on the clamped edge including the clamped corner. The condition of zero traction is imposed at all of the grid points on the free surface except for the clamped corner of layers. The results show a stress singularity at the clamped corner. This agrees with an existing finite element solution performed on a very fine grid. By contrast, the known Kantorovich solution for Aleck problem from Blech and Kantor (1984) did not predict such stress singularity. As remarked by Blech and Kantor, the Kantorovich solution posed difficulties in convergence in the immediate vicinity of the clamped corner, thus is questionable to apply the results for the layer structures through this model.

SUMMARY The finite element method with linear elastic assumption for predicting the intraocular pressure (IOP) readings after reshaping of the corneal structure is demonstrated in the present study. Twelve effective eye measurements in seven subjects were examined using the TOPCON LX-10, a noncontact intraocular pressure measurement technique, before and after laser-assisted in situ Keratomileusis surgery. A linear elastic model was introduced to reduce possible errors from a complicated anisotropic model with uncertain tissue parameters. Linear relationship between the simplified removal depth of laser-assisted in situ Keratomileusis and predicted IOP was expected, and the comparisons between measurements and the predicted model were made. The results indicated that the expected IOP readings are close to the measurement IOP values, while larger errors occur at smaller IOP conditions. In conclusion, the linear elastic finite element approach can already reveal parameters that influence measurement data the most, and the interaction between parameters was higher than we had expected. This helps us to build the confidence on implementing the anisotropic model.Copyright © 2012 John Wiley & Sons, Ltd.

We report an intuitive approach to simulating the performance of the phosphor-based light emitting diode (LED) by using the two-light-sources model for an optimized LED lens. The optimized secondary lens shape is achieved by approaching a uniform energy distribution on the detecting plane. Both the spectrum and spatial apodization of the LED structure are discussed, and the results indicate that the two-light-sources model can solve the misleading design on the phosphor-based LED due to imperfect color mixing of light source, that one can satisfy the highly uniformity requirement for specific applications, such as display backlight or optogenetic.

Praseodymium-substituted bismuth titanate (Bi 3.2 Pr 0.8 Ti 3 O 12 , BPTO) thin films were successfully deposited on Pt(111)/Ti/SiO 2 /Si(100) substrates by spin coating with a sol-gel technology and rapid thermal annealing. The effects of annealing atmospheres (vacuum, ambient atmosphere and oxygen) on the growth and properties of thin films were investigated. The results show that the intensity of the (117) diffraction peak of Bi 3.2 Pr 0.8 Ti 3 O 12 film annealed in oxygen is stronger than those annealed in ambient atmosphere and vacuum. The XRD spectra demonstrated that a highly (117) orientation could be obtained when the Bi 3.2 Pr 0.8 Ti 3 O 12 thin film was annealed in an oxygen-sufficient environment. The BPTO thin films annealed in oxygen atmosphere exhibits the maximum remanent polarization (2P r ) of 49 μC/cm 2 and a low coercive field (2E c ) of 130 kV/cm, fatigue free characteristics up to ≥10 11 switching cycles. These results indicate that the BPTO thin film is useful in nonvolatile ferroelectric random access memory applications.

Spatial light modulator is introduced for cell culturing and related illumination experiment. Two kinds of designs were used. The first type put the cell along with the bio-medium directly on top of the analyzer of the microdisplay and set a cover glass on it to retain the medium environment, which turned the microdisplay into a bio-container. The second type introduced an optical lens system placed below the spatial light modulator to focus the light spots on specific position. Details of the advantages and drawbacks for the two different approaches are discussed, and the human melanocyte cell (HMC) is introduced to prove the feasibility of the concept. Results indicate that the second type is much more suitable than the first for precision required application.

We present a cost-effective optogenetic experimental setup for investigation of synaptic gating (neuron gate). The setup consists of a cell illuminating system containing a common micro-display of a commercial word processor and light emitting diode (LED) semiconductor materials instead of optogenetic cells. The performance is verified by illuminating the LED materials and measuring the induced electric potential.

We study the biocompatibility, the magnetic clustering, and the possible transfection effect of iron particles on glia cells. Results indicate that iron particles can coexist quite well with glia cells, and the inductive migration of the cell through the vanishing of the Fe compound particles around the cell is examined. Transfection experiments also prove the feasibility of using iron particles with glia cells.

Light emitting diode (LED) has more advantages compared with a traditional incandescent light bulb and a fluorescent lamp, such as small size, low quantity of heat, long life, low power consumption, fast response, plain packaging and ease of develop ment of a frivolous short product. A methodology is proposed to improve the uniformity of the LED illumination system. As a light source in a backlight unit (BLU), the requirement for optical characteristics of a LED is different from highly directional conventional ones. New diffused-type LEDs need to be developed to fulfill the requirement of the BLU industry. A non-spherical lens is designed to optimize uniformity, and a great improvement in uniformity from 28.4 to 64% is demonstrated. In the future, it may used in an LED display to improve the unevenness of illumination.

The finite element method with linear elastic assumption for predicting the intraocular pressure (IOP) readings after reshaping of the corneal structure is demonstrated in the present study. Twelve effective eye measurements in seven subjects were examined using the TOPCON LX-10, a noncontact intraocular pressure measurement technique, before and after laser-assisted in situ Keratomileusis surgery. A linear elastic model was introduced to reduce possible errors from a complicated anisotropic model with uncertain tissue parameters. Linear relationship between the simplified removal depth of laser-assisted in situ Keratomileusis and predicted IOP was expected, and the comparisons between measurements and the predicted model were made. The results indicated that the expected IOP readings are close to the measurement IOP values, while larger errors occur at smaller IOP conditions. In conclusion, the linear elastic finite element approach can already reveal parameters that influence measurement data the most, and the interaction between parameters was higher than we had expected. This helps us to build the confidence on implementing the anisotropic model.

There are many reasons that can degrade the image quality performance in a projection system, such as environment temperature, MTF of projection lens, structure of Lcd panel, EMI on the PCB and driver scheme... etc. Image quality is a function of all these parameters. In this article, the authors would like to estimate the image quality of a projection system under driver schemes and design parameters from the system point of view. The relationships between the voltage difference applied on liquid crystal (LC) cell and defect phenomenon are also revealed. This gives a clear-cut for different image defect (ex: flicker) and its causality. In the present time, ITRI/OES were modeling the LCOS Panel pixel with SpiceTM and ASAPTM for the estimation of image quality during the design of the optical engine.© (2002) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

La -doped and Cu -doped ZnO nanowires have been prepared to compare the substitution effect on the microstructural and magnetic properties. The XRD patterns of both compositions with single diffraction peak (002) show the same wurtzite hexagonal structure. The growth rate of the ZnO nanowires were enhanced by Cu doping, which were different from the suppression of growth rate by La doping. Room temperature ferromagnetism is observed for all ZnO , Cu -doped ZnO and La -doped ZnO nanowires. The saturation magnetizations are 0.102, 0.232 and 0.04 emu/g for ZnO , Cu -doped ZnO and La -doped ZnO nanowires, respectively. The results showed that the ferromagnetism is restrained by Cu doping, but enhanced by the La doping.

This report proposes a graphical-like approach for simulating the Hamiltonian of the t–J model. The two spin states are modeled by the two emitting layer, the kinematics of the electrons and the causalities between the operators are satisfied through the event cone. Operators and the event cone are integrated together, and the results indicate that this approach can provide information during the evolution of the t–J model. In addition, parameters that can be accessed by this approach are consistent with general requirements on values of t and J in the t–J model. Furthermore, our approach also includes the solution with vanishing hopping amplitude (tij = 0) and the H∞ solution.

Liquid crystals have been recognized as practical adaptive optical components for imaging and nonimaging applications. We have studied a liquid crystal lens without power modulation, as distinct from a focus modulating lens, and have simulated the effects of transient birefringence on the energy distribution on the focal plane. Our results indicate that owing to the particular transient spreading energy patterns on the focal plane, a focusing reversal phenomenon takes place during the operation of this lens, and the characteristic of the modulation transfer function (MTF) of this device indicates that this lens can serve as a spatial frequency filter.

Commercialized projection system and the LED without secondary optical lens are serving as the light source for cell illuminating experiments. Feasibilities and the application for these two approaches are discussed.

One-dimensional pure zinc oxide (ZnO) and Y-doped ZnO nanorod arrays have been successfully fabricated on the silicon substrate for comparison by a simple hydrothermal process at the low temperature of 90°C. The Y-doped nanorods exhibit the same c-axis-oriented wurtzite hexagonal structure as pure ZnO nanorods. Based on the results of photoluminescence, an enhancement of defect-induced green-yellow visible emission is observed for the Y-doped ZnO nanorods. The decrease of E2(H) mode intensity and increase of E1(LO) mode intensity examined by the Raman spectrum also indicate the increase of defects for the Y-doped ZnO nanorods. As compared to pure ZnO nanorods, Y-doped ZnO nanorods show a remarked increase of saturation magnetization. The combination of visible photoluminescence and ferromagnetism measurement results indicates the increase of oxygen defects due to the Y doping which plays a crucial role in the optical and magnetic performances of the ZnO nanorods.